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: 10006509
• 负责人: Titia de Lange
• 金额: $ 101.7万
• 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/10006509
• 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; cancer genome; cancer therapy; experimental study; genome editing; genome integrity; genome sequencing; in vitro Model; innovation; insight; mouse model; new technology; p53-binding protein 1; prognostic; public health relevance; 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.

项目总结/摘要 最近的测序数据揭示了癌症中基因组不稳定性的意想不到的水平。的起源 这些变化在很大程度上是未知的。这一建议集中在两个方面的维护基因组 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 端粒肿瘤抑制途径，从而端粒磨损导致功能失调的端粒， 增殖性停滞这些实验将利用正常的人类上皮细胞， 已被CRISPR/Cas9基因组编辑删除，并将应用端粒结构的创新成像 使用超分辨率STORM成像结合扩展显微镜。当端粒肿瘤 由于p53和Rb的缺失，抑制途径失败，在早期肿瘤中端粒继续缩短 发育，导致大量功能失调的端粒和基因组不稳定（称为 端粒危象）。我们建议确定基因组中的变化，这些变化是由以下过程引起的： 端粒危象这些实验将涉及一种新的上皮细胞端粒危象体外模型 结合全基因组测序。最后，我们建议研究双链断裂的机制 (DSB)修复，这是精心调控，以保持基因组的完整性。特别是，我们将重点关注 53 BP 1抑制DSB切除并促进其移动性的机制 我们开发的模型系统和染色质结构分析（ATAC）的新技术 测序）和基因座位置（DamID-LaminB 1标记）。53 BP 1的这两个属性高度相关 由于PARP 1聚（ADP-核糖）聚合酶的抑制而导致的致死基因组不稳定性的诱导 在BRCA缺陷细胞中。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见解，最终将告知和指导 癌症诊所的决定。