HAVCR2 and neoplasm: In addition to genetic and epigenetic manipulation, the tumor microenvironment (TME), which is made up of immune checkpoints like programmed LAG-3, death-1 (PD-1)/programmed death-ligand 1 (PD-L1), CTLA4, and TIM3 that infiltrate immunosuppressive myeloid cells and regulatory T cells, has a significant impact on the progression and incidence of CRC [22]; this suppresses endogenous anti-tumor immunity and the effects of CAR-T therapy [23].