Then, we further compared the expression levels of common immune checkpoints within the two groups, and the results manifested that PD-1, PD-L1, and CTLA4 were all significantly augmented in the high-risk groups of both GSE40967 (Figure 6C) and TCGA-COAD data sets (Figure 6D), which unearthed the fact that COAD patients of high-risk groups may have an immunosuppressive TME and may also respond better to immunotherapy targeting the immune checkpoints. Here, CTLA4 is linked to colon adenocarcinoma.