HGF and central nervous system cancer: The process of vascularization of gliomas is complex and involves the participation of several factors, like Vascular Endothelial Growth Factor A (VEGFA), Angiopoietin 1/2 (ANG-1/2), Interleukin 8 (IL-8), PDGFA, Fibroblast Growth Factors (FGFs), Transforming Growth Factor Beta 1 (TGF-β1) and Hepatocyte Growth Factor (HGF) [7,106].