KDR and cancer: VEGF binds to VEGFR, activating the downstream signaling pathways which promotes the process of endothelial cells proliferation, migration and neovascularization.[40–42] It has been demonstrated that angiogenesis is a main prerequisite factor and facilitator for tumor growth and metastasis.[43] In the light of these mechanisms, medicines and other therapeutic strategies targeting VEGF pathways to block normal angiogenesis have proven to be reasonably effective treatments for advanced cancers.