KDR and neoplasm: This angiokinase inhibitor potently disrupts intracellular signaling pathways mediated by members of the vascular endothelial growth factor receptor (VEGFR), platelet-derived growth factor receptor (PDGFR), and fibroblast growth factor receptor (FGFR) families, which are key regulators of tumor angiogenesis and vascular integrity [54,55].