MiR-145 reduces ADAM17 expression and inhibits in vitro migration and invasion of glioma cells

MicroRNAs are important regulators of gene expression and have been suggested to play a key role in tumorigenesis. In this study, we show that miR-145 is significantly downregulated in glioma cell lines compared to normal brain tissue and negatively regulates tumorigenesis. Restoration of miR-145 in glioma cells significantly reduced in vitro proliferation, migration and invasion. Also, overexpression of miR-145 reduced ADAM17 and EGFR expression. In addition, we tested the hypothesis that the miR-145-mediated suppression of cell proliferation, migration and invasion is, at least in part, due to silencing of ADAM17 and EGFR gene expression. Using luciferase reporters carrying the 3′-untranslated region of ADAM17 combined with western blotting, we identified ADAM17 as a direct target of miR-145. Collectively, these results suggest that as a tumor suppressor, miR-145 inhibits not only tumor proliferation, but also cell migration and invasion, and warrants further investigation.