MCC tumor cells are believed to create a local immunosuppressive milieu by overproducing immunosuppressive elements like TGF‐β, Fas‐L, IL‐10, or T‐cell response inhibitors such as galactoglucan lectin‐1 and indoleamine 2,3‐dioxygenase (IDO). The gene discussed is TGFB1; the disease is neoplasm.