Abstract: Objective  To investigate the effects of pioglitazone on the proliferation and apoptosis of human pancreatic cancer cell line PANC-1 and its molecular mechanism. Methods Human pancreatic cancer cell line PANC-1 was cultured in vitro，pioglitazone （0，10，20，50 μmol/L） or gemcitabine（50 μmol/L） was administered for 0 h，12 h，24 h，48 h　and 72 h，respectively. The proliferation of PANC-1 cells was at 0 h，12 h，24 h，48 h and 72 h detected by CCK-8 assay，cell cycle，and apoptosis were detected by flow cytometry at 72 h，4，6-diamidino-2-phenylindole（DAPI） staining was used to detect the morphological changes of apoptosis at 48 h，Western blot was used to detect apoptosis and the expression of MAPK/ERK signaling pathway-related proteins at 48 h. Results Compared with pioglitazone at 0 μmol/L，OD value of PANC-1 cells in 50 μmol/L gemcitabine，10，20 and 50 μmol/L pioglitazone groups at 24 h，48 h and 72 h decreased significantly（P<0.05），and the percentage of G0/G1 phase cells，the apoptotic rate，the expressions of Bax and caspase-3、p-ERK proteins increased significantly at 48 h（P<0.05），while the proportion of S phase cells，the expressions of Bcl-2 protein decreased significantly（P<0.05） at 48 h，the degree of cell shrinkage gradually increased，and the nucleus gradually fragmented. Compared with the 50 μmol/L gemcitabine group，the OD values of PANC-1 cells in the 10 μmol/L pioglitazone group was increased（Ｐ＜0.05），while the 50 μmol/L pioglitazone group was decreased at 24 h，48 h and 72 h（P<0.05）；the proportion of G0/G1 cells，the apoptotic rate，the expressions of Bax and caspase-3,p-ERK proteins were decreased（P<0.05），while the 50 μmol/L pioglitazone group was increased at 48 h（P<0.05）；the proportion of cells in S phase，the expressions of Bcl-2 protein were increased（P<0.05），while the 50 μmol/L pioglitazone group was decreased at 48 h（P<0.05）. Conclusions Pioglitazone can inhibit the proliferation and induce apoptosis of pancreatic cancer cell PANC-1，and it may be achieved by up-regulating the MAPK/ERK pathway.

Key words: Pancreatic cancer；Pioglitazone；Proliferation；Cycle；Apoptosis；PANC-1；MAPK/ERK pathway