Going back to cancer development, whereas the 3E model consists of elimination, equilibrium and escape, immunotherapy could be described by the 3R model: reverse by, e.g., CTLA-4, rejuvenate by, e.g., CAR-T cells and restore by anti-PD-1/PD-L1 and further tumor-associated immune checkpoint inhibitors [116]. The gene discussed is CTLA4; the disease is neoplasm.