Regulatory T-lymphocyte cells in patients with gastrointestinal malignancies

The subpopulations of regulatory T cells (Treg) were investigated in peripheral blood and lymph nodes of patients with different stages of gastric (GC, n=13) and colorectal carcinomas (CRC, n=10). It was revealed that in patients with GC the СD4+СD25+ and СD4+СD25high cells were increased only in peripheral blood. On the contrary, patients with CRC were characterized by increased level of CD4+CD25+/CD4+CD25high Treg in the lymph nodes and decreased level in bloodstream. These changes were strongly pronounced in III-IV stages of disease. The population of CD4+FOXP3+ Treg was increased in peripheral blood and, particularly, in the lymph nodes of patients with gastrointestinal malignancies (GC and CRC). The number of CD4+FOXP3+ cells was inversely correlated with functional (proliferative) activity of T cells. Thus, we conclude that patients with gastric and colorectal carcinomas are characterized by contradictory changes of Treg subsets on systemic and locoregional levels, nevertheless, the decrease in T-cell proliferative activity is associated with expansion of CD4+FOXP3+ T-cells.