CD8A and neoplasm: Interestingly, in N region, the presence of PD-1 in CD8+CD161+ T cells resulted in higher levels of TNF-α, IL-2, and PRF in comparison with CD8+CD161+PD-1− T cells, while CD8+CD161+PD-1− T cells showed opposite trend of TNF-α and IL-2 levels in tumor tissues (Fig. 3e), indicating that CD8+PD-1+CD161+ T cells adjacent to tumor tissue have stronger immunity activity (Fig. 3f).