MicroRNA-141 inhibits glioma cells growth and metastasis by targeting TGF-β2.

MicroRNA-141 (miR-141) has been reported to function as tumor suppressor in many types of cancer. However, the molecular function and underlying mechanisms of miR-141 in glioma is still unknown. The aims of this study were to investigate miR-141 expression and determine its biological function and underlying mechanism in glioma. In this study, we found that miR-141 expression levels, both in glioma cell lines and in tissues, were significantly lower than that in a normal human astrocyte cell line or adjacent non-cancerous tissues. Overexpression of miR-141 significantly inhibited glioma cell proliferation, colony formation, migration and invasion in vitro, as well as suppressed glioma tumor growth in vivo. In addition, transforming growth factor beta 2 (TGF-β2) was identified as a target of miR-141 in glioma cells. TGF-β2 expression was also found to be upregulated, and negatively associated with miR-141 in glioma tissues. TGF-β2 over-expression partly reversed the effect caused by transfection of miR-141 mimic. These findings together suggested that miR-141 functioned as tumor suppressor by targeting TGF-β2, and that miR-141 might be a promising therapeutic strategy for future treatment of glioma.