In particular, both situations were characterized by reduced gene expression of Cd7, a marker of mature CD8+ T cells, of Cd8a itself, of the granzymes Gzma and Gzmb and of Prf1 for cytotoxic T lymphocytes, together with the repression of the IFN gamma pathway, a major regulator of colon tumor immunity [21]. Here, PRF1 is linked to colonic neoplasm.