Cancer Prevention Research recent issues

Cancer Chemoprevention Locks onto a New Polyamine Metabolic Target

Gerner, E. W. — Wed, 03 Feb 2010 21:06:18 PST

Ornithine decarboxylase has a relatively long history as a target for cancer chemoprevention and chemotherapy. Plym Forshell et al. report new evidence (beginning on p. 140 in this issue of the journal) indicating that spermidine synthase, a fellow enzyme of ornithine decarboxylase in polyamine metabolism, is transactivated in part by the MYC gene and is a potential target for chemoprevention of B-cell lymphomas. Cancer Prev Res; (3)2; 125–7

Assessing Efficacy in Early-Phase Cancer Prevention Clinical Trials: The Case of Ki-67 in the Lung

Szabo, E. — Wed, 03 Feb 2010 21:06:19 PST

This perspective on Kim et al. (beginning on p. 148 in this issue of the journal) examines the value of the Ki-67 proliferation index as a surrogate end point in early-phase clinical lung cancer prevention trials. The clinical trial of Kim et al. shows an effect of the cyclooxygenase-2–selective inhibitor celecoxib at a high dose on Ki-67 expression in the normal bronchial epithelia of current and former smokers. The critical issue of how these data can be used to further drug development is discussed. Cancer Prev Res; 3(2); 128–31

The Promise of Natural Products for Blocking Early Events in Skin Carcinogenesis

Clifford, J. L., DiGiovanni, J. — Wed, 03 Feb 2010 21:06:19 PST

This perspective on Stratton et al. (beginning on p. 160), Kowalczyk et al. (beginning on p. 170), and Katiyar et al. (beginning on p. 179) highlights the common theme of translational investigation of natural substances and their molecular effects and mechanisms in preventing skin squamous cell carcinoma, which has potentially severe clinical consequences. These studies comprise results of naturally occurring phytochemicals and green tea polyphenols in mouse models of UV-induced and chemically induced skin carcinogenesis and results of perillyl alcohol in a phase IIa clinical trial—all pointing to the great promise of this exciting approach for better understanding of and preventing skin cancer. Cancer Prev Res; 3(2); 132–5

The Effectiveness of Chemoprevention Agents Is Underestimated When Lesion Sizes Are Rounded

Taylor, T. H., Armstrong, W. B., Meyskens, F. L. — Wed, 03 Feb 2010 21:06:19 PST

Change in the area of premalignant lesions is an end point in estimating the efficacy of chemopreventive agents. When examiners round measurements of lesion length and width, they introduce variability, which perturbs the relative percent change in lesion area and, consequently, the percent of subjects showing a clinical response. We use simulations to illustrate the resulting bias when the agent under test is effective in reducing lesion area. We simulated 500 oral leukoplakia lesions per run, with 2,500 runs at each of five levels of agent effectiveness, namely, true relative percent reduction in area of 25%, 45%, 50%, 55%, and 75%. Realistic values of lesion lengths and widths were generated randomly and then rounded to the nearest multiple of five. The product is the distribution of mean relative percent change in lesion area and the corresponding percent of subjects showing a clinical response. Even the fifth percentile of the distribution of mean relative percent change in lesion area consistently underestimated the true value, by about 6 percentage points. The percent showing a clinical response was underestimated by 50%, 37%, and 11% for true values of reduction in lesion area of 50%, 55%, and 75%, respectively. This could easily double the required sample size for a modest phase II study. We suggest that it is cost-effective to train observers of lesion length and width to eschew rounding of measurements in the chemoprevention setting. Cancer Prev Res; 3(2); 136–9

Chemoprevention of B-Cell Lymphomas by Inhibition of the Myc Target Spermidine Synthase

Forshell, T. P., Rimpi, S., Nilsson, J. A. — Wed, 03 Feb 2010 21:06:19 PST

The oncogenic transcription factor c-Myc (Myc) is frequently overexpressed in human cancers. Myc is known to induce or repress a large set of genes involved in cell growth and proliferation, explaining the selection for mutations in cancer that deregulate Myc expression. Inhibition of ornithine decarboxylase, an enzyme of the polyamine biosynthetic pathway and a Myc target, has been shown to be chemopreventive. In the present study, we have dissected the role of another enzyme in the polyamine biosynthetic pathway, spermidine synthase (Srm), in Myc-induced cancer. We find that Srm is encoded by a Myc target gene containing perfect E-boxes and that it is induced by Myc in a direct manner. RNA interference against Srm shows that it is important for Myc-induced proliferation of mouse fibroblasts but to a lesser extent for transformation. Using the compound trans-4-methylcyclohexylamine, we show that Srm inhibition can delay the onset of B-cell lymphoma development in -Myc transgenic mice. We therefore suggest that inhibition of Srm is an additional chemopreventive strategy that warrants further consideration. Cancer Prev Res; 3(2); 140–7

Biological Activity of Celecoxib in the Bronchial Epithelium of Current and Former Smokers

Wed, 03 Feb 2010 21:06:19 PST

Non–small cell lung cancer is the primary cause of cancer-related death in Western countries. One important approach taken to address this problem is the development of effective chemoprevention strategies. In this study, we examined whether the cyclooxygenase-2 inhibitor celecoxib, as evidenced by decreased cell proliferation, is biologically active in the bronchial epithelium of current and former smokers. Current or former smokers with at least a 20 pack-year (pack-year = number of packs of cigarettes per day times number of years smoked) smoking history were randomized into one of four treatment arms (3-month intervals of celecoxib then placebo, celecoxib then celecoxib, placebo then celecoxib, or placebo then placebo) and underwent bronchoscopies with biopsies at baseline, 3 months, and 6 months. The 204 patients were primarily (79.4%) current smokers: 81 received either low-dose celecoxib or placebo and 123 received either high-dose celecoxib or placebo. Celecoxib was originally administered orally at 200 mg twice daily and the protocol subsequently increased the dose to 400 mg twice daily. The primary end point was change in Ki-67 labeling (from baseline to 3 months) in bronchial epithelium. No cardiac toxicities were observed in the participants. Although the effect of low-dose treatment was not significant, high-dose celecoxib decreased Ki-67 labeling by 3.85% in former smokers and by 1.10% in current smokers—a significantly greater reduction (P = 0.02) than that seen with placebo after adjusting for metaplasia and smoking status. A 3- to 6-month celecoxib regimen proved safe to administer. Celecoxib (400 mg twice daily) was biologically active in the bronchial epithelium of current and former smokers; additional studies on the efficacy of celecoxib in non–small cell lung cancer chemoprevention may be warranted. Cancer Prev Res; 3(2); 148–59

A Phase 2a Study of Topical Perillyl Alcohol Cream for Chemoprevention of Skin Cancer

Wed, 03 Feb 2010 21:06:19 PST

The chemopreventive and antitumor properties of perillyl alcohol (POH) that were studied preclinically indicate that topical POH inhibits both UVB-induced murine skin carcinogenesis (squamous cell tumor models) and 7,12-dimethylbenz(a)anthracene–induced murine melanoma (transgenic models involving tyrosinase-driven Ras). A previous phase 1 clinical trial in participants with normal-appearing skin showed that topical POH cream was well tolerated at a dose of 0.76% (w/w). Here, we performed a 3-month, double-blind, randomized, placebo-controlled phase 2a trial of two different doses of topical POH in individuals with sun-damaged skin. Participants applied POH cream twice daily to each dorsal forearm. Baseline and end-of-study biopsies were taken from each participant to evaluate whether the topical application of POH was effective in reversing actinic damage as evidenced by normalization of quantitative skin histopathologic scores and change in nuclear chromatin pattern as measured by karyometric analysis. There was a borderline reduction in the histopathologic score of the lower-dose POH group compared with the placebo (P = 0.1), but this was not observed in the high-dose group. However, in the high-dose group, a statistically significant reduction in the proportion of nuclei deviating from normal was observed by the use of karyometric analysis (P < 0.01). There was no statistical significance shown in the lower-dose group. No changes were observed in p53 expression, cellular proliferation (by proliferating cell nuclear antigen expression), or apoptosis in either treatment group compared with the placebo group. These results suggest that whereas our karyometric analyses can detect a modest effect of POH in sun-damaged skin, improved delivery into the epidermis may be necessary. Cancer Prev Res; 3(2); 160–9

Synergistic Effects of Combined Phytochemicals and Skin Cancer Prevention in SENCAR Mice

Wed, 03 Feb 2010 21:06:19 PST

The purpose of our study was to determine the inhibitory effect of combined phytochemicals on chemically induced murine skin tumorigenesis. Our hypothesis was that concurrent topical and dietary treatment with selected compounds would lead to more efficient prevention of skin cancer. We tested ellagic acid and calcium D-glucarate as components of diets, while resveratrol was applied topically; grape seed extract was applied topically or in the diet. The 4-week inflammatory-hyperplasia assay based on the 7,12-dimethylbenz[a]anthracene (DMBA)–induced skin carcinogenesis model in SENCAR mice was used. We have found that all the selected combinations caused a marked decrease of epidermal thickness compared with the DMBA-treated group and also with groups treated with a single compound and DMBA. All combinations of resveratrol with other compounds showed a synergistic effect on hyperplasia and Ha-ras mutations. Skin tissue of mice receiving the combinations showed decreased cell proliferation and Bcl2 expression; decreased p21, a regulator of cell cycle; and decreased marker of inflammation cyclooxygenase-2. All the selected combinations diminished the DMBA-induced mRNA expression of the CYP1B1 level, and also caused a marked decrease of proto-oncogenes c-jun and c-fos, components of transcription factor activator protein. In conclusion, all combinations showed either additive or synergistic effects and their joint actions allowed for decreasing the doses of the compounds. Especially, resveratrol combinations with ellagic acid, grape seed extract, and other phytochemicals are very potent inhibitors of skin tumorgenesis, based on the suppression of epidermal hyperplasia as well as on the modulation of intermediate biomarkers of cell proliferation, cell survival, inflammation, oncogene mutation, and apoptosis. Cancer Prev Res; 3(2); 170–8

Green Tea Polyphenols Prevent UV-Induced Immunosuppression by Rapid Repair of DNA Damage and Enhancement of Nucleotide Excision Repair Genes

Katiyar, S. K., Vaid, M., van Steeg, H., Meeran, S. M. — Wed, 03 Feb 2010 21:06:19 PST

UV radiation–induced immunosuppression has been implicated in the development of skin cancers. Green tea polyphenols (GTP) in drinking water prevent photocarcinogenesis in the skin of mice. We studied whether GTPs in drinking water (0.1-0.5%, w/v) prevent UV-induced immunosuppression and (if so) potential mechanisms of this effect in mice. GTPs (0.2% and 0.5%, w/v) reduced UV-induced suppression of contact hypersensitivity (CHS) in response to a contact sensitizer in local (58-62% reductions; P < 0.001) and systemic (51-55% reductions; P < 0.005) models of CHS. Compared with untreated mice, GTP-treated mice (0.2%, w/v) had a reduced number of cyclobutane pyrimidine dimer–positive (CPD⁺) cells (59%; P < 0.001) in the skin, showing faster repair of UV-induced DNA damage, and had a reduced (2-fold) migration of CPD⁺ cells from the skin to draining lymph nodes, which was associated with elevated levels of nucleotide excision repair (NER) genes. GTPs did not prevent UV-induced immunosuppression in NER-deficient mice but significantly prevented it in NER-proficient mice (P < 0.001); immunohistochemical analysis of CPD⁺ cells indicated that GTPs reduced the numbers of UV-induced CPD⁺ cells in NER-proficient mice (P < 0.001) but not in NER-deficient mice. Southwestern dot-blot analysis revealed that GTPs repaired UV-induced CPDs in xeroderma pigmentosum complementation group A (XPA)–proficient cells of a healthy person but did not in XPA-deficient cells obtained from XPA patients, indicating that a NER mechanism is involved in DNA repair. This study is the first to show a novel NER mechanism by which drinking GTPs prevents UV-induced immunosuppression and that inhibiting UV-induced immunosuppression may underlie the chemopreventive activity of GTPs against photocarcinogenesis. Cancer Prev Res; 3(2); 179–89

DNA Damage Drives an Activin A-Dependent Induction of Cyclooxygenase-2 in Premalignant Cells and Lesions

Wed, 03 Feb 2010 21:06:19 PST

Cyclooxygenase-2 (COX-2) catalyzes the rate-limiting step in the synthesis of prostaglandins. Its overexpression induces numerous tumor-promoting phenotypes and is associated with cancer metastasis and poor clinical outcome. Although COX-2 inhibitors are promising chemotherapeutic and chemopreventative agents for cancer, the risk of significant cardiovascular and gastrointestinal complications currently outweighs their potential benefits. Systemic complications of COX-2 inhibition could be avoided by specifically decreasing COX-2 expression in epithelial cells. To that end, we have investigated the signal transduction pathway regulating the COX-2 expression in response to DNA damage in breast epithelial cells. In variant human mammary epithelial cells that have silenced p16 (vHMEC), double-strand DNA damage or telomere malfunction results in a p53- and activin A–dependent induction of COX-2 and continued proliferation. In contrast, telomere malfunction in HMEC with an intact p16/Rb pathway induces cell cycle arrest. Importantly, in ductal carcinoma in situ lesions, high COX-2 expression is associated with high H2AX, TRF2, activin A, and telomere malfunction. These data show that DNA damage and telomere malfunction can have both cell-autonomous and cell-nonautonomous consequences and can provide a novel mechanism for the propagation of tumorigenesis. Cancer Prev Res; 3(2); 190–201

Cyclooxygenase-2 Inhibition for the Prophylaxis and Treatment of Preinvasive Breast Cancer in a Her-2/Neu Mouse Model

Tran-Thanh, D., Buttars, S., Wen, Y., Wilson, C., Done, S. J. — Wed, 03 Feb 2010 21:06:19 PST

Ductal carcinoma in situ (DCIS) is the most common form of preinvasive breast cancer. Several molecular alterations have been identified in DCIS. Among them, cyclooxygenase 2 (COX-2) overexpression has been shown in 60% to 80% of DCIS cases. Celecoxib is a nonsteroidal anti-inflammatory drug that selectively inhibits COX-2. In this study, we evaluated whether COX-2 inhibition by celecoxib can reduce the incidence of preinvasive breast cancer and its progression to invasive breast cancer in a mouse model exhibiting a similar phenotype to human solid-pattern DCIS. We have used the mouse model mouse mammary tumor virus (MMTV)-Neu to investigate this possibility. These mice carry a rat Her-2/Neu transgene and are known to develop DCIS-like lesions. Our results showed that celecoxib (500 ppm) given as prophylaxis was neither able to prevent tumor development nor delay tumor appearance compared with untreated mice. Furthermore, when the drug was given early in tumorigenesis, it did not reduce the progression of preinvasive to invasive tumors nor prevent lung metastasis. Reduction of prostaglandin levels was, however, achieved in mammary tumors of treated mice. In addition, celecoxib treatment caused an increase in apoptosis and decreased vascular endothelial growth factor expression in treated animals. Our results contrast with some previously published studies and highlight the complexity of the relationship between COX-2 and breast cancer. Cancer Prev Res; 3(2); 202–11

A Proposed Unified Mechanism for the Reduction of Human Breast Cancer Risk by the Hormones of Pregnancy

Wed, 03 Feb 2010 21:06:19 PST

Parity in women is associated with reduced lifetime risk of breast cancer, and hormones of pregnancy [estrogen (E), progesterone (P), human chorionic gonadotropin (hCG)] are implicated. Parity also reduces mammary cancer risk in carcinogen-exposed rats, and administering pregnancy hormones to these animals is similarly effective. Because pregnancy hormones are also able to stimulate cancer growth, we proposed to resolve this dichotomy by determining whether administered pregnancy hormones elicit the cancer-inhibiting agent -fetoprotein (AFP) from the liver, which would implicate AFP as a proximal effector of hormonal anticancer activity. Accordingly, we treated groups of nitrosomethylurea-exposed rats with saline, E₃, E₂ + P, E₃ + P, hCG, or allowed them to experience pregnancy, and then monitored mammary cancer incidence and serum levels of AFP over time. Each hormone treatment reduced mammary cancer incidence and elevated serum AFP levels. To challenge human tissues, human HepG2 liver cells in culture were treated with the same hormonal agents. Each hormone regimen increased the levels of AFP in the culture medium. Medium containing AFP elicited by hCG inhibited the E₂-stimulated proliferation of cultured human MCF7 breast cancer cells, whereas hCG alone did not inhibit their growth. Furthermore, antibodies to AFP neutralized the growth-inhibiting effect of AFP-containing HepG2 medium. We conclude that in the treatment of carcinogen-exposed rats with the hormones of pregnancy, and by inference in women who have experienced pregnancy, that AFP is a proximal agent that inhibits mammary gland cancer. Cancer Prev Res; 3(2); 212–20

Cancer Chemopreventive Activity and Metabolism of Isoliquiritigenin, a Compound Found in Licorice

Wed, 03 Feb 2010 21:06:19 PST

Isoliquiritigenin (2',4',4-trihydroxychalcone; ILG), a chalcone found in licorice root and many other plants, has shown potential chemopreventive activity through induction of phase II enzymes such as quinone reductase-1 in murine hepatoma cells. In this study, the in vivo metabolism of ILG was investigated in rats. In addition, ILG glucuronides and ILG-glutathione adducts were observed in human hepatocytes and in livers from rats treated with ILG. ILG glucuronides were detected in both plasma and rat liver tissues. In addition, in a full-term cancer chemoprevention study conducted with 7,12-dimethylbenz(a)anthracene–treated female Sprague-Dawley rats, dietary administration of ILG slightly increased tumor latency but had a negative effect on the incidence of mammary tumors starting at ~65 days after 7,12-dimethylbenz(a)anthracene administration. Further, no significant induction of phase II enzymes was found in mammary glands, which is consistent with the low level of ILG observed in these tissues. However, ILG significantly induced quinone reductase-1 activity in the colon, and glutathione as well as glutathione S-transferase in the liver. Analysis of mRNA expression in tissues of rats treated with ILG supported these findings. These results suggest that ILG should be tested for chemopreventive efficacy in nonmammary models of cancer. Cancer Prev Res; 3(2); 221–32

Estimating the Attributable Fraction for Cancer: A Meta-analysis of Nevi and Melanoma

Olsen, C. M., Carroll, H. J., Whiteman, D. C. — Wed, 03 Feb 2010 21:06:19 PST

Epidemiologic research has shown convincingly that certain phenotypic attributes are associated with increased relative risks of melanoma. Although such findings have intrinsic utility, there have been few attempts to translate such knowledge into estimates of disease burden suitable for framing public health policy. We aimed to estimate the population attributable fraction (PAF) for melanoma associated with melanocytic nevi using relative risk estimates derived from a systematic review and meta-analysis. We identified eligible studies using citation databases, followed by manual review of retrieved references. Of 49 studies identified, 25 and 23, respectively, were included in meta-analyses of atypical and common nevi. For people with ≥1 atypical nevi, the summary relative risk was 3.63 (95% confidence interval, 2.85-4.62), with a PAF of 0.25. The relative risk increased by 1.017 (95% confidence interval, 1.014-1.020) for each common nevus; however, significant heterogeneity in risk estimates was observed. We estimated that 42% of melanomas were attributable to having ≥25 common nevi (PAF 25-49 nevi = 0.15; PAF ≥50 nevi = 0.27), whereas PAFs for low nevus counts were modest (PAF 0-10 nevi = 0.04; PAF 11-24 nevi = 0.07). We modeled PAF under scenarios of varying nevus prevalence; the highest melanoma burden was always among those with high nevus counts (PAF range of 0.31-0.62 for ≥25 common nevi). Patients with ≥25 common nevi and/or ≥1 atypical nevi are a high-risk group, which might be targeted for identification, screening, and education. This work is the necessary first step in designing targeted preventive strategies for melanoma, which must now be overlaid with information about cost and utility. Cancer Prev Res; 3(2); 233–45

The Six-Nucleotide Deletion/Insertion Variant in the CASP8 Promoter Region Is Inversely Associated with Risk of Squamous Cell Carcinoma of the Head and Neck

Wed, 03 Feb 2010 21:06:19 PST

Caspase 8 (CASP8) is an apoptosis-related cysteine peptidase involved in the death receptor pathway and likely in the mitochondrial pathway. A CASP8 promoter region six-nucleotide deletion/insertion (–652 6N ins/del) variant and a coding region D302H polymorphism are reportedly important in cancer development, but no reported study has assessed the associations of these genetic variations with risk of head and neck cancer. In a hospital-based study of non-Hispanic whites, we genotyped CASP8 –652 6N del and 302H variants in 1,023 patients with squamous cell carcinoma of the head and neck (SCCHN) and 1,052 cancer-free controls. Crude and adjusted odds ratios (OR) and 95% confidence intervals (CI) were estimated using unconditional logistic regression models. The CASP8 –652 6N del variant genotypes or haplotypes were inversely associated with SCCHN risk (adjusted OR, 0.70; 95% CI, 0.57-0.85 for the ins/del + del/del genotypes compared with the ins/ins genotype; adjusted OR, 0.73; 95% CI, 0.55-0.97 for the del-D haplotype compared with the ins-D haplotype). Furthermore, the number of the CASP8 –652 6N del (but not 302H) variant allele tended to correlate with increased levels of camptothecin-induced p53-mediated apoptosis in T lymphocytes from 170 cancer-free controls. We concluded that the CASP8 –652 6N del variant allele may contribute to the risk of developing SCCHN in non-Hispanic white populations. Further validation by population-based case-control studies and rigorous mechanistic studies is warranted. Cancer Prev Res; 3(2); 246–53

Abstract A1: An miR-502 binding site single-nucleotide polymorphism in the 3'-untranslated region of the SET8 gene is associated with early age of breast cancer onset

Thu, 07 Jan 2010 13:54:00 PST

Purpose: MicroRNAs regulate gene expression by binding to the 3'-untranslated region (UTR) of target genes. Single-nucleotide polymorphisms of critical genes may affect their regulation by microRNAs. We have identified a single nucleotide polymorphism within the miR-502 seed binding region in the 3'-UTR of the SET8 gene. SET8 methylates TP53 and regulates genome stability. We investigated the role of this SET8 single nucleotide polymorphism and in concert with the TP53 codon72 single nucleotide polymorphism in the propensity for onset of breast cancer.

Experimental Design: We measured the SET8 single nucleotide polymorphisms in a case-control study on 1110 breast cancer cases and 1097 controls.

Results: The SET8 CC and TP53 GG genotypes were independently associated with an earlier age of breast cancer onset in an allele-dose-dependent manner (for SET8, 52.2 years for TT, 51.4 for TC, and 49.5 for CC; and for TP53, 53.1 years for CC, 51.5 for GC, 50.7 for GG). Individuals with combined SET8 CC and TP53 GG genotypes developed cancer at a median age of 47.7 years as compared with 54.6 years for individuals with combined SET8 TT and TP53 CC genotypes. In the 51 breast cancer tissue samples tested, the SET8 CC genotype was associated with reduced SET8, but not miR-502, transcript levels.

Conclusions: These data suggest that the miR-502 binding site single nucleotide polymorphism in the 3'-UTR of SET8 modulates SET8 expression and contributes to the early development of breast cancer, either independently or together with the TP53 codon 72 single nucleotide polymorphism. Larger studies with multiethnic groups are warranted to validate our findings.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A1.

Abstract B1: Chatting about lung cancer: Utilization of NCI's LiveHelp cancer communication service

Thu, 07 Jan 2010 13:54:12 PST

Background: As the voice of the National Cancer Institute, the Cancer Information Service (CIS) maintains the mission of communicating evidence-based cancer information to the public, including cancer patients, family members, friends, and health care professionals. While the CIS is predominantly a telephone-based service, the new LiveHelp format offers online information seekers the opportunity to use an instant messaging platform to ask questions and seek assistance from highly trained cancer information specialists (IS). Although LiveHelp has been in operation since 2003, no data exists regarding this novel and expanding method of conveying cancer information and communicating with cancer information consumers. The study aims were: (1) to characterize the purpose of the contact, discussion topics, and resources utilized in LiveHelp sessions focused on lung cancer and (2) to provide descriptive demographic information regarding lung cancer information seekers.

Methods: Information captured in the Electronic Contact Record Form (ECRF) associated with each LiveHelp session was used to address study aims. The ECRF contains data coded by ISs during or following each contact. A pre-existing coding scheme is used by ISs to report the purpose of the session and subsequent actions taken. Additionally, approximately 25% of respondents are asked to complete a demographic survey following the LiveHelp session. Data from all lung cancer-related LiveHelp sessions conducted in 2008 were analyzed.

Results: Of the 20,939 LiveHelp sessions in 2008, lung cancer was the second most common malignancy addressed (n=1,179, 5.6%). Most users were relatives or friends of cancer patients (66%) and relatively few were cancer patients (13%). The contact purpose was generally motivated by a concern about a family member or friend with cancer (47%), but contacts also sought to understand medical information (25%) or address questions about personal health concerns (10%). The primary subject of the contact was most commonly lung cancer-specific information (e.g., staging, prognosis [42%]), but also frequently addressed treatment or side effect management issues (16%). ISs primarily referred contacts to the NCI's cancer.gov portal (79%). Secondary referrals included recommending review of CIS fact sheets (40%) and consulting with a health care provider (28%). With regard to available demographic information (n=159), users were predominantly female (81%), Caucasian (87%), had a bachelor's degree or higher (55%), had private health insurance (60%), and were an average age of 43 years (±14). Surprisingly, 30% reported having no access to healthcare. The vast majority of users initially located LiveHelp via the Internet (80%) and were first-time CIS users (89%).

Conclusions: Given its prevalence and impact, it is not surprising that lung cancer is the most common non-sex-specific malignancy for which individuals contact LiveHelp. Interestingly, the vast majority of these contacts are generated by family or friends of individuals diagnosed with lung cancer. Although descriptive data regarding the users and content of LiveHelp provides basic information about its educational and support functions, analyzing the information exchange embedded in the content of the session transcripts would provide an even greater understanding of how to optimize cancer communication efforts via LiveHelp.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B1.

Abstract PR-01: Vitamin D receptor expression is inversely associated with prostate cancer progression

Thu, 07 Jan 2010 13:54:29 PST

Background: Vitamin D is inversely associated with risk of several malignancies. Circulating vitamin D interacts with the vitamin D receptor (VDR) at the cellular level to inhibit proliferation, increase apoptosis and decrease angiogenesis. Thus, although vitamin D levels appear to be unrelated to total prostate cancer incidence, VDR levels in tumor tissue may influence prostate cancer prognosis.

Methods: We examined the immunohistochemical expression of VDR on archival tumor tissue from 841 prostate cancer cases diagnosed between 1982 and 2004 within two ongoing, prospective cohorts: the Physicians' Health Study and Health Professionals Follow-up Study. VDR expression was measured quantitatively using the CRi Vectra^TM system. We used Cox proportional hazards regression to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the association of VDR expression with lethal prostate cancer (N=73) through 2008. On a subset of cases, we also examined correlation of tumor VDR expression with circulating 25(OH)D3 and 1alpha,25(OH)2D3 measured at baseline (N=84) in 1982 and two SNPs in VDR: Fok1 and bsm1 (N=140).

Results: Men with high tumor VDR expression had significantly lower Gleason score, lower prostate specific antigen (PSA) levels at diagnosis, and were less likely to have advanced tumor stage (p=0.008, p=0.012, p=0.001, respectively). Compared to the lowest quartile, men in the highest quartile of VDR expression were at significantly lower risk of developing lethal prostate cancer (age-adjusted HRs across quartiles Q2=0.95, 95% CI: 0.51–1.79; Q3=0.93, 95% CI: 0.49–1.76; Q4 = 0.23, 95% CI:0.09–0.55). This association was attenuated (HRQ4vsQ1 = 0.42, 95% CI: 0.16–1.09) after further adjustment for pathological tumor stage, Gleason grade, and PSA level at diagnosis. Tumors expressing high levels of VDR had modest downregulation of cell proliferation as measured by Ki67 (r=-0.11). Moreover, expression of estrogen receptor alpha (r=0.40, p<0.001) and androgen receptor (r=0.41, p<0.001) were positively correlated with VDR expression. Neither prediagnostic plasma vitamin D levels nor gene variants in VDR were associated with VDR protein expression in tumors.

Conclusion: In this large prospective study, men with tumors that demonstrated upregulation of VDR had significantly improved clinical features and reduced risk of lethal prostate cancer. In line with experimental studies, the positive correlation between VDR expression, and androgen receptor and estrogen receptor provides evidence that that VDR acts in an androgen- and/or estrogen-dependent manner. These data highlight the potential role of the vitamin D system in preventing prostate cancer progression.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):PR-01.

Abstract A2: Genetic variation in estrogen receptor genes and mammographic breast density

Lloyd, S. M., Diergaarde, B. — Thu, 07 Jan 2010 13:54:00 PST

Mammographic density is one of the strongest, independent risk factors in the development of breast cancer. Women with mammographically dense breasts, those with greater than or equal to 75% dense tissue, are at a four to six-fold greater risk of developing breast cancer when compared to those with "no measurable dense tissue," in which the breasts are composed entirely of fat. Many of the established risk factors for breast cancer have been shown to be associated with variations in breast density (i.e., age, menopausal status, parity, BMI, and postmenopausal hormone use). Additionally, twin studies have also shown that heritability accounts for approximately 60% of the variance in mammographic density. Given the established role of estrogens in the development and progression of breast cancer, we have evaluated the role of 17 single-nucleotide polymorphisms (SNPs) in the estrogen receptor 1 and 2 genes (ESR1 and ESR2), and the recently identified G-Protein Coupled Estrogen Receptor 1 (GPER) gene, which has been demonstrated to regulate physiologic responses to estrogens independent of the traditional estrogen receptors.

This study population consisted of 370 cancer-free (excluding cancers of the skin) Caucasian, postmenopausal women enrolled in the Mammograms and Masses Study (MAMS). Three different measures of mammographic density were computed: dense breast area, total breast area, and percent breast density, using the classification system developed by Wolfe in 1976, and a compensating polar planimeter, wax pencil, and transparent overlay. Breast density was calculated as the proportion of visibly dense breast to total breast area, expressed as a percentage. DNA was extracted from buffy coat samples, and genotyping was done using the Sequenom iPLEX Gold Assay. Heterozygote and homozygous variant genotypes were collapsed and compared to the common allele genotype for all statistical analyses. General linear models and ² analyses were conducted. We arranged our percent density variable into tertiles for further analysis.

We observed that three SNPs in ESR2 (rs12435857, rs1256044, and rs1256031) were significantly associated with percent mammographic density. For ESR2 rs1256044 and rs1256031, mean percent mammographic density was significantly higher among women with at least one rare allele compared to women homozygous for the common allele (respectively, P=0.02 and P=0.03). Conversely, mean percent mammographic density was significantly higher among women with ESR2 rs12435857 GG genotype compared to those with GA/AA genotypes, 29.0 and 23.7, respectively (P=0.03).

Our results suggest that common genetic variation in ESR2 is associated with percent mammographic density. Since estrogen receptor genes are highly expressed in breast tissue, functional SNPs in these genes may alter breast cancer risk, by altering mammographic density.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A2.

Abstract B2: Associations between self-reported versus objectively measured physical activity, biomarkers, and obesity in adolescents and adults

Thu, 07 Jan 2010 13:54:13 PST

Epidemiological studies, based entirely on self-reported levels of physical activity (PA), indicate that PA reduces cancer risk at several sites. However, self reported PA is subject to the cognitive challenges of estimating its duration and intensity, and potential recall bias. Objective measurement of PA using accelerometers is an alternative to self report, even in large population studies of both children and adults

Data for adults aged 20+ years (N=4417) with self-reported PA and 4 or more days of accelerometer data were obtained from the 2003–2006 National Health and Nutritional Examination Survey (NHANES). NHANES is a nationally representative sample of the US civilian, non-institutionalized population. Outcome measures were blood pressure, body mass index (BMI), waist circumference, triceps and subscapular skinfolds, cholesterol, triglyceride, c-reactive protein, homocysteine, and indices of insulin resistance and hyperinsulinaemia. Data for adolescents, (N = 723), were obtained from two cohorts in the Twin Cities, Minnesota. PA was measured using two self report instruments, the Modified Activity Questionnaire (MAQ) assessing past week moderate and vigorous PA (MVPA), the 3-Day Physical Activity Recall (3DPAR), and accelerometer data. Biomarkers included systolic and diastolic blood pressure (SBP, DBP), lipids (total cholesterol, LDL, HDL, % body fat (BF) and BMI. For both adolescents and adults, accelerometer data was summarized as total minutes of (MVPA).

In adults, objectively-measured MVPA displayed stronger associations with most biomarkers compared with self-reported MVPA, even after adjusting for sociodemographic and health factors (Adj Wald F's = 5.1 to 55.4; p's < 0.05 to 0.0001). Adjustment for objectively measured PA eliminated some but not all associations between self-reported PA and biomarkers. Both measures of MVPA were independently associated with skinfold anthropometric measures, HDL, and c-reactive protein.

In adolescents, after controlling for puberty, age and gender, all three PA measures had a strong, negative association with %BF (MAQ β = –1.77, p<0.001; 3DPAR β = –1.43, p<0.001; accelerometer β = –1.41, p<0.003). The MAQ and accelerometry were negatively associated with BMI (β = –3.17, p=0.003; β =–2.97, p =0.01), and the MAQ was negatively associated with DBP (β = –1.30, p=0.01). None of the PA measures were significantly associated with SBP or lipids.

These results suggest that use of self-reported physical activity measures could attenuate associations between PA and several biomarkers related to energy balance in adults, but this was not observed for a few biomarkers in adolescents. Considerable care should be taken in the choice of PA measure for any study, but especially where the effects of PA are manifest all or in part via its impact on biological variables such as serum biomarkers or anthropometric characteristics.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B2.

Abstract PR-02: Dietary fat intake and risk of ovarian cancer in the NIH-AARP Diet and Health Study

Blank, M. M., Wentzensen, N., Hollenbeck, A., Schatzkin, A., Park, Y. — Thu, 07 Jan 2010 13:54:29 PST

Dietary fat is known to change estrogen levels and has been postulated to increase risk of ovarian cancer. However, previous studies of dietary fat and ovarian cancer have reported inconsistent results. Therefore, we investigated whether total, saturated, monounsaturated, polyunsaturated, animal, or vegetable fat intake is associated with risk of ovarian cancer in a large prospective cohort study, the NIH-AARP Diet and Health Study. We assessed dietary intake with a 124-item food frequency questionnaire and other risk factors at baseline in 1995–1996. Cancer ascertainment was accomplished with matching of the participants to the state cancer registry database. We defined cases as invasive, first primary epithelial ovarian cancer. The relative risks (RR) and 95% confidence interval (CI) were estimated using the Cox proportional hazard model, with multivariate adjustment for age, race, education, body mass index, parity, use of oral contraceptive and menopausal hormone therapy, and total energy intake. During follow-up through 2003, we identified 482 ovarian cancer cases (253 serous tumor and 229 nonserous tumor). We found that total fat intake was significantly positively associated with risk of ovarian cancer. Women in the highest, compared to the lowest, quintile of total fat intake had a 43% increased risk of ovarian cancer (RR_{Q5 vs. Q1}=1.43, 95% CI, 1.07–1.92; P_trend=0.02). The association did not differ by cancer subtypes: both serous and nonserous tumors were related to an increased risk of ovarian cancer. Comparing the highest versus the lowest quintile of total fat intake, RR was 1.49 (95% CI:0.99–2.24. p trend=0.19) for serous tumor and 1.37 (95% CI:0.90–2.08, p trend=0.04) for nonserous tumor. When types of fat were examined, we found that polyunsaturated fat intake was associated with an increased risk of ovarian cancer when comparing the highest and lowest quintiles of intake (RR_{Q5 vs. Q1}, 1.46; 95% CI, 0.99–2.17; P_trend=0.05). Monounsaturated and saturated fat intakes were unassociated with risk of ovarian cancer. Animal fat intake was related to a slight increased risk, while vegetable fat intake was unrelated. When we tested for interactions by use of oral contraceptive and menopausal hormone therapy, parity, and body mass index, we observed no significant interactions. However, total fat intake was associated with ovarian cancer risk only in women who have never used oral contraceptives (RR_{Q5 vs. Q1}=1.81, 95% CI:1.24–2.66; P_trend<0.01), in those who were nulliparous (RR_{Q5 vs. Q1}=2.18, 95% CI:1.05–4.50; P_trend= 0.02), or in women who used menopausal hormone therapy for more than 5 years (RR_{Q5 vs. Q1}=1.79, 95% CI:1.03–3.11; P_trend= 0.13). In summary, we found that total fat intake was significantly related to an increased risk of ovarian cancer. Risk attributable to sources and types of fats and interactions by oral contraceptive, parity, and menopausal hormone therapy warrants further investigation.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):PR-02.

