Regarding tumor-infiltrating B cells, Bregs from head and neck squamous cell carcinoma (HNSCC) patients produced adenosine to dampen the phosphorylation of Bruton’s tyrosine kinase (BTK) and Ca2+ influx in effector B cells; thus adenosine signaling may be a possible therapeutic target in HNSCC (47). The gene discussed is BTK; the disease is head and neck squamous cell carcinoma.