RAF1 and renal cell carcinoma: Due to the broad specificity of sorafenib this drug has been evaluated for the therapy of diverse cancers, including RCC, melanoma and HCC (due to the involvement of the Raf/MEK/ERK cascade, as well as altered VEGFR pathway in these cancers) and gastro-intestinal stromal tumors (GIST) (due to the involvement of KIT mutations in this cancer).