BRAF and melanoma: ,8 Earlier studies identified melanoma cells from two main distinct transcriptional cell states based on the expression of the MITF transcription factor, which drives the gene expression program of differentiated melanocytic-type cells, or the receptor tyrosine kinase AXL, a marker of undifferentiated mesenchymal-type cells.9, 10, 11 Targeted therapy with BRAF/MEK inhibitors has effect against BRAF-mutated melanoma.12