KDR and meningioma: Sunitinib, unlike the previous single-target therapies, is a small-molecule kinase that inhibits different targets, such as VEGFR, PDGFR, FMS-like tyrosine kinase, KIT, CSF1R (macrophage colony-stimulating factor-1 receptor) and RET (a proto-oncogene), and most of them are highly represented in meningiomas.