ATG7 and head and neck squamous cell carcinoma: However, further analysis of the correction between ATG7 and immunosuppressive checkpoints showed that high expression of ATG7 was correlated with high expression of PD-L1 (r = 0.340, P < 0.001), PD-1 (r = 0.410, P < 0.001), and CTLA4 (r = 0.400, P < 0.001) in HNSCC, which implied that ATG might be involved in immunosuppression in HNSCC (Figures 4(d)–4(e)).