The proportion of partial infiltrating cell subtypes was obviously different between the two groups, among which mostly myeloid dendritic cell, T cell CD8+, neutrophil, macrophage M1, cancer-associated fibroblast, monocyte, myeloid dendritic cell, and macrophage M2 had a higher infiltration scale in the low-PTCD1 group, while T cell regulatory (Tregs), T cell follicular helper, and other types had a lower proportion (Figure 8(a), all P < 0.05). Here, CD8A is linked to cancer.