[MicroRNA-218 expression and its role in hepatocellular carcinoma].

Objective To investigate the expression of microRNA-218(miR-218) and its role in hepatocellular carcinoma(HCC).Methods Forty-six pairs of fresh surgical specimens of HCC and adjacent tissues were examined for miR-218 expression using qRT-PCR.A miR-218 mimic was transfected into HepG2 cells,and the cell viability and apoptosis were analyzed by MTT assay and flow cytometry,and the potential targets of miR-218 were detected by qRT-PCR and Western blotting.Results The expressions of miR-218 in HCC tissues were significantly down-regulated compared to those in the adjacent tissues(P0.05).Down-regulation of miR-218 was found to correlate significantly with the tumor size(5 cm) and an advanced TNM stage(III+ IV)(P0.05).Ectopic expression of miR-218 in HepG2 cells resulted in suppressed cell proliferation and enhanced cell apoptosis as well as the down-regulation of Bmi-1 and CDK6 mRNA and protein expressions(P0.05).Conclusion The lowexpression of miR-218 is correlated with malignant clinicopathological characteristics of HCC,and miR-218 may inhibit cell proliferation and promote cell apoptosis by down-regulating Bmi-1 and CDK6 in HCC.