FLT1 and neoplasm: Sorafenib is a multitargeted and multikinase inhibitor that inhibits the growth and proliferation of tumor cells, as well as tumor angiogenesis by blocking its various targets, including Raf serine/threonine kinase, c-Kit, platelet-derived growth factor receptor β (PDGFR-β), and VEGFR (vascular endothelial growth factor receptor) 1–3.