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with differentiation of human colon cancer cells. Cancer Biol Ther 2010, 9:215–222. 45. Kemper K, Sprick M, de Bree M, Scopelliti A, Vermeulen L, Hoek M, et al.: The AC133 epitope, but not the CD133 protein, is lost upon cancer stem cell differentiation. Cancer Res 2010, 70:719–729.PubMedCrossRef 46. Yang K, Chen X, Zhang B, Yang C, Chen H, Chen Z, et al.: Is CD133 a biomarker for cancer stem cells of colorectal cancer and brain tumors? A meta-analysis. Int J Biol Markers 2011, 26:173–180.PubMedCrossRef Competing interests The authors declare that they have no competing interests. Authors’ contributions CC, AC, AS conceived the

study and participated in its coordination. CC, GFZ, MM, AS participated in protocol design. GFZ, SS, MM, LRB provided tissue samples. ET prepared the tissue slides. AB, EC performed the immunohistochemical assays. SS, MM, LRB PTK6 evaluated and scored the staining. CC, GR, GG provided clinical information. MM, AS performed statistical analyses and drafted the manuscript. All authors read and approved the manuscript.”
“Introduction Pancreatic cancer has the worst prognosis of all major cancers, with an overall 5-year survival rate of around 5% [1]. The current clinical standard of care for advanced pancreatic cancer is gemcitabine, a cytotoxic nucleoside analogue. Gemcitabine results in a tumor response rate of 12% and offers a median survival time of 5 months [2]. Unfortunately, this means that the best current treatment offers very modest benefits.