Abstract A3: MicroRNA-related polymorphisms are associated with clinical outcomes in early stage non-small cell lung cancer patients

Thu, 07 Jan 2010 13:54:00 PST

MicroRNAs (miRNA) can function as oncogenes or tumor suppressors. In this study, to test the hypothesis that genetic variation within miRNA processing genes or miRNA binding sites on cancer-related genes may alter clinical outcomes in non-small cell cancer (NSCLC) patients, we genotyped 77 single nucleotide polymorphisms (SNPs) from eight miRNA processing genes and 163 SNPs from 133 predicted miRNA binding sites in 598 patients with early stage (stage I, IIA and IIB) NSCLC to determine the effect of these variations on progression risk and overall survival. We further conducted a subset analysis to exclude potential bias due to different treatment regimens. We identified 37 SNPs associated with overall survival. In the surgery-only patients, 22 SNPs modulated overall survival, including FZD4:rs713065 that remained significant for decreased risk after multiple comparisons (HR: 0.53, 95% CI: 0.36–0.77). For progression risk, 21 and 25 SNPs were found to be significant in the entire and surgery-only patient populations, respectively. Following multiple comparison, ICAM1:rs281437 (HR: 1.80, 95% CI: 1.29–2.52) and MDM4:rs10900596 (HR: 2.01, 95% CI: 1.26–3.19) remained significant increase in progression risk, while FAS:rs2234978 (HR: 0.58, 95% CI: 0.41–0.80) displayed a significantly protective effect. CDC7:rs12125947 (HR: 2.19, 95% CI: 1.37–3.51) remained significant risk effect in the surgery-only patients. A strong cumulative, dose-effect of these variant genotypes to increase risk and dramatically decrease median event-free time was consistently observed. We also identified potential higher-order gene-gene interactions among these SNPs. With validation, our result can be used in the prognosis of clinical outcomes for early stage NSCLC patients.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A3.

Abstract B3: Effect of consuming pistachios on the intake and serum levels of {gamma}-tocopherol

Hernandez, L. M., Forman, M. R., Radcliffe, J. D. — Thu, 07 Jan 2010 13:54:13 PST

Pistachios are one of the best dietary sources of gamma-tocopherol (-T), a form of vitamin E that may help to protect against certain forms of cancer, such as lung among high risk groups like smokers. We investigated the effect of the incorporation of pistachios (at a level of 68 g per day) on the intakes and serum cholesterol-adjusted -T (micromole/millimole) using a six-week randomized, controlled, clinical trial design, having a two-week preintervention period and a four-week intervention period. Participants (n = 36) were healthy males and females, randomized to either the control group or the intervention group. Intakes were calculated using the Nutrition Data System for Research Version 2007. Diet diaries and weights of returned pistachios were reviewed to assess consumption. Weekly compliance for pistachio consumption ranged between 88-93%. No statistically significant treatment differences were observed for BMI, total energy or percent energy from protein. On the pistachio diet (PD), statistically significant increases were seen for percent energy from fat at weeks 3 and 4 and weeks 5 and 6 compared to weeks 1 and 2. Additionally, on the PD, a statistically significant increase for percent energy from fat was seen at weeks 5 and 6 compared to the control diet (CD). On the PD, statistically significant decreases were seen for percent energy from carbohydrate at weeks 3 and 4, and weeks 5 and 6 compared to weeks 1 and 2. Additionally, on the PD, a statistically significant decrease for percent energy from carbohydrate was seen at weeks 5 and 6 compared to the CD. On the PD, statistically significant increases were seen in energy-adjusted dietary -T at weeks 3 and 4 compared to weeks 1 and 2 (mean difference of 26%; p < 0.001), weeks 5 and 6 compared to weeks 1 and 2 (mean difference of 27%; p < 0.001). Additionally, statistically significant increases in energy-adjusted dietary -T were seen at weeks 3 and 4 on the PD compared to the CD (mean difference of 21%; p < 0.001) and at weeks 5 and 6 on the PD compared to the CD (mean difference of 24%; p < 0.001). On the PD, a statistically significant increase was observed for post intervention cholesterol-adjusted serum -T (mean difference of 26%; p < 0.001) compared to pre-intervention value. For the intervention group, a Pearson correlation was calculated for the change in energy-adjusted -T intake between weeks 1 and 2 and weeks 5 and 6 and the change in cholesterol-adjusted serum -T pre- and post intervention (r =.373; p =.025). Thus, consumption of pistachios can lead to an increase in serum levels of -T. Pistachios could be incorporated into dietary strategies designed to reduce the risk of lung cancer.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B3.

Abstract PR-03: Genetic variations in microRNA biogenesis genes as predictors for risk of second primary tumor (SPT) and/or recurrence in patients with early-stage head and neck cancer

Thu, 07 Jan 2010 13:54:29 PST

Second primary tumors (SPTs) and local-regional recurrence negatively impact the prognosis of patients with curatively treated early-stage head and neck cancer. Genetic variations in microRNA (miRNA) biogenesis genes have been found to be associated with the risk of multiple solid tumors. Thus, we hypothesized that these variations were also associated with the risk of SPT/recurrence in patients with early-stage head and neck cancer. We performed a nested case-control study including 150 early-stage head and neck cancer patients with SPT/recurrence and 300 patients without SPT/recurrence. We genotyped 71 tagging and potentially functional single nucleotide polymorphisms (SNPs) from eight miRNA biogenesis pathway genes (RNASEN, DGCR8, DICER1, EIF2C1, DDX20, GEMIN4, RAN, XPO5). Seven SNPs in RNASEN, one in XPO5, and one in RAN were significantly associated with the risk of SPT/recurrence. The most significant SNP was rs7735863, an intronic SNP in RANSEN. The variant-containing genotypes of this SNP were associated with a 1.72-fold increased risk (95% confidence interval [CI], 1.16–2.57; P=0.0076). A combined analysis showed that compared with the patients without any unfavorable genotypes, the SPT/recurrence risk was increased 1.50- (95% CI, 1.02–2.22) and 2.69-fold (95% CI, 1.59–4.53) for those with one and two unfavorable genotypes, respectively (P for trend<0.001). Survival tree analysis further identified potential higher-order interactions and categorized the study subjects into different risk groups. Compared to the low-risk group with an event-free median survival time (MST) over 96 months, patients in the high-risk group had a 5.02-fold increased risk (95% CI, 2.70–9.31; P=3.20x10^–7) and an event-free MST of 31.4 months (log rank P=1.25 – 10^–7). Our results suggest that genetic polymorphisms within the miRNA biogenesis pathway may be used individually and jointly to predict the risk of SPT/recurrence of early-stage head and neck cancer patients.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):PR-03.

Abstract A4: SNP-SNP interaction and nongenetic risk factors combine to identify lung cancer susceptibility: Validation in a prospective study

Young, R., Hopkins, R., Hay, B., Gamble, G. — Thu, 07 Jan 2010 13:54:00 PST

Introduction: Key risk indicators for lung cancer include a smoking history, genetic factors, increasing age, family history and impaired lung function (COPD). In a case-control study, 20 genetic markers associated with lung cancer were combined with non-genetic risks to derive a lung cancer susceptibility score (LCSS). The aim of this prospective follow up study was to compare the LCSS in a cohort of very high risk smokers, with and without lung cancer.

Methods: A cohort of 728 high risk individuals (smoker/ex-smokers, >40 yrs old, >20 pack years, with spirometric confirmed COPD) were recruited and followed for a mean of 5 years. All volunteers underwent spirometry, completed a modified ATS respiratory questionnaire and gave blood for DNA. These volunteers were recruited from the community (N=420) and a COPD outpatient clinic (N=308). To date, we have identified 53 cases of lung cancer (histology confirmed) in this cohort (24 community and 28 clinic). The 20 SNP panel was genotyped using the iPLEX system. Each subjects' genotypes were combined, in a predefined algorithm, to derive the lung cancer susceptibility score.

Results: COPD patients subsequently diagnosed with lung caner were comparable to those with no lung cancer for age, gender, smoking exposure. The mean LCSS, was higher in those who developed lung cancer than those who did not (LCSS 7.0 vs 5.7, P=0.06), and significantly higher than those recruited from the community with mild-moderate COPD (LCSS 7.0 vs 4.7, P<0.001). The performance characteristics of the LCSS reported here, confirms its utility in high risk smokers, to target lung cancer screening and/or diagnostic approaches (using molecular, cytological and/or radiological based tools).

Conclusion: We show, in a prospectively recruited high risk cohort, that our LCSS identifies those with mild-moderate COPD at greatest risk of lung cancer. Such a group might benefit from aggressive screening/diagnostic approaches, so that their lung cancer is diagnosed in stage 1 when survival has been shown to be dramatically improved.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A4.

Abstract B4: Health-related and sociocultural correlates of physical activity among an African American cohort

Cogbill, S. — Thu, 07 Jan 2010 13:54:13 PST

Background: Participation in physical activity has been shown to have many health benefits including contributions to the reduction in rates of all-cause morbidity/mortality and helps in the prevention of many chronic diseases, including cancer. Despite these known health benefits, national data indicates that adherence to recommendations are low, with the rates being the lowest among African Americans. Socio-demographic characteristics, having a history of co-morbid conditions, and physician recommendation to exercise have all been shown to influence participation. However, few studies have measured the impact of socio-cultural factors. This presentation identifies demographic, health influenced, and socio-cultural factors that have been found to play a role in physical activity participation in a cohort of African Americans.

Method: African American men and women (ages 45–75), residing in a Midwest metropolitan area, participated in a two-armed randomized community intervention trial (N = 661). Each participant completed a baseline survey that contained questions regarding physical activity participation, demographic, and health related characteristics. The survey also included questions about socio-cultural (SC) factors found to be relevant in previous research with this population. Baseline data were analyzed to determine the rate of participation in physical activity as well as the rate of adherence to guidelines (i.e., 30+ minutes of moderate physical activity five or more days per week, or vigorous physical activity for 20+ minutes three or more days per week). Additional analyses examined demographic, health-related (personal history of chronic diseases and physician recommendation), and SC characteristics (mistrust, collectivism, humanism, social desirability, and nationalism) to determine their relative influence on physical activity participation and adherence to guidelines.

Results: The rates of physical activity participation (83.6%) and adherence (52%) were slightly higher for this cohort than previously reported. Bivariate analyses indicated that being married, having more than a high school education, having an income of more than $40,000, being employed, receiving a physician recommendation to exercise, and having chronic disease were significantly associated with physical activity participation and adherence (p<0.05). Additionally, being mistrustful of the medical establishment and identifying with a collectivist viewpoint were also important. Logistic regression analyses indicated that receiving a physician recommendation to exercise, having high mistrust of the medical establishment and identifying with a collectivist viewpoint significantly influenced physical activity participation and adherence after adjustment (p<0.05). These findings may provide new strategies for increasing physical activity among African Americans, which can ultimately result in improvements in cancer prevention and control for this population.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B4.

Abstract PR-04: Blood lipid and lipoprotein levels and the risk of colorectal cancer in the European Prospective Investigation into Cancer and Nutrition

Thu, 07 Jan 2010 13:54:29 PST

Background: Blood lipids and lipoproteins may affect colorectal cancer (CRC) risk, but results are inconsistent. We examined the relation between serum levels of total cholesterol, high density lipoprotein (HDL), low density lipoprotein, triglycerides, apo lipoprotein A–I (apoA), apo lipoprotein B and the incidence of CRC.

Methods: A nested case-control study was conducted within the European Prospective Investigation into Cancer and Nutrition (EPIC). A total of 1238 first primary incident colorectal cancer cases were matched to 1238 controls by age, gender, center, time of blood collection and fasting status. Serum levels were quantitatively determined by a colorimetric method. Conditional logistic regression models were used to estimate relative risks (RRs) and 95% confidence intervals (95% CI).

Results: After adjustments, levels of HDL and apoA were inversely associated with colon cancer risk (RR for one standard deviation increase of 0.43 mmol/L in HDL and 0.32 g/L in apoA (95% CI) = 0.78 (0.68–0.89); p<0.01 and 0.82 (0.72–0.94); p<0.01, respectively) and with distal cancer risk (0.79 (0.65–0.96); p=0.02 and 0.83 (0.69–1.01); p=0.07, respectively). Although only slightly weaker, associations with proximal colon cancer risk were not statistically significant (0.82 (0.65–1.03); p=0.09 and 0.86 (0.68–1.07); p=0.18, respectively). Inclusion of other biomarkers or exclusion of the first 2 years of follow-up did not influence the association between HDL and colon cancer risk. No association was observed for rectal cancer risk.

Conclusion: These findings suggest that high HDL levels may decrease colon cancer risk. The mechanism behind this association should be further investigated.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):PR-04.

Abstract A5: A pilot study of circulating and intrabreast tissue estrogen levels among postmenopausal BRCA1/2 mutation-positive women

Loud, J. T., Gierach, G. L., Xu, X., Veenstra, T. D., Greene, M. H., Gail, M. H. — Thu, 07 Jan 2010 13:54:00 PST

Background: Increasing evidence suggests that BRCA1-related breast cancers may be a consequence of genotoxic variants of hormonal carcinogenesis rather than the physiological properties of ovarian hormones. Catechol estrogens, 2-OHE₁, 2-OHE₂, and 4-OHE₁ and the 16 -hydroxlyated estrogens are strong promoters of breast carcinogenesis. In BRCA1 mutation carriers, estrogens may elevate risk by increasing genomic instability within the background of impaired DNA repair function (Y Hu et al., Oncogene, 2005). Currently, the influence of BRCA2 on transcriptional activity of ER is unknown. The relationship between circulating estrogen metabolites (EM) and EM in breast tissue (e.g., in nipple aspirate fluid (NAF) and ductal lavage supernatant (DLS) is not well-established in either BRCA1/2 mutation carriers or in non-carriers.

Methods: We conducted a cross-sectional study of EM in serum, NAF, and DLS among postmenopausal (i.e., spontaneous amenorrhea for ≥12 months or bilateral oophorectomy) BRCA1/2 carriers ages 31 to 57 enrolled in the Clinical Genetics Branch's Breast Imaging Study. Serum, NAF and DLS were collected (using standard methods) at the same visit, but both NAF and DLS could not always be collected from each participant. Total EM (conjugated and free forms of estrone (E₁), estradiol (E₂), estriol (E₃) and up to 12 EM were measured in paired NAF and serum samples (n=19 women) and paired DLS and serum samples (n=25 women) using a novel quantitative liquid chromatography-tandem mass spectrometry method previously validated for serum (X Xu et al., Anal Chem, 2007). Spearman's correlation coefficients were calculated to examine the strength of the relationship between serum and tissue-specific EM.

Results: The intraclass correlation coefficients (ICC) for EM assessed in replicate specimens demonstrated excellent reproducibility for all specimen types (ICCs ranged from 0.98–0.99 for EM measured in individuals with replicate NAF, DLS, and serum specimens). Total (conjugated plus free) levels of circulating serum EM were strongly and positively correlated with tissue-specific EM measured in NAF (E₁, r=0.99, p<0.0001; E₂, r=0.73, p=0.0004; E₃, 0.88, p<0.0001; 2-MeOE₁, r=0.57, p=0.01; 2-MeOE₂, r=0.44, p=0.06; 2-OHE₁, r=0.73, p=0.0004; 2-OHE₂, r=0.58, p=0.009) and DLS (E₁, r=0.97, p<0.0001; E₂, r=0.72, p<0.0001; E₃, 0.79, p<0.0001; 2-MeOE₂, r=0.42, p=0.04.

Conclusions: Our data demonstrate that EM can be detected and reliably measured in novel breast tissue-derived biospecimens (i.e., NAF and DLS). Further, our data suggest that circulating EM are strongly and positively correlated with tissue-specific EM measured in NAF and DLS among postmenopausal BRCA1/2 mutation carriers. Correlations between EM and mammographic density will be presented (analyses ongoing). Our pilot data will guide future larger studies designed to determine whether circulating levels of EM may be used to predict intra-breast levels, using existing samples from a more diverse group of women with varying degrees of breast cancer risk and measured mammographic density, a potent breast cancer risk factor. Ultimately, we hope to identify key EM correlates of mammographic density for use as surrogate biomarkers of breast cancer risk and risk modulation measures related to chemoprevention and lifestyle modification.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A5.

Abstract B5: Psychosocial mechanisms for explaining the relationship between physical activity and fatigue in breast cancer survivors

White, S. M., McAuley, E., Rogers, L. Q., Courneya, K. S. — Thu, 07 Jan 2010 13:54:13 PST

Fatigue is one of the most commonly reported and enduring symptoms experienced as a result of breast cancer treatment. One important behavior that has been identified as having the potential to reduce breast cancer related fatigue is physical activity. However, few attempts have been made to fully understand this relationship and it is not known whether physical activity directly influences fatigue or operates through other factors. The purpose of this study was to examine the role of psychosocial mechanisms, self-efficacy and depression, as potential pathways from physical activity to fatigue in a cross-sectional sample of breast cancer survivors (N=192). Participants completed measures of health status, physical activity, depression, fatigue, and self-efficacy. Data were analyzed using path analysis within a covariance modeling framework. This model proposed that that physical activity's influence on fatigue is indirect through its direct effect on self-efficacy which, in turn, has both a direct effect on fatigue and an indirect effect through depression. The hypothesized path model provided an excellent fit to the data (² = 1.48, df = 2, p =.48; SRMR = 0.02, CFI = 1.00). All of the proposed path coefficients of the hypothesized model were significant. Overall, the model accounted for 45.2% of the variation in fatigue. As a result of the robust relationship between fatigue and depression (β =.51), the analysis was re-run using a depression score which excluded items assessing "somatic and retarded activity" symptoms. The fit of the model was almost identical to the previously described model (² = 1.48, df = 2, p =.45; SRMR = 0.03, CFI = 1.00). A final analysis was conducted on the original model to test effects of for demographics (i.e., age, education, employment, income), time since diagnosis, breast cancer stage, current treatment, menopausal status, body mass index, and comorbidities on model fit and path coefficients, as well as the model components themselves. This model also was an excellent fit to the data (² = 2.10, df = 2, p =.35; SRMR = 0.01, CFI = 1.00). In general, the magnitude and direction of the hypothesized relationships were unaffected by the inclusion of the covariates in the model. Our findings suggest support for one set of psychosocial pathways from physical activity to fatigue, an important concern in breast cancer survivors. Subsequent work might replicate such associations in other survivor populations and attempt to determine whether model relations change with physical activity interventions, and the extent to which other known correlates of fatigue such as impaired sleep and inflammation can be incorporated into this model.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B5.

Abstract PR-05: Alterations in tissue autofluorescence using spectroscopy in high-risk oral lesions

Poh, C. F.Y., Wiens, E., Lane, P., Au, S., Rosin, M. P., MacAulay, C. E. — Thu, 07 Jan 2010 13:54:29 PST

High-risk oral lesions can be sometimes difficult to discriminate from reactive oral lesions, which are commonly seen within community settings. New tools need to be developed to aid in screening and early detection of high-risk lesions. The assessment of alteration in tissue autofluorescence using spectroscopy has demonstrated promising results in distinguishing cancerous from normal tissue at many organs and sites; however, there is limited information on its usage to distinguish reactive lesions (as seen by both white-light and autofluoescence imaging) from cancerous/precancerous lesions.

Objectives of this study are: 1) to collect autofluorescence spectra from normal mucosa, mucosa with high-risk histological change and those with chronic inflammation under different excitation wavelengths of light, and 2) to compare the change in tissue autofluorescence in different exciting wavelengths among these oral mucosal lesions.

Methods: Patients with high-risk oral lesions and inflammatory conditions were recruited from the Dysplasia Clinics of the BC Oral Cancer Prevention Program. Spectroscopic measurements were taken using a fiber optic probe of a Remiscope (Remicalm, LLC; Houston, TX). Three excitation wavelengths were used: 436 nm, 405 nm, and 355 nm. Percent loss of peak emission intensity (%PEI) was measured by comparing the PEI of the lesional and contralateral normal areas. Differences in %PEI between groups were compared using unpaired t-test.

Results: From June to September 2009, 102 spectroscopic measurements were recorded from 17 patients (cancer, 5; dysplasia, 6; inflammation, 6). Among these, loss of tissue autofluorescence under 436 nm, 405 nm, and 355 nm was observed in all cases. When comparing the %PEI between cancer and dysplasia groups, increased loss was seen in the cancer group at all three excitation wavelengths, especially under 355 nm and 405 nm excitations (P = 0.023 and 0.045 respectively). When comparing to the inflammation group, there is almost the same degree of loss observed between cancer and inflammation groups in all 3 excitation wavelengths. Interestingly, there is a significant difference in %PEI observed between dysplasia and inflammation group under 436 nm and 355 nm excitations (P = 0.005 and 0.022 respectively) but no statistical difference under 405 nm excitation.

Conclusions: This is the first study to use 3 different excitation wavelengths of light to examine the spectra of oral cancerous, precancerous, and specifically inflammatory oral lesions (as seen by both white-light and autofluoescence imaging). This device has shown its potential to provide an objective, sensitive approach to distinguish precancers from those commonly seen within community settings caused by chronic inflammation. (Supported by grant R01 DE17013 from the National Institute of Dental and Craniofacial Research and grant CCSRI-20336 from Canadian Cancer Society Research Institute. CFP is supported by a Clinician Scientist Award from the Canadian Institutes of Health Research and a Scholar Award from the Michael Smith Foundation for Health Research).

Citation Information: Cancer Prev Res 2010;3(1 Suppl):PR-05.

Abstract A6: Ethnic differences in risk of lung cancer associated with repair capacity for tobacco carcinogen-induced DNA adduct

Wang, L.-E, Spitz, M. R., Qiao, Y., Dong, Q., Amos, C. I., Wei, Q. — Thu, 07 Jan 2010 13:54:00 PST

Lung cancer is initiated by tobacco carcinogens-induced DNA damage, such as DNA adducts caused by benzo[a]pyrene diol epoxide (BPDE). These adducts can be removed by an efficient nucleotide excision repair. We have previously reported that DNA repair capacity (DRC) measured by the host-cell reactivation assay is associated with risk of lung cancer in non-Hispanic whites. In the recent analysis with larger sample sizes including minorities, we found that the suboptimal DRC remains associated with increased risk of lung cancer in 1730 cases and 1683 controls of non-Hispanic whites. The mean values of DRC were 8.37% ± 2.8% (SD) in the cases vs. 9.04% ± 3.1% in the controls (P < 0.0001). The odds ratio (OR) was 1.42 (95% confidence interval [CI], 1.24 – 1.64) after adjustment for age, sex, pack-years of smoking, family history of cancer, and other assay-related covariates. The similar results and risk trend have been also found in 127 Mexican-American patients with lung cancer and 176 cancer-free controls with a mean DRC of 8.38% ± 2.7% in the cases vs. 9.04% ± 3.3% in the controls, and an adjusted OR of 1.67 (95% CI, 1.00 – 2.78), although the difference in mean DRC values was borderline significant (P = 0.056) because of the relatively small sample size. However, this difference in DRC for tobacco carcinogen-induced DNA adducts was not significant in 327 African-American patients with lung cancer and 325 cancer-free controls. The mean values of DRC were 8.90% ± 3.1% in the cases vs. 8.66% ± 2.8% in the controls (P = 0.301). The adjusted OR was 0.99 (95% CI, 0.70 – 1.39). The DRC level in African-American controls was non-significantly lower than other ethnic controls (P = 0.144); however, African-American patients had significantly higher DRC than non-Hispanic white patients and Mexican-Americans patients (P = 0.053). The results further confirmed that low DRC is associated with increased risk of lung cancer in non-Hispanic whites and also provided the evidence of this association in Mexican Americans. These findings help us understand the ethnic differences in the development of lung cancer.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A6.

Abstract B6: Obesity risk in relation to quality of life: Baseline results from a worksite trial

Thu, 07 Jan 2010 13:54:13 PST

Introduction: Obesity, a risk factor for certain cancers, can also be related to reduced health-related quality of life and productivity. We examined eating physical activity behaviors, and body mass index (BMI), as predictors of health-related quality of life and productivity.

Methods: MOVE ‘M is a worksite-randomized trial targeting diet and physical activity to reduce weight gain. Secondary outcomes include Obesity and Weight Loss Quality of Life (OWLQOL) and productivity. Baseline data collection occurred from 2006–2008, and data were analyzed in 2009.

Results: Baseline data were analyzed for individual-level associations using linear mixed models. Since gender was found to be an effect modifier, data were analyzed separately for men (n=288) and women (n=281). BMI was negatively associated with OWLQOL in both women (p<0.001) and men (p<0.001). The linear effect estimate for OWLQOL score associated with one category increase in BMI was 32% (95% CI: 27%, 37%) for women and 12% (95% CI: 8%, 17%) for men. Physical activity was associated (p=0.007) with OWLQOL only in women. Eating while doing another activity was negatively associated with OWLQOL scores only in men (p=0.0003) and with productivity only in women (p=0.004).

Conclusion: Our results suggest obese persons, particularly women, experience diminished OWLQOL. If longitudinal analyses confirm these findings, there may be additional work-related and general health benefits from reducing weight and increasing physical activity.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B6.

Abstract PR-06: Upregulation of microRNA-21 (miR-21) in human bronchial epithelial cells chronically exposed to 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) plus nicotine and modulation of these effects by diindolylmethane

Kassie, F., Jarcho, M., Endalew, A. — Thu, 07 Jan 2010 13:54:29 PST

MicroRNAs (miRNAs) represent a class of naturally occurring small noncoding RNA molecules that regulate genes by either inducing mRNA degradation or inhibiting translation. The expression of miRNAs is deregulated in several cancers, including lung cancer. However, most studies have been carried out using full-blown cancer tissues and the regulation of miRNAs during early-stage tumorigenesis is unknown. In the present study, we used an in vitro model of lung tumorigenesis to assess the effect of chronic treatment with tobacco compounds on the expression of miR-21, one of the most deregulated miRNAs in lung cancer, in human bronchial epithelial cells (HBEC). Freshly prepared NNK (10 µM) and nicotine (10 µM) were added to the culture media containing NHBC every 3 days for 3 weeks. Beginning the second week of NNK plus nicotine treatment, the dietary chemopreventive agent diindolylmethane (DIM) was added, every 3 days, to the culture media until the termination of the study. Then, the cells were harvested, RNA prepared and the expression level of miR-21 and its target genes PDCD4 and RECK were analyzed by QRT-PCR. Levels of PDCD4 and RECK were also examined by Western immunoblotting. NNK plus nicotine treatment significantly elevated miR-21 levels but markedly decreased expression of PDCD4 and RECK at both gene and protein levels. The effect of the tobacco compounds on miR-21 as well PDCD4 and RECK was reversed by treatment with DIM. This study shows that miR-21 levels are deregulated beginning the early phase of lung tumorigenesis and miR-21 is a valuable target for chemopreventive agents.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):PR-06.

Abstract A7: Using haplotype analysis to find significant associations between genes and Hodgkin's disease

D'Amelio, A. M., Monroy, C., El-Zein, R., Etzel, C. — Thu, 07 Jan 2010 13:54:01 PST

Background: With increasing amounts of genes available for study, more opportunities are available to discover key associations between genetic factors and disease. In a previous study on Hodgkin disease, we observed powerful positive associations between genes on chromosomes 3 and 19. In this study, we expanded the previous analyses to include 62 single nucleotide polymorphisms (SNPs) in DNA repair and inflammation pathway genes located throughout the genome and evaluated possible associations for Hodgkin disease by inferring haplotypes at the individual gene level.

Methods: Genetic and epidemiological data were obtained from a case-control study conducted at M.D. Anderson Cancer Center between 1987 and 1992 including 200 cases and 220 controls. Haplotypes were initially inferred with Haploview using linkage disequilibrium plots, and differences in haplotypes between cases and controls were determined with PHASE. Linear modeling with haplotypes, through both joint and separate effects haplotype modeling, with sex, race, smoking status, and age as confounders, were conducted with Haplo.stats. A joint-effects linear model allows each haplotype to be compared to the most frequent haplotype. A separate-effects linear model compares a haplotype to all of the other haplotypes possible for study.

Results: With the joint effects haplotype model, some significant haplotype associations with Hodgkin disease were observed with DNA repair gene XPC on chromosome 3 and inflammation pathway gene ILR4 on Chromosome 16. For DNA repair gene XPC, susceptible associations with Hodgkin disease were discovered with the use of an additive genetic model with haplotype CT from SNPs rs2228001 (XPC 499 A>C) and rs2228000 (XPC 939 C>T) (OR = 1.49, 95% CI = 1.03–2.16) and a dominant genetic model with the same haplotype (OR = 1.75, 95% CI = 1.15–2.13). For inflammation pathway gene ILR4, protective associations with Hodgkin disease were discovered with the use of an additive genetic model with haplotype TC from SNPs rs1805012 (XPC 499 T>C) and rs1805015 (XPC 939 T>C) (OR = 0.63, 95% CI = 0.33–0.99) and a dominant genetic model with the same haplotype (OR = 0.48, 95% CI = 0.26–0.88). The separate effects haplotype model also highlighted associations between haplotypes and Hodgkin disease on these same genes. Other significant associations between haplotypes and Hodgkin disease were observed on chromosomes 5 with inflammation pathway gene IL4 and chromosome 19 with DNA repair gene.

Conclusions: The basis for haplotype analysis to analyze the effects of linked SNPs associated with Hodgkin disease has been demonstrated. Furthermore, the interactions between specific SNPs in both the inflammation and the DNA repair pathway have been shown to play an important role in possible Hodgkin disease development. By targeting specific aspects of the genome that show either an increase or decrease in Hodgkin risk, identification of high risk individuals could be achieved.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A7.

Abstract B7: Use of risk assessment services and predictive genetic testing (PGT) for hereditary gastrointestinal (GI) cancers: How do men and women differ?

Thu, 07 Jan 2010 13:54:13 PST

Background: Uptake of risk assessment and PGT for hereditary GI cancer risk has lagged far behind that of the hereditary breast-ovarian cancer syndrome and BRCA1/2, despite the parallel clinical availability of genetic services for hereditary GI cancers, the proportion of patients with incident colorectal cancers who demonstrate familial risk (~ 1 in 3), and the prevalence of Lynch syndrome associated mismatch repair gene mutations among incident colorectal cancers (~ 3–5%). The bulk of data on perceptions of PGT have focused on women considering BRCA1/2 testing for personal and/or familial risk estimation. Studies in men are less plentiful, and have often focused on men's opinions about PGT for prostate cancer risk, although clinical PGT for hereditary prostate cancer is not currently available. Individuals enrolled in a high-risk GI cancer registry represent a unique population in which important differences in perceptions of PGT between men and women may be directly examined to shed light on barriers to risk assessment and PGT, and cancer prevention services in general, that may differ by gender.

Methods: The GI Tumor Risk Assessment Program (GI-TRAP) registry at Fox Chase Cancer Center enrolls individuals at increased risk for GI cancers because of a suggestive personal or family history. At enrollment and prior to risk education and counseling, participants are asked to complete a detailed personal and family history and a questionnaire examining screening practices and psychosocial aspects of hereditary cancer risk. The GI-TRAP registry currently contains information collected from members of 269 families.

Results: Women (n=293) participants outnumbered men (n=105) almost 3 to 1, were younger (47.0 vs 50.8 yrs)(p=0.01), and were less likely to work full-time (39.9% vs 59.0%)(p<0.001). The most common reasons for wanting testing in both groups were to guide screening (91.4% men, 95.7% women)(p=0.11) and learn children's risks (75.8% men, 83.7% women)(p=0.09). Women were more likely to want testing as a global means to "take better care of myself" (p=0.004), and were more concerned about personal (p=0.05) and family (p=0.04) emotional reactions to testing results, as well as the possible impact of testing on health insurance (p=0.06). Men were more willing to pay for genetic testing ("I plan to get genetic testing even if I have to pay")(p=0.02) and were more willing to pay larger sums for testing ("I would pay equal to or over $1000 for genetic testing")(p=0.04).

Conclusions: Compared to women, overall fewer men obtain available risk assessment services for hereditary GI cancers. Men seek risk assessment for similar reasons to women, but express lower concern for out-of-pocket costs or adverse personal and familial emotional reactions to testing results. Efforts to make cancer risk assessment services more visible and available to men and working individuals (e.g., expanded clinical hours, on-site education/counseling at places of employment, health clubs, etc) may help to increase the identification of high-risk individuals who would benefit from tailored GI prevention education, genetic counseling, and PGT.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B7.

Abstract PR-07: Skin cancer concerns and genetic risk information seeking in primary care

Hay, J., Kaphingst, K., Li, Y., Baser, R., Alford, S. H., McBride, C. — Thu, 07 Jan 2010 13:54:29 PST

Skin cancers are among the most rapidly increasing cancers in the United States. The most serious form, melanoma, is relatively common in younger adults and has a high mortality rate if it becomes metastatic. Growing evidence from genome-wide association studies is identifying genetic variants associated with skin cancer risk. Accordingly, it is being suggested that genomic testing for these variants could enable personalized feedback of susceptibility to skin cancer as an innovative approach to motivate adoption of preventive behaviors. Little is known about the receptivity of healthy adults to genetic risk information for common diseases such as cancer. We investigated whether cognitive factors (worry and perceived skin cancer risk), family factors (family health history awareness, family or personal cancer history, family constellation and social influences on health), behavioral factors (sunburn and sunscreen use history), and level of general health information-seeking relate to perceived importance of learning about how genes affect personal health risks. These research questions were examined using baseline assessment data from the Multiplex Initiative, a primary-care based study examining interest and uptake of genetic susceptibility testing for eight common diseases in a large Midwestern health maintenance organization. The sample included 1959 members, ages 25–40, who had not been diagnosed with any of the eight conditions on the genetic test. About 53% of participants were female; 37% were white and 53% black. Most (75%) had at least some college education. Average level of perceived importance of learning about genes was high (X=5.55; 1–7 scale). To highlight interactions between covariates, we used recursive partitioning classification and regression trees (RPART) to identify predictors of perceived importance of learning about genes among white and black respondents. In whites, the tree correctly classified 79% of the participants, such that those participants who perceived that others close to them wanted them to learn more about keeping healthy, were highly worried about skin cancer, and reported lower perceived skin cancer risk were most likely to endorse high levels of perceived importance of learning about genes; other variables did not substantially improve model accuracy. Findings were similar for blacks. This study indicates that the perceived investment of family and friends regarding health-focused information seeking may be a primary motivator for learning about how genes affect health, and that investigation of actual and perceived social support and social influences may improve our understanding of how cognitive and information seeking processes relate to interest and uptake of genetic information in primary care settings.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):PR-07.

Abstract A8: Cytogenetic evaluation of human individual radiation sensitivity with the purpose of primary prevention of radiogenic cancer

Ryabchenko, N. — Thu, 07 Jan 2010 13:54:01 PST

Background: Rising of cancer incidences in population of Ukraine is connected with the increasing of cancerogenic loading where ionizing radiation has been recognized as a strong cancer causing agent. Today variations in radiation sensitivity between individuals are shown to be genetically determined and connected with the effectiveness of cell signaling system function after exposure to damaging agents. Recent reports have suggested that elevated chromosome aberration yields observed following radiation exposure of peripheral lymphocytes in G2 phase of cell cycle caused by the impaired DNA repair and hereditary predisposition to cancer. The goal of the presented study was to evaluate chromosomal sensitivity of lymphocytes of healthy individuals on the basis of the modified G2-test.

Materials and Methods: Test-system of human peripheral blood lymphocytes (PBL) of 110 healthy donors with the next metaphase analysis of chromosomal aberrations (chromatid breaks) was used. Test -irradiation of cell cultures was carried out at 1,5 Gy in the late G2-stage. Cells were analyzed in the first mitosis.

