13 June 2014
Vol 344, Issue 6189

About The Cover

Cover image expansion

COVER Immunofluorescence microscopy image of squamous cell carcinoma (SCC). SCCs contain tumor-initiating stem cells and their early progeny, which, like normal cells, reside along the tumor-stroma interface and express high levels of integrins (white) and progenitor keratins (green). Stem cells with high tumor-initiating capacity are shown in red; nuclear DNA is in blue. Average cell size within the tumor, 10 micrometers. See page 1243 and
Image: Courtesy of Markus Schober and Elaine Fuchs [see Proc. Natl. Acad. Sci. U.S.A. 108, 10544–10549 (2011)]