Among this class of molecules with a role in melanoma, and radial growth phase (RGP) (horizontal expansion) to vertical growth phase (VGP) evolution, MCAM/MUC18/CD146, also cited as A32 antigen, MelCAM, or S-Endo-1, has been recently identified [1,2,3], and we will refer to this protein as CD146 throughout this entire manuscript. The gene discussed is MCAM; the disease is melanoma.