It has been shown that GFAP+ and GLAST+ astrocytes, when transformed, give rise to GBM with different features: GFAP+ tumor cells are intrinsically more proliferative than GLAST-derived tumors that, instead, may rely more on the TME, as suggested by enhanced recruitment of non-malignant glial cells (Irvin et al., 2017). This evidence concerns the gene GFAP and glioblastoma.