MiR-32 induces cell proliferation, migration, and invasion in hepatocellular carcinoma by targeting PTEN.

MicroRNAs (miRNAs) regulate gene expression by inhibiting translation of target messenger RNAs (mRNAs) through pairing with miRNA recognition elements (MREs), usually in 3'-UTRs. miRNAs are involved in the pathogenesis of several types of cancers. Specifically, microRNA-32 (miR-32) is overexpressed in colorectal carcinoma, wherein accumulating evidence indicates that it functions as an oncogene. However, the function of miR-32 in hepatocellular carcinoma (HCC) has not been totally elucidated. In the present study, we found the expression of miR-32 was up-regulated in HCC tissue and cell lines, inversely the expression of phosphatase and tensin homolog (PTEN) decreased. Besides, miRNA-32 down-regulates PTEN through binding to 3'-UTR of PTEN mRNA from luciferase reporter assay, and the expression level of miR-32 could affect the proliferation, migration, and invasion of liver cancer cell lines via PTEN/Akt signaling pathway. Down-expression of PTEN could significantly attenuate the inhibitory effects of knockdown miR-32 on the proliferation, migration, and invasion of liver cancer cells, suggesting that miR-32 could be a potential target for HCC treatment.