miR-300 regulates tumor proliferation and metastasis by targeting lymphoid enhancer-binding factor 1 in hepatocellular carcinoma

Accumulating evidence indicates that microRNAs (miRNAs) have a critical role in cell proliferation and metastasis in hepatocellular carcinoma (HCC). However, the effect of miR-300 on the development and progression of HCC remains unclear. In the present study, it was observed that miRNA (miR)-300 expression was significantly decreased in HCC cell lines compared with normal liver cells. Furthermore, we detected the effects of miR-300 on cell proliferation and apoptosis, cell cycle, migration and invasion by using MTT, colony formation assay, wound healing, Transwell assay and flow cytometry methods, respectively. The results demonstrated that miR-300 overexpression inhibited proliferation, induced apoptosis and G1/S cell cycle arrest, and suppressed migration and invasion in Huh-7 cells, whereas miR-300 silencing promoted the proliferation, migration and invasion of Hep3B cells. Mechanistically, the transcription factor lymphoid enhancer-binding factor 1 (LEF-1), which was verified as a direct target gene of miR-300, promoted cell proliferation, migration and invasion and mediates the effects of miR-300 on HCC cells. In addition, low expression of miR-300 and high expression of LEF-1 in HCC tissues were found to be associated with poor prognosis of patients with HCC. These findings indicate that miR-300 may be a potential prognostic predictor and therapeutic target for patients with HCC.