ABCB5 and melanoma: Because the initiation and progression of vertical growth in human melanoma are fundamental for the notion of tumor virulence and progression, we decided to collect and analyze CMCs from melanoma patients AJCC stage > pT1b (i.e., transition from radial to vertical phase), improving highly aggressive cell recovery of three subpopulations based on MCAM/MUC18/CD146, ABCB5, or biphenotypic MCAM/MUC18/CD146-ABCB5 expressions.