KLF4 and cancer: Interestingly, we also observed an up-regulation in NANOG (Nanog homeobox), ABCC2 and 5 (ATP binding cassette subfamily C member 2 and 5), CD44 (CD44 molecule (Indian blood group) and KLF4 (Kruppel like factor 4), all cancer stem cells related genes, which suggests that the acquisition of a stemness phenotype by melanoma cells promotes cell survival under chemotherapy.