Abstract: 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 (P<0.05).
Down-regulation of miR-218 was found to correlate significantly with the tumor size (>5 cm) and an advanced TNM stage (III+
IV) (P<0.05). 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 (P<0.05). Conclusion The
low-expression 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.