Downregulation of miR-552 in hepatocellular carcinoma inhibits cell migration and invasion, and promotes cell apoptosis via RUNX3

Research conducted previously has indicated that microRNAs (miRs) have potential effects on the pathogenesis of hepatocellular carcinoma (HCC). The biological functions of miR-552 have been well documented in colon cancer; however, the role of miR-552 in HCC remains unclear. The present study evaluated the effects of miR-552 in HCC physiology, using HCC cell lines as model. An miR-552 inhibitor was transfected into HCC cell lines to knock down the expression of miR-552. Reverse transcription-quantitative PCR and western blot analysis were used to detect the expression of miR-552 and Runt-related transcription factor 3 (RUNX3), respectively. MTT assay was used to analyze cell viability, whilst Transwell and wound-healing assay were used to investigate cell migration. Flow cytometry was performed to measure cell apoptosis. The direct association between RUNX3 and miR-552 was evaluated using dual luciferase reporter assay. The expression of miR-552 was significantly elevated in HCC tumor tissues compared with the adjacent healthy samples. Additionally, transfection with the miR-552 inhibitor decreased cell viability and migration. miR-552 knockdown also increased HCC cell apoptosis in vitro. In conclusion, these results suggest that miR-552 has an oncogenic function in HCC and is a potential biomarker for detecting HCC.