microRNAs (miRNAs) have been widely recognized as crucial regulators for tumorigenesis. However, the role of miR-632 in hepatocellular carcinoma (HCC) remains largely unknown. miR-632 expression in HCC cell lines was determined by quantitative real-time polymerase chain reaction. The role of miR-632 expression on overall survival of HCC patients was examined on the Kaplan-Meier plotter Web site. The dual luciferase reporter method was performed to investigate whether myc target 1 (MYCT1) was a target of miR-632. Cell counting kit-8 assay, colony formation assay, and Transwell invasion assay were performed to examine cell proliferation, colony formation, and cell invasion of HCC cells. The results showed miR-632 expression was elevated in HCC cell lines compared to normal cell lines. Loss-of-function experiments demonstrated that miR-632 downregulation was able to inhibit HCC cell proliferation, colony formation, and cell invasion. Moreover, miR-632 could negatively regulate the expression of MYCT1 in HCC cells. Importantly, the study showed miR-632 and MYCT1 were negatively correlated by analyzing the public data sets obtained from the Gene Expression Omnibus. Knockdown of MYCT1 by small interfering RNA partially reversed the effects of miR-632 on HCC cell events. The present study suggests that miR-632 regulates growth and invasion of HCC cells through targeting MYCT1.
Keywords: MYCT1; hepatocellular carcinoma; miR-632; oncogene; prognosis.