Screening for DNA damage response modulators in glioblastoma stem cells

摘要 目前还没有治愈与预后黯淡相关的高级别胶质瘤的方法。 以及糟糕的生活质量。GBM患者通常会接受手术切除，然后进行放射治疗 治疗(RT)联合烷化剂替莫唑胺(TMZ)。然而，几乎所有的GBM 患者要么对这种治疗没有反应，要么最终产生耐药性，这突显了 迫切需要有效的辅助治疗。RT和TMZ都可以通过引起肿瘤细胞 致命性DNA双链断裂，可被固有DNA识别和修复 损伤反应(DDR)从而保护细胞免受DNA损伤诱导的细胞死亡。此外，GBMS 在胶质瘤肿瘤干细胞(GSCs)的亚群中富含，其特征是 上调了DDR，这是它们具有优异的治疗耐药性的原因。靶向DNA修复 可增加/恢复脑肿瘤对TMZ和RT的敏感性，从而提高治疗效果 有效和最大限度地减少肿瘤复发。我们设计了一种快速、多功能和高度 可以检测和量化微量DNA双链断裂的灵敏记者 修复，如同源定向修复以及无同源末端连接 破坏细胞。在这里，我们建议使用这个记者来识别DNA的调节器 GSC中的损坏修复。在目标1(R61阶段)中，我们将开发和优化高通量 GSCs中DDR监测方法的筛选在目标2(R33阶段)，我们将使用该方法进行筛选 用于抑制DNA损伤修复的化合物。此项目完成后，此屏幕 应确定有效地使GSC对化疗和放射治疗敏感的新化合物 提高基因毒性疗法的疗效。

Abstract There is presently no cure for high grade gliomas which are associated with a bleak prognosis and a poor quality of life. GBM patients typically undergo surgical resection followed by radiation therapy (RT) combined with the alkylating agent temozolomide (TMZ). However, virtually all GBM patients either fail to respond to this treatment, or ultimately develop resistance, underlining the urgency for effective adjuvant therapies. Both RT and TMZ can target tumor cells by causing lethal DNA double-strand breaks, which could be recognized and repaired by the intrinsic DNA damage response (DDR) thus protecting against DNA damage-induced cell death. Further, GBMs are enriched in a subset population of glioma cancer stem cells (GSCs), characterized by an upregulated DDR which contributes to their superior therapeutic resistance. Targeting DNA repair can increase/restore sensitivity of brain tumors to TMZ and RT, thus increasing therapeutic efficacy and minimizing tumor recurrence. We have designed a rapid, versatile and highly sensitive reporter that can detect and quantify minute amounts of DNA double-strand break repairs such as homology-directed repair as well as non-homologous end joining without disrupting cells. Here we propose to use this reporter in order to identify modulators of DNA damage repair in GSCs. In Aim 1 (R61 phase), we will develop and optimize a high-throughput screening assay to monitor DDR in GSCs. In Aim 2 (R33 phase), we will use this assay to screen for compounds which inhibit DNA damage repair. Upon completion of this project, this screen should identify novel compounds which effectively sensitize GSCs to chemoradiotherapy and increase the efficacy of genotoxic therapeutics.