HHLA2 and colorectal carcinoma: As illustrated in Figures 8D, E, most of the 27 immune checkpoints were significantly different between the high and low groups, including CD276, CD70, ICOS, CTLA4, PDCD1 (PD-1), CD274 (PD-L1), PDCD1LG2, BTLA, CD27, CD40, CD40LG, HHLA2, TNFRSF18, TNFRSF4, ICOSLG, TNFRSF9, TNFSF14, LAG3, HAVCR2, ENTPD1, and NCR3 (all P < 0.05), which provided potential ICB therapeutic targets for CRC patients.