The functional and prognostic implications of regulatory T cells in colorectal carcinoma

One of the cornerstones for the immune system is the discovery of T-regulatory cells (Treg), which play an essential role in maintaining self regulation of the immune response to foreign threats. However, they may also interfere with the immune response to tumoral cells, for which reason much effort has been put into characterizing the molecular makeup of this T cell population. It has been shown that Tregs are increased in the peripheral blood of patients with many cancer types, and also enriched in the tumor sites. However, the significance of this phenomenon on prognosis is controversial, especially in colorectal carcinoma, one of the most common cancers worldwide and a major cause of cancer-related death. This literature review focuses on characterization of the Treg cells in colorectal cancer patients and its implications on the prognosis of this disease. In the end, the potential therapeutic strategies aimed at Treg modification are discussed.