RESUMO
OBJECTIVE: To investigate the expressions of CD4+ CD25(high) regulatory T cells, TGF-beta 1 and COX-2 in the peripheral blood of prostate cancer (PCa) patients, and analyze the role of CD4+ CD25(high) regulatory T cells in the pathogenesis of PCa and their relationship with TGF-beta 1 and COX-2. METHODS: We used flow cytometry to calculate the percentage of CD4+ CD25(high) regulatory T cells in the CD4+ T cells in the peripheral blood mononuclear cells (PBMC) from 30 PCa patients (11 localized and 19 non-localized cases) and 20 healthy volunteer controls, determined the expressions of TGF-beta 1 and COX-2 in the serum by ELISA, and analyzed their correlation with the CD4+ CD25(high) regulatory T cells in the PCa patients as well as the differences between the localized and non- localized cases. RESULTS: CD4+ CD25(high) regulatory T cells accounted for (18.32 +/- 7.49) % in the CD4+ T cells in PBMCs from the PCa patients, significantly higher than (7.77 +/- 1.86) % from the controls (P < 0.05), but with no statistically significant difference between pre- and post-treatment in the PCa patients (P > 0.05). The expressions of TGF-beta 1 and COX-2 in the peripheral blood were (215.97 +/- 55.16) ng/ml and (6.88 +/- 5.14) ng/ml in the PCa patients, in comparison with (149.75 +/- 47.11) ng/ml (P < 0.05) and (6.88 +/- 5.14) ng/ml (P > 0.05) in the controls. Multiple linear regression analysis showed no significant correlation between the expression of CD4+ CD25(high) regulatory T cells in PBMCs and those of TGF-beta 1 and COX-2 in the peripheral blood of the PCa patients. There were no significant differences between the localized and non-localized PCa groups in the expressions of CD4+ CD25(high) regulatory T cells, TGF-beta 1 and COX-2 (P > 0.05). CONCLUSION: CD4+ CD25(high) regulatory T cells in in PBMCs are involved in the pathogenesis of PCa. The proliferation of CD4+ CD25(high) regulatory T cells is not significantly correlated to the expressions of TGF-beta 1 and COX-2 in the peripheral blood, but maybe to the tumor itself and the local tumor microenvironment.