乳腺癌的发生与CD4+CD25+调节性T细胞（Tregs）介导的免疫逃逸密切相关。新近研究显示miRNAs在Tregs功能和发育中起关键调控作用。在前期研究中，我们发现Tregs的CCR6+群体在临床乳腺癌肿瘤局部明显富集，且其富集与肿瘤局部CD8+T细胞功能低下和患者预后密切相关，然而该群体的功能调控机制仍不明。在此基础上，本项目拟从最新的miRNAs调控角度出发，用Solexa测序结合Real-time PCR检测乳腺癌小鼠模型及临床患者CCR6+Tregs的特征miRNAs表达；进而利用慢病毒载体表达系统改变特征miRNAs的表达，观察其对CCR6+Tregs功能相关分子、抑制功能和增殖活性能力的影响；进一步利用基因芯片技术结合WB来探讨特征miRNAs作用的靶分子机制。项目预期结果可为后续深入探讨乳腺癌发生中Tregs群体的功能调控机制及临床免疫生物治疗靶标开发提供新的实验依据。

Accumulating data showed that CD4+CD25+ regulatory T cells （Tregs）played an important role in the development of breast cancer through mediating immune escape. Most recent evidences showed that miRNAs played an critical role in the regulation of function and development of Tregs. Our previous data showed that CCR6+ subset of Tregs accumulated in tumor mass, which was closely related to the dysfunction of CD8+T cells in tumor mass and the poor prognosis of breast cancer patients. However, the underlying mechanism through which regulates the function of CCR6+Tregs remains largely unknown. In the present study, we aimed to detect and establish the typical profile of miRNAs on CCR6+ regulatory T cells from murine breast cancer model and breast cancer patients using Solexa sequencing technology. And we further investigated the possible effect of specific miRNAs on the suppressive function and activity ability, as well as the expression of functional molecules, of CCR6+ regulatory T cells through altering specific miRNAs expression using lentivirus expression vector. Moreover, the potential target molecules of specific miRNAs also were identified by using gene chip technology combined western blot. This prospective data would provided evidence for successive study on the mechanism through which regulates the function of Tregs in immune escape of breast cancer and for the exploration of related immunobiological therapy of breast cancer.