KDR and neoplasm: This synergistic activity exhibited by anti-EGFR/VEGFR2 is most likely via its direct inhibition of EGFR and VEGFR2 signaling pathways of tumor cells or block autocrine mechanism since MDA-MD-231 cells secret VEGF and ramucirumab does not bind to mouse VEGFR2 to interfere angiogenic activity toward tumors.