ACCELERATED DISCOVERY Antiangiogenic Activity of Prostate-Specific Antigen

specific antigen (PSA) is widely used as a screening tool for prostate cancer. However, PSA is not prostate specific, hav-ing been detected in breast, lung, and uterine cancers. In one study, patients whose breast tumors had higher levels of PSA had a better prognosis than patients whose tumors had lower PSA levels. To test the hypothesis that PSA may have anti-angiogenic properties, we evaluated the effects of PSA on endothelial cell proliferation, migration, and invasion, which are key steps in angiogenesis, the process by which tumors develop a blood supply. Methods: To assess the antiprolifer-ative effects of PSA, we treated bovine endothelial cells and human endothelial cell lines (HUVEC and HMVEC-d) with purified human PSA (0.1–10 µM) and then stimulated them with 10 ng/mL fibroblast growth factor-2 (FGF-2). Effects on FGF-2- or vascular endothelial growth factor (VEGF)