It has recently been shown that the phospho-ERK staining was not correlated with the mutational status of NRAS and/or BRAF in melanoma tissues, and that cultured BRAF-mutant melanoma cells downregulated RAS/RAF/MEK/ERK activation when cultured at high densities or under non-adherent conditions (Houben et al, 2008). Here, BRAF is linked to melanoma.