CD274 and colorectal carcinoma: In CRC, Fusobacterium nucleatum enhances PD-L1 blockade efficacy by activating STING/NF-κB pathways, upregulating PD-L1, and recruiting IFN-γ+ CD8+ TILs—validated in PDO co-cultures via suppressed proliferation and induced apoptosis (Figure 1C) [46].