Moreover, we analyzed the correlation among four-gene signature (FeSig) (BID, TAZ, MT1G, and SLC7A11), downstream hub genes (CPNE7, WNT10B, ADAMTS14, and RUFY4), and immune checkpoints (PD-1, CTLA4, LAG3, and TIGIT) to further discover potential molecular mechanisms of tumor immunity. The gene discussed is CTLA4; the disease is neoplasm.