Apatinib is an oral-administered vascular endothelial growth factor receptor 2 (VEGFR-2) tyrosine kinase inhibitor (TKI)-based anti-cancer agent, whose antitumor activity is primarily achieved through inhibiting VEGFR-2-mediated angiogenesis to block tumor blood supply and induce tumor cell apoptosis (96). This evidence concerns the gene KDR and cancer.