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.

项目概要/摘要 最近的测序数据揭示了癌症中意想不到的基因组不稳定性。的起源 这些变化很大程度上是未知的。该提案重点关注基因组维护的两个方面 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 端粒肿瘤抑制途径，端粒磨损导致端粒功能失调， 增殖性逮捕。这些实验将利用正常的人类上皮细胞，其中的关键基因 已通过 CRISPR/Cas9 基因组编辑去除，并将应用端粒结构的创新成像 使用超分辨率 STORM 成像与膨胀显微镜相结合。当端粒肿瘤 由于 p53 和 Rb 的丢失，抑制途径失败，端粒在早期肿瘤期间继续缩短 发育，导致大量功能失调的端粒和基因组不稳定（称为 端粒危机）。我们建议确定因进展而导致的基因组变化 端粒危机。这些实验将涉及上皮细胞端粒危机的新体外模型 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，经过仔细调节以维持基因组完整性。我们将特别关注 53BP1 通过小鼠抑制 DSB 切除并促进其移动的机制 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）。 53BP1的这两个属性是高度相关的 由于抑制 PARP1 聚（ADP-核糖）聚合酶而诱导致命的基因组不稳定性 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，最终为人们提供信息和指导 癌症诊所的决定。