Moreover, the inverse relationship between PD-L1 expression in CRC cells and PD-L1+ TILs observed in the current study (p < 0.001) agreed with Kim et al [40] who showed the inhibitory effect that PD-L1 expression in CRC cells exerted on TILs through inhibiting their proliferation and inducing apoptosis, thus reducing their density. This evidence concerns the gene CD274 and colorectal carcinoma.