CTLA4 and colorectal carcinoma: Omura et al. have shown that the overexpression of membrane-bound CTLA-4 and membrane-bound PD-L1 in CRC cells can be associated with worse overall survival and disease-free survival (HR = 3.86, 95%, CI: 1.71–8.51, p-value = 0.001, and HR = 2.53, 95%, CI: 1.23–4.95, p-value = 0.01, respectively) [15].