Developing next-generation ICIs targeting different pathways beyond PD-1, PD-L1, and CTLA-4 is also inevitable [42]; utilizing biomarkers to predict the occurrence of resistance by detecting patients' biomarkers and adjusting treatment strategies in advance [43]; and applying extra therapies such as cell therapies, cancer vaccines, and OVs to provide new treatment options for resistant patients [44]. The gene discussed is CTLA4; the disease is cancer.