The utilization of immune checkpoint inhibitors (ICIs) in cancer treatment, including monoclonal antibodies targeting the programmed death receptor (PD-1), ligand of programmed death receptor (PD-L1) and cytotoxic T lymphocyte-associated protein 4 (CTLA-4) receptor, is considered a revolution in cancer therapy that changes the poor prognosis of many malignancies and is widely used in the treatment of advanced-stage cancer [32–39]. The gene discussed is CTLA4; the disease is cancer.