Abstract: Objective To investigate the impact of 5-AZA on microRNA-34a/c (miR-34a and miR-34c) expression in human hepatocellular carcinoma (HCC) cells and to elucidate the molecular mechanism of 5-AZA for inhibiting glycolysis in HCC cells. Methods Real-time PCR analysis was conducted to determine the expression levels of miR-34a/c in HCC cells with 5-AZA treatment. The expression of specific genes related to glycolysis was evaluated by using Real-time PCR in HCC cells with miR-34 overexpression or 5-AZA treatment. The effect of miR-34a/c or 5-AZA treatment on the metabolic shift in HCC cells was explored by detecting the cellular lactate production and glucose consumption. Rescue assay was employed to investigate the correlation between 5-AZA, miR-34a/c, and the regulation of glycolysis in HCC cells. Results The expression of miR-34a/c is increased in 5-AZA-treated BEL7402 HCC cells (P<0.01). No significant change is observed in the expression of miR-34b in HCC cells with 5-AZA treatment. Enforced expression of miR-34a/c leads to reduced levels of LDH-A in BEL7402 HCC cells(P<0.05). Rescue assay reveals that inhibition of miR-34a/c to prevent 5-AZA induction results in suppressed glycolysis in BEL7402 HCC cells. Conclusion 5-AZA inhibits metabolic shift in HCC cells via inducing the expression of miR-34a/c.

Key words: Hypomethylating drugs, miR-34, HCC, Warburg effect