Using p16 immunostaining and HPV DNA in situ hybridization technique to monitor HPV infection, we found that there was no statistically significant difference in PD-1/PD-L1 expression in HPV+ (n = 12) and HPV- (n = 74) HNSCC (Fig. 1C and 1D). The gene discussed is CD274; the disease is head and neck squamous cell carcinoma.