CTLA4 and colorectal carcinoma: CMS2 and the IFN-γ–dominant subtype share a similar immune status, including strong immune activation (higher proportions of activated CD8+ T cells, activated CD4+ T cells, Tregs, dendritic cells, and M1/M2 polarization) as well as the upregulation of immune checkpoints (CTLA-4 and PD-1/PD-L1), which means that these subgroups of CRC patients may benefit more from ICIs treatment.