Effect of MicroRNA-340 on Proliferation and Apoptosis of Hepatocellular Carcinoma Cell Lines

Objective To explore the effect of miR-340 overexpression on cell proliferation, cell cycle and apoptosis of human hepatocellular carcinoma HepG2 and MHCC-97L cells.

Methods The miR-340 mimic was transiently transfected into HCC cells using Lipofectamine^TM 2000 reagent. The mRNA level of miR-340 in HCC cell lines was determined by RT-PCR. Cell proliferation was detected by Brdu-ELISA kit. Flow cytometry was used to analyze cell cycle. Apoptosis was analyzed by Annexin V-FITC apoptosis detection kit.

Results The expression of miR-340 was decreased in HepG2 and MHCC-97L cells (P < 0.05); miR-340 overexpression significantly inhibited cell survival rate (P < 0.05); the percentage of cells in G₀/G₁ stage was increased and that in the S stage was reduced (both P < 0.05); miR-340 overexpression promoted the apoptosis of HepG2 and MHCC-97L cells also.

Conclusion miR-340 plays an important role in the inhibition of cell proliferation and the apoptosis induced by NF-κB1 down-regulation, suggesting that reduced miR-340 expression is one of the mechanisms of hepatocellular carcinogenesis.