BRAF and melanoma: Consistent with BRAF kinase inhibition in vitro, AZ304 potently reduced ERK phosphorylation (p-ERK), with a mean EC50 of 65 nM in the V600E mutant BRAF containing melanoma cell line A375 (Fig. 1b); an EC50 of 60 nM was obtained for the wild type BRAF melanoma cell line SK-MEL-31(Fig. 1c).