Results: The obtained cytogenetic data has revealed high interindividual variability in the levels of radiation induced chromatid breaks (CV = 24%). It was shown that distribution of the examined cytogenetic parameter in the group did not correspond to normal distribution and had bimodal character. Application of variation statistics' methods has revealed existence of two subgroups of donors - with "normal" and "increased" (11,6 % of the group) radiation sensitivity of lymphocytes on chromosomal level.

Taking into account correlations of high radiation-induced genome instability of human somatic cells with cancer predisposition it is competent to relate these individuals with the group of increased radiogenic cancer risk. Application of cytogenetic examinations on the basis of G2-assay is recommended for the formation of groups with the increased radiogenic cancer risk and promotes the efficiency of primary cancer prevention in the cohorts of occupationally exposed individuals.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A8.

Abstract B8: Understanding suboptimal HPV vaccine uptake among low-income ethnic minority girls in Los Angeles

Bastani, R., Glenn, B. A., Tsui, J., Singhal, R. — Thu, 07 Jan 2010 13:54:13 PST

Introduction: The recent availability of an HPV vaccine represents a landmark breakthrough in the primary prevention of cervical cancer, which is a major cause of morbidity and mortality in the United States and world wide. Vaccination is one of the most successful and least costly of all public health interventions but to derive population benefit it is critical to achieve wide utilization, particularly among the highest risk groups. However, in the United States, there is considerable skepticism regarding the rapid deployment of a new technology targeting young girls that is related to a sexually transmitted infection. The purpose of this study, therefore, was to assess vaccine uptake and correlates among low income, ethnic minority girls in Los Angeles.

Methods: This study was a collaboration between UCLA and the Los Angeles County Office of Women's Health (OWH), which operates a telephone hotline to provide health information and service referrals to low-income, ethnic minority women in Los Angeles. Telephone interviews were administered, through the hotline, in five languages (English, Spanish, Mandarin, Cantonese, Korean) to mothers of girls aged 9 to 18 years, and assessed: demographics, HPV awareness, acceptance, knowledge, attitudes, barriers, and vaccine receipt in the age-eligible girls.

Results: A total of 390 women (54% Latina; 20% Chinese; 13% Korean; 8% African American; 6% other) were interviewed from January–July 2009, and ethnic differences were observed in many of the variables. Overall, 64% of respondents reported having heard of the HPV vaccine, but the rate was only 42% among Koreans. About 30% of girls had received at least one dose of the HPV vaccine (33% Latinas; 22% Chinese; 26% Koreans; 26% African Americans, 32% "other"). Ethnic differences were also observed in perceived risk of contracting HPV, perceived severity of HPV, and perceived vaccine effectiveness. Barriers cited by mothers of unvaccinated girls included concern over side effects, cost and having insufficient information to make a decision. Only 28% reported knowing where they take their daughter to get the vaccine with lower rates among Chinese (19%) and Koreans (16%) compared to African Americans (29%), and Latinas (35%). Similarly, only 28% of women said they had enough information to make a decision about vaccination with fewer Chinese (17%) and Koreans (14%) reporting this versus Latinas (31%) and African Americans (56%). In bivariate analyses the following factors predicted increased likelihood of vaccination: older age of daughter, having a usual source of care, holding positive attitudes towards vaccination, higher perceived risk of HPV, higher perceived effectiveness of the vaccine, higher perceived severity of HPV, and belief that girls should be vaccinated at a younger age. Only three factors were significant in multivariate analyses: older age of daughter, belief that girls should be vaccinated at a younger age, and higher perceived vaccine effectiveness.

Conclusion: In general, vaccination rates in our sample were comparable to state and national estimates. However, significant gaps in knowledge and awareness were observed and ethnic differences were striking. Information from this study will provide valuable guidance for targeting and tailoring interventions to increase HPV vaccine uptake in high risk groups.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B8.

Abstract PR-08: Body mass index and breast cancer outcomes in older breast cancer survivors

Bosco, J. L.F., Silliman, R. A. — Thu, 07 Jan 2010 13:54:29 PST

Obesity may increase the risk of breast cancer and decrease survival in postmenopausal women through higher levels of circulating estrogen. The mortality risk is greater in younger women, but studies of women ≥ 65 years are limited. Consenting women ≥ 65 years at incident diagnosis of stage I (tumor ≥ 1 cm), stage II, or stage IIIA primary breast cancer from Los Angeles, Minnesota, North Carolina, or Rhode Island were interviewed by telephone 3 months (baseline) after their definitive surgery (N=658) and were followed annually for 9 years unless death, loss to follow-up, or refusal to continue participation occurred. BMI was calculated using weight (kilograms [kg]) and height (meters [m]) reported at baseline (BMI 25–29 kg/m² = overweight; BMI ≥ 30 kg/m² = obese). Women with a healthy BMI (< 25 kg/m2) comprised the reference group. Recurrence was collected during follow-up interviews. Death was confirmed by a Social Security Death Index search through March 2009 and date and cause of death were collected from the National Death Index through 2004. Demographic characteristics (age, race, marital status, education, geographic location, and Charlson Comorbidity Index [CCI]) were collected at baseline. Breast cancer tumor (stage, histologic grade, estrogen receptor expression) and treatment (primary therapy, adjuvant chemotherapy receipt, adjuvant tamoxifen receipt) characteristics were collected from medical records. Of our cohort, 34% were overweight and 21% were obese (mean BMI, 25.7 kg/m²). The majority of overweight women were 70–74 years old (29%), had a CCI of 0 (62%), and completed college or higher (53%); obese women were mostly 65–69 years (34%), had a CCI of 2 (13%) and only completed up to high school (40%). Women who were overweight (Odds Ratio [OR]=1.5; 95% Confidence Interval [CI]=0.8, 2.7) or obese (OR=1.6; 95% CI=0.8, 3.1) had an increased the risk of recurrence compared with women with a healthy BMI. Being overweight was not associated with breast cancer-specific mortality or allcause mortality. Obese women had nearly a twofold increased risk of dying from breast cancer (OR=1.9; 95%CI=0.7, 5.0); obesity was weakly associated with the risk of dying from any cause (OR=1.2; 95%CI=0.7, 1.8). Weight at baseline and 6 years later were consistently reported by the women in our study. Since women do not tend to overestimate their weight, our results conservatively estimate the effect of obesity on breast cancer outcomes. Unlike many previous studies, we had detailed information regarding primary and adjuvant treatment, which are important in estimating the risk of breast cancer recurrence and mortality. Although our data are compatible with a 20–30% decreased risk of breast cancer outcomes, our findings suggest higher body mass after breast cancer diagnosis is associated with negative outcomes in older women. Achieving or maintaining a healthy BMI after definitive surgery may improve breast cancer prognosis.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):PR-08.

Abstract A9: Genetic polymorphisms in the vitamin D receptor gene and androgen pathway gene SRD5A2 may be informative of prostate cancer risk in African American men undergoing prostate cancer screening

Hughes, L., Ruth, K., Giri, V. N. — Thu, 07 Jan 2010 13:54:01 PST

Background: Men with a family history (FH) of prostate cancer (PCA) and African American (AA) men are at 2 to 7-fold increased risk for the disease. Assessing risk for PCA in these high-risk men has been challenging due to the lack of available genetic testing. The vitamin D and androgen pathways have been studied for years for association to prostate cancer risk with single nucleotide polymorphisms (SNPs) in the vitamin D receptor (VDR) gene and genes encoding enzymes involved in testosterone biosynthesis found to have no substantial association to prostate cancer risk. However, a recent study found an interaction between the FokI SNP in VDR and the V89L SNP in SRD5A2 (converts testosterone to dihydrotestosterone) in non-Hispanic white men. In addition, in Hispanic white men, the V89L SRD5A2 polymorphism and the CDX2 VDR SNP was associated with prostate cancer. We evaluated these particular genetic variants in VDR and SRD5A2 for association to prostate cancer and time to prostate cancer diagnosis in high-risk men enrolled in the Prostate Cancer Risk Assessment Program (PRAP)- a screening and research program with 60% African American participation.

Methods: Eligibility for PRAP includes men ages 35–69 years with one first degree relative with PCA, two second degree relatives with PCA on the same side of the family, any AA man regardless of FH of PCA, or men with BRCA1/2 mutations. Current criteria for biopsy include PSA > 2.0 ng/mL, PSA 1.5–2.0 ng/mL with free PSA < 25%, any abnormality on digital rectal examination, or PSA velocity of 0.75 ng/mL/year. All biopsies are 12-core under transrectal ultrasound guidance with additional cores taken at physician discretion. Genotyping of SRD5A2 V89L and VDR CDX2 was performed using the Taqman® SNP Genotyping Assay (Applied Biosystems) per manufacturer's instructions. Pyrosequencing methods were used for the FokI SNP in VDR as Taqman assays did not produce reliable results. Standard statistical methods were used to determine allele and genotype distributions by race. Cox models were used to determine time to PCA diagnosis.

Results: 661 PRAP men had genotype data available for FokI and V89L, while 380 men had genotype data for CDX2 and V89L. Among 236 AA men with at least one follow-up visit included in the FokI-V89L analysis, a significant interaction was seen between FokI and V89L genotypes after adjusting for age and PSA at entry (p=0.01). Hazard ratio estimates for AA men with the FokI CC genotype and V89L LV/LL genotypes vs. VV was 2.51 (95% CI 1.07–5.90). No interaction was seen between FokI and V89L genotypes among 194 Caucasian men, where FokI genotype alone was found to have a significant association to PCA (Hazard Ratio for FokI TT/CT vs CC = 0.29, 95% CI 0.14–0.62). No significant association to PCA was seen for CDX2 either alone or in combination with V89L for AA and Caucasian men in this analysis.

Conclusions: FokI CC in VDR and V89L LV/LL in SRD5A2 appear to be informative of time to PCA diagnosis and risk for PCA in AA men undergoing PCA screening. FokI TT/CT genotype appears to have a protective effect in Caucasian men for PCA. Further study is warranted.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A9.

Abstract B9: Geographic disparity in HPV vaccination among girls in six U.S. states

Pruitt, S. L., Schootman, M. — Thu, 07 Jan 2010 13:54:13 PST

Introduction: The human papillomavirus (HPV) vaccine was approved by the Food and Drug Administration in 2006. Since that time, limited research has examined HPV vaccine uptake among adolescent females and no studies have examined the role of disparities in HPV vaccination. The purpose of this study is to examine geographic disparity in the prevalence of HPV vaccination and to examine individual-, county-, and state-level correlates of vaccination.

Methods: Three-level random intercept logistic regression models were fitted to data from 1,709 girls aged 13–17 living in 6 U.S. states using 2008 Behavioral Risk Factor Surveillance System and 2000 U.S. Census data.

Results: Overall, 34.4% of girls were vaccinated. Significant geographical disparity across states (Var: 0.134 SE: 0.065) and counties (Var: 0.146 SE: 0.063) was present, which was partially explained by state- and county-level poverty rates. Independent of individual-level factors, poverty had differing effects at the state- and county-level: girls in higher poverty states were less likely while girls in higher poverty counties were more likely to be vaccinated. Household income demonstrated a similar pattern to that of county-level poverty: compared to girls in the highest income families, girls in the lowest income families were more likely to be vaccinated.

Conclusions: The results of this study suggest geographic disparity in HPV vaccination and area-level effects of poverty that have not previously been studied. The higher odds of vaccination among girls living in higher poverty counties and low income families may indicate the success of publicly-funded vaccination efforts targeting the underserved or a bias against vaccination among higher income groups. Overall vaccination rates continue to be sub-optimal however, and future research is needed to examine the impact of state- and local-area policies and to increase vaccination among eligible girls.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B9.

Abstract PR-09: Genetic variations in the sonic hedgehog pathway and clinical outcomes in bladder cancer

Thu, 07 Jan 2010 13:54:29 PST

The sonic hedgehog (Shh) pathway plays an important role in embryonic development and stem cell maintenance. Abnormal activation of Shh pathway has been implicated in the development of various cancers, and also in the progression to metastatic disease. We hypothesized that genetic variations in the Shh pathway may affect bladder cancer (BC) patients' clinical outcomes. We evaluated the association of 151 SNPs in nine Shh genes in a follow-up study of 738 bladder cancer patients for recurrence and progression risk in superficial BC patients, and survival in muscle-invasive and metastasis (MiM) BC patients. In superficial BC patients, GLI2 variants rs11685068 (HR: 2.12, 95% CI: 1.44–3.12) and rs7605011 (HR:1.94, 95% CI: 1.33–2.85) were significantly associated with higher recurrence risk. Individuals with rs11685068 (median survival time (MST): 7.3 months, Log-Rank P: 0.004) and rs7605011 (MST: 7.6 months, Log-Rank P: 0.002) variant alleles had shorter recurrence-free median survival time compared to patients with wild-type genotypes (MST: 16.7 months). In the subgroup receiving Bacillus Calmette-Guérin treatment, GLI3 variants rs6463089 (HR: 2.30, 95% CI: 1.44–3.66) and rs3801192 (HR: 2.57, 95% CI: 1.48–4.46) were significantly associated with higher recurrence risk and shorter recurrence-free survival durations. We also explored the cumulative effect of multiple SNPs and higher-order gene-gene interactions in modulating the recurrence. No significant associations were observed in the progression and survival analysis after correcting for multiple testing. This is the first study to evaluate the role of germline genetic variations in Shh pathway as predictors of bladder cancer outcomes. These findings warrant further replication in independent populations to identify BC patients at a high risk for a poor outcome and prognosis.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):PR-09.

Abstract A10: Insulin resistance's effect on PSA level for prostate cancer screening

Park, J., Cho, B. — Thu, 07 Jan 2010 13:54:01 PST

Introduction: Previous studies showed that BMI decreased serum PSA level. Insulin resistance in obesity is suggested one of reasons. The negative association between BMI and PSA level may be partially due to low testosterone concentration caused by obesity-related hormonal disturbances (decrease of sex-hormone binding globulin and increase of aromatase and IR)

Objective: To examine the effect of homeostasis model assessment of insulin resistance (HOMA) index on PSA level after adjusting prostate volume(PV) effect in a screening population.

Design: We performed multivariate linear regression and ANOVA to assess potential influencing factors in a cross-sectional study of 30- to 80-year-old Korean men who underwent routine checkups from 2004–2008 (n=3,320).

Main Outcome Measures: Associations between factor variables (BMI, HOMA Index, PV) and PSA level assessed by trends tests by multivariate linear regression and/or ANOVA.

Results: PSA level was negatively associated with BMI before (P for trend <.01) and after (P for trend by quartile <.05 for all) PV stratification, but not associated with HOMA index before (P for trend >.05) and after (P for trend by quartile >.05 for all) PV stratification.

Conclusions: BMI has negative effect on PSA level irrespective of PV stratification, but IR had no association. Hemodilutional effect by obesity may be main cause of BMI's negative association on PSA level.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A10.

Abstract B10: Colorectal cancer and screening knowledge: A focus group investigation

Fernandez, N. P., Arms, D., Guillen-Gomez, L. I., Morera, O. F. — Thu, 07 Jan 2010 13:54:13 PST

Aim: To explore Mexican American men and women's opinions of what would be the content and structure of informative and effective decision aids for colorectal cancer (CRC) that would optimize decision making of preventative measures and screening procedures.

Methods: A qualitative study consisting of 5 focus groups (3 of women and 2 of men) was conducted. The criteria for eligibility consisted of being 50 years or older, El Paso county resident, Hispanic, and fluent in English. All focus groups were held at the University of Texas at El Paso and lasted on average 1 hour. Upon arrival, participants were asked to sign a consent form stating their voluntarily participation and completed a demographic questionnaire. After each focus group session, participants were debriefed and received a $20 gift certificate. A trained moderator led each focus group session, using as a guide a set of questions previously established by the team of researchers. All focus group sessions were recorded with the consent of all participants and kept confidential. All recordings were transcribed by two different assistants and evaluated to find major themes and sub-themes. The transcriptions and themes were then entered into the program ATLAS.ti 5.2. A coding framework was developed based on the participants' comments. Broad topics and salient points were identified to evaluate overlapping themes.

Results: A total of 23 individuals participated in the focus groups. The majority of the participants (73.9%) were married women, almost half were employed (43.5%), and more than a third had some college training (40%). There were 6 major themes found across focus group sessions: current knowledge, barriers, external controls, desired information, decision aid tools, and elements of persuasion. We found that not only participants lacked education about CRC and screenings but across focus groups, participants had some misleading information such as Hispanics are not at risk for CRC, men are more prone to CRC, CRC isnot hereditary, and CRC cannot be diagnosed on its early stages. Furthermore, participants shared, based on their past experience, various means to communicate and educate the community in an effective manner.

Conclusion: In spite of the large body of information on CRC and screening, there were many misconceptions and lack of meaningful knowledge across focus groups. However, faith, fate, and family play a large role as decision aid tools in getting screened. Perhaps, future studies might focus their efforts on one or all three components. Furthermore, networks of family and friends seem effective dissemination tools to advocate CRC screening. These networks would be efficient in dissipating misinformation and reducing fear of procedures with the accurate information. Furthermore, according to their suggestions, several decision aid tools should be incorporated and presented together as one large and more comprehensive decision aid tool to help individuals make informed decisions.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B10.

Abstract PR-10: The association of neighborhood socioeconomic context and mortality in a large national cohort in the United States: The NIHA-ARP Diet and Health Study

Doubeni, C., Laiyemo, A. O., Lian, M., Park, Y., Schootman, M., Schatzkin, A. — Thu, 07 Jan 2010 13:54:29 PST

Background: Although several studies have reported that persons from lower socioeconomic groups have poorer health outcomes, few prospective studies have examined whether neighborhood socioeconomic context is associated with mortality. In this study, we prospectively evaluated whether persons residing in socioeconomically deprived neighborhoods have higher mortality risk compared to more resourced neighborhoods among a large geographically dispersed cohort.

Methods: Between 1995 and 1996, the NIH-AARP Diet and Health Study recruited an ethnically diverse prospective cohort of 566,402 persons, 50–71 years of age, from six U.S. states and two metropolitan areas. Detailed data were collected on diet, lifestyle, and medical history through questionnaires. Neighborhood socioeconomic information was obtained through linkage to the 2000 U.S. Census data at the tract level. We excluded 705 subjects with incomplete information for geocoding and computed an empirically derived index of neighborhood socioeconomic deprivation using principal component analyses. Mortality was ascertained through December 31, 2006. Two-level continuous-time survival models were used to derive hazard ratios of time to death from any cause stratified by gender.

Results: Of the 565,697 eligible subjects at baseline, the mean age was 62 years, 60% were male, 91% were non-Hispanic whites, 4% non-Hispanic blacks and 9% reported a history of cancer. A higher percentage of those in the most deprived neighborhoods reported poorer general health, higher average BMI, and lower Mediterranean diet scores. In multilevel Cox models analyses controlling for dietary and lifestyle factors, the risk of death increased with increasing levels of deprivation in the neighborhood of residence. Compared to the least deprived neighborhood, those residing in areas in the highest quintile of deprivation had a higher risk for death (men: hazard ratio [HR]: 1.22, 95% confidence interval [CI]: 1.18–1.25); women: HR: 1.23, 95% CI: 1.17–1.29).

Conclusion: Our study suggests that living in socioeconomically deprived neighborhoods is associated with a higher risk for death independent of lifestyle and dietary risk factors.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):PR-10.

Abstract A11: Development of minimally invasive techniques for monitoring genome health: A preventative health approach to reducing disease

O'Callaghan, N., Bull, C., Fenech, M. — Thu, 07 Jan 2010 13:54:01 PST

It is becoming increasingly evident that risk for developmental and degenerative disease, including cancers, increases with more DNA damage. Importantly, DNA damage is influenced (and can be modified) by nutritional status. Optimal concentrations of nutrients for reduction of genome damage are also dependent on many factors (genetic background, age, nutrient uptake) that vary from individual to individual.

In the genomic health era of personalised nutrition for disease prevention, there is a need to develop minimally invasive methodologies to measure alterations in disease risk biomarkers in an effort to identify at risk individuals early in disease progression. Using qPCR techniques developed by us, we aimed to evaluate the use of buccal cells and saliva as a minimally-invasive approach to measure markers of genome health in a cross-sectional study.

Buccal cells, saliva and blood samples were collected from 91 volunteers. This cohort comprised 18M and 25F in the young group (aged 18–31 years), and 25M and 23F in the older group (65–75yrs). Telomere length was determined in lymphocytes, buccal cells and saliva (by qPCR). Telomere length was negatively correlated with age; the strength of this correlation varied between gender and tissue type.

We report that buccal cells and saliva can be used to measure DNA damage. Further research is required to evaluate the effectiveness of buccal cells and/or saliva as a minimally-invasive biomarker of oxidative DNA damage, genome health and disease risk status.

The development of dietary patterns, functional foods and supplements that are designed to improve genome-health maintenance in an individual with increased disease risk may lead to a preventative health strategy based on the diagnosis and individualised nutritional prevention of genome damage.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A11.

Abstract B11: Racial differences in prostate cancer caregivers' social support and coping

Vines, A. I., Demissie, Z. — Thu, 07 Jan 2010 13:54:13 PST

Objective: Over 40 million Americans provide informal caregiving to adults, which can negatively impact their personal life and their physical and mental health. The purpose of this study was to describe social support and coping strategies among prostate cancer family caregivers and to assess for racial/ethnic differences.

Methods: Secondary data analysis of baseline data from the Managing Uncertainty in Stage B Prostate Cancer Study was conducted. This longitudinal randomized experimental intervention study enrolled Caucasian and African-American men with localized prostate cancer and their primary family caregivers residing in North Carolina from 1993–1998. 120 Caucasian and 49 African-American female family caregivers of prostate cancer patients were included in the analysis. We compared means of social support amount and satisfaction and utilization of coping strategies by race/ethnicity group.

Results: Racial/ethnic differences exist in the amount of social support received and some coping methods. However, there was no variation in satisfaction with social support by race or ethnicity.

Conclusions: Results suggest that though Caucasian and African-American female family caregivers differ in the amount of social support received, the level of satisfaction with the support tends to be consistent across race/ethnic groups. Racial/ethnic differences in coping methods need to be elucidated since the way of coping may reflect important sociocultural factors.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B11.

Abstract A12: Increased urinary 8-hydroxy-2'-deoxyguanosine excretion in long-distance bus drivers in Taiwan

Han, Y.-Y., Donovan, M., Sung, F.-C. — Thu, 07 Jan 2010 13:54:01 PST

Objective: Professional bus drivers are exposed to environments containing air pollution and reactive oxygen species (ROS) that can induce cellular oxidative stress and DNA damage. This study investigated environmental factors associated with oxidative DNA damage in a cohort of long distance bus drivers.

Methods: In a comparison study, urinary 8-hydroxydeoxyguanosine (8-OHdG), a biomarker of DNA oxidative damage, was examined in 120 male long distance bus drivers and 58 male office workers in Taiwan. Multivariate logistic regression was used to analyze association between urinary 8-OHdG levels and environmental factors.

Results: Bus drivers had higher urinary 8-OHdG levels (adjusted odds ratio (aOR) = 9.4, 95% confidence interval (CI) = 3.5–28.2) compared with office workers. Increased urinary 8-OHdG level was significantly related to cigarette smoking (aOR = 18.0, 95% CI = 7.1–52.1), consumption of energy drinks (aOR = 5.0, 95% CI = 2.1–12.6), and regular exercise (aOR = 3.8, 95% CI = 1.5–10.2). A strong exposure-response relationship was found between urinary 8-OHdG and urinary cotinine (p < 0.0001). Among nonsmokers, bus drivers (aOR = 3.9, 95% CI = 1.0–17.7) had higher urinary 8-OHdG than office workers. Among both bus drivers and office workers, those who drank energy drinks (aOR = 3.7, 95% CI = 1.2–12.2) had higher 8-OHdG levels than those who did not drink energy drinks.

Conclusion: Adjusted for smoking, levels of 8-OHdG were increased in long-distance bus drivers exposed to traffic exhaust and ingested energy drinks. Future studies should explore what aspects of energy drinks may contribute to increased urinary 8-OHdG.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A12.

Abstract B12: Racial disparities in breast cancer treatment delay and type in three North Carolina counties

Vines, A. I., Nie, Y., Amos, K. — Thu, 07 Jan 2010 13:54:13 PST

Objective: The purpose of this study was to explore racial disparities in delays in treatment and type of treatment received among breast cancer patients in three North Carolina counties represented in the Carolina Community Network to Reduce Cancer Health Disparities (CCN). The CCN is a regional community-based cancer network that aims to reduce prostate, breast and colorectal cancer disparities among adult African Americans in North Carolina.

Methods: North Carolina Central Cancer Registry data on black and white women diagnosed with breast cancer in Orange, Edgecombe, and Nash counties between 2000 and 2005 (n=1205) were used to obtained information on treatment and tumor status. Using standard guidelines for breast cancer care, delay in first course of treatment, type of treatment received, and tumor receptor status were assessed.

Results: Although within the recommended guidelines, treatment delay was longer for black breast cancer patients in comparison to white patients, regardless of stage at diagnosis. Treatment delay was highest for black patients in Edgecombe, a county with the highest proportion of blacks overall. Majority of stage I and II breast cancer patients received surgery and tended to elect for breast conservation surgery over mastectomy. Estrogen and Progesterone receptor negative breast cancers were more common in blacks than whites across the three counties, especially in Edgecombe County.

Conclusions: Our findings suggest treatment standards are not equivalently met among black and white women. Findings warrant further research into the identified treatment delays and tumor type differences to improve survival for black women, especially those in Edgecombe County. These preliminary results suggest that patients in Edgecombe County may have a higher prevalence of the hormone receptor negative phenotype of breast cancer. This more aggressive type of breast cancer may be attributing to the higher mortality rates in comparison to the other two counties.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B12.

Abstract A13: Overexpression of adipokine receptors and dysregulation of AMPK signaling in normal and hyperplastic endometrium from obese women

Thu, 07 Jan 2010 13:54:01 PST

Background: Excess adipose tissue in the obese woman produces inflammatory cytokines, called adipokines, that are thought to regulate proliferation in peripheral tissues such as the endometrium to promote the development of cancer. Epidemiological studies indicate that the adipokines IL-6, leptin, TNF and adiponectin are dysregulated in the obese woman and in women with endometrial cancer (EC). Activation of the IGF-IR/PI3K/mTOR pathway is an important contributor to the development of endometrial complex atypical hyperplasia (CAH), the precursor to endometrioid-type endometrial cancer. Adipokines act through their receptors to activate pathways that exhibit signal transduction crosstalk with the IGF-IR/PI3K/mTOR pathway that is thought to either promote activation (IL-6, leptin) or inhibit this pathway (TNF, adiponectin). The goal of these studies was to assess the corresponding adipokine receptors (IL-6R, IL6-Rβ, Ob-Rb, AdipoR1, AdipoR2, TNFR1 and TNFR2) expression and activation of AMPK and IGF-IR/PI3K/mTOR signaling pathways in normal endometrium from lean and obese women and in endometrial hyperplasia from obese women.

Methods: We quantitated adipokine receptor transcript levels of the receptors by qRT-PCR in timed endometrial biopsies obtained from lean women (BMI < 25 kg/m²) and obese women (BMI > 30 kg/m²) that were histologically confirmed to have normal proliferative phase endometrium. These biopsies were compared to biopsies from obese women with endometrial CAH. We assessed functional activation of AMPK and mTOR pathways by immunohistochemistry.

Results: There was a significant stepwise increase in the expression of AdipoR1, TNFR1 and TNFR2 in normal lean endometrium, normal obese endometrium and obese endometrial CAH. In addition, IL-6Rβ transcripts were significantly increased in obese endometrial CAH as compared to both lean and obese normal endometrium. Phosphorylation of AMPK was increased in obese normal endometrium compared to lean normal endometrium. Surprisingly, in endometrial CAH mTOR signaling was activated and activation of AMPK was lost compared to lean and obese normal endometrium.

Conclusions: The stepwise increase in the expression of AdipoR1, TNFR1 and TNFR2 in the obese endometrium and endometrial CAH as compared to normal lean endometrium suggests that dysregulation of adipokine receptor expression is an early event and may be predictive of women at risk of developing endometrial CAH and EC. The overexpression of AdipoR1 in obese endometrium may contribute to activation of AMPK. The overexpression of AdipoR1 and activation of AMPK in obese endometrium may be a compensatory mechanism to dampen growth factor signaling through the IGF-IR/PI3K/mTOR pathway. In endometrial CAH there is upregulation of IL-6Rβ which may contribute to activation of mTOR by activating PI3K upstream. Activation of mTOR and loss of AMPK activation may contribute to the abnormal proliferation seen in endometrial CAH. These studies suggest that overexpression of adipokine receptor expression may be an important contributor to the risk of endometrial hyperplasia and cancer in obese women.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A13.

Abstract B13: Arizona cancer research network analysis: Discovery to delivery

Leischow, S., Provan, K., Keagy, J., Nodora, J. — Thu, 07 Jan 2010 13:54:14 PST

Background: Networks are frequently viewed as important for moving innovation beyond the boundaries of individual organizations, especially for enhancing translational research. This study used social network analysis to discover the extent and nature of involvement in collaborative relationships among the key organizations participating in cancer research activities in Arizona.

Methods: Data were collected in 2007 from 18 of 21 organizations involved in research in the Arizona Cancer Coalition, including academic institutions, private research institutes, and organizations dedicated to healthcare delivery, public health and support/advocacy. Key informants in each organization reported their collaborative relationships with every other organization in the Coalition for each of three types of cancer research activities, discovery, development, and delivery (3D). Data were analyzed using network analytic software (UCInet). Network measures included two global ‘whole network’ measures (network centralization and density) and one organizational level measure (degree centrality).

Results: The results of the network analysis showed the most highly connected, or dense, network ties were found when cancer research focused on delivery, closely followed by discovery. Organizational centrality in the development network is highly and positively correlated with both centrality in the discovery (r=.71, p<.001) and the delivery networks (r=.77, p<.001). In contrast, the relationship between centrality in the discovery and delivery network is quite weak (r=.33, not significant).These findings are consistent with the fact that discovery and delivery are at opposite ends of the research continuum, and thus, the central actors in each network are less likely to overlap. In addition, the importance of cancer research to an organization's mission is strong and positive, but only for the discovery (r=.61, p≤.01) and development (r=.51, p≤.05) networks

Conclusions: The research demonstrated how network analysis can be used to understand the extent to which organizations involved in cancer research are able to collaborate both within and across the 3D continuum. Findings suggested substantial differences in network involvement, depending on the type of research being conducted, while also demonstrating the key role played by a comprehensive cancer center in connecting organizations that might be involved in very different aspects of the research process.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B13.

Abstract A14: Chromosomal aberrations predict malignant progression and treatment response of Barrett's-related esophageal neoplasia: A genome-wide high-density SNP array analysis

Gu, J., Ajani, J. A., Hawk, E., Ye, Y., Wang, K. K., Wu, X. — Thu, 07 Jan 2010 13:54:01 PST

Chromosomal aberrations occur frequently during malignant progression from Barrett's esophagus (BE) to esophageal adenocarcinoma (EAC). In this study, we applied Illumina's 317K high-density SNP arrays to profile chromosomal aberrations at each of the four sequential stages of progression - Barrett's metaplasia (BM), low-grade dysplasia (LGD), high-grade dysplasia (HGD), and EAC. We observed significant trends of increasing LOH/deletion associated with the degree of progression. The average numbers of chromosome arms with LOH/deletion per sample were 0.30, 3.21, 7.70, and 11.90 for BM, LGD, HGD, and EAC, respectively (p-for trend=4.82x10^–7). The mean percentages of SNPs with LOH/deletion events were 0.1%, 1.8%, 6.6%, and 17.2% for BM, LGD, HGD, and EAC, respectively (p-for trend=2.64x10^–6). In BM, there were scattered chromosome deletions at 3p14.2 (10%), 16q23.1 (5%), and 9p21 (5%), which became predominant aberrations in LGD. More importantly, the 3p14.2 (68.4%) and 16q23.1 (50%) LOH/deletion in LGD was exclusively limited to narrow regions within the FHIT (3p14.2) and WWOX (16q23.1) genes, the two most frequent common fragile sites in the human genome. In contrast, the 9p21 deletion (68.4%) occurred in larger regions (encompassing p16 gene), often involving the whole 9p arm. A significant increase in LOH/deletion of other chromosomes was seen in HGD and there was widespread LOH/deletion across the whole genome in EAC. 17p (47.6%) LOH was the most frequent event in EAC, which mostly spanned the entire 17p arm with only one focal site of LOH at 17p13.1. There were many recurrent small regions of LOH/deletion that disrupted a single gene, most of which are common fragile sites in the human genome. RUNX1 is a potential tumor suppressor gene in EAC. Amplifications were rarer than LOH/deletions. The average numbers of chromosome arms with amplification per sample were 0.30, 0.42, 1.90, and 8.50 for BM, LGD, HGD, and EAC, respectively (p-for trend=1.35x10^–9). The mean percentages of SNPs with amplification were 0.5%, 0.4%, 1.5%, and 8.0% for BM, LGD, HGD, and EAC, respectively (p-for trend=1.26x10^–8). The most frequent chromosome amplifications in EAC were 8q24.21 (36.6%, MYC), 8p23.1 (31.7%, CTSB), 7q21 (30.8%, CDK6), 20q13.2 (28.6%, ZNF217), and 7p11.2 (25.6%, EGFR). We then analyzed the associations of chromosomal aberrations with clinical features and pathological response in EAC patients treated with neoadjuvant chemoradiation. The number and size of LOH/deletion were significantly associated with pathological response. Non-responders had a greater number (16.4 vs. 8.5, p=0.060) and larger size (662.2 Mb vs. 290.7 Mb, p=0.034) of LOH/deletions, and higher percentage of aberrant SNPs (25.2% vs. 11.2%, p=0.030) than responders. This study provides a genome-wide catalogue of chromosome aberrations occurring during the malignant progression from BE to EAC with the highest resolution to date. Our data support genetic instability and p16 loss as drivers of early neoplastic progression from metaplasia to dysplasia, and p53 aberrations as late events critical for progression to adenocarcinoma. Chromosomal aberrations can predict malignant progression and treatment response in EAC, which may have important clinical implications for cancer prevention and personalized treatment of EAC.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A14.

Abstract B14: Factors associated with adolescent HPV vaccine uptake in safety-net clinics

Tiro, J. A., Bruce, C., Bishop, W. P., Goodell, K., Skinner, C. S. — Thu, 07 Jan 2010 13:54:14 PST

Background: Cervical cancer disproportionately affects minority and low socioeconomic status (SES) populations and could be nearly eliminated if prevention and screening were universally available and used. Uptake of the human papillomavirus (HPV) vaccine could reduce disparites. Clinic, provider, and patient factors determining vaccine use in the US are not well understood. Most studies of correlates have relied on patient self-report.

Aim: Use behavioral model of health services utilization to examine patient, provider, and clinic characteristics associated with HPV vaccine use among females ages 11–18 receiving care in safety-net clinics.

Methods: Retrospective medical record review of a random sample of 353 female patients ages 11–18 who had an index visit between March 2007 and February 2008 at one of two safety net clinics which provide primary care to underserved populations. Dependent variables abstracted included: physician recommendation; HPV vaccine acceptance; number of doses delivered (0–3); and timeliness (e.g., on-schedule delivery of doses). Independent variables included patient sociodemographics, health care access, vaccine and sexual behavior, and clinic documentation. Chi-square tests (p<0.05) identified significant factors.

Results: The sample was diverse (N = 353; 38.5%African American, 53.5% Hispanic, 52.7% age <15, 93.2% publicly insured, 39.1% with a clinic visit in the past year, 34.6% sexually active). Only 140 out of 353 eligible female patients (39.7%) received a recommendation from a health care provider. Patient factors associated with provider recommendation were younger age (<15), being Caucasian, having some type of insurance, visiting the clinic in the past year, receipt of other recommended adolescent vaccines (TDAP and MCV4), receipt of flu shot in past year, and not being sexually active. Clinic documentation of Vaccine for Childrens program eligibility, vaccine record, and completion of health maintenance form in past year was also associated with provider recommendation. Of those who received a recommendation, only 24.3% refused the vaccine, most initiated the series (59.3% received 1–2 doses), and 16.4% completed all three doses. Only 1 patient completed the series according to CDC guidelines for timely delivery. The only factor associated with vaccine refusal among those who received a recommendation was lack of receipt of other adolescent vaccines.

