In conclusion, our results indicate that brain pericytes show an immunosuppressive function as a consequence of their interaction with GBM cells, possibly assisting the tumor immune evasion and, consequently promoting GBM tumor. This finding identify pericytes as key cellular components of the GBM niche, which should lead to further studies to search for possible ways to regulate their interaction with GBM cells to modulate their immunosuppressive function and control tumor growth.