mir-637 inhibits the proliferation of cholangiocarcinoma cell QBC939 through interfering CTSB expression.

OBJECTIVE: To investigate the role of mir-637 on the proliferation, migration and apoptosis in human cholangiocarcinoma (CCA) cell line QBC939, and the impact of mir-637 on Cathepsin B (CTSB) expression.

MATERIALS AND METHODS: Expression of mir-637 and CTSB in CCA tissues and adjacent non-tumor tissues were measured by Real-time PCR. CTSB expression in human CCA cell lines was detected with or without mir-637 exogenous overexpression through fluorescent quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) method. The efficiency of lentivirus-mir-637 vector infection, and the effect of mir-637 on the proliferation, migration ability, apoptosis and cell cycle of CCA cell were detected, respectively. The possibility of mir-637 targeting CTSB was also tested by bioinformatics method, correlation analysis and molecular biology method.

RESULTS: Decreased mir-637 and increased CTSB expression were observed in CCA tissue compared with adjacent non-tumor tissues. CTSB expression in mir-637 exogenously overexpressed QBC939 cells decreased compared with negative control. Mir-637 overexpression caused significant decrease of proliferation and migration ability of QBC939 cell. In addition, mir-637 overexpression induced that the cell cycle was blocked in G0/G1 phase, and cell apoptosis rate increased significantly.

CONCLUSIONS: mir-637 and CTSB play an important role in the proliferation and migration of CCA cells. Mir-637 could inhibit CTSB expression significantly, which in-turn down-regulates the proliferation, migration and invasion ability of QBC939 cell, and promotes apoptosis in QBC939 cell line.