In this study, we report that disruption of PD-L1/PD-1 binding by αPD-1 and αPD-L1 antibodies, rapidly (within 6 h) increased KCa3.1 and Kv1.3 activities in CD8+ PBTs of HNSCC patients. Here, KCNN4 is linked to head and neck squamous cell carcinoma.