Clinical roles of increased populations of Foxp3+CD4+ T cells in peripheral blood from advanced pancreatic cancer patients

Objectives: Further metastasis should be avoided in pancreatic cancer (PC) patients for effective surgical treatment. Regulatory T cells (Foxp3(+) CD4(+) T cells including CD4(+)CD25(+) T cells and CD4(+)CD25(-) T cells) play important roles in tumor immunity. This study aimed to investigate whether regulatory T cells participate in metastasis. Methods: Peripheral blood was withdrawn from PC patients, as well as healthy volunteer donors as controls. The peripheral blood mononuclear cells (PBMCs) were subjected to FACScan analysis after labeling with anti-CD4, anti-CD25, and anti-Foxp3 antibodies. Tumor markers, including DUPAN2 and CA19-9, surface markers, such as the CD4/ CD8 ratio, and the CD57(+) cell population were assessed. Clinical stages were classified according to the TNM classification. Results: The Foxp3(+)CD4(+) T-cell population among the PBMCs was significantly increased in PC patients (8.10%+/- 4.65%) compared with healthy donors (2.47 +/- 0.78%) (P < 0.001). No significant relationships existed for the tumor markers, CD4/CD8 ratio, and CD57(+) cells. However, a significant correlation was found between Foxp3(+)CD4(+) T cells among the PBMCs and the TNM stage (P < 0.05). Conclusions: Foxp3(+)CD4(+) T cells are good markers for metastasis detection in PC patients and more accurate than other conventional tumor markers, especially at advanced stages of the disease.