Human equilibrative nucleoside transporter 1 (hENT1) protein is associated with short survival in resected ampullary cancer

Background: Gemcitabine is an acceptable alternative to best supportive care in the treatment of advanced biliarytract cancers. The human equilibrative nucleoside transporter 1 (hENT1) is a ubiquitous protein and is the major meansby which gemcitabine enters human cells. Moreover, recent reports indicate a significant correlation betweenimmunohistochemical variations of hENT1 in tumor samples and survival after gemcitabine therapy in patients withsolid tumors.Materials and methods: We used immunohistochemistry to assess the abundance and distribution of hENT1 intumor samples from radically resected cancer of the ampulla, and sought correlations between immunohistochemicalresults and clinical parameters including disease outcomes.Results: In the 41 individual tumors studied, 12 (29.3%) had uniformly high hENT1 immunostaining. Statisticalanalysis showed a significant correlation between hENT1 and Ki-67 (P = 0.04). No statistical significant differenceswere found between immunohistochemical findings and patient characteristics (sex, age, and tumor–node–metastasis). On univariate analysis, hENT1 and Ki-67 expression were associated with overall survival (OS).Specifically, those patients with overexpression of hENT1 showed a shorter OS (P = 0.022) and those with high Ki-67staining showed a shorter survival (P = 0.05).Conclusions: hENT1 expression is a molecular prognostic marker for patients with resected ampullary cancer andholds promise as a predictive factor to assist in chemotherapy decisions.