Susceptibility of BRAF/NRAS wild-type melanoma to SCH-722984. A. IC50 (nM). Cells were treated with 0–10 μM SCH-722984 (black bars) or vemurafenib (grey bars) and cell viability determined by ATP-based bioluminescence assay. Results are the mean of duplicate experiments, performed in triplicate (n = 6). Error bars are standard deviation. Bar at 1 μM denotes threshold between sensitive and intermediate. Resistant cell lines have IC50 higher than 2 μM. B. Effects of SCH722984 on MAPK signaling. SCH-722984-resistant M257 and SCH-722984-sensitive M285, were treated for 24 h with DMSO (-) or 500 nM SCH722984 (+). Phosphorylated or total MEK, ERK 1/2, RSK, AKT or beta-actin as loading control were determined by western blot analysis.