MRC1 and colorectal carcinoma: Of note, the TME of MMR-deficient, microsatellite-unstable, ICB-sensitive human CRC—unlike MMR-proficient, microsatellite-stable, ICB-insensitive human CRC—contains foci of tumor cells interacting with TILs and stromal cells, all of which have inflammatory gene signatures (Pelka et al, 2021).