Indeed, adoptive transfer of Tregs in mice has been shown to suppress colitis-associated colon cancer and intestinal adenomas [69], [70] and this could likely be due to the ability of Tregs in reducing the effects of chronic inflammation by down-regulating the expression of cyclooxygenase-2 and pro-inflammatory cytokines including TNF-α and IFN-γ. This evidence concerns the gene PTGS2 and colitis.