PDGFRB and neoplasm: Sorafenib works primarily on two resistance pathways: it can directly inhibit tumor cell proliferation through Ras/Raf/MEK/ERK, PI3K/Akt, and JAK/STAT signaling pathways; on the other hand, it suppresses angiogenesis through vascular endothelial growth factor receptor (VEGFR) and platelet-derived growth factor receptor (PDGFR) as well.