Using spatial RNA profiling and IHC analysis of an extended cohort of human benign and tumor melanocytic lesions, including epidermal tissue, Kiuru et al. strongly identified keratinocytes in the proximity of melanoma cells as a site of enhanced expression of S100A8 and S100A9 proteins [220], confirming previous sporadic observations [221,222,223]. The gene discussed is S100A9; the disease is neoplasm.