To further support the relevance of this regulation during melanoma progression, single-cell analysis in cells derived from normal melanocytes and from a melanoma brain metastasis PDX model (M15) showed co-expression of SOX2, BRD4 and GLI1 in a subgroup of metastatic melanoma cells but not in melanocytes (Fig. 3H). This evidence concerns the gene SOX2 and metastatic melanoma.