Conclusions: Even in a safety-net clinic population where female adolescents have access to care, HPV vaccine delivery is suboptimal. Delivery breaks down at two points: physician recommendation and dose completion. Our data show that most patients do not receive a physician recommendation. Of those who get a recommendation, most patients initiate the series, but do not complete all three doses. Chart reminders that improve provider recommendation and patient-directed reminders to address delivery of second and third doses are urgently needed.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B14.

Abstract B15: Measuring medical mistrust at Dia de la Mujer Latina health fiestas

Gines, V. M., Pena, G. — Thu, 07 Jan 2010 13:54:14 PST

Mistrust of research and the medical system is a frequent barrier to participation in clinical trials. However, there is a paucity of data on how medical mistrust serves as a barrier to participation in clinical research among Latinas from various Latin American ethnic groups. Culturally, Latina women are the key decision makers when it comes to healthcare. Therefore, this study focused on Latinas who attended three Dia de la Mujer Latina (DML) health fiestas.

Methods: Promotoras de Salud (community health workers) were trained to present a bilingual Medical Abuse and Medical Mistrust Awareness Survey (MAMMAS©), culturally translated, to Latinas from 18 years of age and older at 3 DML Health Fiestas events (Puerto Rico, Houston,Texas and Miami, Florida). MAMMAS© is innovative because it breaks down their perception of the medical institutions as well as their knowledge of clinical research, the HPV vaccine and the well-documented medical abuse historical cases. Questions captured demographics, insurance coverage, assimilation, acculturation, knowledge of preventive screenings for breast and cervical cancer, understanding and perception of clinical trials, awareness of historical medical abuse, mistrust of medical providers, their insights about barriers to obtaining these cancer screenings; and if the barrier of mistrust would hinder them from participating in a clinical research or clinical trial.

Conclusions: The results of the MAMMAS survey will emphasize the need for more research on this topic. There were a total of 357 participants who completed the survey, however, there were 527 who began the process but did not complete due to their confusion with the response scale.

201 Survey respondents were conscious of the importance of cancer screening, but expressed fear as a major barrier.

294 Survey respondents believed that mistrust plays a key role in their participation into clinical trials.

253 Survey respondents felt that patients may have been deceived or misled by healthcare organizations

204 Survey respondents stated that mistakes are usually covered up by healthcare organizations.

227 Survey respondents believed that healthcare organization have experimented on patients w/o their knowledge.

269 Survey respondents were aware of some form of medical abuse that occurred.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B15.

Abstract A16: DNA microarray analysis of the UPII-SV40Tag model for invasive bladder TCC: Identification of markers for bladder premalignancy

Thu, 07 Jan 2010 13:54:01 PST

Transitional cell carcinoma of the bladder (TCC) ranks 4th in incidence of all cancers in the developed world, yet the mechanisms of its origin and progression remain poorly understood. There are a few commercially available urine-based tests for screening and surveillance for bladder cancer, but none of these can detect premalignancy. We have combined a transgenic mouse model for invasive bladder cancer (UPII-SV40Tag mice) with DNA microarray technology, in order to determine molecular mechanisms involved in early TCC development and to identify new biomarkers for detection, diagnosis and prognosis of TCC. We have identified genes that are differentially expressed between the bladders of UPII-SV40Tag mice and their age-matched wild type (WT) littermates at 3, 6, 20 and 30 weeks of age. These are ages which correspond to premalignant, carcinoma in-situ, and early and later stage papillary TCC, respectively. There were approximately 1,900 unique genes differentially expressed (>= 3-fold difference at one or more time points) between WT and UPII-SV40Tag urothelium during the time course of tumor development. Among these, there were a high proportion of cell cycle regulatory genes and proliferation signaling genes that are more strongly expressed in the UPII-SV40Tag bladder urothelium. We have tested several of the genes upregulated in UPII-SV40Tag urothelium, including autocrine motility factor (AMFR), hyaluronan-mediated motility receptor (Hmmr), proliferating cell nuclear antigen (PCNA), Rac GTPase activating protein 1 (RacGAP 1) and others as biomarkers for premalignancy, in urine samples from a recently completed Phase II, randomized, placebo controlled chemoprevention trial (N01 CN85186, PI: A. Sabichi) that was designed to test whether celecoxib can prevent recurrence in patients successfully treated by TUR for non-muscle invasive bladder cancer.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A16.

Abstract B16: The influence of cultural beliefs on breast cancer risk factor knowledge of women in Kumasi, Ghana

Thu, 07 Jan 2010 13:54:14 PST

Background and Significance: Breast cancer is the second leading cause of cancer death among women in Ghana, West Africa. Previous studies of breast cancer among women in Ghana indicate that 70 – 80% of women who seek treatment for breast problems are diagnosed with Stage III and IV breast cancer tumors. The objectives of this study were to determine 1) the knowledge of general cancer risk factors, and 2) the knowledge of general cancer signs and symptoms among women in Kumasi, Ghana; and 3) to identify cultural factors that influence their beliefs about breast cancer risk factors.

Methods: Semi-structured interviews were conducted using a questionnaire with 53 qualitative and quantitative items. Female residents (n=220) of Kumasi, Ghana where selected to participate in the study. A purposive sampling plan was designed to ensure that women with breast or cervical cancer (n = 49) where included in the study. Interviews where conducted in public areas, the Peace and Love Hospital, and the Komfo Anokye Teaching Hospital. Comparative and descriptive statistics were used analyze the data.

Results: Findings indicated that the respondents' cancer risk factor knowledge was relatively low (mean score 2.91; range 0 – 5) and the difference in the cancer risk factor knowledge scores of women with various levels of education was not statistically significantly different. The overall knowledge of cancer signs and symptoms was also low (mean score 2.19; range 0 –6). In addition, cultural beliefs had an influence on women's beliefs about the risk factors for breast cancer e.g. 10.9% of respondents indicated that money in the bra causes breast cancer.

Conclusions: There is a wide-spread lack of accurate knowledge of general cancer risk factors and cancer signs and symptoms. There is a need for a mass breast cancer education intervention. Inaccurate cultural beliefs must be addressed to correct misconceptions about the causes of breast cancer.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B16.

Abstract A17: Using high-throughput imaging cytometry to unmask the true nature of oral lesions in a high-risk community

Poh, C. F.Y., Guillaud, M., Zhang, L., MacAulay, C., Rosin, M. — Thu, 07 Jan 2010 13:54:01 PST

Vancouver's Downtown Eastside is a high-risk community for oral cancer. Previous study has shown its prevalence of tobacco and alcohol consumption and high incidence of oral cancer (one cancer identified in 150 residents screened). Additionally, oral infection and inflammation are commonly seen in this community. In British Columbia, we are evaluating several technologies and their interactions for the screening and early detection. Direct fluorescence visualization (FV) has shown its high sensitivity for the detection of oral cancer or precancer, but can also highlight other oral conditions which are commonly seen within community setting. We start to look at the utility of imaging cytometry as an adjunct tool in oral cancer screening. There is an urgent need to develop an effective strategy for oral cancer screening in such a high risk community.

Objectives: 1) To using imaging cytometry to measure the altered nuclear phenotype (cNPS) and 2) To see if cNPS can increase the accuracy of using FV only for oral screening.

Methods: From 2004/11–2009/2, we have collected 355 exfoliative cell samples using a small curved interdental tooth brush from this high-risk community. Samples were spun down onto slides, the DNA quantitatively labeled and automatically scanned by the cyto-savant®. For each object (nucleus/debris) imaged ~110 features were calculated and used by a cell recognition decision tree to differentiate cells from debris.

Results: Among 355 brushings, 4 from cancerous sites, 90 from non cancerous common oral lesions (60, trauma; 28, inflammation; 12, infection), and from tongue with no lesion under clinical white light and FV examinations. Using previously trained algorithm with 84% sensitivity and 97% specificity to examine these samples, there was no difference between gender, age groups, smoking habit, and immune status (presence of HIV infection). This algorithm can correctly identified 3 out of 4 high-grade lesions and 89% normal cases. For those non-cancerous common oral lesions, using FV followed with the examination of cNPS at the FV loss area can drastically increase the accuracy from 10% to 83% (trauma, 13% to 90%; inflammation, 6% to 78%; infection 0% to 75% respectively).

Conclusion: The pilot results indicate support the potential usage of the combination of direct FV and imaging cytometry in oral cancer screening in a high-risk community.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A17.

Abstract B17: Impact of behavior modification for tobacco usage in patients with a diagnosis of high-risk oral lesion

Tam, D. M., Currie, B., Zhang, L., Rosin, M. P., Poh, C. F.Y. — Thu, 07 Jan 2010 13:54:14 PST

Background: With tobacco and alcohol risk behaviors contributing to about three-quarters of cases, oral cancer is recognized as a preventable disease. Continuous smoking after treatment for high-risk oral lesions (HRLs) is associated with recurrence risk. However, there is little known about the impact of smoking behavioral changes in patients diagnosed with HRLs or their barriers for tobacco cessation.

Objectives: 1) To collect pilot data regarding tobacco-related behavioral changes prior to and after the diagnosis of an HRL, and 2) To identify possible facilitators and barriers in tobacco cessation.

Methods: A survey-type questionnaire is being developed for collecting data on smoking behaviors and cessation barriers. To avoid recall bias, patients with ever-smoking histories within 5 years of the diagnosis of an HRL are invited to participate in the study. A pilot cohort (N=25) has been interviewed to develop a refined questionnaire for a larger scale study.

Results: Initial results show that all patients interviewed have a general understanding of the associations between tobacco consumption and its consequences on health. Of 25 patients recruited, there were 16 (64%) males and the average age is 55 ± 6.3 years. Ten (40%) have successfully quit after the diagnosis of an HRL and 6 (24%) expressed the intention to quit; while 6 (24%) have not made a decision regarding tobacco cessation and surprisingly, 3 (12%) have no intention of ceasing their tobacco habits even with a diagnosis of an HRL. All but 2 patients have experienced difficulty in tobacco cessation and 16 (64%) of them experienced smoking recurrence after their attempts to quit. The identified cessation barriers are mainly stress (‘smoking is a way to relax’, 64%) and smoking enjoyment (56%). The HRL diagnosis is the strongest message for the patients who quit successfully.

Conclusion: Incorporation of an open-ended interview questionnaire allows for better understanding of smoking behaviors and complex cessation barriers in patients with HRLs. The barriers to tobacco cessation appear to be more psychosocial in nature, i.e., stress and smoking enjoyment. There is a need to develop effective intervention strategies targeting these individuals to improve tobacco cessation success, and consequently, reduce the risk of HRL recurrence. (Supported by research grants from the Canadian Institutes of Health Research (CIHR), Michael Smith Foundation for Health Research, and BC Cancer Foundation. DMT is supported by the Frederick Banting and Charles Best Canada Graduate Scholarships administered by CIHR.)

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B17.

Abstract A18: Spatial dynamics of cellular proliferation in preneoplastic lesions: Comparison between bronchial, oral, and cervical epithelium

Thu, 07 Jan 2010 13:54:02 PST

Introduction: Uncontrolled proliferation is a hallmark of cancer and a biologically plausible risk biomarker for preneoplastic epithelium. The expression Ki-67 has been widely used as a marker of cellular proliferation even though it does not specifically elucidate the complexity of clonal growth that eventually drives a normal homeostatic epithelium towards carcinoma in situ. Our objective is to quantify the spatial dynamics of cellular proliferation in pre-neoplastic lesions of three different tissue types; bronchial, oral and cervical epithelium.

Materials and Methods: Five hundred sixty-two bronchial lesions, seventy nine oral mucosa lesions, and two hundred sixty five cervical lesions were reviewed by at least two pathologists. Expression of Ki-67 was studied by Mib-1 immunohistochemistry. Using an in-house imaging system, a mapping of the regions of interest were performed; nuclei positions were registered; Mib-1 positive cells were manually marked, the basal membrane and the external surface delineated. Using graph-theory tools, the spatial arrangements of all nuclei, in addition to the spatial distribution of Mib-1 positive nuclei were measured. The percentage of Mib-1 positive nuclei within each layer - from the basal layer to the superficial layer - was a study focus.

Results: On average, proliferation increased with pathology grade. Nevertheless, the amplitude and the patterns of cellular proliferation within the different layers differ among the different tissue types. The propotions of Mib-1 positive cells in the bronchial, oral, and cervical normal epithelium were respectively: 19.8%, 6.3%, and 6.1% in the basal layer; 18.7%, 28.5% and 33.2 in the layer 1; 8.0%, 18.7% and 31.1% in the layer 2. For specimens classified as mild dysplasia, the proportion of Mib-1 positive cells in bronchial, oral and cervical dysplastic epithelium were respectively: 42.0%, 19.3%, and 21.5% in the basal layer; 63,2%, 19.3%, and 43.5% in layer 1; 61.8%, 9.9% and 50.0% in layer 2. Furthermore, we observed a high variability of the proliferation patterns (along the different layers) in each tissue within each pathology grade. The significance of these findings and their correlation with other biomarkers (quantitative nuclear phenotype, p16 staining, LOH, etc.) and with clinical parameters (age, sex, HPV status, cancer progression, etc..) will be shown.

Conclusions: Quantitative analysis of spatial patterns and arrangement of proliferating cells squamous dysplastic lesions provide additional insights in the dynamic nature of these early neoplastic changes.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A18.

Abstract A19: S100A7, a prognosticator and early predictive marker for head and neck/oral squamous cell carcinoma

Thu, 07 Jan 2010 13:54:02 PST

Recently using multidimensional LC-MS/MS with iTRAQ-tagging, we identified a panel of potential Head and Neck/Oral Squamous cell carcinoma (HNOSCC) biomarkers. S100A7 was one of the promising candidate biomarkers in this panel. S100A7 is 11.4 kDa calcium-binding protein of S100 protein family, found to be highly expressed in pre-invasive ductal carcinoma in situ of the breast. Here, we firstly report its potential as a prognostic biomarker for HNOSCC. The present study also further explores the clinical significance of S100A7 in identification of oral leukoplakic lesions in early stages.

Ninety-nine HNOSCCs, 100 leukoplakias and 50 non-malignant archived tissues were retrieved from the research tissue bank to determine the expression of psoriasin using immunohistochemistry. The immunohistochemical data were subjected to statistical analyses using the SPSS 13.0 software (Chicago). Sensitivity and specificity were calculated and quantified using receiver operating characteristic (ROC) analysis. The expression of S100A7 in oral lesions was further validated by immunoblotting and RT-PCR analyses in the same tissue samples as used for immunohistochemical analysis.

S100A7 expression was found to be significantly increased from normal mucosa to leukoplakia with or without dysplasia to HNOSCC (p_trend<0.001). Receiver Operating Characteristic (ROC) analysis was used to determine the potential of S100A7 as a biomarker for diagnosis of leukoplakia and OSCC. The area-under-the-curve (AUC) value was 0.732 and 0.843 for leukoplakia and OSCC respectively. S100A7 overexpression was significantly associated with dedifferentiation of tumors also. Cytoplasmic S100A7 was significantly associated with tumor size (p=0.015) and stage (p=0.023) of HNOSCC patients. In univariate analysis, nuclear localization of S100A7 was found to be associated poor survival (p < 0.014), while multivariate analysis revealed nuclear S100A7 as independent indicator of disease free survival (hazard ratio, 2.7; 95% confidence interval, 1.4–5.3; p < 0.004).

This is the first large-scale study that suggests overexpression of S100A7 to be an early event and a poor prognostic factor in HNOSCC progression. On the basis of our current findings, S100A7 may serve as a potential biomarker in diagnosis and prognosis of HNOSCCs.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A19.

Abstract B19: Complementary and alternative medicine use among postmenopausal breast cancer survivors: The Black Women's Health Study

Bright-Gbebry, M. J. — Thu, 07 Jan 2010 13:54:14 PST

Background: Complementary and alternative medicine (CAM) is widely used among women in the United States. However, there is limited knowledge about the use of CAM modalities in minority women despite the relationship of CAM use to cultural and health beliefs. We defined CAM use as the intake of natural herbs, vitamins and mineral products at least three days per week. The primary objectives of this study were to determine the prevalence of CAM usage in African American breast cancer survivors, and to compare the characteristics of users and nonusers.

Design: A cross-sectional study of breast cancer survivors who completed the 1999 Black Women's Health Study questionnaire and reported having been diagnosed with breast cancer by 1999. A total of 436 women were included in the analysis.

Results: Overall, 69% of breast cancer survivors compared to 59% noncases used one or more CAM products, including herbs, vitamins and minerals. Among breast cancer survivors the mean age for CAM users was 53.1 years compared to 51.3 years in nonusers. Among breast cancer survivor CAM users, garlic was the most widely used product (20.9%), followed by echinacea (12.6%) and gingko (11.7%). More CAM users chose a multivitamins supplement (53.9%) over a folic acid supplement alone (4.1%). Multivariate analysis determined that age (OR per year of age =1.05; 95% CI:1.02–1.08), and marital status (OR for single relative to married or living as married =0.33; 95% CI:0.15–0.70) were the factors significantly associated with CAM use among breast cancer survivors.

Conclusions: CAM use is common in postmenopausal African American breast cancer survivors. Our results are consistent with prevalence rates of 60–70% reported in studies of CAM use by women with breast cancer following diagnosis.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B19.

Abstract A20: Random periareolar fine-needle aspiration is highly reproducible in a CALGB multi-institutional cross-sectional study

Thu, 07 Jan 2010 13:54:02 PST

Background: Biomarkers that vary with risk and response to prevention interventions are referred to as "surrogate endpoint biomarkers". As outlined by Fabian et al., surrogate endpoint biomarkers should be 1) biologically and statistically significantly associated with cancer development, 2) present in a reasonable proportion of at-risk individuals, 3) obtainable by minimally invasive procedures, and 4) reversible with prevention interventions that have been validated to decrease cancer incidence. Many modalities have been suggested as potential surrogate endpoint biomarkers for breast cancer, including mammographic density, serum biomarkers, and breast tissue biomarkers. Currently, there is no consensus as to the optimal surrogate endpoint biomarker.

Random Periareolar Fine Needle Aspiration (RPFNA) is a research technique developed to assess short-term breast cancer risk in women at increased risk for breast cancer. While there is increasing acceptance of RPFNA, neither the reproducibility nor the inter-institutional compatibility of RPFNA has been established. To address these key limitations, the Cancer and Leukemia Group B (CALGB) Prevention Group tested the reproducibility of RPFNA in a multi-institutional cross-sectional study.

Methods: Sixty-three high-risk women from five CALGB institutions (Duke, Ohio State, Roswell Park, Dana-Farber, and Vermont) underwent RPFNA from July 1, 2007 to June 30, 2008. Duplicate bilateral RPFNA was performed on each woman by a single investigator on a single day. Masood Cytology Index score was assessed by a single blinded cytopathologist.

Results: There was a high degree of statistical agreement in the Masood Cytology Index scores of duplicate RPFNA samples from the same breast, with a Spearman correlation coefficient of 0.8312 (p<0.0001). Importantly, while there was agreement in duplicate samples from the same breast, there was lack of agreement between duplicate samples from the opposite breast.

Conclusions: This multi-institutional study demonstrates that RPFNA is a highly reproducible measure of breast cytology in a cooperative group cross-sectional trial. RPFNA did not demonstrate a high degree of agreement between breasts, suggesting that breast cancer risk and progression may occur at different rates in individual breasts from a single woman.

These data provide important validation of the reproducibility of RPFNA in a multi-institutional cross-sectional study that included cohorts that varied in demographic composition. Important future directions will include a larger RPFNA cohort study and testing for the reproducibility of RPFNA samples with atypia before and after administration of chemoprevention agents.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A20.

Abstract A21: Lung cancer surveillance with CT scan and autofluorescence bronchoscopy

Thu, 07 Jan 2010 13:54:02 PST

Background: More than 75% of lung cancer patients are diagnosed at an advanced stage, when the survival rate is less than 15%. Sputum cytology, x-ray and CT scan have been evaluated as screening tools for early lung cancers, without much success. Auto-fluorescence bronchoscopy (AFB) has been recently shown to be effective in diagnosing central bronchial cancers. Combined surveillance with both spiral CT scan and AFB might help to increase the detection rate of the both central and peripheral lung cancers.

Methods: The study included 205 patients who were enrolled in the High Risk Lung Cancer Surveillance Cohort at Roswell Park Cancer Institute (RPCI) with at least 2 of the following risk factors: (1) radiographically documented pulmonary asbestosis or; (2) a history of previously treated aero-digestive cancer or; (3) > 20 pack years smoking history or; (4) COPD with an FEV₁ < 70% of predicted. Patients underwent spirometry testing, chest X-ray, sputum cytology, non-enhanced low dose spiral CT scan of the chest, and conventional white light/AF bronchoscopy with biopsy.

Results: A total of 20 invasive cancers/CIS were diagnosed in the 205 patients. Seven were diagnosed at baseline, 4 within 1 year of enrollment and 9 on follow up of more than 1 year. Between them, AFB and CT scan diagnosed all baseline cancers. Only 3/7 cancers were detected on x-ray screening and only 1/7 patients demonstrated atypia on sputum cytology. Overall, 17 invasive cancers and 3 CIS were diagnosed during the surveillance study. All the 3 CIS were identified only on AFB. Of the 17 invasive cancers, CT scan detected 15 cancers (88%) and AFB detected 5 of these cancers (30%). CT scan showed a 67% relative increase in sensitivity for detecting prevalent cancers and 3 times greater sensitivity for incident and prevalent cancers compared to x-ray screening. CT scan and AFB detected 19 of the 20 CIS/cancers (95%), whereas x-ray and sputum cytology together detected only 5/20 CIS/cancers (25%). The sensitivity of CT scan and AFB in diagnosing pre-malignant lesions and cancers improved by almost two and half times relative to x-ray and sputum.

Conclusion: The addition of AFB exam to yearly spiral CT scan of the chest could be a more efficient surveillance tool to identify early stage lung cancers, both in the central and peripheral lung. A greater efficiency and cost effectiveness can be achieved by limiting the use of the combination of AFB and CT scan in very high risk patients, selected based on their exposures and risk factors.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A21.

Abstract B21: Depression and quality of life in breast cancer survivors: 6-13 years postchemotherapy

ReyesGibby, C. C., Anderson, K., Morrow, P.K., Buzdar, A., Shete, S., Hassan, S. — Thu, 07 Jan 2010 13:54:14 PST

Background: Advances in breast cancer treatment have markedly prolonged survival time. This study examines the prevalence of and risk factors for depression and its impact on quality of life in breast cancer patients 6–13 years post-treatment.

Method: The Patient Health Questionnaire (PHQ-8) and European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 were mailed to assess depression and quality of life, respectively, in breast cancer patients who participated in clinical trials for paclitaxel chemotherapy treatment between 1994 and 2001.

Results: Two hundred forty patients participated (56% response rate). The years since treatment were between 6–13 years (mean= 7.9 and median=8). The mean score on the PHQ-8 scale was 4 points (SD=4.8; median=2.0) which decreased by years since treatment (Kruskal-Wallis, p< 0.001). Prevalence of depression (PHQ score ≥10) was 16%. Reports of depression decreased every year from treatment by as much as 30%. Depression had a negative impact on quality of life measures (function, symptoms, financial and global health), irrespective of years from treatment. Logistic regression showed that younger age (OR age in years= 0.92; 95% Confidence Interval [C.I.] = 0.86, 0.99; p<0.02), rheumatoid arthritis (OR=8.4; 95%C.I.=1.3–57.4; p<0.03) and years from treatment (OR=0.70; 95% C.I.=0.46–0.99; p<0.05) were significant predictors of depression.

Conclusion: While reports of depression decreased over the survival period, it remains a significant health concern for breast cancer survivors. The results suggest the need to monitor patients and provide resources for monitoring and treatment of depression within the clinical oncology setting.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B21.

Abstract A22: Spirometric surveillance for premalignant and malignant bronchial lesions

Thu, 07 Jan 2010 13:54:02 PST

Background: Chronic obstructive pulmonary disease (COPD) and lung cancer (LC) are diseases that share common risk factors. It has been reported that more than half of the patients diagnosed with LC also suffer from COPD. Although COPD is a well known risk factor for LC, the relationship between impaired lung function (LF) and the incidence and progression of pre-malignant lesions (PMLs) in the central airways is still unclear.

Methods: The study included 217 high-risk patients from a hospital-based lung cancer surveillance cohort who underwent bronchoscopy with endobronchial biopsy of suspicious lesions, at the Roswell Park Cancer Institute, Buffalo, New York. All patients had lung function measurement within 6 months preceding their baseline biopsy. Baseline histopathology diagnoses included 91squamous metaplasia (SM), 25 squamous dysplasia (SD), 1 in-situ carcinoma and 5 invasive bronchial carcinoma. Follow-up bronchoscopy and biopsy were performed on 69 patients. Sixteen patients had a progression of the baseline lesion to a higher grade. The relationship between the baseline LF measures and the incidence and progression of PMLs were examined using regression models.

Results: Patients with forced expiratory volume in 1 second percent predicted (FEV_1%) of <50% had 4.5 times greater risk of being diagnosed with PML/cancer, when compared to patients with FEV1% ≥80. Increased risk was noted for all grades of PMLs and cancers, with the risk being almost 8 times for squamous dysplasia [Odds ratio = 7.95; 95%confidence interval (CI) =1.77–35.6]. Similarly, FEV-1/FVC ratio of <50% was associated with 3 times greater risk of detecting a PML/cancer. When COPD was classified based on GOLD criteria, the patients with severe COPD had 2.7 times and 4.8 times greater risk of being detected with SM and SD, respectively. The risk persisted for SD even when an age standardized classification was used to define COPD. COPD patients also had a non-statistically significant 2.5 times greater risk of their baseline lesion progressing to a higher grade [Hazard Ratio 2.48 (95% CI 0.65 – 9.41), p-value - 0.18)]. The mean time to progression from a lower grade lesion to a higher grade was 27 months for patients with COPD and 50 months for patients without COPD.

Conclusion: Impaired LF can be a good predictor of occurrence and progression of PMLs in central airways of high risk patients. Spirometric measurement of lung function can be used as an additional tool for identifying target populations in need of more aggressive LC surveillance.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A22.

Abstract B22: Factors associated with community members' participation in a research registry

Skinner, C. S., Tiro, J. A., Bishop, W. P., Bruce, C. — Thu, 07 Jan 2010 13:54:14 PST

Introduction: It is important to provide community members - especially those from traditionally underserved groups - with equitable opportunities to participate in research. Volunteer registries have been employed to generate pools of potential participants. However, we know little about factors associated with participation in such registries.

Procedures: Bilingual research staff approached persons aged 18 and over attending the VIVA Dallas! Hispanic Exposition August 8–9, 2009, asking if they would complete a one-page health topics survey and receive, in return, a water bottle with our cancer center's logo. The survey, available in Spanish and English, measured age, sex, marital and parental status, race/ethnicity, country of birth, acculturation (Marin and Marin's 4-item scale), insurance coverage, access to and place of usual health care, and health topics of concern. One item asked, "May we contact you in the future for research studies?" and provided space for contact information for those who checked "yes".

Data: The 1,183 survey completers were 64% female, 77% Hispanic, and 68% married or living as married. Most were parents (69%), ≤ 50 years old (68%), and were born outside the US (57%). Scores on the 4-item acculturation scale classified 45% with lower acculturation and 36% with higher acculturation; scores could not be calculated for the 19% with missing data. Some type of insurance coverage was reported by 40% (with 19% missing) and 43% reported access to usual health care (with 17% missing). Most frequently cited health topics of concern were diabetes (53%), healthy eating (32%) and managing stress (31%). Cancer was mentioned by 20%, with breast being the most-cited cancer type. Overall, 63% indicated agreement to be contacted for future studies. Agreement was significantly associated (all p<.01) with: age less than 50, female sex, having ever been married, being the parent of at least one child, Hispanic ethnicity, birth outside the US, lower acculturation score, no insurance coverage, and no place for usual health care.

Conclusions: Among attendees at Dallas' largest Hispanic community event, interest in completing the survey was high. The majority of survey completers (63%) agreed to be contacted for future studies. People most likely to agree to future contact represented groups often not included in studies - those born outside the US, with lower acculturation scores, and no health insurance or source of regular health care. Use of registries generated through community events such as VIVA Dallas! may help to address disparities in access to and participation in cancer control research.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B22.

Abstract A23: PSA testing and prostate cancer mortality in an Asian population: Linking prevalence of elevated PSA and mortality rate

Chiang, P.-H., Wen, C.-P. — Thu, 07 Jan 2010 13:54:02 PST

Background: In Asian populations, prostate cancer mortality (PCM) has been increasing with the increasing use of PSA testing.

Objectives: 1) To establish prevalence of elevated PSA at different cutpoints in Taiwan and to assess the predictive relationship of PSA with PCM. 2) To compare PCM between those with PSA tested and not tested from a cohort study.

Methods: Among the cohort, 231,937, who received standard medical screening examination between 1994 and 2006 at a private screening clinic, 46,951 subjects, aged at least 50 years old, had PSA test results. Age and education were adjusted to those of Taiwan to arrive at national PSA prevalence. PCM was compared between the PSA untested (38,596) and PSA tested group (24,176), with the latter including those with a self-reported history of prostate cancer (1,675).

Results: National prevalence of PSA was 8.8% (threshold at 4) and 1.9% (threshold at 10). With national mortality rate at 30.1/100,000, the chance of dying in ten years was 3.4%, 15.8% or 27.9% among those above threshold at 4, 10, or 15, respectively, yielding false positives rates, with mortality as the outcome, 96.4%, 84.2% or 72.1%, and false negative rates, 12%, 33% or 50%, respectively. Having PSA tested, when compared with not tested, was not associated with decreased mortality from prostate cancer, even though PSA tested group, a higher educational class, had significantly decreased mortality from all cause. Increasing PSA levels were associated with increasing HRs.

Conclusion: PSA value above standard threshold of 4 is common in this Asian population (one out of 11 for age 50 and older), but only one in 29 tested positive was expected to die from prostate cancer within the next 10 years. This 10-year probability increased when threshold was 10 (1/6) but was still low. The high false positive rate of PSA (97%) and the harm associated with intervention among Asians should be communicated to the elderly patients, in view of the particularly low mortality rate of this cancer.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A23.

Abstract B23: Evaluating an intervention to improve perceptions of cancer clinical trials among minority communities in South Carolina

Thu, 07 Jan 2010 13:54:14 PST

Objective: Cancer mortality rates for African Americans in South Carolina are among the highest in the nation. However, African Americans are less likely than other groups to participate in cancer clinical trials. Results of previous investigations have shown that their low participation rates are related to negative perceptions of trials. We conducted a community based cancer clinical trials education intervention to improve perceptions of cancer clinical trials in this population.

Methods: The study was conducted at eight different sites in six counties in South Carolina. The intervention consisted of a 30-minute cancer clinical trials educational presentation developed by the National Institutes of Health/National Cancer Institute. The intervention was part of a larger 3.5-hour education program aimed at increasing general cancer knowledge, prostate cancer knowledge, and perceived self efficacy in patient-physician interaction among minority populations in South Carolina. Study participants were recruited by community partners in each locale where the training sessions were conducted. A pre- and post-intervention survey was administered immediately before and after the intervention was delivered at each site. The survey instrument included seven items. Sample items include the following: Do you think that patients should be asked to take part in medical research? Would you be prepared to take part in a study comparing different treatments? Would you be prepared to take part in a study where treatment was chosen at random?

Results: The study sample consisted of 164 predominantly African American participants. One-hundred and twenty-five (78.6%) of the 159 participants who provided data on race were African American, 19 (12.0%) were Caucasian and 15 (9.4%) were Native American. The majority of the 160 participants who provided data on age were ages 50+ years (62.5%). The majority of the 154 participants who reported their income had an annual household income > = $40,000 (53.8%). For each of the seven survey items assessing perceptions of cancer clinical trials, 74%, 69%, 56%, 49%, 61%, 50% and 58% of the participants, respectively, changed to more favorable responses on the post-test vs. pre-test. All results were statistically significant at the p<0.001 level.

Conclusions: Providing cancer clinical trials information to African American community members positively influenced their trial perceptions. Future research could incorporate a longer follow-up assessment period.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B23.

Abstract A24: Diagnostic performance of PET and PET/CT for cancer detection in asymptomatic volunteers

Thu, 07 Jan 2010 13:54:02 PST

Purpose: We investigated retrospectively the diagnostic performance of ¹⁸F-fluorodeoxyglucose positron emission tomography (PET) and PET/CT for cancer detection in asymptomatic volunteers.

Materials and Methods: This study consisted of 5091 whole-body PET or PET/CT underwent as a part of annual health check-up at one hospital from 1998 to 2008. Annual health check-up program of the hospital includes comprehensive blood tests, urinalysis, stool examination, chest X-ray, mammography, abdominal sonography, and gastrofiberscopy. Lung CT, brain MRI, breast sonography, thyroid sonography, or colonoscopy were performed in some individuals. To find the incidence of cancers, medical records of the subjects were thoroughly reviewed for a follow-up period of one year. Cases with cancer detected before PET or PET/CT scanning were excluded. The pattern of formal readings of PET and PET/CT were analyzed to assess the sensitivity and specificity for cancer detection. The stage and histopathology of the cancers were evaluated in relation to detection or missing by PET.

Results: Eighty-six cancers (1.7%, 86/5091) were diagnosed within one year after PET or PET/CT. Sixty-nine (1.5%, 69/4503) cancers were detected in men and 17 (2.9%, 17/588) cancers were detected in women. They included 33 thyroid cancers, 10 prostate cancers, 9 stomach cancers, 9 colorectal cancers, 7 lung cancers, and other cancers. PET and PET/CT in combination had a sensitivity of 53.5% (46/86) and a specificity of 81.1% (4061/5005) for cancer detection. Positive predictive value was 4.6% (46/990) and negative predictive value was 99.0% (4061/4101). PET only had a sensitivity of 51.3% (40/78) and a specificity of 81.4% (3625/4452), and PET/CT only had a sensitivity of 75.0% (6/8) and a specificity of 78.8% (436/553) respectively. A total of 44 PET negative cancers (little FDG uptake) include 13 thyroid cancers, 7 prostate cancers, 7 colorectal cancers, 4 stomach cancers, and others. When comparing tumor stages, early cancers (stage 0 or 1) comprised 59% (26/44) of PET negative cancers, and 40% (17/42) of PET positive cancers. However, there were no statistically significant differences in cancer site, stage and histopathology between PET positive cancers and PET negative cancers. In 19.3% of formal readings of PET and PET/CT, further evaluation was recommended to exclude malignancy or significant disease. Commonly recommended sites for further evaluation were head and neck, upper gastrointestinal tract, thyroid, lung and mediastinum, and lymph nodes. Diagnostic modalities recommended for further evaluation were physical examination, esophagogastroduodenoscopy, CT, biopsy, and others.

Conclusions: PET and PET/CT showed a moderate performance for detecting cancers in asymptomatic adults in this study. More experience and further investigation are needed to overcome limitations of PET and PET/CT for cancer screening.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A24.

Abstract B24: Evaluating an intervention to increase cancer knowledge in minority communities in South Carolina

Thu, 07 Jan 2010 13:54:15 PST

Objective: Cancer mortality rates for African Americans in South Carolina are among the highest in the nation. Lack of knowledge likely contributes to cancer disparities. To address this issue, we conducted a community based cancer education intervention to improve cancer knowledge among African American and other minority communities in South Carolina.

Methods: The study was conducted at eight different sites in six counties in South Carolina. The intervention consisted of a 3.5-hour evidence-based cancer education program in which a 3-hour component focused on general cancer knowledge and a 30-minute component focused on prostate cancer knowledge. Pre- and post-intervention surveys were administered immediately before and after the intervention was delivered at each site. The maximum score for the 31-item cancer knowledge instrument was 31. Prostate cancer knowledge was assessed using a 10-item instrument, with a maximum score of 10. Perceived self-efficacy in patient-physician communication about cancer was measured by a 5-item scale with a maximum score of 5. We hypothesized that the intervention would result in increases in general cancer knowledge, prostate cancer knowledge, and perceived self-efficacy in patient-physician interaction.

