MicroRNA-23a induces apoptosis of hepatocarcinoma cell line MHCC97H via down-regulating KIAP: a mechanism study.

OBJECTIVE: Hepatocarcinoma is a great threat to global health. MicroRNA-23a was suggested to regulate growth and apoptosis in certain cell lines. Our study was focused on growth, proliferation, and apoptosis of hepatocarcinoma cell line MHCC97H under the influence of microRNA-23a, and explored the mechanism of pro-apoptosis microRNA-23a. MATERIALS AND METHODS: MicroRNA-23a and control microRNA (scramble miRNA, for short as miRNA) were synthesized with the routine protocol. Lipofection transfection was performed in hepatocarcinoma cell line MHCC97H. 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay, caspase-3 activity detection, and flow cytometry were performed to examine growth, proliferation, and apoptosis of hepatocarcinoma cell line MHCC97H, respectively. Kidney inhibitor of apoptosis protein (KIAP) and small interfere RNA (siRNA) was synthesized for inhibition of KIAP. KIAP plasmid was established for activation of KIAP. Western blot was performed to examine the protein expression of KIAP and caspase protein family after transfection of KIAP siRNA or KIAP plasmid. RESULTS: Compared with miRNA transfection, microRNA-23a transfection significantly reduced the growth of MHCC97H cells, and decreased the expression of KIAP (p < 0.05). Enhanced translocation of phosphatidylserine and activation of caspase-3 were observed in microRNA-23a transfection cells. Moreover, inhibition of KIAP enhanced the pro-apoptosis effect of microRNA-23a, while activation of KIAP abrogated pro-apoptosis effect of microRNA-23a. CONCLUSIONS: MicroRNA-23a inhibits growth and proliferation of MHCC97H cells, and induces apoptosis of MHCC97H cells via down-regulating KIAP. KIAP could be a potential therapeutic target for hepatocarcinoma treatment.