Local and systemic metastasis of hepatocellular carcinoma (HCC) causes the poor prognosis and increasing evidence confirms that aberrant miRNAs were involved in cancer progression. However, the expression and mechanisms of a specific miR-3194-3p in HCC remains unknown. In this research, we demonstrated that miR-3194-3p, significantly down-regulated in HCC tissues and cell lines, was associated with metastasis and recurrence of HCC. Notably, gain- and loss-of-function assays demonstrated that miR-3194-3p inhibited the migration, invasion and epithelial-mesenchymal transition (EMT) of HCC cells in vitro and in vivo. BCL9, up-regulated in HCC tissues, was a direct downstream target of miR-3194-3p and mediated the functional influence of miR-3194-3p. Most importantly, miR-3194-3p exerted its function by regulating β-catenin pathway. Moreover, miR-3194-3p and BCL9 expression were markedly correlated with adverse clinical features and poor prognosis of HCC patients. We showed that hypoxia was responsible for the down-expression of miR-3194-3p in HCC. Also, the promoting effects of hypoxia on metastasis and EMT of HCC cells were reversed by miR-3194-3p. Altogether, our study suggested that miR-3194-3p inhibits HCC EMT via decreasing Wnt/β-catenin signaling through targeting BCL9 and might be a therapeutic target for HCC.
Keywords: BCL9; hepatocellular carcinoma; hypoxia; miR-3194-3p; β-catenin.