Low MiR-149 expression is associated with unfavorable prognosis and enhanced Akt/mTOR signaling in glioma.

MicroRNAs (miRs) play critical roles in the progression of glioma. Previous in vitro studies have described the anti-tumor role of miR-149 in cancer cells including glioma. In this study, we aimed to investigate whether miR-149 is associated with the prognosis of glioma patients. A total of 163 glioma patients who underwent tumor resection were included in our follow-up study. We found that the miR-149 expression was significantly lower in tumor tissues compared with that in normal tissues (P<0.05). Kaplan-Meier and analysis showed that the miR-149 expression status was significantly associated with the survival duration (logrank test, P<0.001), and multivariate Cox regression revealed that patients with low miR-149 expression were exposed to a 1.825 fold higher death risk (HR=1.825, 95% CI=1.031-3.229, P=0.039) compared with those with high miR-149 expression. Further study showed that Akt/mTOR signaling was hyperactive in low miR-149 expressing tissues. Our study thus demonstrates that miR-149 expression in glioma tissues is critically associated with the prognosis of patients, suggesting its potential clinical significance.