Results: The study sample consisted of 164 predominantly African American participants. One-hundred and twenty-five (78.6%) of the 159 participants who provided data on race were African American, 19 (12.0%) were Caucasian and 15 (9.4%) were Native American. The majority of the 160 participants who provided data on age were ages 50+ years (62.5%). The majority of the 154 participants who reported their income had an annual household income > = $40,000 (53.8%). The general cancer knowledge pre-test score had a mean of 26.2 with a standard deviation (SD) of 3.7 and a mean post-intervention increase of 2.04 points (p<0.01). The mean pre-test prostate cancer knowledge score was 7.3 (SD 2.0). The mean increase in prostate cancer knowledge was 0.48 points (p<0.01). Due to a ceiling effect, most sites showed little increase in perceived self-efficacy in patient-physician interaction (PEPPI). The exception was the Native American site, which had a larger increase in each PEPPI question from pre-test to post-test than the other sites.

Conclusions: General cancer knowledge scores and prostate cancer knowledge scores increased following the intervention. Future interventions could incorporate more intensive (i.e., repeated sessions) cancer education programs as well as an assessment of the impact of the interventions on the communication dynamics between patients and their health care providers.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B24.

Abstract A25: Public and provider awareness and use of a CA-125 test for ovarian cancer

Stewart, S. L., Rim, S. H., Gelb, C. A. — Thu, 07 Jan 2010 13:54:02 PST

Introduction: CA-125 is a serum marker approved for detecting recurrent ovarian cancer in women with a personal history of ovarian cancer. Several large trials have investigated the use of CA-125 (alone or in combination with transvaginal ultrasound [TVU]) as a screening test for ovarian cancer. However, this test has generally been associated with a low positive predictive value and trials have concluded that screening asymptomatic women in the average risk population with CA-125 is not beneficial. Still, there remains widespread discussion and marketing of ovarian cancer screening tests that include CA-125. Since little is known about public and provider awareness of CA-125, the objective of this study was to measure women's familiarity with the CA-125 test, and clinician beliefs about the effectiveness of screening for ovarian cancer with CA-125 in the United States.

Methods: In 2008, CDC funded the collection of data as part of its national awareness campaign, Inside Knowledge: Get the Facts About Gynecologic Cancer. Several questions related to CA-125 were included as part of a standardized, survey administered annually in the contiguous United States by Porter Novelli. The HealthStyles survey included 2,991 female respondents age ≥ 18 years, and the DocStyles survey included 1,250 physician respondents of family/general practitioners (n=510), internists (n=490), and obstetrician/gynecologists (n=250). Participant responses to CA-125-related questions for the HealthStyles survey were weighted to match the demographic distribution of the general population. Chi-square tests were used to assess differences with the p-value set to 0.05.

Results: Overall, most women (56%) had not heard of the CA-125 test, 29% had heard of it, and 15% were unsure. Demographic characteristics generally were similar for women who had not heard of the CA-125 test, except that women who had heard of the test more often were over age 45 (58% vs 37%) (p<0.0001) and were peri- or post-menopausal (54% vs 35%) (p<0.0001), compared to women who had not heard of CA-125. Few women (12%) had ever had a CA-125 test. About 15% of women who reported being "very concerned" about getting ovarian cancer also reported having had a CA-125 test. In the DocStyles results, the majority (53%) of physicians said that both CA-125 and TVU are effective screening tests for ovarian cancer. A greater proportion of OB/GYNs (57%) reported neither CA125 nor TVU were effective as screening tests for asymptomatic women in the average risk population than family/general practitioners (34%) or internists (30%) (p<0.0001).

Conclusions: The large percentage of physicians who believe CA-125 is an effective screen for ovarian cancer signals the need for improved education. Educational efforts geared toward the public and providers that include both lack of evidence for screening with CA-125, as well as the potential harms of false-positive CA-125 tests should be a priority for public health programs and awareness campaigns.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A25.

Abstract B25: Feelings associated with research participation influence willingness to take part in epidemiological studies

Thu, 07 Jan 2010 13:54:15 PST

Purpose: Cancer epidemiology research often involves members of the public as "healthy controls." Encouraging broad participation in cancer research is a key concern, particularly for research involving members of the general public who may have lower motivation to take part. Most work of individuals' decisions about study participation has focused on expected utility constructs, examining the benefits participants see to participating and the barriers that make participation less likely. Little attention has been paid to emotional decision-making processes in this context. Such emotional processes (e.g., fear about procedures, anger about historical research misconduct) may guide decisions about participation. The purpose of this study was to examine the relation of cognitive and affective decision-making factors to individuals' participation in a epidemiologic study involving both questionnaire completion and blood collection.

Method: Participants (N=46) were community adults in Niagara Falls, NY who were taking part in an educational program about cancer-related research participation. Both prior to and following the educational program, we assessed participants' beliefs about the expected utility of participating in studies that involve questionnaire completion and studies that involve blood collection, the positive and negative feelings they associated with taking part in each type of study, and their willingness to take part in each type of study. Following the post-program questionnaire, participants were offered the opportunity to take part in an epidemiological study in which they could complete a questionnaire, provide a blood sample, or do both.

Results: Both willingness to participate in studies and actual participation was primarily predicted by the feelings individuals associated with research, for both blood draw studies and questionnaire studies, those with more negative feelings about participation were less like to report willingness to take part in the study; questionnaire willingness B=–1.21, p<.05; blood willingness B=–0.97, p<.05. For blood draw studies, affective associations also predicted actual participation; B=–1.15, p<.05.

Discussion: The feelings individuals have about research participation played a central role in determining participation. Both research to better understand determinants of research participation and interventions to increase participation should consider affective factors.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B25.

Abstract A26: CEA and CA 19-9 as biomarkers for prevention of gall bladder cancer

Kapoor, V. K., Agrawal, V., Goel, A., Krishnani, N., Pandey, R., Agrawal, S. — Thu, 07 Jan 2010 13:54:02 PST

Objective: Gall bladder cancer (GBC) is the commonest biliary tract cancer worldwide. It is the commonest gastro-intestinal cancer in women in northern India; it is common in Native American Indian people also. GBC is usually associated with gall stones (GS) and chronic cholecystitis (CC); xantho-granulomatous cholecystitis (XGC) is a variant of CC. Most patients with GBC are diagnosed at an advanced stage and overall prognosis is poor. Prophylactic cholecystectomy in patients with asymptomatic GS can prevent GBC, but it can not be advised in everyone with GS. There is a need to identify some bio-markers for early diagnosis and prevention GBC.

Materials and Methods: We evaluated the immuno-histo-chemical (IHC) expression of carcino-embryonic antigen (CEA) and carbohydrate antigen (CA) 19-9 in histo-pathologically confirmed GBC (n=51), CC (n=68), XGC (n=42) and normal GBs removed during operations on bile duct, liver and pancreas (n=10). IHC was performed using mouse monoclonal primary antibodies for CEA (Clone II-7, 1:100, Dako) and CA 19.9 (Clone 116-NS-19-9, 1:100, Dako) using labeled Streptavidin Biotin Peroxidase method. Intensity of staining was recorded as absent (0), mild (1), moderate (2) and intense (3) while the percentage of nuclei stained were scored as absent/<5% (0), >5 <10% (1), 10–50% (2) and >50% (3). The total score was calculated by adding the intensity score and the percentage score and ranged from 0–6. A score of ≥3 was considered as positive.

Results: CEA expression was present in 42/51 (82%) of GBC - it was apical in 13, focal cytoplasmic in 15 and diffuse cytoplasmic in 14 cases. CEA expression was seen in 18/68 (27%) of CC - it was apical in all 18 with focal cytoplasmic in 9. CEA expression was seen in 4/42 (10%) of XGC - it was apical in all 4; many cases with XGC, however, did not have epithelium. All 10 normal GBs showed apical CEA expression. Diffuse cytoplasmic staining of CEA was seen in only GBC and was not seen in CC, XGC and normal GBs. CA 19-9 expression was seen in 38/51 (75%) of GBC - all cytoplasmic; all 13 CA19-9 negative GBCs were high grade on histopathology. All CC, XGC and normal GBs showed apical and diffuse cytoplasmic positivity for CA 19-9.

Conclusion: Tumor markers such as CEA and CA 19-9 can be used to screen patients with asymptomatic GS to identify a sub-group with higher risk to develop GBC who can then be offered prophylactic cholecystectomy for secondary prevention of GBC.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A26.

Abstract B26: Cancer prevention clinical trials: Assessing for disparities in recruitment in Hawaii

Bantum, E. O., Cheng, I., Cassel, K., Ka'opua, L. S., Berenberg, J. — Thu, 07 Jan 2010 13:54:15 PST

A key concern of clinical trials of cancer is improving the participation rates of minority populations that are often underrepresented and have high rates of disease. In particular, identifying the underlying factors that contribute to the underrepresentation of minorities is essential for developing improved recruitment strategies—this is especially important for prevention trials of cancer that may ultimately translate to reducing the burden of disease in the population. To identify disparities in cancer prevention trials in Hawaii, we compared participation rates across racial/ethnic groups for breast and prostate cancer prevention trials. We then examined the methods of recruitment for each trial. The following four prevention trials were included in our assessment: the Breast Cancer Prevention Trial (BCPT), the Prostate Cancer Prevention Trial (PCPT), and the Study of Tamoxifen and Raloxifene (STAR). We identified gender differences in the participation rates of Native Hawaiians. Among 272 female participants in the STAR and BCPT trials, 10.3% (n = 28) were Native Hawaiian. In contrast, among 213 male participants in the SELECT and PCPT studies, only 5.2% (n = 11) were Native Hawaiian. The ethnic breakdown of the state during the approximate time of recruitment (2000) was as follows: African American 2.4%, Caucasian 24.3%, Chinese 7.4%, Filipino 16.5%, Hawaiian 19.8%, Japanese 18.9%, Korean 2.4%, Other ethnicities 8.4% (US Census, 2000). In these trials differing recruitment strategies were used. For example, in the SELECT trial a targeted direct mailing campaign to men 50 years of age or older (27.6% of sample), whereas in the STAR trial physician referral was the primary source of participation (59.0%). While these analyses do not speak to what specific strategies were most beneficial for a given racial/ethnic group, it is important to note that there was a higher likelihood of recruiting Native Hawaiian women when they were referred to the trial by their physician. Understanding the importance of the relationship between the study participant and the referral agent is just one strategy that will be examined in our future work. Researchers attempting to recruit African Americans at a rate of 20% for clinical trials (Cook at al., 2005) found that a diligent effort aimed at expanding the eligibility recruitment for African American men and the provision of more resources to particularly target this group were strategies that helped decrease disparities in recruitment. Given the multi-ethnic and multi-cultural nature of Hawai'i there are a wide range of practices and beliefs that need to be considered and incorporated in clinical trial recruitment. Our ultimate goal is to improve the participation rates of Native Hawaiians in clinical trials of cancer prevention.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B26.

Abstract B27: Social representations of human papillomavirus (HPV) in Bogota, Colombia: A qualitative study

Thu, 07 Jan 2010 13:54:15 PST

Introduction: Identifying DNA of Human papillomavirus (HPV) among asymptomatic women has been proposed as a new screening method for cervical cancer control. Screening programs must be preceded by health education. Traditionally, health education is based on scientific information without considering any community cognitive processes. This paper studies HPV social representations constructed upon social interaction between men and women over 25 years of age, living in Bogotá, Colombia. The outcomes will be used as groundwork for an education strategy to promote HPV testing within a primary screening program.

Methods: It is a qualitative study based upon symbolic interaccionism. Inter individual communication is precisely the ground where a framework of references is constructed and social representations emerge. Focus group selection was planned using a theoretical population sample. Twelve focus groups were held with 124 men and women from diverse educational status. Information source analysis and graphic analysis of significants were performed.

Results: Social representation of HPV involves a series of figurative nuclei that arose from associated meanings linked to scientific information. While women focused on symbols associated to contagion; men focused on its venereal character. Negative feelings were expressed particularly among women with a history of one sexual partner. Figurative nuclei also included long-term uncertainty, need or urgent treatment and feelings of imminent death that are associated to cancer and chronic sexually transmitted infections. The social representation burden of HPV impeded many participants from clearly understanding written information about HPV transmission, clearance and cancer risk.

Conclusion: HPV social representations are built into a whole framework of values, which must be deconstructed to allow women full participation in HPV screening programs and to prevent psychosocial adverse effects. Delivering scientific information may not be enough for achieving this purpose. Shared decision making is a communication strategy that must be promoted for anticipatory discussion on HPV-DNA testing to be able to deconstruct different values and meanings particularly its association with promiscuity and venereal diseases.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B27.

Abstract A28: Improving detection through SELF (selective excitation light fluorescence) imaging

MacAulay, C., Khojasteh, M. — Thu, 07 Jan 2010 13:54:02 PST

The use of fluorescence imaging and spectroscopy for the detection of early neoplastic epithelial lesions has been well established, with clinically adopted devices in for use in the lung (Onco-LIFE, SAFE-1000, etc), the oral cavity (VELScope and Identaf 3000) and others in development for the cervix and dermatology. Primarily these imaging technologies make use of fluorescence excitation illumination of a single wavelength (predominately in the near UV to blue wavelength ranges) and differentiate between normal and not normal tissue based upon intensity changes and spectral shifts in the emitted tissue autofluorescence (not normal -darker with less green or blue relative the red fluorescence).

SELF imaging makes use of a multitude of illumination wavelengths to specifically couple to the action spectra of the fluorophores within the tissue to enhance the differentiation between tissue states, fluorophores and their immediate environment. This methodology makes use of the different absorption spectra (action spectra) of different fluorophores or similar flourophores in different environments. Conventionally this can be done through the sequential illumination with many different excitation wavelengths and sequential image capture, to collect a hyperspectral excitation image data cube followed by some form of spectra unmixing to resolve the individual targets (components) contributing to the image. Each target is identified by a unique weighted sum of pixel intensities across the excitation wavelengths in the data cube.

Through the use of a programmable light source such as the OneLight (OneLight Corp.) in which not only the wavelengths of the illumination light, but their individual intensities (alone or in combination) can be selected under computer control it is possible to not only rapidly illuminate with separate excitation wavelengths but to illuminate with a collection of weighted (each wavelength has a different selected intensity) spectra to specifically couple to selected fluorescence targets (specific fluorophores or fluorophores in specific local environments). Thus instead of needing to illuminate with a series of 10 separate excitation wavelengths and collect separate 10 images on can illuminate with a few (2–3) weighted profiles of excitation wavelengths and collect a few (2–3) images, the number of spectra used (images collected) determines the number of targets differentiated. In this fashion it is possible to detect in an image many more specific flourophore types than with conventional fluorescence imaging. SELF imaging in microscopy, wide field macroscopic imaging and ex vivo and in vivo imaging has been demonstrated and will be presented.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A28.

Abstract A29: Rectal mucosal polyamine and PGE2 levels and risk of colorectal adenomas in a phase IIb/III trial of combination difluoromethylornithine (DFMO) plus sulindac

Thu, 07 Jan 2010 13:54:02 PST

Background: The pharmacologic targeting of polyamines and prostaglandin E2 (PGE2) has proven efficacy for colorectal adenoma prevention. However, the contribution of these analytes as biomarkers of drug response has not been investigated.

Methods: We analyzed the relationships between rectal mucosal levels of polyamines (spermidine, spermine, and putrescine) and PGE2, treatment, and risk of adenoma within the context of a phase IIb/III trial of combination difluoromethylornithine (DFMO) plus sulindac for the prevention of colorectal adenoma.

Results: We detected no differences in the change in PGE2 levels between the two groups for any time points, but we show a statistically significant decrease in spermidine:spermine levels and in putrescine levels in the DFMO/sulindac group at 12 and 36 months compared to the placebo arm. When we asked whether or not change in polyamine or putrescine levels was associated with adenoma recurrence in the treatment arm only, we found no difference in the rate of metachronous events by change in polyamine or PGE2 levels in the treatment arm. We also found no evidence that polyamine or PGE2 levels were associated with risk of adenoma when we restricted the analysis to the placebo arm only. Of interest, we found that participants with low baseline spermidine:spermine levels who received DFMO/sulindac achieved a significantly greater benefit from treatment (RR = 0.15, 95% CI = 0.06 to 0.40) than those with high baseline spermidine:spermine receiving drug (RR = 0.50, 95% CI = 0.27 to 0.92).

Conclusions: DFMO/sulindac significantly suppressed the production of rectal mucosal polyamines, but the magnitude of change was not predictive of response to intervention. This was likely due to the large effect of DFMO/sulindac on adenoma recurrence. We found no evidence in the placebo arm that baseline polyamine or PGE2 were associated with the risk of developing adenoma. The modulating effect of baseline spermidine:spermine levels on metachronous adenoma, in those individuals receiving the drug combination, provides evidence of differential agent-effectiveness by steady-state polyamine levels that should be investigated in future studies.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A29.

Abstract B29: African American men never or rarely screened for prostate cancer

Williams-Brown, S. D., Ross, L. E., Hinton, L. — Thu, 07 Jan 2010 13:54:15 PST

Introduction: Prostate cancer is the leading cancer and the second leading cause of cancer deaths among men in the United States. African American (AA) men are at greater risk than Caucasian American (CA) and other men in both incidence and mortality related to prostate cancer. Incidence among AA men is about 60 percent greater and mortality about 240 percent greater than in CA men. AA men also have a greater likelihood of presenting at higher stage and grade with poorer health and other outcomes. Little is known about factors related to AA men who never or are rarely screened for prostate cancer using the DRE and PSA tests. The purpose of this study was to explore prostate cancer screening practices of AA men and to examine demographic characteristics that are associated with AA men who never or are rarely screened.

Methods: AA men age 40 or older were asked questions about their knowledge, awareness, and attitudes regarding prostate cancer and prostate cancer screening using DRE and PSA. The study used a convenience sample of 448 AA men 40 years and older residing in the Southeastern U.S. Data were self-reported survey responses and analyzed using SAS.

Results: The majority of study participants were married (52%), had some college or technical training (78%), and employed (59%). Over 90% of the AA men had prior knowledge of DRE and 77% were aware of the PSA test. The percentage of AA men who had not had prostate cancer screening in over 5 years or not at all (never or rarely screened) was 33% for DRE and 34% for PSA. Demographic factors related to never or rarely screened for DRE were: being single, younger age, no health insurance, and higher levels of education. Factors related to never or rarely screened for PSA were: younger age, no health insurance, and higher levels of education.

Conclusions: Since AA men have greater burden of prostate cancer among men, it is surprising that despite knowledge and awareness of screening and increased levels of education, approximately one-third of the men in this sample had neither a DRE or PSA ever or in 5 or more years. Additional studies are needed to further explore the relationship between prostate cancer knowledge and awareness, education attainment, and prostate cancer screening in AA men.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B29.

Abstract A30: Cost-effectiveness analysis of HER2 testing methods in adjuvant treatment of HER2 breast cancer

Ashok, M., Griffin, P., Halpern, M. — Thu, 07 Jan 2010 13:54:03 PST

Background: Trastuzumab is a targeted therapy indicated for the treatment of HER2-postive breast cancers, an aggressive form of this disease. HER2 status can be assessed using two tests: florescence in situ hybridization (FISH), which tests for HER2 gene amplification; or immunohistochemistry (IHC), which tests for HER2 protein overexpression. There is considerable debate regarding which of these tests should be used for HER2 detection due to differences in cost, accuracy, and health outcomes.

Objective: To compare the outcomes and cost effectiveness of FISH and IHC for HER2 testing in breast cancer.

Design: Based on data from outpatient electronic medical records, decision models were designed for FISH, IHC and No Test scenarios (in which all patients received trastuzumab without being tested). Each model considered costs and health outcomes. Treatment possibilities included chemotherapy (with or without trastuzumab), radiation therapy, and surgery. Cost for trastuzumab adverse events were also included. Point estimate analysis and Monte Carlo simulations (varying false positive rates of tests) were used to determine results.

Data: A hypothetical cohort of 100,000 female breast cancer patients. Interventions: Testing with FISH or IHC followed by subsequent trastuzumab treatment when indicated (i.e., when the test result is positive for HER2), which included false positive and false negative results.

Outcome Measures: Medical costs, Quality Adjusted Life Years (QALYs) and percentage of patients correctly tested (true positives who test as positive and true negatives who test as negative).

Results: The expected per-patient costs of the No-test model, IHC model and FISH model were $166,360, $72,405, and $64,626 respectively. The expected values of total QALYs experienced by IHC and FISH groups were essentially identical. Using Monte Carlo analysis to vary test accuracy rates also indicated decreased costs and improved outcomes for FISH. In addition, FISH had increased levels of correct HER2 status detection when compared with IHC: if tested with FISH rather than IHC, there was a 3.58% increase in probability that a patient who is HER2 positive will be diagnosed as positive and a 15.66% increase in probability that a patient who is HER2 negative will be diagnosed as negative.

Conclusions: FISH should replace IHC as the preferred method of choice for HER2 testing. This would result in increased cost-effectiveness of testing and treatment for HER2 breast cancer.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A30.

Abstract B30: Patient navigation for cervical cancer in Kentucky: Baseline results

White, C., Dignan, M., Slone, S., Gomez, M., Jones, K. — Thu, 07 Jan 2010 13:54:15 PST

Background: Although morbidity and mortality rates are low compared to other types of cancer, cervical cancer remains a high priority for the following reasons: 1) invasive cervical cancer is a disease that could be prevented in nearly all cases, with greater use of the Pap test; 2) the Pap test is a well-established, low cost, widely available screening test that should present minimal barriers to its use; and 3) despite our ability to prevent and treat cervical cancer, the burden of cervical cancer morbidity and mortality continues to be higher among low-income women with limited education, many of whom reside in rural areas. Despite public health recommendations for cervical cancer screening and follow-up of abnormal Pap test results, adherence is still low among rural Appalachian women in Kentucky. In response to this concern, the University of Kentucky Prevention Research Center is implementing a National Cancer Institute-funded project that is integrating patient navigators (PN) in cervical cancer screening programs in several rural health departments.

Goal: To reduce the disproportionate burden of cervical cancer experienced by rural Appalachian women in Kentucky.

Objectives: To: 1) improve our understanding of the barriers to follow-up; 2) recruit, train, and utilize lay health workers as PNs in cervical cancer screening programs; 3) increase the proportion of women who adhere to recommended follow-up; and 4) evaluate the efficacy of the intervention.

Method: Intervention activities are as follows: 1) nurse case managers refer patients with abnormal pap tests to PNs in selected local health departments in Big Sandy, Lake Cumberland, and Kentucky River Area Development Districts; 2) PNs enroll patients in the study; 3) study participants complete a baseline interview; 4) PNs provide navigation services including outreach, education, and support; 5) PNs conduct follow-up interviews; and 6) PNs document follow-up recommendations, barriers, patient needs, and specific actions taken to ensure adherence to follow-up recommendations.

Evaluation: To assess the efficacy of the intervention, outcome data will be collected from health department records in intervention and control counties.

Findings: The total number of referrals to date is 600. Among the referrals: 82 (14%) were ineligible (patient less than 18 years, refused services, dropped by health department for non-compliance, or lost to follow-up); 379 (63%) were offered enrollment; and enrollment is pending for 139 (23%). Among those offered enrollment, 297 (78%) agreed to participate in the study. Additional preliminary findings will be presented including reason for referral, characteristics of women enrolled, patient needs, adherence to follow-up, etc.

Conclusions: The program creates a unique opportunity to support rural cervical cancer screening programs, ensuring women obtain their recommended follow-up care through the support of PNs.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B30.

Abstract A31: The role of microRNA 125a-3P in the pathogenesis of lung cancer

Thu, 07 Jan 2010 13:54:03 PST

Tobacco exposure results in specific oncogene and tumor suppressor gene alterations in lung epithelial cells that often lead to lung cancer development. Activating point mutation of the K-ras proto-oncogene is one of the most frequently occurring genetic changes found in lung cancer both in active and former smokers. Understanding how K-ras mutations mediate the malignant phenotype may yield more effective prevention and diagnosis strategies to be applied to individuals at elevated risk for lung cancer. Micro RNAs are a class of short (19–24 nucleotides) noncoding RNAs that play a critical role in posttranscriptional gene regulation. A rapidly developing literature supports an important role for micro RNAs in the regulation of lung carcinogenesis and tumor progression. In order to better understand the role of micro RNAs in the K-ras-mutated bronchial epithelium, we utilized hTERT- and Cdk4-immortalized human bronchial epithelial cells (HBEC) expressing mutant Kras^V12. We next generated the micro RNA profile (TaqMan miRNA array v.2, Applied Biosystems, Foster City, CA), gene expression profile (Affymetrix U133 plus 2 array), and protein expression profile (50-plex inflammatory marker panel) of the K-ras mutated and vector control HBECs. We found that the micro RNA miR-125a-3p was significantly suppressed in K-ras-mutated HBECs compared to the vector control cells. We then evaluated basal expression of miR-125a-3p in both HBECs and NSCLC cell lines containing mutated K-ras by real time RT-PCR. Both K-ras-mutated HBECs and NSCLC cell lines expressed low levels of miR125a-3P. In order to further evaluate the role of miR-125a-3p, we stably expressed this micro RNA in K-ras-mutated HBECs. Our results indicate that miR-125a-3p expression down-regulates several tumor-promoting factors, including Gro-, HGF, VEGF, GM-CSF, and G-CSF. Further studies revealed that suppression of Gro- and HGF, but not VEGF, is regulated at the level of mRNA expression. Overexpression of miR-125a-3p suppressed proliferation of the K-ras-mutated HBECs but did not alter the proliferation of the vector control HBECs. Based on these findings, we anticipate that loss of miR-125a-3p may have a broad impact in the bronchial epithelium that harbors K-ras mutations, potentially regulating cellular proliferation, angiogenesis and inflammation. Further exploration is required to evaluate the role of this micro RNA and its downstream effects as potential screening tools and targets of prevention and therapy in the setting of K-ras-mutated lung cancers.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A31.

Abstract A32: Identification of biomarkers in normal human breast cells regulated by the cancer preventive rexinoid LG100268

Thu, 07 Jan 2010 13:54:03 PST

Background: Drugs targeting estrogen signaling or production have become useful in preventing estrogen receptor-positive breast cancers, but not estrogen receptor-negative (ER-negative) breast cancers. Our laboratory has demonstrated that rexinoids prevent ER-negative mammary tumors in transgenic mice by 90%. However, since these agents are not 100% effective, we are investigating the mechanism by which rexinoids prevent cancer to develop more efficacious prevention strategies. We hypothesized that by identifying molecules regulated by the rexinoid LG100268, future chemopreventive agents could be developed to target these molecules alone or in combination with rexinoids to totally prevent breast cancer development. To investigate this hypothesis we utilized an Affymetrix genome array to identify biomarkers regulated by LG100268.

Methods: Cell counts were used to confirm rexinoid-induced growth suppression in normal human mammary epithelial cells (HMECs). TUNEL analysis was conducted to determine whether the growth suppression was a result of induction of apoptosis. We conducted Affymetrix analysis using 10ug total RNA from HMECs treated with 0.1% vehicle or 1uM LG100268 for 1 hour or 24 hours. cRNA was hybridized with the GeneChip® Expression Analysis Array (U133) from Affymetrix. Results were analyzed using Microarray Suite 5.0 (Affymetrix). Genes to be considered for further confirmation had a fold change of > 1.5 or < 0.8 (p < 0.05) for up- or down-regulated genes, respectively. Geneontology analysis identified candidate genes involved in proliferation, cell cycle and metabolism as genes to consider for further analysis. Quantitative RT-PCR (qRT-PCR) and standard western blot techniques were used to confirm regulation of selected up- and down-regulated genes at the mRNA and protein levels, respectively.

Results: Cell count analysis confirmed that LGD1069 greatly suppressed growth of HMEC cells, while LG100268 slightly suppressed HMEC growth. TUNEL analysis indicated that neither rexinoid treatment induced a significant amount of apoptosis in HMEC cells, indicating that the induction of growth suppression was not a result of apoptosis. A full list of genes up- and down-regulated by LGD100268 will be presented. Of those genes selected for further study, qRT-PCR analysis confirmed that LG100268 up-regulated stanniocalcin 1 (STC1), carbonic anhydrase IX (CA9), angiopoietin-like 4 (ANGPTL4), transglutaminase 2 (TGM2), and acyl-CoA synthetase long-chain family member 3 (ACSL3). Confirmed down-regulated genes at the mRNA level included cyclin B1 (CCNB1). Additional validation studies are ongoing. These up- and down-regulated genes may be useful targets for chemopreventive drug development.

Conclusions: These experiments identified a list of biomarkers that are regulated by LG100268. Such rexinoid-regulated molecules represent possible targets for breast cancer preventative therapy, alone or in combination with rexinoids. Support: NCI R01 CA78480 (PHB and IPU), and NIH/NCI T32 CA90221 (JMR).

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A32.

Abstract B32: Racial/ethnic disparities and trends in screening for colorectal cancer among Medicare beneficiaries with cancer and those without cancer in SEER areas, 1992-2002

White, A. L., Vernon, S. W., Franzini, L., Du, X. L. — Thu, 07 Jan 2010 13:54:15 PST

Background: Moderate racial differences have been documented for individuals screened for colorectal cancer (CRC). However, little is known about whether these disparities have changed over time. This study aimed to examine the trends in screening disparities by race from 1992 to 2002.

Methods: The study population consisted of two cohorts: 50,186 Medicare beneficiaries diagnosed with CRC between 1992 and 2002 and 62,917 Medicare beneficiaries without cancer during the same time period. Both cohorts of subjects were 67 to 89 years of age and resided in 16 Surveillance, Epidemiology and End Results (SEER) regions of the United States. Screening procedures conducted between 6 months and 3 years prior to the date of diagnosis for CRC patients and prior to the index date for persons without cancer were identified from Medicare claims. Age-gender-adjusted percentages of persons receiving the fecal occult blood test (FOBT), sigmoidoscopy (SIG), or colonoscopy (COL) by year and race/ethnicity were reported. Multivariable logistic regression analysis was used to assess the relationship between race/ethnicity and the odds of receiving CRC screening over time.

Results: Overall screening rates were similar between patients with colorectal cancer and those without cancer for FOBT (19.8% vs. 23.1%), SIG (6.2% vs. 5.2%) and COL (1.8% vs. 1.7%). Furthermore, there were higher screening rates in 2002 than in 1992 for all screening modalities within both groups of subjects. In the cohort of patients with CRC, there were no significant racial disparities in receiving CRC screening prior to the date of diagnosis. For example, the odds ratio for receiving FOBT was 1.07 (95%CI: 0.98–1.17) for Blacks, 0.94 (95%CI: 0.82–1.08) for Asians and 0.83 (95%CI: 0.67–1.01) for Hispanics compared to Whites with CRC in 2000–2002. However, among those without cancer, there were racial/ethnic differences in the use of FOBT and SIG. From 1992 to 1995, Blacks and Hispanics were less likely than Whites to receive FOBT (OR=0.75, 95% CI: 0.65–0.87; OR=0.50, 95% CI: 0.34–0.72, respectively) but the racial gaps in screening slightly widened from 2000 to 2002 (OR=0.79, 95% CI: 0.72–0.85; OR=0.67, 95% CI: 0.54–0.75, respectively). In addition, Blacks and Hispanics were less likely than Whites to receive SIG from 1992 to 1995 (OR=0.75, 95% CI: 0.57–0.98; OR=0.29, 95% CI: 0.12–0.71, respectively), but the disparities also widened from 2000 to 2002 (OR=0.79, 95% CI: 0.68–0.93; OR=0.50, 95% CI: 0.35–0.72, respectively).

Conclusions: Among Medicare beneficiaries without cancer, screening rates for FOBT and SIG differed between Blacks and Whites, and Hispanics and Whites. These disparities decreased in the later years, but were not eliminated. For patients with colorectal cancer, there were no statistically significant differences in screening prior to the diagnosis between racial groups. Future studies should incorporate information on physician recommendations and language/cultural barriers in these and younger populations.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B32.

Abstract A33: Expression of markers of inflammation and angiogenesis in preneoplastic lesions and colon cancer progression

Thu, 07 Jan 2010 13:54:03 PST

Colorectal cancer (CRC) was the first solid tumor to be successfully targeted with anti-angiogenic therapy in the clinic. Tumor angiogenesis is critical for cancer progression in that it permits expansion of the tumor mass and fosters malignant dissemination. Angiogenesis is a multistep process involving endothelial cells as well as numerous stromal components within the tumor microenvironment that also represent potential therapeutic targets. Inflammation dependent-angiogenesis is increasingly recognised as a central force in tumor growth and progression, while use of anti-inflammatory drugs has been found to reduce incidence of CRC carcinoma potentially through repression of tumor angiogenesis. We investigated the link between inflammatory angiogenesis and colorectal cancer in archival tissues across a range of pathologies that represent diverse steps in the progression of CRC: 16 cases of ulcerative colitis (URC), 16 adenocarcinomas developed from pre-existing tubular or tubulo-villous adenomas, 33 tubular or tubulo-villous adenomas with low grade dysplasia, and 33 infiltrating adenocarcinomas. Immunohistochemical analysis was performed with antibodies targeting markers of endothelial cells (CD31), macrophages (CD-68), neutrophils (CD15), growth factors (HGF), cytokines (IL-6) and up-stream receptors (TLR4). Epithelial, interstitial and endothelial/vascular compartments were chosen for analysis. Staining for (HGF) showed a rapid drop from healthy to pathological conditions, but did not show changes in staining intensity with the different stages of CRC progression. In contrast, the markers for vascularization (CD31) inflammatory cells (CD68, CD15) and inflammation (IL-6 and TLR4) increased in staining intensity as a function of tumor progression as determined by histopathology. IL-6 and TLR4 staining appear to correlate with event-free survival. These data suggest that inflammation increases along with tumor progression, and staining for CD68, CD15, IL-6, and CD31 appear to act as early tumor markers that increase with tumor progression, from precursor entities to invasive CRC. Increased TLR-4 and IL-6 was also found in tumor tissues derived from animals lacking Tir-8, an interleukin-1/Toll-like receptor family member highly expressed in the intestinal mucosa, in the azoxymethane and dextran sulfate sodium salt (DSS) model of CRC, confirming that these markers of inflammatory events are associated with colorectal tumor progression.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A33.

Abstract B33: Reducing the ethnic/minority cancer burden in communities in S.E. Michigan utilizing a community-based participatory process

Thu, 07 Jan 2010 13:54:15 PST

Purpose: We reviewed the impact of a community based participatory process (CBPP) addressing cancer education, prevention, and screening in five major ethnic/minority populations in Southeastern Michigan to determine their impact on personal health related decisions.

Materials and Methods: From 2003 to 2009, 2,988 community members participated in CBPP conducted by Beaumont Cancer Institute in collaboration with the Arab American and Chaldean Council, Michigan Association of Physicians from India, North American Indian Association, American Indian Health and Family Services, Mexican Consulate, Multicultural La Famila, National Cancer Institute, and American Cancer Society. The study population consisted of 1,253 (42%) individuals completing a post-cancer forum survey and/or obtaining some type of cancer screenings: 747 (59.6%) from African American, 425 (33.9%) from Arab American/Chaldean, 14 (1.1%) from Native American, 35 (2.8%) from South East Asian and 32 (2.6%) from Hispanic/Latino communities. Data were collected on behavioral intent and knowledge including: (1) forum content, (2) participants' cancer screening history, (3) symposium logistics (4) educational materials and (5) participation in subsequent cancer screening tests.

Results: After attending at least one cancer forum, 426 (34%) of 1,253 respondents (14.3 % of all attendees) underwent some type of cancer screening: 146 women (11.7%) underwent a screening mammogram, 94 (7.5%) a pap smear and 97 (7.7%) men underwent a screening PSA. A total of 89 (7.1%) had other forms of cancer screenings.

Conclusions: Results from this study suggest that CBPP's around a perceived and/or serious disease negatively affecting a target population can positively impact their personal health related decisions.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B33.

Abstract A34: Nonmelanoma skin cancer and the risk of second primary cancers: A systematic review

Wheless, L., Black, J., Alberg, A. J. — Thu, 07 Jan 2010 13:54:03 PST

Context: Based on empirical evidence, the hypothesis has been set forth that a personal history of non-melanoma skin cancer (NMSC) may be a marker of a high cancer-risk phenotype. Others hypothesize that NMSC may be a marker of high vitamin D synthesis and therefore inversely associated with risk of other malignancies.

