Among the 159 genes identified in the ICON7 training set, we found that the 103 genes associated with total CD8+ T-cell quantities mostly constituted a cytotoxic signature (e.g., GZMA, GZMB, GMZH, CD40LG) and served as the primary feature to distinguish the desert tumours from the infiltrated and excluded tumours (Fig. 3a). This evidence concerns the gene GZMB and neoplasm.