Inhibition effect of miR-577 on hepatocellular carcinoma cell growth via targeting β-catenin

To investigate the expression and the regulation effect of cell growth of microRNA-577 in hepatocellular carcinoma (HCC).

qRT-PCR was applied to detect the relative expression of miR-577 in 70 paired HCC and matched tumor adjacent tissues collecting from resection between March 2011 and March 2014. Pearson chi-square test was used to analyze the relationship between the miR-577 expression and clinical features. The miR-577 mimics were transfected into HepG2 cells; cell cycles were detected by flow cytometry, cell proliferation was measured by MTT assay and BrdU incorporation assay, and cell apoptosis was determined by flow cytometry and caspase3/7 activity analysis. The expressions of β-catenin were measured by immunohistochemistry. Spearman correlation analysis was used to analyze the relationship between miR-577 and β-catenin. qRT-PCR and western-blot were used to detect the expression of β-catenin in transfected HepG2 cells.

The relative expressions of miR-577 was significantly lower in HCC tissues compared to the matched normal tumor-adjacent tissues (P < 0.05). Low expression of miR-577 was significantly associated with large tumor size (≥5 cm, P < 0.05) and advanced tumor node metastasis stage (III+IV, P < 0.05). Transfection of miR-577 mimics could inhibit repress cell proliferation, enhance cell apoptosis and block the cell cycles in G0/G1 phase (P < 0.05). miR-577 in HCC group had a significant negative correlation relationship with the expression of downstream target of β-catenin (P < 0.05). Both the mRNA and protein expression in HepG2 cells were down-regulated after transfection (P < 0.05).

Low expression of miR-577 is related to the malignant clinicopathological features in HCC tissues, and miR-577 may suppress HCC growth through down-regulating β-catenin.