Genome instability in cancer: telomeres and DNA repair

癌症中的基因组不稳定性：端粒和 DNA 修复

• 批准号: 9186655
• 负责人: Titia de Lange
• 金额: $ 90.27万
• 依托单位: ROCKEFELLER UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-02 至 2023-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9186655
• 关键词: Biological Models; CRISPR/Cas technology; Cells; Chromatin Structure; Clinic; DNA Repair; Data; Development; Double Strand Break Repair; Epithelial Cells; Excision; Functional disorder; Genes; Genome; Genomic Instability; Human; Image; Maintenance; Malignant Neoplasms; Microscopy; Molecular; Pathway interactions; Poly(ADP-ribose) Polymerases; Positioning Attribute; Resolution; Structure; TP53 gene; Tumor Suppressor Proteins; XCL1 gene; base; cancer genome; cancer therapy; genome editing; genome integrity; genome sequencing; in vitro Model; innovation; insight; mouse model; new technology; p53-binding protein 1; public health relevance; research study; telomere; tumor; whole genome

PROJECT SUMMARY/ABSTRACT Recent sequencing data has revealed an unanticipated level of genomic instability in cancer. The origin of these changes is largely unknown. This proposal focuses on two aspects of the maintenance of genome integrity relevant to cancer: telomere dysfunction and DNA repair. We propose to examine the molecular basis of the telomere tumor suppressor pathway whereby telomere attrition leads to dysfunctional telomeres and proliferative arrest. These experiments will make use of normal human epithelial cells in which critical genes have been removed with CRISPR/Cas9 genome editing and will apply innovative imaging of telomere structure using super-resolution STORM imaging in combination with expansion microscopy. When the telomere tumor suppressor pathway fails because of the loss of p53 and Rb, telomeres continue to shorten during early tumor development, leading to large numbers of dysfunctional telomeres and genome instability (referred to as telomere crisis). We propose to determine the changes in the genome that result from progression through telomere crisis. These experiments will involve a new in vitro model for telomere crisis in epithelial cells combined with whole genome sequencing. Finally, we propose to study the mechanism of double-strand break (DSB) repair, which is carefully regulated to maintain genome integrity. In particular, we will focus on the mechanism by which 53BP1 represses the resection of DSBs and promotes their mobility using the mouse model systems we have developed and new technologies for the analysis of chromatin structure (ATAC sequencing) and locus position (DamID-LaminB1 marking). These two attributes of 53BP1 are highly relevant to the induction of lethal genome instability resulting from inhibition of the PARP1 poly(ADP-ribose) polymerase in BRCA-deficient cells. Collectively, the proposed experiments will illuminate new aspects of genome instability in cancer. The objective of these studies is to gain insights that will ultimately inform and guide decisions in the cancer clinic.

项目摘要/摘要 最近的测序数据显示了癌症中意外的基因组不稳定性水平。起源 这些变化在很大程度上未知。该提案重点介绍了基因组维持的两个方面 与癌症相关的完整性：端粒功能障碍和DNA修复。我们建议检查分子基础 端粒抑制途径的端粒损耗导致功能失调的端粒和 扩散逮捕。这些实验将利用正常的人类上皮细胞，其中关键基因 已使用CRISPR/CAS9基因组编辑删除，并将应用端粒结构的创新成像 结合扩展显微镜结合使用超分辨率风暴成像。当端粒肿瘤 由于p53和RB的损失，抑制器途径失败，端粒在早期肿瘤期间继续缩短 发展，导致大量功能失调的端粒和基因组不稳定性（称为 端粒危机）。我们建议确定由进展到通过的基因组的变化 端粒危机。这些实验将涉及上皮细胞中端粒危机的新体外模型 结合整个基因组测序。最后，我们建议研究双链断裂的机制 （DSB）修复，仔细调节以维持基因组完整性。特别是，我们将专注于 53BP1抑制DSB的切除并使用小鼠促进其迁移率的机制 我们开发的模型系统和用于分析染色质结构的新技术（ATAC 测序）和基因座位置（damid-laminb1标记）。这两个53BP1的属性高度相关 抑制PARP1聚（ADP-核糖）聚合酶引起的致命基因组不稳定性 在BRCA缺陷型细胞中。总的来说，拟议的实验将阐明基因组的新方面 癌症的不稳定性。这些研究的目的是获得最终告知和指导的见解 癌症诊所的决定。