Secretion of EVs-mediated miRNA-21 transfer by glioma cells triggers the downregulation of particular mRNA targets in microglia, reprogramming microglia, with more prominent alterations in Btg2, thereby reducing cell cycle protein D1 activity to negatively regulate cell proliferation, leading to enhanced proliferation of microglia and tumor cells and promoting glioma progression (181). Here, BTG2 is linked to central nervous system cancer.