The Influences Of Stage And Chemotherapy On The Changes Of The Proportion Of The CD4~+ CD25~+ Foxp3~+ Regulatory T Cells In The Peripheral Blood Of Breast Cancer Patients And Its Clinical Significance

ObjectiveCD4+CD25+FoxP3+regulatory T cells (Tregs) are important mediators of peripheral immune tolerance, acting via multiple mechanisms to suppress cellular immunity including antitumor responses. The immune treatment to cancer has been focused on the Tregs. Here ,we investigated the changes of the porportion of Tregs in different stages and the effect of chemotherapy on Tregs in the peripheral blood of breast cancer patients.Materials and method1. Group: This study included twenty female healthy volunteers as control (control group),twenty female patients with breast benign tumors (benign group) and fifty four patients of breast cancer (breast cancer group) , treated in our department from 2009 to 2010. In the breast cancer group, seven patients in stage 0 (DCIS),nine patients in stage I, twenty-two patients in stage II, ten patients in stage III, and six patients in stage IV.2. Treatment: the patients of benign group were operated by MMT(mamotome);patients of stage 0,I,IIA were operated and then patients of stage I,IIA were given chemotherapy with FEC*6 or FEC*3-T*3; patients of stage IIB,III were given neoadjuvant chemotherapy with TEC*3 and evaluated the efficiency; patients of stage IV were given palliative chemotherapy with TEC/NP/NX.3.Sample colletion: all patients in this study were extracted 4ml peripheral blood before surgery; patients of stage I,IIA were extracted 4ml peripheral blood at the seventh day after operation and the tenth day after the last chemotherapy; patients of stage IIB,III were extracted 4ml peripheral blood at the tenth day after the third chemotherapy and the last chemotherapy.4.Sample dealing: peripheral blood mononuclear cell were isolated by density gradient centrifugation.5.Flow cytometry measuring: Tregs were immunolabelled by CY5 anti-human CD4,PE anti-human CD25,FITC anti-human Foxp3,then were measured by flow cytometry, positive cells were showed in percentage.6.The data was analyzed by spss13.0 with independent-sample t test and paired-sample t test.ResultsThe first part, the changes of proportion of Tregs in the peripheral blood of breast cancer patients in different stages and its significance.1.1 The proportion of Tregs in the peripheral blood in cancer group(1.34±0.51)%was significantly higher than that in benign group(0.81±0.21)% and control group(0.75±0.19)%(p<0.05),but there was no different between benign group and control group(p>0.05).1.2 Tregs in the peripheral blood in breast cancer group was increased significantly as the stage of the disease increased, and that was obviously higher in the patients of stage III,IV than that in the patients of stage I,II(p<0.05).1.3 A significant positive correlation was found among the proportion of Tregs in the peripheral blood and tumor size,histological grade, lymph nodes and Her-2 status(p<0.05). The proportion of Tregs in the peripheral blood in breast cancer patients were all significantly increased with tumor more than 2cm, high histological grade (III) , lymph nodes infiltration and Her-2 positive(p<0.05).The second part ,the influence of chemotherapy on the proportion of Tregs in the peripheral blood of breast cancer and its siginificance.2.1 After chemotherapy, the proportion of Tregs (0.92±0.32)% was significantly lower in patients of stage I ,IIA ,when compared with that before chemotherapy (p<0.05).2.2 After neoadjuvant chemothery, the proportion of Tregs in the patiens who got CR and PR were both significantly decreased than that before neoadjuvant chemothery(P<0.05),but there was no statistical significance achieved between preochemothery and post chemotherapy in the patients who got SD(p>0.05).Conclusions1. Before treatment, the proportion of Tregs in the peripheral blood was signifcantly higher in breast cancer patients, compared with that of control and benign group. Furthermore, the proportion of Tregs was significantly increased as the stage of the breast cancer increased. It was indicated that Tregs may be responsible for the immune inhibition to antitumor responses, and involved in tumor onset and progression in human primary breast cancer .2. A significant positive correlation was found among the proportion of Tregs in the peripheral blood and clinical stage, tumor size, histological grade lymph nodes and Her-2 status. It was suggested the Tregs in the perpheral blood may be valuable for assessing breast cancer prognosis.3. The proportion of Tregs in the peripheral blood was reduced by chemotherapy, which caused relieving immunity suppression of breast cancer patients. Maybe the Tregs would become one of the new therapy targets of breast cancer.4. After neoadjuvant chemothery, the proportion of Tregs in the peripheral blood of the patients with PR, CR significantly decreased. It was concluded that Tregs could be a factor to assess the efficiency of therapy of neoadjuvant chemothery.