雄激素刺激共转录导致R-LOOPs形成诱导DNA损伤促进AR+三阴乳腺癌发生发展的实验研究

R-LOOP是新发现的遗传调控机制，对维持基因组稳定性发挥重要作用。我们前期研究发现AR+TNBC存在高水平R-LOOP，其预后差于AR+R-LOOP-，推测AR+TNBC中雄激素可能通过诱导R-LOOP形成导致基因组不稳定，影响肿瘤发生发展。我们将通过检测R-LOOP在AR+TNBC原发肿瘤中的水平了解其与临床病理预后关系。通过免疫组化、DRIP-SEQ、RNA测序、CHIP-SEQ、co-IP等方法检测AR+TNBC细胞株雄激素刺激后R-LOOP、DNA损伤变化，研究AR活化是否会诱导R-LOOP依赖的基因组不稳定，R-LOOP的发生部位和DNA损伤位点的关系，上调RNaseH表达等降低R-LOOP治疗是否可以抑制肿瘤的增殖，其与化疗、抗雄治疗、PARP-1抑制剂、CDK4/6抑制剂联合是否具有协同作用。本研究将为探讨AR+TNBC发病机制、开发针对R-LOOP机制靶向治疗奠定基础。

R-loop is a new genetic regulation mechanism that plays an important role in maintaining genome stability. Our previous study found that AR + TNBC has a high level of R-loop, the prognosis of patients with AR+R-LOOP+ is worse than AR + R-loop-, thus androgen may induce R-loop-dependent genomic instability with similar mechanism in AR+TNBC to promote tumor development. In this study,we will detect the level of R-loop in primary breast cancer to explore the relationship between R-LOOP level and clinical pathological factors.we will treat AR+TNBC cell line and sequecing these cells with RNA sequencing, DRIP-SEQ and CHIP-SEQ to detect the changes of R-loop level and DNA damage in the whole genome to investigate whether AR activation could induced R-loop and genomic instability,the relationship between the site of the R-loop and the locus of DNA damage, and whether the down regulation of R-loop by overexpression of RNase H could inhibit the proliferation of the AR+TNBC cell lines, whether there is a synergistic effect in the treatment of AR+TNBC among conventional chemotherapy, anti-androgen therapy, PARP-1 inhibitor, CDK4/6 inhibitor. This study will lay the foundation for the development of R-loop targeted therapy for AR+TNBC.