ABCG2 and melanoma: Interestingly, ABCG2+ melanoma stem cells showed the highest expression levels of epithelial to mesenchymal transition (EMT) genes, including Twist basic helix-loop-helix transcription factor 1 (TWIST), Snail family of zinc-finger transcription factors (SNAIL), Snail Family Zinc Finger 2 (SLUG), CDH-2/N-cadherin, VIM, SPARC [54] highlighting EMT and cancer stemness are intertwined aspects in melanoma biology and progression.