CD4~+CD25~+/CD4~+CD25~(high) regulatory cells in peripheral blood of cancer patients

Objective: To investigate the frequencies of CD4+ regulatory T(Treg) cells(CD4+CD25+/CD4+CD25high) in peripheral blood of cancer patients,providing the opportunity to determine whether cancer patients exhibit an expanded CD4+CD25high pool. Methods: The frequency of CD4+CD25+/CD4+CD25high Treg in the peripheral blood of 62 cancer patients and 15 controls was determined by flow cytometry. Results: Compared with those of healthy control, the frequency of CD4+CD25+/CD4+CD25high in the peripheral blood of cancer patients showed a significant increase[(19.61±8.17)%/(4.20±1.90)%,P0.05,P0.001, respectively]. There was negative relation between the level of CD4+CD25+/CD4+CD25high and that of NK(r=-0.236 1,-0.306, respectively). Compared with those in patients of stage(Ⅰ+Ⅱ) and stage Ⅲ, the frequency of CD4+CD25+ in patients of stage Ⅳ showed significant increase(P0.001). Compared with the level in healthy controls and patients of stage(Ⅰ+Ⅱ), the frequency of CD4+CD25highT cells in patients of advanced stage[Ⅲ:(3.52±1.51)%,n=21;Ⅳ:(4.85±1.67)%,n=26] was significantly higher(P0.001,both), and there was significant difference between the frequency of CD4+CD25+/CD4+CD25high in patients of stage Ⅲ and that of stage Ⅳ. Conclusion: The relative increasement in CD4+CD25+/CD4+CD25high regulatory T cells may be related to immunosupression and tumor progression in patients with malignancies.