TGFB1 and glioma: When exposed to the exosomes released by glioma cells, the expansion of BMDCs with MDSCs phenotype was induced in healthy BMDCs (Gielen et al., 2016; Guo et al., 2019), secreting IL-10, TGF-β, Fas-ligand and B7-H1 to inhibit the activation of T lymphocytes (Chae et al., 2015).