MCAM and melanoma: While we cannot completely exclude the possibility that JM1-24-3 could have additional, functionally relevant melanoma targets, we submit that the data provided are strong evidence that JM1-24-3 recognizes a specific conformational epitope on MUC18, and in binding to that epitope induces downstream signaling events that mediate the metastatic phenotype, thus identifying the MUC18 conformational epitope as a promising therapeutic target potentially amenable to mAb treatment.