In COAD, P4HA3 expression was positively correlated with the expression of PMS2, BTLA, CD200, NRP1, LAIR1, TNFSF4, ICOS, CTLA-4, CD48, CD28, CD200R1, HAVCR2, ADORA2A, CD276, CD80, TNFSF14, PD-1, TNFSF18, TNFRSF8, CD27, VSIR, TNFRSF4, CD40, TIGIT, PD-L1, CD86 and TNFRSF9, and negatively correlated with the EPCAM. The gene discussed is CD200R1; the disease is colon adenocarcinoma.