RESUMEN
<p><b>OBJECTIVE</b>To investigate the expression of microRNA-107 (miR-107) and its functional role in hepatocellular carcinoma(HCC).</p><p><b>METHODS</b>The gene chip data of HCC obtained from the Gene Expression Omnibus (GEO) database and the Cancer Genome Atlas (TCGA) database were used to analyze the expression levels of miR-107 in liver cancer. Twenty-two pairs of fresh surgical specimens of HCC and adjacent tissues and 53 paraffin-embedded specimens of HCC were examined for miR-107 expression by qRT-PCR. The correlation of the expression levels of miR-107 with the clinicopathologic characteristics of the patients were analyzed. The role of miR-107 in regulating the proliferation of hepatocellular carcinoma cells were determined by MTT assay in Huh7 cells transfected with a miR-107 mimic or inhibitor.</p><p><b>RESULTS</b>The expression levels of miR-107 were significantly up-regulated in HCC tissues as compared to the adjacent tissues (P<0.05) in positive correlation with the tumor size (P<0.032). Transfection with miR-107 mimics significantly promoted the cell proliferation (P<0.0001) while miR-107 inhibitor inhibited the cell proliferation (P<0.0001).</p><p><b>CONCLUSION</b>The expression of miR-107 is up- regulated in HCC tissues and its expression levels are correlated with HCC cell proliferation, suggesting its role as a potential oncogene in liver cancer.</p>