An isolated antibody or an antigen-binding fragment thereof having a specific binding affinity to an epitope located within the domain 1 or domain 3 of human vascular endothelial growth factor receptor 2 (VEGFR2 SEQ ID NO: 74) is disclosed. The epitope within the domain 3 of the VEGFR2 is located between amino acid residues 250 and 270 of SEQ ID NO: 74. Use of the antibody or antigen-binding fragment thereof in the manufacture of a medicament for inhibiting tumor growth, tumor angiogenesis, and/or inducing cancer cell cytotoxicity in a subject in need thereof is also disclosed. Also disclosed is a method of detecting the presence of VEGFR2 in a tumor vascular endothelial cell or a cancer cell in a biological sample.本發明揭露一種分離的抗體或其抗原結合片段,其對位於人類血管內皮生長因子受體2(VEGFR2;SEQ ID NO:74)之結構域1或結構域3內的抗原決定位具有特異性結合親和力。VEGFR2之結構域3內的抗原決定位係位於SEQ ID NO:74之第250個胺基酸殘基和第270個胺基酸殘基之間。本發明還揭露此抗體或其抗原結合片段用於製造在有此需要的個體中用以抑制腫瘤生長、腫瘤血管新生和/或誘導癌細胞之細胞毒性的藥物的用途。另外,本發明還揭露一種偵測生物樣品中位在腫瘤血管內皮細胞或癌細胞上VEGFR2存在的方法。
