Abstract
MicroRNAs and cancer stem cells have emerged as critical players in glioblastoma, one of the deadliest human cancers. In this study, we investigated the expression and function of microRNA-10b in glioblastoma cells and stem cells. An analysis of The Cancer Genome Atlas data revealed a correlation between high miR-10b levels and poor prognosis in glioblastoma patients. We measured the levels of miR-10b and found that it is upregulated in human glioblastoma tissues, glioblastoma cell and stem cell lines as compared to normal human tissues or astrocytes. Inhibition of miR-10b with a specific antagomir inhibited the proliferation of glioblastoma established and stem cell lines. Inhibition of miR-10b strongly reduced cell invasion and migration in glioblastoma cell and stem cell lines while overexpression of miR-10b induced cell migration and invasion. We also investigated several predicted targets of miR-10b but could not verify any of them experimentally. Additionally, miR-10b inhibition significantly decreased the in vivo growth of stem cell-derived orthotopic GBM xenografts. Altogether, our findings confirm the oncogenic effects of miR-10b in GBM cells and show for the first time a role of this microRNA in GBM stem cells. Targeting miR-10b might therefore inhibit glioblastoma stem cells, which are thought to be at the origin of glioblastoma and to contribute its recurrence and resistance to therapy.