Low SIRT3 expression contributes to tumor progression, development and poor prognosis in human pancreatic carcinoma.

SIRT3, an important mitochondrial protein, may act as either an oncogene or tumor suppressor depending on the tumor-type. The aim of this study was to investigate the expression of SIRT3 in pancreatic carcinoma (PC) and its clinical association in PC patients. Immunohistochemistry was adopted to investigate the expression of SIRT3 in cancer and corrresponding adjacent non-cancer tissues across 79 patients with PC. The log-rank test and Cox hazard model were used to estimate the relationship between SIRT3 expression and prognosis. The staining results revealed that SIRT3 negative expression was more common in cancer tissues than in adjacent non-cancer tissues (P<0.001). Chi-square tests indicated that the expression of SIRT3 correlated with T status (p<0.001) and tumor stage (p=0.013). Kaplan-Meier analysis showed that negative SIRT3 expression is linked to a poor prognosis in PC patients. Multivariate analysis identified SIRT3 expression as an independent predictor for PC outcome both in the whole cohort and several subgroups of PC patients. Our results indicate that down-regulated SIRT3 may contribute to tumor progression and gloomy prognosis in PC patients and may sever as a novel prognostic marker.