KDR and neoplasm: Binding of VEGFA to VEGFR2 triggers a cascade of phosphorylation events, activating downstream PI3K/AKT and rapidly accelerated fibrosarcoma/mitogen-activated protein kinase (RAF/MAPK) pathways, thereby stimulating endothelial cell proliferation and migration, crucial for the formation of new vascular branches necessary for tumor growth and metastasis [147].