MAP2K7 and glioblastoma: In our study, the treatment of Wortmannin also significantly inhibited the activation of MEK-ERK pathway that is induced by U87-EVs (Additional file 1: Fig. S8), suggesting that MEK-ERK pathway may act as a downstream factor of PI3K-Akt pathway and both pathways may work together in mediating the tumorigenic effects of glioblastoma-derived EVs.