MAP2K1 and melanoma: In order to examine the specific perturbations in Ras/RAF/MEK/ERK signaling underlying the sensitivity of MEK1 Q56P melanoma cells to combination MEK/BRAF inhibitor treatment, MEK1 Q56P cells were treated with either dabrafenib, vemurafenib, trametinib, binimetinib, doxorubicin, or a combination drug treatment consisting of a half-dose of dabrafenib plus a half-dose of trametinib.