CD8A and neoplasm: Moreover, we observed statistically significant correlations between PD-1 and TIGIT expression in CD4+ T cells in AEM (r = 0.4769, p = 0.0159; Figure 5B) and tumor tissues (r = 0.5121, p = 0.0089; Figure 5C), and in CD8+ T cells in PBMC (r = 0.3888, p = 0.0210; Figure 5A) and tumor tissues (r = 0.4793, p = 0.0153; Figure 5C).