To evaluate the impact of MC1R on T-cell infiltration and activity in human melanoma, we examined the expression levels of multiple lineage (CD45, CD3D/E/G, and CD8A/B) and phenotypic markers (PRF1, GZMA, GZMH, GZMK, KLRK1, NKG7, IFNG, CD69, CD96, and LAG3) of CD8+ cells in MC1R-high versus MC1R-low non-RHC melanomas. This evidence concerns the gene GZMK and melanoma.