RAF1 and neoplasm: Sorafenib is an oral drug originally designed to inhibit RAF serine/threonine kinases (RAF-1, wild-type BRAF, V600E BRAF), but later in vitro studies indicated its efficacy against several receptor tyrosine kinases associated with tumor angiogenesis, such as VEGFR-2, VEGFR-3, PDGFR-β, and progression such as c-KIT and FLT-3 [87].