MAP2K7 and melanoma: Chronic exposure of cultured melanoma cells to BRAF and/or MEK inhibitors leads to an initial response phase characterized by the induction of MITF and enrichment of MITFhigh populations, followed by emergence of CD36+ SMC populations, which subsequently undergo continuous dedifferentiation, and a final state of acquired resistance marked by a predominance of slow-cycling NCSC-like NGFRhigh cells (Figure 4) (54, 77, 78, 80, 185).