VEGFA and glioblastoma: Moreover, this tumor growth increases the amount of O2 and nutrients required, inducing the overexpression of VEGF and the angiogenesis in hypoxic areas.[4] GBM is known to be one of most vascularized tumors, due to the growth of abnormal lymphatic vasculature presenting abnormal endothelial hyperplasia, pinocytic vesicles, fenestration, and opening or loss of tight junctions between endothelial cells.[4,45] While these changes increase the permeability of the BBTB, the specificity of the glioma and the cranial microenvironment makes malignant gliomas less permeable.[26,46]