The cover features a three-color, fluorescence image of a human papillomavirus 16 (HPV16)positive human anal cancer stained with antibodies to p16 (red), a biomarker for HPV-positive cancers, and phosphorylated S6 (green), a marker for activated mammalian target of rapamycin (mTOR) pathway. Nuclei were counterstained with 4',6-diamidino-2-phenylindole (DAPI, blue). The individual color images (200X magnification) were taken using a Zeiss Apotome Fluorescent microscope and merged. This image relates to two articles by Stelzer et al. in this issue of the journal (beginning on page 1534 and page 1542) that describe mouse models for human anal cancer and their use in testing the activity of rapamycin.