CTLA4 and cancer: It was discovered that DCLRE1B expression was positively associated with ICP genes in many types of cancer, especially in PAAD, in which the correlation coefficients of DCLRE1B with PD-1, PD-L1, PD-L2, and CTLA4 were 0.358, 0.577, 0.593 and 0.378, respectively (Figs. 6C-D).