PROCA1 and head and neck squamous cell carcinoma: Of these, 6 hub FAMRGs (ACSL5, PLA2G2D, PROCA1, IL4I1, UBE2L6 and PSME1) were found to affect PD‐1 expression and T cell infiltration in HNSCC, which may impact the efficacy of anti‐PD1 therapy.