miR-486 regulates metastasis and chemosensitivity in hepatocellular carcinoma by targeting CLDN10 and CITRON.

AIM: miRNA-486 (miR-486) was first identified from the human fetal liver cDNA library and considered to be associated with hepatocellular carcinoma (HCC) development. Its roles in regulation of HCC metastasis and chemosensitivity have not been explored yet. METHODS: miR-486 expression in HCC tissues, cell lines and serum was evaluated by real-time polymerase chain reaction. miR-486 overexpression or downregulation in the cell lines SMMC-7721/LM3 was conducted by lentivirus transfection. Cell proliferation, migration and apoptosis were quantitated using commercial assays. Matrix metalloproteinase activity was quantitated by gelatin zymography. The target genes of miR-486 were screened by 3'-untranslated region luciferase report assays and their function was validated by small RNA interference. RESULTS: We show here that miR-486 is frequently down-expressed in HCC tissues and cell lines. Lentivirus-mediated restoration of miR-486 in HCC cell lines resulted in significant reduction in the ability of cell growth, colony formation and migration. However, miR-486 inhibition enhances proliferation and invasion of HCC cells. Two genes, CITRON and CLDN10 which regulate cell proliferation and invasion, respectively, were identified as the direct targets of miR-486 in HCC cells. CITRON and CLDN10 knockdown by siRNA results in similar phenotypes of miR-486 restoration in HCC cell lines. In addition, miR-486 enhances the chemosensitivity of HCC cells to sorafenib. CONCLUSION: Our data indicated that miR-486 may function as a novel tumor suppressor in HCC.