MiR-130b functions as a tumor promoter in glioma via regulation of ERK/MAPK pathway.

OBJECTIVE: To investigate the miR-130b expression in patients with glioma and to analyze its role and underlying molecular mechanism on the carcinogenesis.

PATIENTS AND METHODS: The expression levels of miR-130b were detected with quantitative Real-time PCR. The relationship between miR-130b expression and clinicopathologic characteristics were analyzed. MiR-130b inhibitor was transfected into glioma cell lines to investigate its role in HCC. MTT assays were conducted to explore the impact of miR-130b down-expression on the proliferation of human glioma cells. Cell cycle and cell apoptosis assays were performed using flow cytometry. Levels of ERK/MAPK pathway related proteins were evaluated by Western blotting. Data were analyzed using the 2-ΔΔCT method through student's t-test via the GraphPad Prism software (La Jolla, CA, USA).

RESULTS: The expression of miR-130b was markedly upregulated in glioma cell lines and tissues, and high miR-130b expression was significantly associated with advanced WHO grade (p = 0.022) and low Karnofsky performance score (p = 0.001). In addition, downregulation of miR-130b inhibited the proliferation of glioma cells and induced cell-cycle arrest and cells apoptosis in vivo. Importantly, ERK/MAPK pathway was found to be inactivated in the glioma cell lines after miR-130b knockout experiment.

CONCLUSIONS: The current data indicated that miR-130b may play a critical role in the progression of glioma via ERK/MAPK signaling cascades, suggesting that it may be a useful therapeutic agent in glioma patients.