三阴性乳腺癌(TNBC)术后易复发转移，生存预后差。化疗药物敏感性降低是TNBC生存预后不佳的重要原因。circRNA是一种新型非编码RNA, 与肿瘤发生发展密切相关。前期预实验发现，circFNDC3B在TNBC组织及细胞系中低表达，与生存预后相关。过表达circFNDC3B可抑制TNBC细胞增殖、侵袭和增加顺铂化疗敏感性。circFNDC3B可靶向调控miR-93-3p/SFRP1，而SFRP1可激活Wnt/β-catenin信号通路。因此，申请者提出：circFNDC3B通过吸附miR-93-3p从而升高SFRP1表达，激活Wnt/β-catenin信号通路，进而增加TNBC顺铂化疗敏感性。本项目拟结合细胞及动物实验，阐明circFNDC3B/miR-93-3p/SFRP1轴调控三阴性乳腺癌生长转移和顺铂化疗敏感性的分子机制，为提高TNBC顺铂化疗疗效提供新的理论依据和治疗靶点。

Patients with triple negative breast cancer (TNBC) are prone to poor prognosis, because of recurrence and metastasis. The important cause of poor survival prognosis in TNBC patients is decreased chemosensitivity. As a novel type of non-coding RNA, cirRNAs play important roles in tumor development and progression. Based on our previous data, we found that circFNDC3B overexpression can severely suppress TNBC cell proliferation, invasion and increase cisplatin chemosensitivity. circFNDC3B can regulate miR-93-3p/SFRP1, and SFRP1 can activate Wnt/β-catenin signaling pathway. Thus, our program proposed that circFNDC3B sponges miR-93-3p to increase SFRP1 expression and activate Wnt/β-catenin signaling pathway to increase cisplatin chemosensitivity. In the following experiments, we will explore the growth, metastasis and cisplatin chemosensitivity mechanism of TNBC regulated by circFNDC3B/miR-93-3p/SFRP1 axis. Therefore, our study can provide a new molecular therapy of targeting to improve the effect of cisplatin chemotherapy in TNBC.