Effects of Gastric Cancer Cells on the Differentiation of Treg Cells

The aim of this study was evaluated the prevalence of Treg cells in peripheral blood in patients with gastric cancer, and investigate the effect of gastric cancer cells on their differentiation. ELISA was employed to assess the concentrations of TGF-beta and IL-10 in gastric cancer patients' serum. Then, mouse gastric cancer cells were co-cultured with T lymphocytes or T lymphocytes + anti-TGF-beta. Flow cytometric analysis and RT-PCR were then performed to detect Treg cells and TGF-beta and IL-10 expression in gastric cancer cells. Our data showed that the expression of TGF-beta and IL-10 in the patients with gastric cancer was increased compared to the case with healthy donors. The population of Treg cells and the expression levels of TGF-beta and IL-10 in the co-culture group were much higher than in the control group (18.6% vs 9.5%) (P<0.05). Moreover, the population of Treg cells and the expression levels of TGF-beta and IL-10 in the co-culture systerm were clearly decreased after addition of anti-TGF-beta (7.7% vs 19.6%) (P<0.01). In conclusion, gastric cancer cells may induce Treg cell differentiation through TGF-beta, and further promote immunosuppression.