KDR and cancer: Other approved anti-angiogenic antibody therapeutics including bevacizumab, an antagonist of the VEGF ligand (VEGF-A: Avastin®), and ramucirumab, an antagonist of the VEGF receptor (VEGFR-2: Cyramza®), are generally used in a combination regimen with chemotherapy to treat cancer patients, providing more efficacious therapeutic options for cancer patients [3,30].