P53-induced microRNA-107 inhibits proliferation of glioma cells and down-regulates the expression of CDK6 and Notch-2

MicroRNAs (miRNAs) are small noncoding RNAs that function as tumor suppressors or oncogenes. MicroRNA-107 (miR-107), a transcriptional target of p53, is deregulated in many cancer cell lines. Here, we showed that miR-107 is down-regulated in glioma tissues and cell lines, in particular, p53-mutated U251 and A172. Transfection of wild-type p53 into these cells stimulated miR-107 expression. To investigate the role of miR-107 in tumorigenesis, we constructed a lentiviral vector overexpressing miR-107. Notably, miR-107 inhibited proliferation and arrested the cell cycle at the G0-G1 phase in glioma cells. Transduction of Lenti-GFP-miR-107 into glioma cells inhibited CDK6 and Notch-2 protein expression. Our findings collectively demonstrate that p53-induced miR-107 suppresses brain tumor cell growth and down-regulates CDK6 and Notch-2 expression, supporting its tumor suppressor role and utility as a target for glioma therapy. (C) 2012 Elsevier Ireland Ltd. All rights reserved.