CTLA4 and lung carcinoma: The immune checkpoint blockade (ICB) therapy including anti-programmed death 1 (PD-1) therapy, anti-programmed death 1 ligand (PD-L1), and anti-cytotoxic-T-lymphocyte-associated protein 4 (CTLA-4) therapy has been proven to be beneficial in some lung cancer patients in clinical trials (8–12).