miR-154 targeting ZEB2 in hepatocellular carcinoma functions as a potential tumor suppressor

MicroRNA-154 (miR-154) has been identified as a tumor suppressor in several types of human cancers; however, its clinical significance and function in human hepatocellular carcinoma (HCC) remain unclear. The aim of the present study was to analyze the clinical significance and cellular function of miR-154 in HCC patients. The data showed that miR-154 expression was consistently lower in HCC tissues and cell lines compared to that in matched tumor-adjacent tissues and a normal hepatic cell line, and its expression was negatively correlated with tumor differentiation (P<0.01), TNM stage (P<0.01) and lymph node metastasis (P<0.01). Restoration of miR-154 expression in HepG2 cells inhibited cell proliferation, migration and invasion, and induced apoptosis and cell arrest at the G1 phase in vitro, as well as suppressed tumor growth in a nude mouse model. Using a luciferase assay, we identified that miR-154 was able to target the 3'-untranslated region (3'UTR) of ZEB2 mRNA. Then, we revealed that miR-154 was able to reduce ZEB2 expression at the levels of mRNA and protein using qRT-PCR and western blot analysis. Notably, restoration of expression of ZEB2 weakened miR-154-mediated suppression of tumor progression. In conclusion, these results indicate that miR-154 functions as a tumor suppressor in HCC by suppressing ZEB2, suggesting that miR-154 may serve as a potential target for HCC.