Objective: To reconcile these divergent views, we carried out a systematic review to determine the overall association between nonmelanoma skin cancer and subsequent risk of other cancers.

Data Sources: PubMed and Ovid/MEDLINE databases were searched through March 2009. The formal search was supplemented by hand searches.

Study selection: Articles were included if sufficient information was presented to estimate the risk of developing other cancers following NMSC.

Data extraction: Articles were reviewed and data abstracted independently in duplicate with disagreements decided by consensus.

Results: Of the 21 included articles, 15 presented on NMSC in relation to risk of all other cancers combined. NMSC was associated with a 17% increased future risk of another malignancy (summary random-effects RR (SRR) 1.17, 95% confidence interval (CI) 1.11–1.22). This association held true for both squamous cell carcinoma (SRR 1.21, 95% CI 1.14–1.28) and basal cell carcinoma (SRR 1.15, 95% CI 1.07–1.24), and both men (SRR 1.15, 95% CI 1.09–1.20) and women (SRR 1.10, 95% CI 1.04–1.15).

Conclusions: Strong, consistent evidence indicates that a personal history of NMSC is associated with an increased risk of developing other malignancies. For reasons that are presently unknown, nonmelanoma skin cancer may be a marker of a high cancer-risk phenotype.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A34.

Abstract B34: An internet-delivered video intervention improves skin cancer detection behavior in melanoma patients

Loescher, L. J., Harris, R. B., Hibler, E., Hiscox, H., Quale, L. — Thu, 07 Jan 2010 13:54:16 PST

Introduction: Melanoma patients are at high risk of recurrence or additional primary lesions. Although early detection may prolong melanoma survival, few patients report engaging in early detection behaviors. Little is known about the types of interventions, including video, that affect skin cancer risk reduction behavior in this population. We found no studies of Internet-delivered video to facilitate skin cancer early detection behavior change. The purpose of this study was to: (1) develop and test a video intervention for skin cancer early detection; specifically to measure changes in self-reported melanoma awareness, melanoma attitudes and beliefs, and thorough skin self-examination (TSSE); (2) assess the feasibility of delivering and testing the intervention via the Internet.

Methods: Using concepts from social cognitive theory as a foundation, a team of researchers and media specialists developed a 13 minute evidence-based video, which addresses the seriousness of skin cancer, includes testimonials from patients and demonstrates TSSE. A technology specialist adapted an existing survey for the Internet to measure the main variables and created a study Website. To measure knowledge, participants answered ten items about warning signs of melanoma; possible scores ranged from 0 to 10. Skin cancer attitudes and beliefs (seriousness, self-efficacy, perceived risk) were measured by two 6-item scales that had acceptable internal consistency estimates (Cronbach' alpha = 0.70; 0.79). The TSSE measure was Weinstock' method to query how often during the previous two months participants examined seven specific parts of the body. We recruited adult patients with melanoma from a skin cancer specialty clinic. Shortly after enrollment, participants received an encrypted email with unique login information to access the pre-intervention survey. After completing the survey, participants could access the link to view the video. Three months later, they completed an identical post-intervention survey on the Internet. Data were stored in the Microsoft SQL server.

Results: 41 of 85 participants (mean age 61 years, 58% men, 42% women) completed both surveys. The video intervention significantly improved melanoma awareness (p=0.002) and self-reported TSSE performance (p=0.007), but did not change attitudes or beliefs. Contributing to attrition (failure to complete the second survey) were several issues related to use of the Internet; e.g. opening the video and surveys, nonfunctional email addresses. Characteristics of participants who completed the first survey and did not complete the second survey were similar, the only difference was that significantly more noncompleters had higher education levels.

Conclusion: Internet delivery of a video intervention is effective for short-term improvement of skin cancer knowledge and TSSE. Attitudes and beliefs about skin cancer remain stable. Using the Internet to deliver and test an intervention presents some challenges that merit careful consideration for future research.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B34.

Abstract A35: Chemoprevention of colon carcinogenesis in F344 rats by Se,Se'-1,4-phenylenebis(1,2-ethanediyl)bis-isoselenourea (PBISe) a novel analog of PBIT, an iNOS inhibitor

Thu, 07 Jan 2010 13:54:03 PST

Inducible nitric oxide synthase (iNOS) is potential target for inflammation and cancer. Previously, we have shown that S,S'-1,4-Phenylenebis(1,2-ethanediyl)bisisothiourea (PBIT) inhibit colon carcinogenesis induced by azoxymethane (AOM). Although, colon cancer inhibitory efficacy of PBIT has been significant, selective iNOS inhibitors do not completely abrogate NO production due to the exogenous bioavailability and NO generation by eNOS in tumor tissues. To create an iNOS selective and multi-targeted molecule, we have developed a novel isosteric analogue of PBIT, namely PBISe in which sulfur was replaced with selenium. We examined the chemopreventive efficacy of PBISe on AOM-induced rat colon carcinogenesis model using aberrant crypt foci (ACF) as end point. At seven weeks of age, rats (12/group) were fed the control diet (AIN 76A) and colonic ACF were induced by AOM. Three days after second AOM treatment, rats were fed the diets containing 0, 10 and 20 ppm of PBI-Se and continued on the respective diets for 8 weeks before ACF were evaluated histopathologically. Furthermore, PBISe (0–12 µM) and PBIT (0 – 100 µM) were studied for the markers of growth inhibition and induction of apoptosis in the human colon cancer CaCo2 cell line. In addition, inhibitory effect of PBISe and PBIT on proinflammatory signaling molecules iNOS, IL-8 and IL-6 were studied by RT-PCR. Results suggest that dietary administration of 10 and 20ppm of PBISe significantly suppressed AOM-induced total colonic ACF formation (32 – 41%, p< 0.001), and multi crypt (4 or more) aberrant foci (29 – 47%, p< 0.001) respectively. Dietary PBISe suppressed AOM-induced colonic ACF in a dose-dependent manner and it required less than half the dose of PBIT to inhibit total ACFs in rats. Both PBIT and PBISe in CaCo2 cells induced dose-dependent apoptosis. PBIT and PBISe treatment on CaCo2 cells showed significant decrease in cell cycle protein cyclin D1 (~70%, p<0.0001) and iNOS (~99%, p<0.0001). Also, treatment with PBIT (30 and 60 M) significantly decreased cytokine induced IL-6 at both the doses whereas PBISe had no such effect. PBIT significantly attenuated the LPS-induced IL-6 and IL-8 production in a dose dependent manner. Whereas, PBISe significantly increased IL-8 and attenuated IL-6 production in CaCo2 cells suggesting differential modulatory effects on immune cells/inflammatory pathways. Incorporation of selenium into the structure of PBIT has provided the agent with additional novel cytotoxic and immunologic properties. Results from in vitro and in vivo bioassay clearly suggest that PBI-Se could be further developed for prevention and treatment of colon cancer.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A35.

Abstract A36: Bracken fern carcinogen causes cancer in humans

Shahin, M. — Thu, 07 Jan 2010 13:54:03 PST

Bracken fern (genus Pteridium) is the only plant known to cause cancer naturally in animals. In addition to the well recognised syndromes of thiamine deficiency, acute haemorrhage associated with myeloid aplasia and blindness due to retinal degeneration, it causes neoplasia of urinary bladder and in some circumstances oesophagus origin. In addition, it has been shown to cause neoplasia in a wide range of tissues in many experimental species. The major carcinogen has been shown to be ptaquiloside (PT), a norsesquiterpene glucoside that can be present in bracken in extraordinary concentrations, up to 13000 ppm. The highest concentrations were found in the crosiers and young fronds. The mutagenicity, clastogenicity, tetratogenicity and carcinogenicity of PT have been convincingly demonstrated. Under alkaline conditions the loss of the glucose give rise to the formation of a dienone intermediate which possess a highly reactive cyclopropyl ring capable of reacting with cellular macromolecules. Pt has been shown to alkylate DNA at N3 of adenines in the minor groove, preferentially in 5'-TAG and 3'-A in 5'-AA-3' sequences. It also alkylates N7 guanines in the major groove occurring in 5'-TG sequences. It is believed that these alkylation lead to mismatch repair and subsequent mutations in particular proto-oncogene. Recently a rat model of carcinogenesis has been established using intravenously administrated PT. Some epidemiological evidence has indicated higher risk of cancer in people who consume bracken fern crosiers, people who consume milk of cows feeding on bracken and those live in bracken-infested areas. PT has been found in the milk of cows fed on bracken fern experimentally and the milk of bracken fed cows has been shown to cancer in rats. PT carcinogenesis presents an excellent model of environmental carcinogenesis. More recently it has been found that immunosuppressive effects of bracken fern (P. aquilinum) and that many of the functions that were modulated could contribute to the increased risk of cancer formation in exposed hosts.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A36.

Abstract A37: Differential response of LH and hCG on ovarian granulosa cells

Gupta, C., Chhabra, Y., Chapekar, T., Sinha, S., Luthra, K. — Thu, 07 Jan 2010 13:54:03 PST

LH hyperstimulation has been linked to conditions like PCOD and granulosa cell tumor. Chapekar had established a model of ovarian tumorigenesis by bilateral ovariectomy and splenic transplantation of ovaries, resulting in sustained LH levels because of absence of feedback inhibition. An in vitro model of the same phenomenon has resulted in goat ovarian granulosa cell line after exposure of primary granulosa cells to LH.

In this study, we have exposed primary ovarian granulosa cells to either hCG or LH in a sustained manner (4 weeks). We observed a marked difference in the morphology and growth pattern between the LH treated, hCG treated and untreated cells. LH treated cells were transparent, spindle shaped with elongated cell extensions. hCG treated cells were distinctly polygonal with shorter cell extensions, while untreated cells were smaller with fewer extensions and lesser in number as compared to the hormone treated cells. Functional characterization of the granulosa cells was done by estimation of progesterone in supernatant by ELISA. Levels of progesterone were similar in all three subsets in primary culture. The untreated and hCG exposed cells showed markedly reduced cell proliferation after the fourth week of exposure while LH treated cells were proliferating rapidly even after 4 weeks. There were marked differences in downstream signaling molecule cAMP after short term (5 days) and long term stimulation (two weeks) with LH and hCG. Intacellular cAMP was assessed by ELISA. On prolonged exposure to LH and hCG, level of cAMP was significantly higher in hCG treated cultures as compared to LH treated cultures. Elevated cAMP levels on hCG stimulation is known to promote apoptosis in cells.

This in vitro model system is suitable to study the effect of sustained hormonal stimulation on granulosa cells and can help in understanding the role of LH and hCG in etiology and pathogenesis of granulosa cell tumor which constitutes 1–2% of ovarian tumors.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A37.

Abstract B37: Genetic screening of HNPCC

Koinuma, N., Ito, M. — Thu, 07 Jan 2010 13:54:16 PST

Background and Objectives: Genetic testing and counseling for the patients with HNPCC (hereditary nonpolyposis colorectal cancer) are changing the cancer prevention strategies. However, the clinical evidence is still insufficient to make screening policy for at-risk carriers. In our study, while clarifying the economic effects/merits of genetic testing to HNPCC, the most appropriate age to start the screening from the viewpoint of health economics is presumed.

Materials and Methods: We developed systems model of colon cancer treatment along with Markov model, after sorting complicated clinical course of treatment by type. In the model, we presumed that the close relatives of the patient with HNPCC have genetic screening and continue undergoing the colonoscopic examination once a year afterward. We incorporated patients' data such as the cumulative morbidity of HNPCC, accumulated on the study groups of Japan into the systems model. When delaying cancer death by the intervention of genetic screening, the differences of the increment of the labor productivity of the prolonged period and that of the expense spent for the prevention and treatment is computed as an economic effect of cancer prevention.

Results and Discussion: The expense of genetic screening and endoscopy were $612 and $1,020 respectively. The stage distribution at the detection of colon cancer was as follows; I 36.8%, II 31.1%, III 19.2% and IV 12.9%. The utility value was assumed to be 0.8 in cost-utility analysis. In case of the male relative of the patient with HNPCC, the cost-benefit differences of genetic testing became large, if he would have genetic screening in his twenties. Hence, it became clear that genetic screening in younger age would have not a little meaning from cancer-economic point of view. Supposing he continued the examination in diagnostic phase in case of positive male, five-year survival rate after colon cancer treatment was as good as younger age when he underwent the genetic testing. In case of female, the rate of recovery is as good as younger age as well, but the cost-benefit differences became its maximum at her thirties rather twenties.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B37.

Abstract A38: Is the mycotoxin zearalenone bioactivated to genotoxic metabolites? In vitro evidence for mercapturic acid formation from catechol metabolites

Hildebrand, A., Pfeiffer, E., Metzler, M. — Thu, 07 Jan 2010 13:54:03 PST

The Fusarium toxin zearalenone (ZEN) is a frequent contaminant of corn and other grains world-wide and known for its high estrogenic activity. In a NTP carcinogenicity study, ZEN was found to increase the incidence of hepatocellular adenomas in female mice and of pituitary adenomas in both female and male mice. The mechanism of ZEN tumorigenicity is unknown to date and may be related to the hormonal activity. However, the recent disclosure of a novel pathway in the metabolism of ZEN opens up another possibility: ZEN was found to readily undergo aromatic hydroxylation when incubated with hepatic microsomes from humans and various other mammalian species, and two catechol metabolites were unequivocally identified in our laboratory (Pfeiffer et al., Mol. Nutr. Food Res. 53, 1123–1133, 2009). Thus, the phase I metabolism of ZEN resembles that of the steroidal estrogens 17β-estradiol (E2) and estrone (E1), which also form catechol metabolites. There is increasing evidence that these catechol metabolites contribute to the well-established carcinogenicity of E2 and E1 by acting as genotoxins after further activation to quinones (Cavalieri and Rogan, Ann. N. Y. Acad. Sci. 1089, 286–301, 2006; Bolton and Thatcher, Chem. Rev. Toxicol. 21, 93–101, 2008). A similar mechanism is conceivable for the carcinogenicity of ZEN. In order to obtain evidence for the formation of reactive quinone metabolites from ZEN, it was the aim of the present study to trap such quinones as mercapturic acids in microsomal incubations fortified with N-acetylcysteine (NAC).

Incubations (0.4 mL of 0.1 M phosphate buffer pH 7.4) containing human hepatic microsomes (0.4 mg protein), ZEN (0.1 mM) and a NADPH-generating system were conducted for 10 min at 37°C for the formation of catechol metabolites. 0.1 mL of a 40 mM NAC solution in water was then added and incubation continued for another 30 min. Thereafter, 0.5 mL of 0.7 M glycine/HCl buffer pH 1.2 was added and the NAC adducts were extracted with 2 x 0.5 mL ethyl acetate. Analysis of the extract by LC-MS/MS revealed the presence of at least two NAC adducts, which were identified as the N-acetylcysteinyl derivatives of one of the catechol metabolites of ZEN and of its microsomal reductive metabolite alpha-zearalenol by comparison with authentic synthetic standards.

This is the first report to show that reactive quinone metabolites of ZEN are formed in vitro. The toxicological sequelae of this pathway and its in vivo relevance should now be studied.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A38.

Abstract A39: In vitro mechanisms of cadmium-induced apoptosis in human liver carcinoma (HEPG2) cells

Skipper, A. C., Tchounwou, P. B., Yedjou, C. — Thu, 07 Jan 2010 13:54:03 PST

Cadmium is a heavy metal that has been shown to manifest its toxicity in humans and animals. Many documented in vitro studies have shown that cadmium produces various genotoxic effects such as DNA damage and chromosomal aberrations. Diseases like autoimmune thyroidism are thought to be caused, in large part, by overexposure to cadmium. Although there have been numerous studies examining the effects of cadmium in animal models and a few case studies involving communities where cadmium contamination has occurred, the mechanisms of the carcinogenic activity of cadmium is not clearly defined. Therefore, the purpose of this study was to elucidate some of the molecular mechanisms that are involved in cadmium-induced toxicity in human liver carcinoma (HepG₂) cells. To achieve this goal, we performed the MTT assay to measure cell viability. Annexin V assay and DNA fragmentation analysis were performed for early and late apoptosis, respectively. The result of MTT assay indicated that cadmium induces toxicity to HepG₂ cells in a dose-dependent manner, showing a 24 h-LD50 of 3.6 µg/mL cadmium chloride. Similarly, a strong dose-response relationship (p < 0.05) was obtained in connection with cadmium chloride-induced apoptosis. Cadmium chloride-induced apoptosis was characterized by a significant increase in the percentages of annexin-V positive cells, as well by the occurrence of nucleosomal DNA fragmentation. In summary, this study indicated cadmium chloride is highly cytotoxic to HepG₂ cells. This cytotoxic effect may be mediated at least in part through phosphatidylserine externalization and occurrence of nucleosomal DNA fragmentation.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A39.

Abstract B39: Prostaglandin E2 induces human enhancer of filamentation 1 to promote the cell motility of colorectal carcinoma cells

Xia, D., Wang, D., Menter, D. G., DuBois, R. N. — Thu, 07 Jan 2010 13:54:16 PST

PGE2 promotes cell motility during colorectal carcinogenesis. The mechanism by which PGE2 signaling regulates cell motility is not completely understood. Here, we demonstrated that PGE2 treatment induces HEF1 expression that links with cell motility in colorectal cancer cells. PGE2 rapidly stimulated HEF1 expression in colorectal cancer cells. Both PGE2 treatment and HEF1 overexpression activated Rac 1 and resulted in similar effects on cell spreading. Moreover, knockdown of HEF1 using shRNA suppressed PGE2-driven cell spreading. PKA activator forskolin induced HEF1 expression and cell spreading in a similar manner as PGE2. Inhibition of PKA activity by H-89 attenuated HEF1 expression induced by PGE2. Furthermore, PKA knockdown by siRNA blocked the HEF1 expression and cell spreading induced by PGE2. These data suggest that PGE2 induces HEF1 expression to promote cell motility through a PKA-involved pathway.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B39.

Abstract A40: Exposure of children and pet dogs to chemicals in lawn care products

Thu, 07 Jan 2010 13:54:03 PST

Exposure to lawn herbicides and pesticides has been associated with increased risk for invasive urinary bladder cancer in pet dogs. There is concern of potential risks for humans as well. Among many steps to further investigate this finding, two were addressed here. The purpose of this work was to determine: (1) length of time for potential exposure to chemicals after lawn treatment, i.e. residence time of chemicals on grass, and (2) lawn chemical concentrations in the urine of pet dogs and children living in households that used commercial lawn products. Marker chemicals commonly used in lawn products were selected to track potential exposures. Methods: The work included 2 parts. 1. Residence chemical times were studied in experimental grass plots to define methods and sampling times for the subsequent work. Briefly, a product containing 0.169% 2,4-dichlorophenoxyacetic acid (2,4-D), 0.045% 4-chloro-2-methylphenoxypropionic acid (MCPP), and 0.015% Dicamba was applied by calibrated sprayer at manufacturer recommended amounts under different lawn conditions (green, dry brown, wet, recently mowed grass). Chemicals in the dislodgeable residue were measured by LC-MS (0.17, 24, 48, 72 hrs post treatment). 2. A household study was conducted in which chemical (2,4-D, MCPP) residence times and chemical concentrations in urine of children and dogs were determined at 0, 24, and 48 hrs post lawn treatment. Questionnaires regarding lawn exposure for dogs and children were completed for treated and for untreated (control) households. Results: In the experimental grass plot study, minimal amounts of 2,4-D, MCPP, and dicamba were still detected at 48 hours post chemical application to green lawns, although chemical residence time was prolonged (P < 0.05) on dry brown grass. In the household study, chemical concentrations were more than 5 fold higher in some lawns, and chemical residence times were considerably longer (up to 196 µg/m² of 2,4-D at 48 hrs) than for the experimental grass plot study. No chemicals were detected in the urine of children, although children in this study spent little time on the lawn. Chemicals (0.69 – 6.12 mg/g creatinine 2,4-D, 0.20 – 0.68 mg/g creatinine MCPP) were detected in the urine of dogs in 4 of 9 treated households. No chemicals were detected in the urine of dogs in 5 control households. Conclusions: The findings of much higher concentrations and longer residence times (>48 hrs) of chemicals on commercially treated lawns compared to experimental grass plots treated with recommended amounts of herbicide suggest that excessive amounts of chemicals are applied in some commercial settings, thun increasing exposure potential. Detection of chemicals in the urine of dogs in 4 of 9 treated households confirms that chemical uptake and internalization occurs, and that a clear exposure risk exists for pet animals. Further study is needed to assess the exposure risk to humans.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A40.

Abstract B40: Suppression of Stat3 inhibits the invasive potential of malignant squamous cell carcinoma by interfering with the HGF/cmet/Stat3 signaling pathway

Syed, Z., Yin, W., Gill, J., Hughes, K., Clifford, J. L. — Thu, 07 Jan 2010 13:54:16 PST

Cancer cell invasion and induction of the metastatic cascade are often the consequence of deregulated cell adhesion and migration. There is substantial evidence for the involvement of Stat3 in cell motility, migration, and invasion under normal and pathological situations. Stat3 activation is required for induction of genes encoding MMP-1, MMP-2, and MMP-9, key components of tumor invasion. Through binding to its receptor, cmet, hepatocyte growth factor (HGF) can regulate cell survival, growth, migration, and angiogenesis. cmet is often constitutively active in human tumors and HGF/cmet signaling is at least partially mediated by Stat3. Overall, these observations suggest that positive feedback signals in the HGF/cmet/Stat3 signaling pathway contribute to tumorigenesis.

To explore the role of Stat3 in skin cell malignancy in a human cell culture model, our lab has overexpressed a dominant negative form of Stat3β in the tumorigenic SCC cell line, SRB12-p9. We established SRB12-p9 cell clones expressing FLAG-tagged Stat3β-Y705F (S3DN). Suppression of Stat3 activity impaired the ability of these cells to scatter upon stimulation with HGF, diminished their capacity to invade, and enhanced adhesion in vitro. S3DN cells also showed suppressed HGF-induced activation of cmet, as revealed by a phospho-specific cmet antibody. We next assessed the role of Stat3 in tumor invasion using in vivo mouse tumorigenicity experiments. When injected subcutaneously into immune-deficient mice, S3DN cells produced tumors that were less locally invasive, though WT tumors were more differentiated as indicated by K10 immunostaining. Upon further examination of these tumors, we found that those arising from WT cells had more intense membrane staining for total cmet and phospho-cmet than S3DN cells, indicating stronger cmet activity in these tumors. This pattern of cmet staining correlated with increased phospho-Stat3 membrane staining in the WT tumors. Western blotting revealed a decrease in MMP-2, MMP-9, and cmet expression in the S3DN cells. These results are consistent with those from the in vitro experiments. Finally, we show that S3DN may interfere with Stat3/cmet interaction, as evidenced by co-immunoprecipitation experiments, preventing the activation of cmet at the cell membrane. Ongoing studies will further address the effect of S3DN expression on cmet signaling and the effect this has on the HGF/c-met/Stat3 signaling loop and tumor cell invasion.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B40.

Abstract A41: Regulation of Nrf2-dependent gene expression in aging

Ma, Q., Han, Z., Yu, R. — Thu, 07 Jan 2010 13:54:04 PST

Nrf2 is a transcription factor which controls induction of antioxidant and detoxification enzymes, and, therefore, plays an essential role in protection against chemical carcinogens. Here, we reported that expression of Nrf2 and its dependent genes was affected by age and became compromised in aged mouse livers. Detail analysis revealed that age-dependent Nrf2 expression was regulated primarily at transcriptional level. Accordingly, we cloned and characterized the promoter region of mouse Nrf2 gene. We identified multiple Sp1 binding sites and confirmed their binding activity by gel-shift and chromatin immunoprecipitation assay. We also showed that the identified Sp1 sites were functional since knockdown of Sp1 expression impaired Nrf2 promoter activity as well as expression of Nrf2-dependent genes. We then compared Sp1 expression and its binding activity to Nrf2 promoter in young and aged mouse liver tissues. While no significant change in Sp1 expression was found, Sp1 binding activity was severely impaired in aged tissues. Given that Sp1-binding sites are GC rich elements, we analyzed their methylation status in Nrf2 promoter, and found that Sp1 sites were highly methylated in aged tissues. In support of the role of methylation, treatment of a mouse hepatoma cell line with demethylase inhibitors indeed reduced Sp1 binding to Nrf2 promoter. We also cloned and analyzed human Nrf2 promoter. Multiple Sp1 binding sites were identified and shown to be equally functional as in mouse Nrf2 promoter. Thus, we propose that age-dependent expression of Nrf2 and its downstream genes is regulated by methylation. A strategy that targets methylation would help to restore Nrf2-mediated protection against oxidative stress or chemical carcinogens in aged tissues.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A41.

Abstract B41: Inhibition of beta-arrestin2-CARMA3 signaling axis impairs lysophosphatidic acid-induced ovarian cancer migration and invasion

Sun, J., Cai, J., Feng, Y. — Thu, 07 Jan 2010 13:54:16 PST

Ovarian cancer is the fourth leading cause of cancer death among women in the United States. One of the biomarkers of ovarian cancer is lysophosphatidic acid (LPA). LPA is a type of G protein-coupled receptor ligand. It is strikingly elevated in 90% of ovarian cancer patients. Additionally, LPA receptors are aberrantly up-regulated in ovarian cancer patients. We have reported previously that a signaling axis consisting of beta-arrestin 2 and CARMA3 (CARD and MAGUK domain-containing protein 3) is indispensable in LPA-induced nuclear factor kappa B (NF-kappaB) activation in mouse embryonic fibroblast cells. NF-kappaB is an important transcription factor, which has been suggested to mediate LPA-induced ovarian cancer migration and invasion. However, it remains unknown whether the beta-arrestin2-CARMA3 signaling axis plays an important role in LPA-induced ovarian cancer cell migration and invasion. In the present study, using beta-arrestin 2 and CARMA3 shRNA, we knockdowned their protein expression levels in ovarian cancer cell lines. Consistent with previous reports, we found that down-regulation of beta-arrestin 2 and CARMA3 abolished LPA-induced IKK activity and NF-kappaB activation in ovarian cancer cells. In addition, in vitro transwell migration and matrigel invasion assays demonstrated that beta-arrestin 2 and CARMA3 shRNA significantly impaired LPA-induced ovarian cancer cell motility and invasiveness. Together, our results provide the evidence that β-arrestin 2 and CARMA3 serve as critical regulators in LPA-induced, NF-kappaB-mediated ovarian cancer migration and invasion. Therefore, we speculate that β-arrestin 2 and CARMA3 may represent attractive therapeutic targets for ovarian cancer and many other types of malignancies.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B41.

Abstract A42: Comparison between NO-ASA and NONO-ASA as safe anti-inflammatory, analgesic, antipyretic, antioxidant chemopreventive prodrugs

Chattopadhyay, M., Velazquez, C. A., Keefer, L. K., Kashfi, K. — Thu, 07 Jan 2010 13:54:04 PST

Introduction: Chronic inflammation is widely recognized as an underlying etiological factor in carcinogenesis; there is enough evidence to support the use of non-steroidal anti-inflammatory drugs (NSAIDs), and more importantly, their chemically-modified NO-releasing prodrugs (NO-NSAIDs) as promising chemopreventive agents. Metabolic activation of organic nitrate-containing NO-aspirins may lead to a cytotoxic "activated" linker (a quinone methide), raising safety concerns. Replacement of organic nitrates with N-diazeniumdiolates as a second-generation NONO-NSAIDs allowed us to conduct a head-to-head comparison between NCX-4016 (NO-aspirin), CVM-01 (NONO-aspirin), and aspirin as analgesic, anti-inflammatory, and anti-pyretic agents with no significant gastrointestinal toxicity.

Methods: a) Anti-inflammatory: paw edema induced by intraplantar injection of 100 µL of 1% carrageenan, paw volumes measured up to the tibiotarsal joint immediately prior to carrageenan injection and thereafter at 1hr intervals up to 6hrs. Drugs were administered orally 1 hr before carrageenan; b) Anti-pyretic: body core temperature was measured twice at 15 min intervals before administration of lipopolysaccaride (LPS, 50µg/kg, ip) to induce fever. Drugs administered 1hr before LPS; c) analgesic: the time-dependent analgesic effect of prodrugs was evaluated by carrageenan-induced hyperalgesia. Drugs were administered orally 2.5 hours after carrageenan; d) Anti-ulcerogenic: Rats fasted for 48h before drug administration. After 6 hrs animals were euthanized, stomachs removed, cut along the greater curvature, lightly rinsed with water, and observed (with magnifying lenses) to count the numbers and measure the lengths (in mm) of all hemorrhagic lesions ("gastric damage score") for each stomach. Tissue samples immediately frozen in liquid nitrogen for PGE2, SOD, and MDA determination.

Results: NCX-4016 and CVM-01 decreased the carrageenan-induced edema 1h after administration and maintained this anti-inflammatory effect throughout the experiment (up to 7h). Both compounds showed improved anti-inflammatory effect compared to aspirin 3–7h post administration. All test drugs (aspirin, NCX-4016, and CVM-01) were effective anti-pyretics, decreasing the body core temperature starting at 1h post-administration. At the end of the assay (5h) aspirin prodrugs showed slightly improved anti-pyretic effect compared to aspirin. Despite a drastic reduction of PGE2 levels induced by NCX-4016 and CVM-01 in stomach tissue, both prodrugs were devoid of gastric side effects (gastric index < 5) aspirin (GI=48). Lipid peroxidation induced by aspirin (MDA=57 nmol/mg protein) was higher than that observed by the prodrugs NCX-4016 (MDA= 9nmol/mg) and CVM-01 (13 nmol/mg), which resembled control tissue (MDA=12 nmol/mg). Superoxide dismutase (SOD): aspirin (SOD=12 U/mL), NCX-4016 (SOD=21 U/mL), CVM-01 (20 U/mL), control tissue (23 U/mL).

Conclusions: The N-diazeniumdiolate containing aspirin prodrug CVM-01 is as effective as NCX-4016 (an organic nitrate-containing aspirin prodrug) in anti-inflammatory, analgesic, and anti-pyretic assays in vivo, and it showed an equivalent safety profile in stomach. These results underscore the use of diazeniumdiolate-containing NSAIDs (NONO-NSAIDs) in future chemopreventive assays.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A42.

Abstract B42: Modulation of integrin-mediated cell adhesion by ADAM15 disintegrin-like domain

Lee, H. D., Park, M. Y., Jeon, O.-H., Kim, D.-S. — Thu, 07 Jan 2010 13:54:16 PST

Integrin-mediated cell adhesion on extracellular matrix works essentially on numerous physiological processes such as cell adhesion, migration and angiogenesis. As integrin β3 and integrin 5β1 are the representative receptors for cell adhesion and due to their important function in cancer biology, the antagonists targeting the integrins has been sought for long. Lately, the interactions between ADAM (A Disintegrin And Metalloprotenase) 15, the only member in ADAM family with Arg-Gly-Asp (RGD) motif, and the β3 and 5β1 intergins was observed. For that, we experimented on the cellular function of recombinant ADAM15-derived disintegrin-like domain containing Asp-Typ-Lys-Arg-Gly-Asp (rNWKRGD) in integrin-mediated cell adhesion. The binding affinity of HUVEC, COS-1, MCF-7 and MDAH 2274 cells to various extracellular matrix proteins were increased by the disintegrin-like domain in a dose-dependent manner, and the presence of inhibitory integrin 5β1 antibody thoroughly abrogated the rNWKRGD-stimulated binding. By mutagenic analysis, it was founded that RGD motif is essential for the binding. In comparison, saxatilin, RGD disintegrin from snake venom, inhibited binding of cells to ECM proteins. Through flow cytometric analysis, we confirmed that β1 integrin on the cell surface was activated by rNWKGRD. All these results indicated that the activation of integrin 5β1 mediates the rNWKRGD-stimulated cell adhesion. Therefore rNWKRGD could function as the potential activator of cell migration and proliferation. Although disintegrin is known as inhibitor of cell migration and proliferation, it is possible that ADAM15 disintegrin domain could have a regulatory role in integrin function such as angiogenesis and invasion of cancer cells. (This work was supported by the Korea Science and Engineering Foundation (KOSEF) grant funded by the Korea government (No. 2009-0081759), KIST grant, and the Brain Korea 21 (BK21).)

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B42.

Abstract A43: Effect of chemoradiation on oxidant-antioxidant profile and its correlation with therapeutic response in patients with carcinoma of posterior one third of tongue

Sharma, M., Sharma, A., Khan, R. — Thu, 07 Jan 2010 13:54:04 PST

Background and Objectives: Cancer of posterior one-third of tongue is seen in 0.43% of total world population. Squamous cell carcinoma of head and neck is the most common cancer encountered in India. Oxidative stress is potentially harmful to cells and ROS are involved in multistage carcinogenesis, in initiation and promotion. Moreover, the extent of ROS-induced oxidative damage can be exacerbated by decreased efficiency of antioxidant defense mechanisms. The correlation of therapeutic response on chemoradiation with the change in oxidant-antioxidant profile has not been studied till date. The aim of this study was to study the alterations in the circulating lipid peroxide, antioxidant components and the activities of defense enzymes in patients with cancer of posterior one-third of tongue and to monitor the variations in their levels before and after chemoradiation and to assess the relevance of these levels to therapeutic response.

Methods: Sixty newly diagnosed patients with cancer of posterior one-third of tongue (Stage III–IVa) and 60 healthy controls were enrolled in this study. The samples were collected: before the start of therapy; after the second course of chemotherapy; two weeks after the completion of teleradiation and after 1 year on follow-up. Single blood samples were taken from controls. Lipid peroxides, conjugated dienes, reduced glutathione (GSH), catalase (CAT) and glutathione-S-transferase (GST) were estimated using standard methods. Glutathione peroxidase (GPx) and superoxide dismutase (SOD) were assayed using commercially available kits from Randox, UK. Response to therapy was assessed during and after therapy and after one year of follow-up.

Results: The pre-treatment levels of plasma lipid peroxide were significantly elevated whilst significantly lowered levels of GSH, GPx, GST, SOD and CAT were observed in cancer patients, when compared to controls. After chemotherapy, the levels of lipid peroxidation showed a significant decline in complete responders, as compared with partial/non-responders; which became highly significant after completion of therapy. This fall remained significant after one year of completion of therapy during follow-up. The levels of GSH, GPx, SOD and CAT showed a mild increase (p<0.05), after chemotherapy in complete responders, as compared with partial/non-responders; which became highly significant after completion of therapy.

Conclusion: This important finding suggests that pre-treatment levels of antioxidant-oxidant parameters and the extent of their change during treatment can predict the therapeutic response to chemoradiation in patients with cancer of posterior one-third of tongue A larger patient cohort with a longer follow-up period for therapeutic response studies might yield more significant data on their probable use as predictors of chemoradiosensitivity of advanced tongue cancer.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A43.

Abstract B43: Role of angiogenic factors and extracellular matrix proteins in multiple myeloma

Sharma, A., Khan, R., Joshi, S., Sharma, M., Kumar, L. — Thu, 07 Jan 2010 13:54:16 PST

Background and Aim: Multiple myeloma (MM) is characterized by a clonal proliferation of abnormal plasma cells in bone marrow. Angiogenesis is required by tumor cells to survive, proliferate and metastasize but its role in hematologic malignancies is limited. Central to the angiogenic cascade are endothelial specific receptor tyrosine kinases (RTKs) and their respective ligands such as Angiopoietins and VEGF. Angiogenic factors are known to regulate matrix proteins in solid tumors. It may be possible that these factors function via up-regulation of ECM proteins such as integrins, laminins and plasminogen activator. Extracellular matrix (ECM) proteins are involved in invasion of myelomic cells to bone marrow microenvironment. The urokinase-type plasminogen activator (uPA) system and laminin are involved in cell migration, tissue remodeling, angiogenesis and cell adhesion. Angiopoietins (Ang) and their association with ECM proteins which may provide an alternative pathway in angiogenesis and myeloma growth have not been well studied in MM. Therefore, the aim of this study was to investigate the expression of angiogenic factors (Ang-1, Ang-2, and VEGF) along with ECM proteins (uPA, Laminin) at the circulatory as well as cellular level and their correlation with the pathogenesis of Multiple Myeloma.

