PDCD1 and colon adenocarcinoma: Through the correlation analysis between ISYNA1 expression and immunosuppressive genes, we found that ISYNA1 expression was positively correlated with most immunosuppressive genes and immune checkpoints in COAD, such as TGFBR1, IL10, IL10RB, CTLA4, CD274, PDCD1, TIGIT, and LAG3.