MicroRNA-1908 functions as a glioblastoma oncogene by suppressing PTEN tumor suppressor pathway

BACKGROUND: We aimed to investigate whether miRNA-1908 is an oncogene in human glioblastoma and find the possible mechanism of miR-1908. METHODS: We investigated the growth potentials of miRNA-1908-overexpressing SW-1783 cells in vitro and in vivo. In order to identify the target molecule of miRNA-1908, a luciferase reporter assay was performed, and the corresponding downstream signaling pathway was examined using immunohistochemistry of human glioblastoma tissues. We also investigated the miRNA-1908 expression in 34 patients according to the postoperative risk of recurrence. RESULTS: The overexpression of miRNA-1908 significantly promoted anchorage-independent growth in vitro and significantly increased the tumor forming potential in vivo. MiRNA-1908 significantly suppressed the luciferase activity of mRNA combined with the PTEN 3’-UTR. Furthermore, the expression levels of miRNA-1908 were significantly increased in the patients with a high risk of recurrence compared to that observed in the low-risk patients, and this higher expression correlated with a poor survival. CONCLUSIONS: miRNA-1908 functions as an oncogene in glioblastoma by repressing the PTEN pathway. MiR-1908 is a potential new molecular marker for predicting the risk of recurrence and prognosis of glioblastoma. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12943-015-0423-0) contains supplementary material, which is available to authorized users.