KDR and neoplasm: As one of the blood vessel growth factors and a key regulator in the development of tumor, vascular endothelial growth factor (VEGF) and VEGF receptor (VEGFR) pathway in tumor angiogenesis has attracted the interest of researchers in the field of cancer research and therapy.16–18 VEGF is mainly concentrated around the tumor vessels, and the response of tumor vessels to VEGF is higher than that of normal vessels, suggesting that VEGF is closely related to tumor angiogenesis.