Objective To investigate the regulatory effect of somatostatin analogue (SMS201995,SMS) on proliferation and apoptosis in human cholangiocarcinoma cell line in vitro. MethodsProliferation curve, flow cytometry, agarose gel electrophoresis, Annexin VFITC and flow cytometric immunofluorescent technique were performed to identify the inhibitory effect on cell proliferation and the induction of apoptosis of human cholangiocarcinoma cells (SKChA1). ResultsSMS significantly reduced the SKChA1 cell growth by serum in long experiments and transiently accumulated it in G0/G1 phase. Dotplot analysis of cells duallabeled with Annexin VFITC and PI confirmed the induction of apoptosis by SMS in SKChA1 cells.AnnexinVFITC labeling was markedly enhanced following treatment with SMS for 24 h. DNA of treated SKChA1 cells appeared a ladder pattern characteristic of apoptosis. Besides, timedependent increase in bax and decrease in bcl2 occured during SMS treatment. Conclusion SMS could inhibit the proliferation activity and induce apoptosis of cholangiocarcinoma cell line SKChA1. The mechanisms of apoptosis might be correlated with the expression of apoptosisregulatory gene bax and bcl2.