miR-506多靶点调控HR和β-catenin信号通路对浆液性卵巢癌药物敏感性的影响

Ovarian cancer (OvCa) remains the most lethal gynecological malignancy and the majority of patients with OvCa die from tumor recurrence and chemo-resistance. In previous studies of this project, we analyzed the genomic and epigenetic data of OvCa in TCGA (The Cancer Genome Atlas) using integrated bioinformatics analysis and found that among the miRNA network related to mesenchymal subtype with poor survival,miR-506 could inhibit the epithelial-mesenchymal transition process through targeting SNAI2.We also found that miR-506 could inhibit OvCa proliferation and induce senescence through targeting CDK4/6-FOXM1 axis.We further demonstrated that miR-506 level was associated with progression-free survival and overall survival in TCGA data, which was verified in INT-Milan dataset and miR-506 level was related to cispaltin response. Microarray and western blot results showed that overexpression of miR-506 could down-regulate the mRNA and protein level of RAD51 and EZH2. In this project we plan to further analyze the effect and mechanisms of miR-506 on OvCa sensitivity to cispaltin and PARP inhibitor,which may include targeting RAD51, EZH2 and FOXM1 signaling, and regulating homolougous recombination(HR) and β-catenin signaling pathway through in vitro, in vivo and retrospective clinical experiments. We will evaluate the effects of enhanced sensitivity of miR-506/nanoliposomes in OvCa xenografts mouse model. The results of this work will contribute to understand the multi-targeting regulatory function and mechanism of this new microRNA and supply new potential direction and theoretical basis for OvCa treatment.

卵巢癌(OvCa)死亡率高、预后差,患者多死于肿瘤复发和耐药。前期工作通过分析TCGA数据库浆液性OvCa与预后不良间质亚型有关的miRNA调节网络,发现miR-506抑制OvCa上皮-间质转化并促进细胞衰老。课题组对TCGA和INT-Milan数据库的深入分析提示,miR-506是OvCa独立预后因子并与顺铂敏感性相关联,但具体机制不清。本申请以过表达miR-506后的microarray数据为基础,拟通过体外、体内实验和临床病例分析,深入系统地研究miR-506通过多靶点抑制RAD51、EZH2和FOXM1信号,进而调控同源重组修复(HR)和β-catenin信号通路,形成多重复杂功能网络影响OvCa顺铂和PARP抑制剂的敏感性,并评估miR-506/纳米脂质体对OvCa裸鼠移植瘤的化疗增敏作用。通过探讨miR-506调节OvCa药物反应性的机制,为小分子靶向治疗OvCa提供理论依据。

miR-506参与了卵巢癌（OvCa）化疗药物敏感性的调节，本项目通过体外、体内实验和临床病例分析，对miR-506调节OvCa药物敏感性的机制进行了初步探究。首先，通过Target Scan 6、荧光素酶报告基因体系预测并验证了miR-506可能的靶基因RAD51、EZH2。一方面，通过western blot分析在miR-506过表达或敲除条件下RAD51蛋白水平的表达情况，结果显示miR-506可抑制RAD51表达。随后，通过HR检测体系、彗星实验，证实miR-506介导的RAD51表达下调可阻碍DNA损伤修复通路；进而利用克隆形成实验发现miR-506可通过抑制RAD51来发挥增强顺铂和PARP抑制剂药物敏感性，并应用补救实验、体内动物实验和临床组织样本验证了上述结论。另一方面，通过western blot分析在miR-506过表达或敲除条件下EZH2、β-catenin蛋白水平的表达情况，结果显示miR-506可靶向抑制EZH2-β-catenin信号转导通路。CCK8、集落形成实验结果证实miR506可以通过抑制EZH2-β-catenin的表达来影响对顺铂和奥拉帕尼的敏感性。补救实验、体内动物实验和临床组织样本获得的结果与体外实验一致。综合上述结果，得出结论：miR-506可通过靶向抑制RAD51-HR通路和EZH2-β-catenin信号转导通路，多靶点调控浆液性卵巢癌药物敏感性。本研究为揭示miR-506在浆液性OvCa中的作用和开辟新的小分子靶向治疗以增加OvCa化疗、PARP抑制剂的敏感性提供理论基础和数据支持。项目资助发表SCI论文4篇，核心论文1篇。培养硕士生4名，其中2名已经取得硕士学位，2名在读。