In particular, exosomes of melanoma patients were shown to display higher protein levels of melanoma inhibitory activity (MIA), a small soluble protein of 11 kDa secreted by malignant melanoma cells, and S100B, a 21-kDa dimeric calcium-binding protein biomarker for malignant melanoma, known to contribute to melanoma progression at metastatic niche (46, 178). This evidence concerns the gene S100B and melanoma.