Add to ORKGPurpose: Vascular endothelial growth factor (VEGF) and its receptor, fetal liver kinase 1 (Flk-1), play an important role in vascular permeability and tumor angiogenesis. The aim of this study is to evaluate the therapeutic efficacy of 131I labeled anti-Flk-1 monoclonal antibody (DC101) on the growth of melanoma tumor, which is known to be very aggressive in vivo. Materials and Methods: Balb/c nude mice were injected subcutaneously with melanoma cells in the right flank. Tumors were allowed to grow up to 200-250 mm3 in volume. Gamma camera imaging and biodistribution studies were performed to identify an uptake of 131I-DC101 in various organs. Mice with tumor were randomly divided into five groups (10 mice per group) and injected intravenou...