RRM1 and pancreatic neoplasm: Since a potential prognostic role for hENT1 and for RRM1 has been postulated [9, 21], and increased hENT1 levels enhance the response to gemcitabine in human pancreatic cancer [19] and are associated with a longer survival [6, 22-24], we then assessed hENT1 protein expression in pancreatic cancer biopsies of the nude mice allocated in the four treatment groups.