IDO1 and colonic neoplasm: The results indicated significantly increased expression levels among these checkpoint genes in the high-immunity group, including BTLA, CTLA4, IDO1, LAG3, and PDCD1 (Figure 6), which suggested that colon cancer patients in the high-immunity group could exhibit a better response to immune checkpoint inhibitors, such as CTLA4 and PD1 inhibiting reagents.