Melanoma stem cells, in particular, are characterized by the expression of embryonic transcription factors (Vandamme et al., 2014; Seftor et al., 2019), including NANOG (Homeobox protein), Oct4 (octamer-binding transcription factor 4) and Sox2 (sex-determining region Y HMG-box 2). This evidence concerns the gene SOX2 and melanoma.