In addition, a number of clinical trials have made breakthroughs in immunotherapy using immune checkpoint inhibitors against HNSCC, and a number of combined anti-CTLA-4 and anti-PD-1/L1 clinical trials are also underway (Ferris et al., 2020; Maio et al., 2021; Masarwy et al., 2021). This evidence concerns the gene CTLA4 and head and neck squamous cell carcinoma.