Sorafenib did not affect the expression of ERK1/2 but dramatically reduced the phosphorylation level of both pERK1/2, confirming the role of sorafenib in inhibition of ERK1/2/MAPK pathway by targeting RAF.10 Incubation of tumour cells with either M2-CM or exogenous HGF partially abolished the suppression of pERK1/2 phosphorylation by sorafenib. The gene discussed is RAF1; the disease is neoplasm.