Methods: Fifty patients of MM (Grade II: 33, Grade III: 17) and fifty healthy controls were enrolled. All the patients included were newly diagnosed and staged according to International system of staging, rely on β2 microglobulin levels. The circulatory levels of angiogenic factors (Ang-1, Ang-2, and VEGF) and Laminin were measured by commercially available ELISA kits. uPA activity was measured by activity assay kit. The mRNA expression of angiogenic factors and ECM proteins in the Peripheral blood mononuclear cells (PBMC) were further detected by RT-PCR. The data were analyzed statistically.

Results: The statistical significant (p < 0.001) increase was observed in Ang-2, VEGF, uPA and laminin levels and found to be significantly correlated with each other, in MM patients. Increased mRNA expression for VEGF, Ang-2, uPA and laminin has also been observed in the isolated PBMC by RT-PCR. No significant change was found for Ang-1 levels at the circulatory and cellular level.

Conclusion: Elevated expression of Ang-2 and VEGF suggest their involvement in the process of angiogenesis in MM as they both are involved in vessel sprouting and neovessel formation. Increased expression of laminin and plasminogen activator might facilitate the myeloma plasma cells to interact with the bone marrow microenvironment and influence important biological events such as bone matrix degradation, plasma cell invasion and homing. Hence this study suggests that Angiopoietins, VEGF signaling as well as ECM proteins might contribute to the complicated and unregulated process of angiogenesis in MM. Such a study might facilitate the therapies to prevent MM by targeting not only the tumor cell but also the bone marrow microenvironment.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B43.

Abstract A44: Role of HLA-G 14bp insertion deletion in cancer susceptibility and progression

Thu, 07 Jan 2010 13:54:04 PST

Human leukocyte antigen -G (HLA-G) is an immunosuppressive protein with multiple functions. The 14bp insertion / deletion in exon 8 of HLA-G gene have been shown to play an important role in HLA-G mRNA stability as well as expression level; and can be correlated with its immunosuppressive function. The role of HLA-G in various cancers has already been demonstrated. Cancerous cells start expressing HLA-G which in turn provides a shield for various immune responses. In the present study we have tested the possibility of the role of 14bp insertion / deletion polymorphism of HLA-G in cancer progression and susceptibility. We have genotyped 59 cancer samples (26 benign and 33 malignant) and 79 matched controls for 14bp polymorphism of HLA-G. Data showed increase of +14bp/–14bp and –14bp/–14bp genotype with both benign and malignant cancer. We observed significantly higher frequency of +14bp/+14bp genotype in control (p=0.01). This is consistent with both benign and malignant tumors as well as cancer types showing possibility of protective effect of +14bp/+14bp genotype in various cancers. However, further studies will be required with large sample size to test this hypothesis. The +14bp/–14bp and –14bp/–14bp genotypes have already been showed to be associated with higher expression of HLA-G and its mRNA stability and might be providing favorable micro-environment for cancer progression. There is no published work till date showing the role of HLA-G 14bp polymorphism in various cancers. These preliminary data showed that HLA-G 14-bp genotypes might be playing an important role in pathogenesis of various cancers.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A44.

Abstract A45: Kupffer cell and EtOH DNA synthesis

Owumi, S. E. — Thu, 07 Jan 2010 13:54:04 PST

The Kupffer cells (KC) are the resident hepatic macrophage located in the sinusoidal space of the liver. KC plays an important role in hepatic homeostasis and in the response of the liver to xenobiotics. It phagocytizes foreign bodies, old red blood cell and interacts with endotoxin resulting in its activation. Activated KC releases cytokines such as tumor necrosis factor alpha (TNF-) and reactive oxygen species (ROS) like superoxide. TNF- and superoxide have been implicated in signalling transduction involved in cell growth, gene expression and apoptosis. Ethanol (EtOH) consumption has been causally linked to the etiology of primary hepatocellular cancer (HCC), although EtOH is not a known carcinogen. One such mechanism of KC activation is via EtOH-induced endotoxemia, which leads to an increase in cytokine and ROS production by the KC, consequently impacting on and potentially induces hepatocyte growth. Here we propose that depletion of Kupffer cells will attenuate the effect of EtOH induced endotoxemia, decreasing hepatocyte deoxyribonucleic acid (DNA) synthesis required for cell growth.

Rate of hepatocyte DNA synthesis was examined as a marker of cell growth in C57BL6 mice depleted of KC (KC–) with clodronate-liposome and in KC competent mice (KC+). Both groups of mice were fed an isocaloric EtOH-liquid diet (3%w/v EtOH). Control mice were fed a liquid diet without EtOH for 1 week. DNA synthesis was assessed by 5-bromo-2'-deoxyuridine (BrdU) incorporation into hepatocytes undergoing replicative DNA synthesis by BrdU-immunohistochemistry. Apoptotic bodies' formation was examined by the TUNEL assay and Extracellular Regulated Kinases (ERK 1/2) protein phosphorylation believed to be involved in growth signalling pathway was evaluated by western blotting. TNF- released was assessed by total mRNA transcript via RT-PCR. Toxicity was assessed by the presence of liver transaminases aspartate amino transferase (AST) and alanine amino transferase (ALT) in serum.

Serum AST and ALT were within normal reference range in control and treated mice indicative of insignificant EtOH or clodronate induced toxicity. In KC+ mice fed EtOH hepatic DNA synthesis increased 183% compared to control KC+ mice. Hepatocyte DNA synthesis in KC– remain at the same level with control KC+ mice. In KC– mice fed EtOH there was a 50% decrease in hepatic DNA synthesis when compared to control KC+ mice and a 74% decrease compared to (KC+) mice fed EtOH-liquid diet. TNF- released was 148% in KC+ mice fed EtOH, 69% in KC– and 72% in KC– fed EtOH compared to control mice KC+. However, there was a slight increase in TNF- released in KC– fed EtOH-liquid diet when compared to KC– control. An increase in the phosphorylation of protein kinases p42/44 (ERK1/2) in the control mice KC+ fed EtOH was observed when compared to KC– mice fed ethanol. There was a slight increase in apoptotic bodies' accumulations in KC– fed EtOH-liquid diet and in KC– control mice.

Taken together these observations suggest that EtOH induces hepatocyte DNA synthesis in KC+ mice and to a lesser extent in KC– mice indicative of a role for the KC in hepatocyte DNA synthesis and may be involved in the development of hepatocarcinogenesis. Depletion of KC attenuates the downstream effect of ethanol induced endotoxemia, potentially by a mechanism involving reduced TNF- and ROS production with its concomitant effect on ERK 1/2 signaling pathway on hepatocyte DNA synthesis thereby supporting our hypothesis.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A45.

Abstract B45: Identification of chromosome aberration of oral squamous cell carcinoma patients in southern India

Thu, 07 Jan 2010 13:54:16 PST

Oral squamous cell carcinoma (OSCC) is the most frequent cancer and constitutes a major health problem in India, representing the leading cause of death. The aim of the present investigation was to study the major chromosomal aberrations (CA) like deletion, translocation, inversion and mosaic in OSCC patients of South India. Genetic factors play an important role in the etiology of OSCC. Totally 300 oral sumucosa fibrosis symptoms patients were chosen from various hospitals from southern india by advent screening like Toluidine blue staining and brush biopsy. Finally 103 severely affected OSCC patients were selected. 5ml of peripheral blood samples were taken from affected patients. Equal numbers of normal healthy control subjects were chosen after signing a consent form. Cytogenetic studies were performed by using Giemsa-banding technique and finally the results were ensured by spectral karyotyping (SKY) technique. In the present investigation, major CA like deletion, translocation, inversion and mosaic were identified in experimental subjects. Results showed frequent CA in chromosomes 3p, 3q, 8p, 7p, 9p, 11q, 17p, 19q and X. In comparison with experimental subjects, the control subjects exhibited very low levels of major CA (P<0.05). In the present study, the high frequency of centromeric rearrangements indicates a potential role for mitotic irregularities associated with the centromere in OSCC tumorigenesis, interesting chromosomal regions which may harbor susceptibility genes. Identification of chromosome alterations may be helpful in understanding the molecular basis of the disease in a better manner.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B45.

Abstract A46: The evidence base for the risk and management of thrombosis in hematological malignancy patients

Hassan, F. M. — Thu, 07 Jan 2010 13:54:04 PST

Background: The inflammatory response enhances the prothrombotic process via the action of potent inflammatory mediators, which induce further expression of procoagulants from tumor cells, activate platelets and induce endothelial expression of prothrombotic factors. Cancer treatment interventions, including surgery, chemotherapy, radiotherapy and the use of central venous catheters, all promote thrombosis, as does venous stasis due to restricted mobility and/or compression of vessels by a large tumor bulk.

Objectives: 1. To evaluate of hypercoagulable state and tumor procoagulant activity in hematological malignancies patients and 2. to address the primary thromboprophylaxis in medically managed, the optimum management of VTE and the prevention and treatment of VTE associated with central venous catheters.

Materials and Methods: Paper-based reply-paid questionnaire was distributed between patients, included the information about the duration, treatment used, sex, age, and type of malignant. We respectively analyzed 96 hematological malignancies patients treated for the prevention of recurrent venous thromboembolism and 33 control groups.the clinical analysis included thrombotic markers (protein S, protein C, PF1.2, TAT, PAI-1 and fibrin D-dimer) were done to all patients and control. Low-molecular weight heparin (LMWH) versus Oral anticoagulant frequency distribution were compared between cases and controls using statistical analysis.

Results: In total, 93 completed questionnaires were returned, respondents were reported the routine treatment of more than 10 types of haemopatopoietic and lymphoid tissues tumors. Of these, CML and CLL were most commonly treated (by 45%–62% of respondents), with lymphoma, plasma cell myeloma, AML, polythycythemia vera, and mast cell sarcoma the next most common (treated by 26%–38% of respondents). Most of patients (76%) showed a markedly elevation of PAI-1 and D-dimer and significantly elevated in whose treated surgically, while the other thrombotic markers (protein S, protein C, PF1.2, TAT were normal compared to control groups. 11% of 93 respondents who treat this tumor type surgically and 88% who treat it medically rated the risk of VTE as greater than 19%. Depending upon whether patients were managed surgically or medically, where most medically treated cancer patients were thought to have low risks, below 9%. The results showed that the LMWHs are effective for thromboprophylaxis in hematological malignance patients (56%) undergoing surgery and with central venous catheters, and for the initial treatment of VTE in cancer compared to oral anticoagulants.

Thromboprophylaxis was significantly more common for patients receiving chemotherapy for advanced disease (33% of respondents) than for those receiving adjuvant chemotherapy (12%) or undergoing surgery (3%).

Conclusion: There are several problems associated with the treatment of VTE in patients, especially with the use of oral anticoagulants, the onset of hypercoagulability, and raised risk of VTE. The true incidence of thrombosis by tumor type, stage of disease and antitumor intervention in the out-of-hospital cancer population is unknown.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A46.

Abstract B46: Celecoxib induces autophagy and apoptosis in human colorectal cancer cells: Strategies to enhance cell death

Huang, S., Sinicrope, F. A. — Thu, 07 Jan 2010 13:54:16 PST

Purpose: Celecoxib has been shown to induce cell death in conjunction with its chemopreventive effects. However, the mechanisms by which celecoxib induces cell death are incompletely understood. We determined whether celecoxib can induce autophagy, a process of cell destruction whereby cytoplasmic proteins and organelles are sequestered in vacuoles and delivered to lysosomes for degradation and recycling. Both apoptosis and autophagy have been shown to be negatively regulated by pro-survival Bcl-2 proteins, and the small molecule Bcl-2/Bcl-x_L antagonist (ABT-737), can enhance both processes. Since autophagy can be pro-survival or pro-death depending upon the cellular context, we determined whether autophagy inhibition can drive colon cancer cells into apoptosis.

Methods: HCT116 (wild-type and Bax^–/–), HT29, SW480 colorectal cancer cell lines were treated with celecoxib (0–120 µM) and/or ABT-737 (Abbott; 0–5 µM) in the presence or absence of a pan caspase inhibitor, z-VAD-fmk. Cell viability was determined using the MTS assay and apoptosis was analyzed by Annexin V FITC labeling. Immunoblotting was used to analyze caspase cleavage and LC3 conversion. GFP-LC3B cellular localization was determined by confocol microscopy. Autophagic flux was determined by LC3 immunoblotting in the presence of the lysosome inhibitor, bafilomycin A1. Knockdown of Bcl-x_L, Vps34 or Atg8/LC3B were achieved by lentiviral shRNA or siRNA.

Results: Celecoxib was shown to induce apoptosis that was attenuated by ectopic Bcl-2 or Bax knockout. ABT-737 synergistically enhanced celecoxib-induced apoptosis as shown by caspase cleavage and Annexin V labeling. Celecoxib also induced autophagy, as shown by conversion of the autophagosome-associated protein light chain 3 (LC3) from a cytosolic (LC3I) to a membrane-bound (LC3II) form as shown by immunoblotting, and a punctate fluorescence pattern of ectopic GFP-LC3 protein. Celecoxib-induced conversion of LC3 that was due to autophagy induction, as shown using the lysosome inhibitor, Bafilomycin A1 that produced an accumulation of LC3II. Furthermore, ABT-737 enhanced LC3 conversion by celecoxib. Autophagy inhibition was achieved using 3-methyladenine (3-MA), wortmannin or knockdown of Vps34 or Atg8/LC3B using siRNA. Inhibition of autophagy enhanced apoptosis as shown by caspase cleavage and Bid truncation in cells treated with celecoxib plus ABT-737. Furthermore, the addition of 3-MA to celecoxib plus ABT-737 produced a 5-fold increase in apoptosis that was associated with caspase cleavage and cytochrome c release.

Conclusions: Celecoxib induces both apoptosis and autophagy that can both be potentiated by ABT-737. Inhibition of autophagy was shown to potently drive cells into apoptosis, suggesting a novel therapeutic strategy against colon cancer cells.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B46.

Abstract A47: The anti-inflammatory role of statins and lung cancer chemoprevention

Young, R., Hopkins, R., Eaton, T. — Thu, 07 Jan 2010 13:54:04 PST

Recently published observational studies involving over 450,000 subjects have shown that statins confer protection from lung cancer with a risk reduction of up to 50% compared to those not taking statins (RR=0.50). Statins are known to inhibit the prenylation of GTPases (Rho, Rac, Ras), intracellular signaling molecules involved in upregulation of genes involved in inflammation, lung matrix remodeling and carcinogenic pathways. This pharmacological effect has been shown to occur at normal therapeutic doses. Lung cancer is thought to result from chronic cigarette exposure but occurs in only 10% of smokers. Chronic obstructive pulmonary disease (COPD), characterised by airflow limitation on lung function testing, is found in approximately 60–90% of lung cancer cases and is the most important risk factor for lung cancer in smokers. COPD results from smoke-induced matrix remodeling involving parenchymal destruction (emphysema), airway fibrosis (small airway narrowing) and epithelial proliferation. These processes are believed to be linked to lung cancer through epithelial-mesenchymal transition (EMT), a process whereby matrix remodeling leads to excessive growth factor mediated stimulation of epithelium and subsequent malignant transformation. These premalignant events are mediated by inflammatory cytokines (notably IL-6 and IL-8) released by bronchial epithelial cells following smoke exposure and whose matrix remodeling effects are mediated by GTPases. Statins are known to inhibit the actions of IL-6 and IL-8 by GTPase inhibition thereby inhibiting the upregulating effects of these cytokines on inflammation. Pre-clinical studies show that inhibition of the GTPases can reduce or even reverse EMT. Studies also show that IL-6 is elevated in lung cancer and that anti-IL-6 activity can prevent carcinogensis. Together these observations suggest that statin therapy could, through down regulation of GTPases, inhibit the initiation of lung cancer through inhibition of the upregulatory effects of inflammatory cytokines such as IL-6. Such a mechanism would explain the possible chemo preventive actions of statins, on the development of lung cancer. Further studies are needed to establish the role of statins in inhibiting EMT and malignant transformation leading to lung cancer.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A47.

Abstract B47: External Qi of Yan Xin Qigong induces cell cycle arrest and apoptosis in colon cancer cells through regulation of multiple signaling pathways

Yan, X., Shen, H., Jiang, H., Hu, D., Zhang, C., Wang, J., Wu, X. — Thu, 07 Jan 2010 13:54:16 PST

The concept external Qi of Qigong refers to the technology and ability of "Qi deployment" therapy and health preservation of traditional Chinese medicine (TCM). External Qi therapy of TCM has long been one of the medical practices in China. Long-term clinical observations and ongoing studies have shown positive effects of external Qi of Yan Xin Qigong (YXQ-EQ) on patients of various types of cancer. The molecular and cellular mechanisms underlying YXQ-EQ's antitumor effects have recently begun to be addressed. In the present study we investigated YXQ-EQ's effects on the growth and apoptosis of human colon carcinoma HT-29 cells. We show that YXQ-EQ treatment reduced the viability and inhibited clonogenic growth of HT-29 cells. In agreement, YXQ-EQ induced cell cycle G1 arrest and apoptosis in HT-29 cells. YXQ-EQ induced apoptosis is accompanied by DNA fragmentation and cleavage of procaspase-3 and -9 and poly(ribose-ADP) polymerase. YXQ-EQ inhibited phosphorylation of Akt and GSK3β, decreased the levels of cyclin D1 and hyper-phosphorylated Rb, and repressed the expression of antiapoptic proteins Bcl-X_L, XIAP, and survivin. Concomitantly, YXQ-EQ increased the expression of cyclin-dependent kinase inhibitor p21^CIP1/WAF1. These findings suggest that YXQ-EQ may induce cell cycle arrest and apoptosis in colon cancer cells through regulation of multiple signaling pathways that play important roles in cell proliferation, survival and apoptosis.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B47.

Abstract A48: In vivo evaluation of Cox-2 inhibition to prevent the progression of invasive urinary bladder cancer

McMillan, S., Biolsi, S., Bonney, P., Stewart, J., Knapp, D. W. — Thu, 07 Jan 2010 13:54:04 PST

Background: Invasive transitional cell carcinoma (InvTCC) of the urinary bladder has a propensity to metastasize, is only partially responsive to chemotherapy, and causes > 14,000 deaths yearly in the United States. The development of effective means to prevent the development and progression of InvTCC is crucial. Cyclooxygenase-2 (Cox-2) is over-expressed in InvTCC in humans and animals. In a pilot study, a Cox-2 inhibitor induced apoptosis of InvTCC in humans. Cox-2 inhibitors may offer an avenue for prevention of InvTCC progression. The purpose of this study was to determine the effects of Cox-2 inhibitor treatment in preventing the progression of InvTCC in a highly relevant animal model, canine InvTCC. Naturally-occurring InvTCC in dogs closely mimics human InvTCC in cellular and molecular features (including Cox-2 expression), sites and frequency of metastasis, and response to therapy.

Methods: Dogs with histologically confirmed InvTCC who failed or whose owner declined standard chemotherapy protocols, and with expected survival of > 6 weeks were prospectively enrolled. The Cox-2 inhibitor deracoxib (Novartis, Greensboro, NC) was given as a single agent with a planned dose of 3mg/kg/day orally. Dogs were evaluated prior to and during therapy with abdominal ultrasound including mapping of the urinary bladder masses, thoracic radiographs, complete blood count, serum biochemistry profiles and urinalyses. Toxicity was assessed by clinical signs and serial blood work. Tumor response was defined as: complete remission (CR), no evidence of disease detected; partial remission (PR) ≥ 50% reduction in tumor volume; stable disease (SD) <50% change in tumor volume; or progressive disease (PD) ≥ 50% increase in tumor volume or new lesions. A whole blood assay was used to confirm selective Cox-2 inhibition.

Results: Thirty-nine dogs with InvTCC received deracoxib at a mean dose of 2.79 mg/kg/day (range 1.18 mg/kg/day to 4.08mg/kg/day). Of 39 dogs, 1 had nodal metastasis, and 3 had distant metastasis at diagnosis. Initial responses in 30 dogs with measurable disease included PR in 4 dogs (13%), SD in 17 dogs (57%), and PD in 3 dogs (10%); and in 6 dogs, response to therapy has not been determined. Mean time to subsequent PD (n=20) was 167 days (range 36 – 482 days). After PD was noted, 10 dogs went on to receive other therapy (leukeran, mitoxantrone, mitomycin-C, 5 azacitidine, carboplatin). Of the 39 dogs treated, 9 had microscopic residual disease after surgical intervention. Of these 9 dogs, 4 had relapse (median time to relapse, 221 days), and 3 had not relapsed at the time of death from other causes (median time to death 772 days). The median survival times for dogs with measurable disease and microscopic disease were 349 and 772 days, respectively.

Conclusion: The results of this work help justify further study of the use of Cox-2 inhibitors in preventing the progression of InvTCC.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A48.

Abstract B48: Xanthohumol from hops (Humulus lupulus L.) reactivates epigentically silenced genes by potential DNA methyltransferase inhibition

Thu, 07 Jan 2010 13:54:16 PST

Epigenetic silencing of tumor suppressor genes by DNA hypermethylation is now recognized as a hallmark of cancer. Thus, reversal of DNA hypermethylation by demethylating agents and DNA methyltranserase (Dnmt) inhibitors has been extensively investigated. Recently, several studies have shown that natural dietary compounds have the potential to reactivate epigenetically silenced genes by various mechanisms, which might have an impact on chemoprevention strategies.

Xanthohumol (XN), a prenylated chalcone from hops, exerts a broad spectrum of chemopreventive actions and inhibits mammary carcinogenesis in vivo. In this study, we report for the first time that epigenetic deregulation of gene expression during carcinogenesis is a novel target of XN action. We demonstrated that XN reactivates a series of candidate genes silenced by DNA promoter hypermethylation in human cancer cell lines. By treating human breast and prostate cancer cell lines MCF-7 and LNCaP with subtoxic XN-concentrations for 48 and 72h, respectively, we observed significant dose-dependent re-expression of glutathione-S-transferase (GSTPi), Cyclin D2 and RassF1A mRNA, measured by quantitative RT-PCR. The demethylating agent 5-aza-2'-deoxycytidine (5-aza-dC) was used as positive control. To address if the XN-mediated mechanism of gene re-expression involved inhibition of Dnmt activity, we tested XN in an in vitro system using the bacterial methlytransferase M.SssI as an enzyme source. XN at concentrations ranging from 3.13–50 µM dose-dependently inhibited M.SssI activity with a halfmaximal inhibitory concentration of 35.2 µM (p<0.05). Computational modelling of XN docking to Dnmt1 indicates steric interaction with the active site. In addition, in MCF-7 and LNCaP cells treated with XN, expression of Dnmt1, 3a and 3b was inhibited by XN-treatment in a dose-dependent manner, both at the transcriptional (p<0.05) and protein level. Next, demethylating potential of XN was investigated. DNA of XN-treated MCF-7 and LNCaP cells was subjected to quantitative methylation analyis using the Sequenom Massarray platform. Whereas treatment for 72h with 1µM of 5-aza-dC significantly reduced DNA hypermethylation of promoter CpG islands of GSTPi, Cyclin D2 and RassF1A by 10–20% (p<0.05), XN-treatment with 5–10µM did not show general DNA demethylation. However, individual CpG sites in the analyzed regions were strongly demethylated upon XN-treatment. Ongoing studies investigate whether demethylation of these single CpG sites is crucial for active transcription, and whether this can be correlated to induced gene-expression.

In conclusion, we demonstrated that XN reactivates the expression of hypermethlyated genes by inhibition of Dnmt activity, expression and demethylation of selected CpG sites, which represents a novel chemopreventive mechanism by XN.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B48.

Abstract A49: Evidence for gene demethylation in human colon cancer by black raspberries

Thu, 07 Jan 2010 13:54:04 PST

Black raspberries (BRBs) exhibit cancer preventative effects in the human colon, in part, by reducing the growth rate and increasing the apoptosis of human colon tumor cells. Recently, we have initiated investigations to determine whether BRBs also cause re-expression of genes in human colon cells that are silenced by aberrant hypermethylation. Cultured human colon cancer cell lines HCT116, Caco2 and SW480, were treated with an anthocyanin-rich (AC) fraction of BRBs every day for five days. AC treatment caused a decreased activity of DNA methyltransferases in a substrate-antibody assay (p<0.05) and a reduction of DNMT1 protein expression. Direct analysis of methylation changes in the promoter region of the suppressor gene p16 (CDKN2A) by Sequenom MassARRAY/EpiTYPER demonstrated a decrease in methylation of all eight p16 promoter CpG units, each unit containing 1–3 CpG sites. All cell lines treated with AC had a significant increase in apoptosis and a decrease in cell proliferation as compared to untreated cells (p< 0.05).

These in vitro observations were confirmed by the examination of normal and tumorous tissue samples taken from 20 colon cancer patients who received daily dietary intervention of freeze-dried BRB powder (60g/day) in drinking water for an average of 3 weeks. DNA from the tissue samples was analyzed by MassARRAY which revealed an overall decrease in p16 methylation in both normal and tumor tissues (p<0.05).

Immunohistochemical analysis of p16 and DNMT1 in the same tissue samples showed that BRB treatment increased p16 expression and decreased DNMT expression (p<0.05), both correlating with decreased methylation of the promoter region of the gene. In addition, the expression levels of Ki-67 and c-myc, both markers of cell proliferation, were reduced in berry treated samples, however, only the reduction in Ki-67 was significant (p<0.05). These data suggest that BRBs are capable of reversing aberrant methylation in both normal and tumorous human colon tissues at tolerable amounts in the diet. This effect appears to be caused by inhibition of DNMT family enzymes, and most likely DNMT1. Supported by NCI grant CA103180 and USDA grant 38903-03560.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A49.

Abstract B49: Epigenetic changes during disease progression in a murine model of human breast cancer

Thu, 07 Jan 2010 13:54:17 PST

It is now well accepted that epigenetic alterations contribute to tumorigenesis. DNA methylation has been recognized as an early and possibly initiating event in the development of breast cancer and thus represents a potentially valuable marker for early detection and chemoprevention.

In the present study, we aimed to characterize DNA methylation changes associated with the development of breast cancer in the C3(1)/SV40 large T-antigen transgenic mouse model of mammary carcinogenesis. This model has been utilized in various studies to demonstrate chemopreventive efficacy of both natural products as well as pharmacological agents such as green and black tea or the COX-2 inhibitor celecoxib.

For DNA methylation analyses, wildtype (wt) and transgenic (tg) mice were sacrificed at 4–24 weeks of age to collect mammary and tumor tissue, respectively. Initially, we selected eight candidate genes know to be silenced by hypermethlytion in human breast cancer: Cadherin1, Cyclin D2, RASSF1a, Timp3, Twist, GST, SMPD3, and GHSR1a. DNA methylation of CpG islands associated with these genes was quantified by EpiTYPER MassARRAY technology based on mass spectrometry. Interestingly, none of these genes was hypermethylated in murine tumors. On average, we detected less than 16% methylation, which was not significantly different between wt and tg tissue and did not change with age.

Consequently, we next decided to analyze methylation changes at a genome-wide level, using methylation-specific DNA array analysis after methyl-CpG immunoprecipitation (MCIp). Hypermethylated DNA of age-matched wt and tg animals was enriched by binding to recombinant methyl-CpG-binding domain protein MBD2. Dual-color labeled samples were then hybridized to Agilent murine CpG island microarrays containing oligonucleotide probes for >16.000 CpG islands. Based on data obtained with tissue derived of animals aged 16–24 weeks, we selected genes commonly hypermethylated in tg mice for subsequent validation by MassARRAY analysis. As an example, five genes, Mab21l2, Lyl1, Atp6v1b1, Espn, A930037G, showed significant hypermethylation in a range of 52 to 69% in tumor tissue of mice aged 24 weeks, whereas an average methylation of 6 to 15% was detected in mammary tissue of age-matched wt animals. Interestingly, when we analyzed mammary tissue of mice at increasing age, we observed a gradual increase in hypermethylation in tg vs. wt animals for all selected genes, starting at 12–16 weeks of age even before tumors were detected. These data indicate a potential early role of deregulated DNA methylation in C3(1)/SV40 large T-antigen-induced mammary carcinogenesis. The newly identified genes, which have rarely been investigated in relation to human breast cancer so far, may serve as interesting targets for chemoprevention studies and will be further characterized.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B49.

Abstract A50: Black raspberry treatment in FAP patients shows re-expression of methylation-silenced genes

Thu, 07 Jan 2010 13:54:04 PST

In a clinical trial, we found that freeze-dried black raspberry (BRB) powder reduced the number of rectal polyps in patients with familial adenomatous polyposis (FAP). The present study was undertaken to determine if the berries influenced the growth and apoptosis of cells in rectal polyps. In addition, because the p16 tumor suppressor gene is inactivated by methylation in greater than 60 percent of colon tumors, we examined the levels of both p16 and of DNA methyltransferase 1 (DNMT1) expression in normal and polyp specimens. DNMT1 has been shown to be overly expressed in cultured human colon cancer cell lines and this correlated with silencing of the p16 gene. Polyps and normal tissues were obtained from FAP patients before and after 36 weeks of berry treatment. Immunohistochemical staining for Ki-67 and c-MYC showed that cell proliferation was significantly reduced by berry treatment in both normal rectum and in rectal polyps. TUNEL staining for apoptosis was observed to increase significantly in both normal rectum and in rectal polyps. There was a significant decrease in DNMT1 expression and an increase in p16 expression in berry-treated normal and polyp specimens. These results suggest that nine months of black raspberry treatment resulted in reduced cell proliferation, increased apoptosis and p16 gene expression and decreased DNMT1 expression in both normal and polyp specimens taken from FAP patients. The p16/DNMT1 data suggest that black raspberries may act as a demethylating agent and should be further evaluated for their effects on the methylation status of other candidate tumor suppressor genes in colonic polyps and tumors. This research was supported by NCI grant CA103180 and USDA grant 38903-03560.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A50.

Abstract B50: Promoter methylation of the BRCA1 gene in young breast cancer patients with no significant family history

Gutierrez-Barrera, A. M., Litton, J., Hortobagyi, G. N., Arun, B. K. — Thu, 07 Jan 2010 13:54:17 PST

Background: Premenopausal breast cancer represents < 25% of all breast cancers, and only 5–10% of all breast cancer can be attributed to mutations in BRCA1/2 genes. Therefore, 90–95% of premenopausal patients may have a sporadic form of breast cancer. Although these women do not have germline mutations in the BRCA genes, it is possible that epigenetic modifications which lead to BRCA gene silencing may play a role in these sporadic cases. Previous research has identified epigenetic changes in the BRCA1 gene in as many as 10–20% of sporadic cases (1). More recently, other investigators used peripheral blood cells (PBC) to evaluate the presence of somatic methylation of the BRCA1 promoter and suggested that promoter methylation in normal PBC can be identified and correlated with development of triple negative breast cancer. However, currently the presence and rate of BRCA1 promoter methylation is not well described in subsets of breast cancer. Therefore, in this current study our aim was to examine PBC of premenopausal breast cancer patients diagnosed at or under 40 who had no detectable BRCA1 mutations in an effort to correlate BRCA1 promoter methylation with premenopausal breast cancer development.

Methods: 28 patients with a history of breast cancer or ductal carcinoma in situ (DCIS) who tested negative for a deleterious mutation in the BRCA1 gene were enrolled in the study. Median age was 36.5 (range 28–47). Twenty-two (78.6%) of the patients had a positive family history of breast and or ovarian cancer, other patients were tested for BRCA mutations on the basis of their young age. Three (10.71%) had DCIS, 2 (7.14%) had stage I, 14 (50%) had stage II, 7 (25%) stage III, and 2 (7.14%) stage IV breast cancer. The estrogen receptor (ER) was positive in 21 (75%) of the samples, progesterone receptor (PR) in 15 (53.56%) and Her-2/neu was positive (based on IHC scores of 2 or 3 +, or FISH +) in 15 (53.56%) of the patients. Four (14.29%) of the tumors were ER, PR, and Her-2/neu (triple) negative. At the time of sample collection, 7 patients (25%) were chemotherapy naive and 21 patients (75%) had received chemotherapy. DNA was extracted from PBC then subjected to bisulfite conversion (Invitrogen, MethylCode Bisulfite Conversion kit) and the promoter region was examined using methylation-specific PCR techniques (–157 to +57, +1 serving as transcription start site).

Results: We observed that 3 out of 28 PBCs displayed BRCA1 promoter methylation. Promoter methylation did not correlate with any certain subgroups; however, the numbers of subjects are too small at this point.

Conclusions: These preliminary results suggest that 10.7% of sporadic breast cancers have a somatic promoter methylation in the BRCA1 gene. This finding might be important for the development of this test in the assessment of breast cancer risk of women who have no deleterious BRCA1 mutations. Further studies are ongoing to evaluate these promoter methylations in women who are at increased risk for breast cancer.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B50.

Abstract A51: Comparison of different berry types to prevent chemically induced papilloma development in the rat esophagus

Chiu, S., Seguin, C., Stoner, K., Rocha, C., Wang, L.-S., Stoner, G. D. — Thu, 07 Jan 2010 13:54:04 PST

The present study compared the ability of seven different berry types [black and red raspberries, strawberries, blueberries, acai, noni, goji (wolfberry)] to inhibit N-nitrosomethylbenzylamine (NMBA)-induced tumor development in the F344 rat esophagus. These seven berry types have been shown to differ in their relative content of known chemopreventive agents such as anthocyanins, ellagitannins and carotenoids. Each berry type was picked when ripe, freeze-dried under anoxic conditions to prevent decomposition of their chemical components, and ground into a powder. Beginning at 4 weeks of age, 120 F344 rats were injected with NMBA (0.3 mg/kg, 3x/wk for 5 weeks). Control rats (15) were injected with DMSO/water (80:20), the solvent for NMBA. Beginning one week after treatment with carcinogen, individual berry types were administered at 5% of the diet to groups of 15 NMBA-treated rats until the end of the bioassay (35 weeks). At necropsy, the number of esophageal papillomas was enumerated in all groups of rats. No papillomas were seen in control rats treated with DMSO/water. All berry types caused a significant reduction in the number of NMBA-induced papillomas when compared to rats treated with NMBA only. There was no significant difference in the relative ability of the different berry types to reduce tumor incidence, multiplicity or size. Histopathological studies showed that each berry type was about equally effective in preventing the conversion of preneoplastic lesions (dysplasias) to papillomas. These results suggest that the chemopreventive potential of berries for the rat esophagus is not restricted to black raspberries and strawberries as shown previously in our laboratory. They also suggest that berries that vary markedly in their content of anthocyanins, ellagitannins and carotenoids all exhibit chemopreventive potential in the rat esophagus. Supported by NCI grant CA103180 and USDA grant 38903-03560.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A51.

Abstract B51: Discovery of novel genomic targets in the NRF2-mediated antioxidant response pathway by ChIP-on-chip and ChIP-seq

Thu, 07 Jan 2010 13:54:17 PST

Sulforaphane is a dietary isothiocyanate that has been shown to have anticancer, antidiabetic and antimicrobial properties. Found in cruciferous vegetables, sulforaphane acts primarily as a phase II enzyme inducer through the pathway mediated by nuclear factor (erythroid-derived 2)-like 2 (NRF2). NRF2 is the key transcriptional activator in this pathway, binding as a heterodimer with small Maf proteins to cis-acting antioxidant response elements (AREs) found in the promoter regions of downstream oxidative response genes. In Nrf2 knockout mice, oxidative stress exposure causes increased damage to lung, liver and neurological tissue compared to wild type mice. Conversely, an aggressive cancer phenotype has been linked to permanently activated NRF2; indicating NRF2 may directly regulate other pathways unrelated to oxidant defense. In order to investigate NRF2 binding and gene regulation on a genome wide scale, we analyzed chromatin immunoprecipitated (ChIP) NRF2-bound DNA using ChIP-on-chip and ChIP-Seq technologies. Specifically, a human lymphoblastoid cell line (HapMap GM11994) was exposed in triplicate to 10uM sulforaphane, crosslinked, sonicated and immunoprecipitated with NRF2 antibody. NRF2-bound DNA was amplified and hybridized to the Agilent Human Promoter chip, which provides –5.5 to +2.5 kilobase coverage around the majority of gene transcriptional start sites (ChIP-on-chip). Additionally, ChIP NRF2-bound DNA was sequenced using the Solexa GAII second-generation sequencing platform (ChIP-seq). ChIP-on-chip intensity data was input to Agilent's DNA analytics software and 1056 probes in promoter regions of 277 genes displayed sulforaphane - induced NRF2 binding, 20 of which had been previously identified as NRF2-regulated genes. Ingenuity pathway analysis found these 277 genes were involved in oxidative stress, cellular growth and proliferation, cellular development, small molecule biochemistry and other signaling pathways. We cross referenced the ChIP-on-chip data with results from gene expression (induction>1.2-fold/suppression <0.8-fold compared to control, p<2.5X10^–6) in 60 sulforaphane-exposed HapMap lymphoblastoid cells lines as determined by Illumina microarray. We identified 32 differentially expressed genes with NRF2 binding, 17 that had not previously been described as regulated by NRF2. Preliminary analysis of the ChIP-seq data has mapped 2.1 million uniquely aligned sequencing reads resulting in 945 bound regions (high quality peaks). Of these, 5% are located near known NRF2-binding regions, and approximately 20% of the regions overlap with the ChIP-on-chip platform. Using both the ChIP-on-chip and ChIP-seq platform in this study has allowed us to investigate NRF2 on a genome-wide scale and identify novel sulforaphane-activated NRF2 gene targets.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B51.

