CD8A and cancer: A pan-cancer study43 with 16 scRNA-seq datasets (including 11 different tumor types) highlighted an association between high CDA levels in cancer cells and a ‘cold’ immune microenvironment (that is, negative correlation with average expression of PRF1 or IFNG in CD8+ T cells versus a positive correlation with average expression of protumoral P2RY6, CD204, CD163 or MRC1 in TAMs with respect to average expression of CDA in cancer cells across these 16 datasets; Fig. 8c).