SPP1 and melanoma: We next searched KEGG pathways and GO terms associated with highly expressed genes in subcluster “Spp1 + ”, which revealed that subcluster “Spp1 + ” was distinguished by upregulation of genes involved in the melanocyte differentiation and melanoma (Fig. 6H and Supplementary Fig. S7D), including an oncogenic transcription factor Mitf (Supplementary Fig. S7D).