CD274 and head and neck squamous cell carcinoma: The combination of nanosatellite vaccine with anti-PD-L1 not only promotes CD8+ CTL but also reduces CTL exhaustion, delivering superior protection (148).In HNSCC, specific antigens such as HR-HPV oncogenic proteins, p53 and CSC-related proteins can prime immune cells to induce a robust immune responses (169, 171).