The results reveal that the expression levels of KRAS are significantly correlated with the infiltration levels of B cells, CD8+T cells, CD4+T cells, macrophages, neutrophils, and dendritic cells in 10, 13, 8, 9, 11, and 7 cancer types, respectively (correlation threshold ∣ R > 0.2, p < 0.05) (Figure 9 and Supplementary Figure S5). This evidence concerns the gene CD4 and cancer.