Sorafenib toxicity is not related to MAPK.

<p>a) ACHN and 786-O cells were treated for 48 h at the indicated concentrations of Sorafenib and viability was assessed by MTT assay. Black bars indicate ACHN and white bars indicate 786-O. b) ACHN and c) 786-O cells were exposed to 10 μM Sorafenib for 16 hours. Protein extracts were blotted against with the indicated antibodies. Tubulin was used as a loading control. d) Cells were treated for 48 h with 10 μM U0126, 10 μM PD98059 or 10 μM SB203580. Viability was measured by MTT assay. Black bars indicate ACHN and white bars indicate 786-O. e) ACHN and 786-O cells were treated with Sorafenib (10 μM) in combination with the indicated inhibitors (10 μM each) for 48 h. Viability was measured by MTT assay. Black bars indicate ACHN and white bars indicate 786-O. Densitometric quantification of the signals on the Western blots is shown for each picture (fold active/total) below each group.