RESUMO
AIM OF THE STUDY: To investigate the percentage of CD4+CD25(high) cells (including Treg cells) and CD8+CD28- cells in breast cancer patients with and without high levels of autoimmune thyroid antibodies. MATERIAL AND METHODS: Thirty-five women with breast cancer (9 of them having high thyroid antibodies) and fourteen healthy subjects were enrolled in this study. Flow cytometry was used to count CD4+CD25(high) cells and CD8+CD28- suppressive cells (CD8 cell subtypes). RESULTS: In the patient group, the percentage of CD28- cells in CD8+ lymphocytes were higher [67.50% (55.1180.33) vs. 51.56% (42.5766.38); p = 0.021] and the percentage of CD28+CD45RO- cells (memory cells) in CD8+ lymphocytes were lower than in the control group. CD4+CD25(high) cell percentage in CD4+ lymphocytes was elevated in the patient group [6.44% (4.528.74) vs. 2.97% (1.724.34); p < 0.001]. When the cytometric parameters were compared between patients (with high vs. normal thyroid antibodies), the distribution of CD8+ cell subgroups was also similar. CD4+CD25(high) cells among CD4+ lymphocytes were decreased in patients with high levels of thyroid antibodies [5.19% (3.426.17) vs. 6.99% (4.829.95); p = 0.043]. CONCLUSIONS: CD4+CD25(high) cells may play a role in autoimmunity of breast cancer patients, and may be a predictive marker. Advanced studies which evaluate the possible links between regulatory cells and autoimmunity should be established in cancer patients.
