GZMB and colorectal carcinoma: Our data provide important insights into the distribution of T cells within the TME; subsets of CD4+ T cells and DP T cells have been shown to have immunosuppressive roles in CRC [31,32,33], while DN T cells may also exhibit immunoregulatory potential [34] but CD8+ T cells within TME show potent anti-tumor activity evident from granzyme B expression [35].