In HNSCC CD8+ PBTs, anti-PD-1 treatment did not affect the expression of KCa3.1, Kv1.3, Ca2+ release activated Ca2+ (CRAC) channels, and markers of cell activation (CD69) and exhaustion (LAG-3 and TIM-3). Here, HAVCR2 is linked to head and neck squamous cell carcinoma.