Abstract A52: Characterization of Indian honey and its anticancerous activity against colon cancer

Mandal, M., Jaganathan, S. K. — Thu, 07 Jan 2010 13:54:04 PST

Four multifloral honey types from different Indian origin (named as Samples A, B, C and D) were analyzed for their phenolic acids using high performance liquid chromatography (HPLC). HPLC-Mass Spectroscopy analysis revealed that dihydroxy benzoic acid, caffeic acid, ferulic acid and cinnamic acid were the major phenolic acid constituents of the tested honey. The total antioxidant potential and free radical scavenging ability varied among the honey samples and exhibited a significant correlation with their phenolic content. Further the honey samples were studied for rheology and thermal properties. Controlled shear rate viscometry indicated the Newtonian behavior (a drop in the viscosity as the temperature increases) in the honey samples. Differential Scanning Calorimetry (DSC) analysis revealed the inflection transition temperature (Tg) of the honey samples ranged between - 51.40 °C to –30.64 °C. Thiazolyl blue tetrazolium bromide (MTT) assay revealed that the honey samples containing higher phenolic content showed significant antiproliferative effect against colon cancer cells. From the abovesaid experiments, Sample C among the four was found to be better based on its phenolic, antioxidant and antiproliferative effects and chosen for further studies. Honey induced the apoptotic signal via initial depletion of intracellular non protein thiols, consequently reducing the mitochondrial membrane potential (MMP) and increased the reactive oxygen species (ROS) generation. P53 up-regulation and modulation of pro and antiapoptotic proteins were observed in the honey induced apoptosis. The work was extended further to study the constituents of honey that induced apoptosis. For this, we screened the antiproliferative effect of some reported phenolic constituents namely p-coumaric acid, caffeic acid, gallic acid and eugenol in colon cancer cells. We had selected eugenol based on their better antiproliferative nature and elucidated the mechanism. Eugenol treatment resulted in reduction of intracellular non-protein thiols and increase in the earlier lipid layer break. Further events like dissipation of mitochondrial membrane potential and generation of ROS were accompanied in the eugenol-induced apoptosis. Finally we had studied the anticancer activity of honey samples (Samples B and C) and eugenol against Ehrlich ascites carcinoma. We found that Sample C remarkably inhibited the tumor growth by 40 % compared to Sample B (12.17 %) against Ehrlich ascites carcinoma when given 25% v/v intraperitoneally (i/p). We had found eugenol with a dose of 100 mg/Kg showed nearly 29% tumor inhibition.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A52.

Abstract B52: MicroRNAs and SEL1L gene regulation in human pancreatic ductal adenocarcinoma

Liu, Q., Chen, J., Amos, C., Killary, A., Sen, S., Frazier, M. — Thu, 07 Jan 2010 13:54:17 PST

Pancreas-specific tumor suppressor gene SEL1L is downregulated at both the mRNA and protein levels in a significant proportion of human pancreatic ductal adenocarcinoma (PDAC) cases. We sought to use statistical methods to determine if one or more aberrantly upregulated microRNAs (miRNA) are responsible for the repression of SEL1L, which would help elucidate the role of specific miRNAs in PDAC.

Based on published microRNAs microarray data and miRNA targets prediction resource, we initially identified seven miRNAs for our study which were reported to be upregulated in PDAC and potentially target SEL1L. Using real-time PCR, we quantitatively assessed the expression levels of SEL1L mRNA and these miRNAs in 42 pairs of PDAC samples and matched normal adjacent tissues. Fisher's Exact Test and Kruskal-Wallis Test were applied to evaluate the correlation between SEL1L and the miRNAs.

Our results showed that the expression of SEL1L mRNA inversely correlates with the expression of 3 miRNAs (P < 0.0001, P < 0.0001 and P = 0.002, respectively). As the number of these overexpressed miRNAs increase from 0 to 3, we observed progressively increasing downregulation of SEL1L (P – trend = 0.001).

Our findings suggest that the 3 miRNAs work cooperatively to repress SEL1L mRNA expression. These specific miRNAs may serve as useful biomarkers for PDAC.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B52.

Abstract A53: Chemoprevention of colon cancer by PBIT, an iNOS-selective inhibitor, administered alone or in combination with low-doses of celecoxib, a COX-2 selective inhibitor

Rao, C. V., Guruswamy, S., Patlolla, J. M. R., Janakiram, N., Malisetty, V. S. — Thu, 07 Jan 2010 13:54:05 PST

Clinical and preclinical studies suggest that NSAIDs and cyclooxygenase (COX)-2 inhibitors such as celecoxib, reduce the risk of colorectal cancer. However high doses of NSAIDs causes gastrointestinal toxicity and increased cardiovascular risk. Inducible nitric oxide synthase (iNOS), like COX-2, is overexpressed in colon tumors. Interestingly, nitric oxide stimulates COX-2 activity and contributes to the tumor growth. The present study examines the effects of S,S'-1,4-phenylenebis(1,2-ethanediyl)bisisothiourea (PBIT), an iNOS-selective inhibitor on 1) azoxymethane (AOM)-induced colon adenocarcinomas in F344 rats 2) evaluates the combined effects of a low-dose PBIT and celecoxib on chemopreventive efficacy in rats. Seven-week old male F344 rats (36/group) were fed control AIN-76A diet and one week later, AOM was administered s.c to induce colonic tumors. Four-weeks after the AOM treatment, groups of rats were fed experimental diets containing either 0, 50, 100 ppm of PBIT or 250 and 500 ppm of celecoxib or a combination of 50 ppm PBIT plus 250 ppm celecoxib. Forty-eight weeks after AOM treatment, rats were killed and the intestinal tumors were evaluated. Multiple samples of colonic tumors from each group were assayed for expression and activity of iNOS, COX-2 and markers of apoptosis and cell proliferation. We found that 50 and 100 ppm PBIT in diet suppressed colon adenocarcinoma incidence by 34.6% (p<0.01) and 43% (p<0.002), respectively. Similarly, dietary PBIT suppressed adenocarcinoma multiplicity by 40% (p<0.05, 50 ppm) and 60% (p<0.006, 100 ppm). Celecoxib at both 250 and 500 ppm significantly suppressed colon adenocarcinoma incidence (55–77%, p<0.002-0.0001) and multiplicity (66–82%, p<0.002 - 0.0002). A low-dose combination of 50 ppm PBIT and 250 ppm celecoxib significanlty suppressed colon adenocarcinoma incidence by 70% and multiplicity by 83% (p<0.0001). Interestingly, a combination of low-dose PBIT and celecoxib produced either equal or increased inhibitory effect when compared with high dose PBIT or celecoxib alone. Rats fed PBIT and/or a combination of PBIT plus celecoxib showed considerable suppression of iNOS (38–59%, p<0.01-0.0001 and COX-2 (44–67%, p<0.0001) activities and increased p21^WAF1/CIP expression in colonic tumors. Administration of 100 ppm PBIT, 250 ppm or 500 ppm celecoxib and a combination of 50 ppm PBIT plus 250 ppm celecoxib suppressed tumor cell proliferation (BrdU index by 22–53%, p<0.05-0.0001) when compared with colon tumors from the control group. Significant levels of apoptotic cells were observed in the adenocarcinomas of celecoxib fed rats and also in rats fed with a combination of low-dose PBIT and celecoxib. These observations demonstrate, for the first time, that the iNOS-selective inhibitor possesses dose-dependent chemopreventive activity in well-established models of colon cancer and a combination of low-dose PBIT and celecoxib significantly enhanced colon cancer chemopreventive efficacy. [Supported by NIH grants R01-CA-102947]

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A53.

Abstract B53: Identifying functional polymorphisms that alter sulforaphane-induced gene expression via the NRF2 pathway

Chorley, B. N., Wang, X., Campbell, M. R., Kleeberger, S. R., Bell, D. A. — Thu, 07 Jan 2010 13:54:17 PST

Dietary isothiocyanates derived from the consumption of broccoli and other cruciferous vegetables have been shown to prevent cancer in various animal and clinical studies. Sulforaphane has been extensively used in mouse liver and lung studies to assess both anticancer effects and oxidant-induced gene transcriptional profiles. Sulforaphane imparts its antioxidant effects by activating the nuclear factor (erythroid-derived 2)-like 2 (NRF2) pathway. NRF2 is a key transcriptional activator of antioxidant and phase II drug metabolism enzymes that regulate transcription by binding cis-acting antioxidant response elements (AREs) found in gene promoter regions. Since genetic factors, such as loss of function deletions in drug metabolism genes like glutathione-S-transferases, can influence the effectiveness of chemopreventive or chemotherapeutic agents, we hypothesized that single nucleotide polymorphisms (SNPs) within ARE sequences located in NRF2 target genes may alter sulforaphane-induced transcriptional regulation of these enzymes. To assess this, we exposed 60 unrelated, HapMap CEU cell lines to sulforaphane and measured global gene expression with Illumina gene expression arrays. We observed 2946 expression probes were either significantly induced (1436) or suppressed (1510) in at least 6 of the 60 cell lines by a fold change of 1.3 or greater (t-test with FDR correction, p<0.09). Pathway analysis of induced genes indicated these genes are involved in oxidative stress response, apoptosis signaling and peroxide metabolism. SNP genotypes (identified by the HapMap project and our custom genotyping arrays) within a gene region were regressed against log₂-transformed intensity values for each gene. Of the 11,566 SNPs that were significantly associated with gene expression after sulforaphane treatment (linear regression, p<0.05), 972 SNPs were located within putative AREs identified by bioinformatics analysis and 55 SNPs were within 10kB of the transcriptional start site of a known ARE gene. To verify binding of NRF2 in these regions, NRF2-bound DNA isolated from a sulforaphane treated lymphoblastoid cell line was immunoprecipitated and analyzed by Agilent ChIP-on-chip. We observed that 23 of the 1027 selected SNPs were located near NRF2 bound regions. Three of these SNPs were located directly within ChIP-on-chip probe regions. This study provides promising SNP candidates for follow-up in molecular validation and clinical disease association studies. Functional SNPs that alter the binding potential and gene transactivation by NRF2 may help explain individual variation in the response to agents that modulate antioxidant and phase II enzyme regulation and subsequent clinical outcome.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B53.

Abstract A54: Combining the rexinoid bexarotene with tamoxifen to prevent ER-negative mammary tumors in MMTV-erbB2 mice

Mazumdar, A., Zhang, Y., Brown, P. H., Hilsenbeck, S. G., Bissonnette, R. — Thu, 07 Jan 2010 13:54:05 PST

Background: Retinoids, vitamin A analogues that bind to retinoic acid receptor (RAR), play an important role in regulating cell proliferation and differentiation. Our previous studies demonstrated that related molecules, rexinoids (Bexarotene (LGD1069) and LGD100268), that bind the RXR receptor, suppress but do not totally prevent ER-negative mammary tumorigenesis. Using a transgenic mouse model of ER-negative breast cancer (MMTV-erbB2 mice), our laboratory demonstrated that bexarotene delays but does not totally prevent ER-negative mammary tumorigenesis with minimal toxicity. We hypothesized that bexarotene in combination with the anti-estrogen drug tamoxifen would more effectively prevent the development breast cancer. To test this hypothesis we treated MMTV-erbB2 mice with bexarotene, tamoxifen, or the combination from the age of 3 months to 9 months and monitored the mice for mammary tumors.

Methods: Virgin MMTV-erbB2 mice at age of 3 months were used for these studies. A defined diet was used (AIN-76A). Mice were randomized into 4 groups (10 mice per group): 1) Tamoxifen control (Sham pellets) and bexarotene control (sesame oil), 2) Tamoxifen control (Sham pellets) and bexarotene (50mg/kg), 2) Tamoxifen pellets (2.5mg/pellet, 90-day-release) and bexarotene control (sesame oil), 4) Tamoxifen pellets (2.5mg/pellet, 90-day-release) and bexarotene (50mg/kg). Tamoxifen or sham pellets were replaced once after 90 days to deliver 180 days of tamoxifen (from age 3 months to 9 months). Bexarotene or sesame oil control was administered by gastric gavage daily (5 days per week) for 180 days (from age 3 months to 9 months). The mice were observed daily for tumor formation, weights were recorded weekly, and tumors were measured twice a week. Mice were sacrificed when tumor sizes exceeded 1500mm³. Analysis of time to tumor formation (defined as the time to develop a 100mm³ tumor) was the primary endpoint of these studies. Analysis of the expression of mammary tissue biomarkers is ongoing.

Results: Bexarotene and tamoxifen as single agents slightly delayed the development of mammary tumors in these mice. However, the combination of bexarotene and tamoxifen was much more effective. By 350 days of age, 100% of the control animals developed mammary tumors, while only 10% of the animals treated with bexarotene and tamoxifen developed mammary tumors. This difference in time to tumor development is highly statistically significant (p <0.05; Generalized Wilcoxon test). These mice are still being followed, and updated results will be presented. We are now conducting biomarker studies to measure the effect of tamoxifen, bexarotene, and the combination on the expression of the erbB2 transgene, the estrogen receptor, and on markers of proliferation (Ki67 and cyclin D1) and apoptosis (cleaved caspase 3).

Conclusions: The combination of bexarotene and tamoxifen is highly effective at preventing ER-negative mammary tumors in MMTV-erbB2 mice. These preclinical results suggest that combining a rexinoid with an anti-estrogen drug may be useful to prevent both ER-positive and ER-negative breast cancer in humans. These studies were supported by NIH R01 grants (CA101211) and by a Breast Cancer SPORE grant (P50 CA58183).

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A54.

Abstract B54: The anticancer effects of calorie restriction on MC38 colon tumors are associated with decreased macrophage infiltration

Harvey, A. E., Otto, G., Nunez, N. P., Perkins, S. N., Hursting, S. D. — Thu, 07 Jan 2010 13:54:17 PST

Obesity is a risk factor for a number of chronic diseases including many types of cancer. The chronic, low-grade inflammation that develops as a result of obesity may be a primary mechanistic target underlying obesity-associated carcinogenesis. While the link between obesity and inflammation is not well understood, increases in adipose tissue macrophages may perpetuate and exacerbate a chronic inflammatory environment through production of inflammatory cytokines such as interleukin (IL)-6. In this study we tested the hypothesis that macrophage infiltration underlies our previously observed anticancer effects of calorie restriction (CR) in a mouse model of colon cancer. Six-week-old female C57BL/6 mice (n=30 per diet) were singly housed and randomized to either a control diet consumed ad libitum (which results in an overweight phenotype) or a 30% calorie-restricted diet regimen (CR) for 22 weeks, at which time 15 mice per group were euthanized and adiposity was measured using dual-energy X-ray absorptiometry (DXA). The remaining 15 mice/diet were then injected subcutaneously (flank) with 50,000 syngeneic mouse colon (MC)-38-adenocarcinoma cells and continued on their diet regimens while tumor growth was monitored for an additional 5 weeks. Excised tumors underwent histological analysis of macrophage infiltration (hematoxylin and eosin staining) and real-time RT-PCR analyses of macrophage (F4/80 and S100A9) and IL-6 gene expression. CR mice had lower body weight (20.3g +/– 0.2 vs. 26.0g +/– 0.5 (mean +/– SEM), p<0.05) and body adiposity (22.9% +/– 1.2 vs. 29% +/– 1.7, p<0.05) after 21 weeks on study compared to control mice. Additionally, CR mice had smaller tumors (100.3 mm^3 +/– 13.2 vs. 242.4 mm^3 +/– 28.3, p<0.05) relative to controls. Tumors from CR mice, relative to controls, exhibited a 3-fold decrease in F4/80 and S100A9 gene expression and a 2.5 fold decrease in IL-6 (p<0.05). Furthermore, HandE staining showed reduced macrophage infiltration in CR tumors compared to control tumors. These findings suggest that the inhibitory effects of CR on MC38 colon tumor growth are associated with reduced tumor infiltration of macrophages, which may lead to new targets for the prevention of colon cancer.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B54.

Abstract A55: Targeting of FXR and NHE-1 in prevention of esophageal adenocarcinoma

Zhang, G., Ye, F., Guan, B., Xu, X. — Thu, 07 Jan 2010 13:54:05 PST

The incidence of esophageal adenocarcinoma, as one of a few human cancers, has been increasing recently in the United States. Tobacco smoke and low fruit and vegetable consumption are risk factors for both esophageal squamous cell carcinoma and adenocarcinoma, whereas frequent gastroesophageal reflux, overweight, and obesity are linked to the increased incidence of esophageal adenocarcinoma. Our research objective is to understand the molecular mechanisms of esophageal carcinogenesis for developing strategies in its early detection and prevention. In our previous studies, we have associated some of these risk factors with altered gene expression in esophageal cancer. We found that benzo[a]pyrene diol epoxide (BPDE, a carcinogen present in tobacco smoke and environmental pollution) and bile acid (a tumor promoter in gastrointestinal cancer) suppressed expression of RAR-β2 and RRIG1, but induced EGFR, p-ERK, AP-1, and COX-2 expression in esophageal cancer cells. In this study, we have detected expression of FXR and NHE-1, a regulator of intracellular pH, in esophageal cancer tissue specimens and then determined effects of their inhibitors in suppressing growth of esophageal cancer cells. We found that expression of FXR and NHE-1 is increased in esophageal cancer compared to the normal tissues. We also found that inhibition of FXR and NHE-1 activity by using guggulsterone and amiloride can effectively suppress the tumor cell growth and gene expression. Further study will reveal the underlying molecular mechanisms and use FXR and NHE-1 expression as biomarkers for early detection or prognosis of esophageal cancer.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A55.

Abstract B56: Regulation of immune-related genes by integrin signaling affects the cancer cell proliferation and invasion

Park, M. Y., Lee, H. D., Jeon, O.-H., Kim, D.-S. — Thu, 07 Jan 2010 13:54:17 PST

Cytokines have been implicated in tumor proliferation and metastasis. Saxatillin, snake venom-derived disintegrin, is known to suppress tumor progression in vivo and in vitro but its correlation with cytokine's functions has not been known yet. We have investigated the role of immune-related genes in cancer cell proliferation and metastasis in human ovarian cancer cell (MDAH 2774). We demonstrate that saxatilin, an integrin antagonist, mitigated MDAH 2774 proliferation and invasion by reducing the level of TNF- induced matrix metalloproteinase-9 (MMP-9) and IL-8 expression in a dose-dependent manner. And Immunoblot assay of nuclear extracts of the cancer cells implicated that signal transducer and activator of transcription (STAT) is related in integrin signaling pathway. We also observed the activity of human glioma cell-invasion mediated by IL-8, as examined by a Boyden chamber assay, involved the mechanism of enhancing the actin stress fiber formation. IL-8 increased the phosphorylation of focal adhesion kinase (FAK), known to be the site of integrin clustering and nuclear translocation of STAT. We have shown here that interleukin-8 promotes the cancer proliferation and that mRNA levels of immune-related genes are regulated by disintegrin in human ovarian cancer cell line. These results demonstrate immune-related genes as a mediator of metastasis and proliferation and disintegrin would contribute in slowing of cancer development by regulating integrin signaling. (This work was supported by the Korea Science and Engineering Foundation (KOSEF) grant funded by the Korea Government (No.2009-0081759), KIST grant, and the Brain Korea 21 (BK21) program.)

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B56.

Abstract A57: High-dose resveratrol modulates drug and carcinogen metabolizing enzymes in a healthy volunteer study

Thu, 07 Jan 2010 13:54:05 PST

Purpose: Resveratrol (RES) or 3, 4', 5-trihydroxystilbene has been shown to inhibit carcinogenesis by affecting various molecular events in the initiation, promotion and progression stages. The cancer chemopreventive activity of RES has been demonstrated in vivo in a wide variety of tumors including skin, mammary, gastrointestinal, and liver cancer models. Modulation of Phase I and Phase II enzymes has been suggested to be one of the mechanisms responsible for the cancer preventive effect of RES. We conducted a clinical study to determine the effect of pharmacological doses of RES on drug and carcinogen metabolizing enzymes.

Methods: Forty-two healthy volunteers underwent baseline assessment of Phase I and Phase II enzymes. A cocktail of cytochrome P450 (CYP) metabolic probe drugs, including caffeine, dextromethorphan, losartan, and buspirone, were administered to assess the activity of CYP1A2, 2D6, 2C9, and 3A4, respectively. Blood and urine samples were collected for 8 hours after probe drug administration to determine parent probe drug and metabolite concentrations for measurements of CYP enzyme activities. Blood lymphocyte glutathione S-transferase (GST) activity and GST- level, and serum total and direct bilirubin, a surrogate for UDP-glucuronosyl transferase (UGT) 1A1 activity, were measured to assess Phase II enzymes. After the baseline evaluation, study participants took 1 gm of RES once daily for 4 wks. Enzyme assessment was repeated upon intervention completion.

Results: RES intervention was found to suppress the activity of CYP3A4, 2D6, and 2C9. The geometric mean change of the activity index of CPY3A4, 2D6, and 2C9 was 33% (p = 0.01), 70% (p = 0.01), and 171% (p < 0.0001), respectively. CYP1A2 activity was induced; the geometric mean change of the activity index was 16% (p = 0.005). The overall GST and UGT1A1 activity index were minimally affected by the intervention while an induction of GST- level (84%, p = 0.002) and UGT1A1 activity index (20%, p = 0.0089) was observed in individuals with baseline enzyme level/activity in the lowest tertile.

Conclusion: We conclude that high doses of RES administration may modulate enzyme systems involved in carcinogen activation and detoxification, which may be one mechanism by which RES inhibits carcinogenesis. However, high doses of RES administration may lead to clinically relevant metabolic drug interactions. Further clinical studies are needed to determine whether lower doses of RES could be used to achieve cancer preventive activities. (Supported by N01CN35158 from the National Cancer Institute, Division of Cancer Prevention)

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A57.

Abstract A58: Cul3-mediated Nrf2 ubiquitination and ARE activation are dependent on the partial molar volume at position 151 of Keap1

Eggler, A. L., Small, E., Hannink, M., Mesecar, A. D. — Thu, 07 Jan 2010 13:54:05 PST

Nrf2 is a transcription factor that activates transcription of a battery of cytoprotective genes by binding to the antioxidant response element (ARE). Nrf2 is repressed by the cysteine-rich Keap1 protein, which targets Nrf2 for ubiquitination and subsequent degradation by a Cul3-mediated ubiquitination complex. Several promising chemopreventive agents, including sulforaphane, activate Nrf2 in Keap1 C151-dependent manner. We find that modification of C151 of human Keap1 by mutation to a tryptophan relieves the repression by Keap1 and allows activation of the ARE by Nrf2. Keap1 C151W has a decreased affinity for Cul3, and can no longer serve to target Nrf2 for ubiquitination, though it retains its affinity for Nrf2. A series of 12 mutant Keap1 proteins, each containing a different residue at position 151, was constructed to explore the chemistry required for the effect. The series reveals that the extent to which Keap1 loses the ability to target Nrf2 for degradation, and hence the ability to repress ARE activation, correlates well with the partial molar volume of the residue. Other physico-chemical properties do not appear to contribute significantly to the effect. Based on this finding, a structural model of the Keap1-Cul3 binding interface was constructed to investigate the potential mechanism of action of a tryptophan or other group at position 151. Several residues surrounding position 151, K131, R135 and K150, were observed in the model to be close enough to be involved in a steric clash with the tryptophan. Keap1 proteins containing these residues mutated to alanine, along with C151W, were evaluated for their ability to repress Nrf2. We find that none of mutations were able to restore the ability of Keap1 C151W to repress Nrf2. Additional residues are being investigated in effort to determine which residue(s) might be responsible for translating the increase in partial molar volume at position 151 to a lack of Nrf2 repression. This work has significant implications for how chemopreventive electrophiles that modify C151 disrupt the repressive function of Keap1.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A58.

Abstract B58: Gene expression study on a highly aggressive canine transmissible venereal tumor of a NOD/SCID mice model

Thu, 07 Jan 2010 13:54:17 PST

We have set up a xenograft NOD/SCID mice model bearing canine transmissible venereal tumor (CTVT) (designated as MCTVT). In addition to the similarity of the tumor cells between CTVT and MCTVT, the insertion of the specific gene fragment in the 5' end of c-myc characteristic for a CTVT cell was also confirmed in MCTVT. However, as inoculating back to dogs, the MCTVT showed a much more aggressive growth and much higher metastatic frequency than a common CTVT. The goal of this research was to explore the gene expression differences between CTVT and MCTVT, and tried to delineate the mechanisms of their growth pattern differences. The differential gene expressions between the 2 tumors were studied using Affymetrix. Studied by hierarchical analysis and filtering the differential expressed genes by 2-fold method, we have found 105 genes significantly up-regulated and 37 down-regulated in MCTVT comparing to CTVT. Many of these genes were previously published to be involved in the areas such as malignant candidate genes, important biological processes, tumor development and immune modulation. We then used Real-Time RT-PCR to study the top 30 up-regulated genes. Three genes (APOC1, MMP1 and KMO) were further confirmed that were significantly up-regulated in MCTVT. The three genes were then tested in 22 spontaneous canine mammary gland tumors (CMGT) using Real-Time RT-PCR, the results indicated that two out of the three up-regulated genes discriminated malignant from benign CMGT and their gene expression was significantly higher in grades 4 and 5 malignant CMGT than those from lower grade tumors. We are currently studying the activities of KMO in association with the tumor cell growth. This study presented the novel candidate gene (KMO) that might associate with the malignant growth of tumor cells and has potential to be used as a biological marker to differentiate degrees of malignancy.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B58.

Abstract A59: Xanthohumol from hops (Humulus lupulus L.) generates superoxide anion radicals via a mitochondria-mediated mechanism

Strathmann, J., Klimo, K., Sauer, S., Okun, J., Prehn, J., Gerhauser, C. — Thu, 07 Jan 2010 13:54:05 PST

Xanthohumol (XN), a polyphenol from hops (Humulus lupulus L.), exerts a broad spectrum of cancer chemopreventive activities, including the induction of apoptosis in human cancer cell lines. We speculated that apoptosis induction involved pro-oxidant effects at the mitochondrial membrane, leading to uncoupling of the respiratory chain and subsequent membrane collapse. Here, we investigated whether XN has potential to induce reactive oxygen species (ROS). By co-treatment of benign prostate hyperplasia cells (BPH-1) with XN and dihydroethidium (DHE), specifically oxidized by superoxide anion radicals (O₂^-*), we measured an immediate dose- and time-dependent increase in fluorescence, whereas Amplex Red, specific for hydrogen peroxide (H₂O₂), was not oxidized, indicating the formation of O₂^-*. O₂^-* formation was significantly inhibited by co-treatment with the anti-oxidants ascorbic acid and N-acetyl cysteine or the superoxide dismutase mimetic MnTMPyP. Fluorescence microscopy images of BPH-1 stained with MitoSOX Red, specific for mitochondrial O₂^-*, suggested a mitochodrial origin of O₂^-* formation, which was confirmed by XN-mediated induction of O₂^-* in isolated mitochondria. Furthermore, in BPH-1-⁰ (rho-zero) cells, harboring non-functional mitochondria, XN-treatment did not induce O₂^-*. As one mechanism of XN-mediated O₂^-* formation, we hypothesize that XN is oxidized to its respective phenoxylradical by intracellular oxidases in the presence of glutathione (GSH) and traces of H₂O₂, which produces O₂^-* as side poduct. This was supported by the finding that inhibition of oxidases with diphenylene iodonium (DPI) significantly inhibited XN-induced O₂^-* formation. Additionally, we demonstrated a time- and dose-dependent increase in oxidized glutathione (GSSG) and global GSH depletion upon XN-treatment. Strikingly, within 15min after XN treatment, intracellular ATP production was reduced by 94% and we observed direct inhibition of complexes I – III of the respiratory chain in submitochondrial particles from bovine heart, as well as in BPH-1. In parallel, the mitochondrial membrane potential broke down already after 10min of XN-treatment and as a consequence, release of cytochrome c was observed, leading to the induction of apoptosis.

In this study, we demonstrate cancer chemopreventive activity of XN by the induction of O₂^-*, which disrupts the cellular redox balance and mitochondrial integrity and subsequently triggers cancer cells into apoptosis.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A59.

Abstract B59: Induction of TXNIP in response to metabolic changes associated with loss of p53

Wheatley, K., Nogueira, L., Perkins, S. N., Hursting, S. D. — Thu, 07 Jan 2010 13:54:17 PST

The understanding of the function of p53 has expanded beyond its role as a master cell cycle regulator. Recent findings connect p53 to cellular metabolism in that it suppresses anaerobic metabolism, the preferred mode of ATP production of most transformed cells. Interestingly, the p53-inducible genes that modulate metabolism also alter production or scavenging of reactive oxygen species (ROS). To better understand the metabolic changes that occur in response to p53-deficiency, we compared the expression of genes related to oxidative stress in the mammary fat pad of p53 +/+ and p53 +/– female mice. From a qPCR array that measured the expression of 85 genes, thioredoxin-interacting protein (TXNIP) levels were markedly increased in the p53 +/– mice compared to p53 +/+ mice (n = 3/group). This gene is of particular interest because TXNIP expression is increased by glucose flux and binds reduced thioredoxin, resulting in accumulation of ROS which has been shown to activate p53. To validate this finding, qPCR was performed (n=6/group) and TXNIP mRNA expression was increased 2.6 ± 0.2 fold (p < 0.001) in the mammary fat pad of p53 +/– mice compared to p53 +/+ mice. Importantly, the p53 +/– mice exhibited significantly lower fasting glucose levels than 53 +/+ mice (104.2 ± 7.0 versus 128.5 ± 3.1 mg/dL, p <0.01). We hypothesized that induction of TXNIP is in response to metabolic changes occurring with loss of p53. Using siRNA to knockdown p53, we tested this hypothesis and found that TXNIP mRNA expression increased 2.4 ± 0.3 fold (p < 0.01) 72 hours after p53 knockdown compared to control cells receiving scrambled siRNA. Furthermore, this increase was preceded by a spike in glucose consumption and lactate production. From these data, we conclude that TXNIP, in the absence of p53, is responding to changes in cellular metabolism. Current experiments are aimed at determining the effect of TXNIP induction in MCF7 cells on proliferation and glucose metabolism.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B59.

Abstract A60: Epigenetic modifications of huntingtin-related genes by dietary components for the prevention and treatment of breast cancer

Abdolmaleky, S. H., Eskandari, M., Li, L., Zhou, J.-R. — Thu, 07 Jan 2010 13:54:05 PST

Huntingtin protein (Htt) interplays with a large numbers of proteins and participates in diverse cellular pathways. Wide variety of Htt binding partners have been identified, including the Htt-Interacting protein-1 (HIP1) and Htt-associated protein-1 (HAP1). Htt has been shown pro-apoptotic activity, and malfunctioning of Htt may result in cell outgrowth. HIP1 is involved in endocytosis and receptor trafficking and introduced as an oncoprotein. An altered expression of HIP1 has been reported in various cancers including breast cancer. HAP1 maintains the normal level of membrane TrkA by preventing the degradation of internalized TrkA. Recent evidence supports a role of HAP1 in micro-tubule-dependent organells transport, but its role in cancer development and progression has not been studied. We propose that the HAP1 and HIP1 may serve as a pair of "Ying-Yang" modulators on the Htt functions and that the Htt-HAP1-HIP1 pathway may play an important role in the development and progression of breast cancer. We further propose that dietary/nutritional components that target this pathway may have chemopreventive effects on breast cancer. The objective of this study was to evaluate the differential expression and epigenetic modification patterns of Htt pathway related genes in normal and cancerous breast cells treated by dietary active components.

Human breast cancer cells were treated with dietary components known to prevent cancer cell growth and the effects of these components on HAP1, HIP1 and HTT expressions and promoter DNA methylations were investigated by using real-time PCR, Methylation Specific PCR (MSP) and bisulfite sequencing. HAP1 gene was silenced in several breast cancer cell lines including MCF7, MDA-MB231, MB453, SKBR3 and in much lower extent in immortalized MCF10A cells, but not in normal human mammary epithelial cell line (HMEC). Epigenetic analysis for Htt, HIP1 and HAP1 showed severe HAP1 promoter DNA hypermethylation in breast cancer cell lines, but not in HMEC. When the cells were treated with 5-AZaC (a DNA demethylating agent) and butyrate (a HDAC inhibitor), we found that 5-AZaC treatment significantly increased HAP1 expression by over 100 times, but butyrate had little effects. Treatment of the cells with dietary active compounds, sulfuraphane, EGCG, oridonin, tanshinone 2A and cryptotanshinone increased expression of HAP1 and HTT genes and decreased expression of HIP1 gene in HMEC, more significantly in cancer cell lines MCF7 and MB453. Preliminary studies indicate that these dietary components acted through modulation of HAP1 promoter methylation and further experiments are taking place to construct HTT and HAP-1 expressing plasmids for further in vitro and in vivo gene function studies.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):A60.

Abstract B60: HPP1-mediated tumor suppression and interferon signaling

Hernandez, J. M., Elahi, A., Shibata, D. — Thu, 07 Jan 2010 13:54:17 PST

Interferon resistance is common to the majority of cancer cell lines and primary tumors, and confers increased tumorigenicity and evasion of immune surveillance. HPP1, a recently characterized tumor suppressor gene associated with STAT1 signaling, is silenced in the majority of colorectal neoplasms. We have sought to determine if HPP1's tumor suppressive effects are mediated by interferon-associated pathways and whether HPP1 is capable of restoring sensitivity to interferon. We have overexpressed HPP1 in the HCT 116 colorectal cancer cell line and, by microarray analysis, have demonstrated that ectopic expression of HPP1 resulted in a dramatic upregulation of STAT1 as well as a number of associated interferon-inducible genes. We have previously shown that downregulation of STAT1 by siRNA in HPP1 transfectants results in a restoration of growth potential. Given that STAT1 homodimers bind specifically to promoter GAS (gamma activating sites) sites causing transcriptional upregulation of target genes, we transfected luciferase GAS reporter (pLucGAS) and control plasmids into HPP1 and control transfectants. Overexpression of HPP1 was associated with a significant increase in GAS site binding (p=0.007), suggesting that HPP1 mediates tumor suppression via its association with Type II-like (gamma) interferon pathways. To investigate the importance of Type II-like pathways, we treated HCT 116 cells, with and without overexpression of HPP1, with increasing doses of interferon gamma. Induction of activated STAT1 (phosphoSTAT1), was demonstrable in HPP1-overexpressing transfectants with a progressive rise concordant with interferon dose escalation. Interferon gamma was unable to induce any augmentation of activated STAT1 in controls. Despite progressive induction of phosphoSTAT1, no significant alterations in proliferation, apoptosis or cell cycle distribution were observed with interferon gamma treatment of HPP1 transfectants. We conclude that activated STAT1 and Type II-like interferon-associated pathways are important in mediating the tumor suppressive effects of HPP1. The lack of additional anti-proliferative effects of interferon on HPP1 transfectants may be due to saturation of the pathway. However, further investigation of the role of other STAT1-associated mechanisms in HPP1 tumor suppression, such as the Type I-like interferon (alpha) pathway is warranted.

Citation Information: Cancer Prev Res 2010;3(1 Suppl):B60.