Consistently with transcriptomic data, immunohistochemical analysis of human melanoma tissue microarrays showed higher proportion of metastatic cases with medium/high ST3GAL1 staining compared to primary melanomas (p = 0.0198) or nevi (p = 0.0007; Fig. 2d, e and Supplementary Table 1). This evidence concerns the gene ST3GAL1 and melanoma.