CD274 and head and neck squamous cell carcinoma: Pembrolizumab, a PD-1/PD-L1 inhibitor, has been approved as treatment for HNSCC due to its ability to significantly improve overall survival (OS) in patients.[5–7] However, many patients still do not respond to pembrolizumab,[8] and the 5-year survival rate for HNSCC remains below 50%.[9] Given these challenges, it is imperative to delve deeper into the intricacies of the TME and identify new therapeutic targets for immunotherapy.