As indicated in Figure 8A, we found that tumor purity was only negatively related to three immune genes, namely, CD8A (R = −0.18, p = 1.06 e-06), CXCR2 (R = −0.18, p = 2.90 e-07), and TNFRSF14 (R = −0.21, p = 2.58 e-09), but not to other immune-related genes, including the well-known PD1, PD-L1, and CTLA4. This evidence concerns the gene CTLA4 and neoplasm.