Leveraging cancer-specific defects in nuclear integrity to inform novel synthetic lethal strategies

利用癌症特异性的核完整性缺陷为新型合成致死策略提供信息

• 批准号: 9886210
• 负责人: MEGAN C KING
• 金额: $ 18.22万
• 依托单位: YALE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-04-01 至 2021-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9886210
• 关键词: Animal Model; Appearance; Architecture; CRISPR interference; CRISPR screen; Cancer cell line; Cell Death; Cell Line; Cell Nucleus; Cell Survival; Cell division; Cell physiology; Cells; Cellular biology; Cessation of life; Chemicals; Chromosomes; Clustered Regularly Interspaced Short Palindromic Repeats; DNA; Defect; Development; Diagnosis; Diagnostic Neoplasm Staging; Dropout; Drug Design; Drug Screening; Essential Genes; Etiology; Exposure to; Future; Genes; Genetic; Genetic Predisposition to Disease; Goals; HCT116 Cells; Human Cell Line; Immune checkpoint inhibitor; Immune response; Immune system; Immunotherapy; Individual; Innate Immune Response; Interphase; Lamin Type A; Lead; Link; Malignant Neoplasms; Mechanics; Membrane; Modeling; Morphology; Mutation; Normal Cell; Nuclear; Nuclear Envelope; Nuclear Lamin; Oncogenic; Ontology; Pathway interactions; Proteins; Rupture; Shapes; Signal Pathway; Site; Source; Stimulator of Interferon Genes; Structure; System; Systems Biology; The Cancer Genome Atlas; Tissues; Tumor Suppressor Proteins; base; cancer cell; cancer diagnosis; cancer genetics; cell transformation; cell type; combat; effective therapy; experimental study; fitness; gene product; genome-wide; genomic data; healing; immune clearance; inhibitor/antagonist; innate immune pathways; insight; metaplastic cell transformation; neoplastic cell; new therapeutic target; novel; novel therapeutics; personalized medicine; potential biomarker; recruit; repaired; response; screening; sensor; support network; tumor; tumorigenesis

Summary Altered nuclear shape and appearance has long been known to be pathognomonic for cellular transformation; as a consequence, it is a critical parameter used in cancer diagnosis and tumor grading. Despite an increasingly mechanistic understanding of oncogenic and tumor suppressor pathways, as well as burgeoning genomic data that heralds the possibility of personalized treatments, we still lack a firm understanding of the relationship between nuclear architecture and cancer. In particular, it has yet to be defined if changes in the nucleus are causal or simply a consequence of transformation. Here, we sidestep this question, and instead ask: can the changes in nuclear architecture typical of cancer cells be exploited as a liability? Altered nuclear shape is intimately tied to mechanical defects of the nuclear envelope; recently, such defects have been linked to either transient or catastrophic losses of nuclear integrity, which can lead to cell death through two potential mechanisms. First, permanent losses of nuclear integrity are incompatible with cellular viability. Second, even transient losses of the nuclear barrier expose the DNA to cytoplasmic DNA sensors such as cGAS, which can drive a STING-dependent innate immune response that, at least in some cases, is sufficient to drive cell- autonomous death. In the latter case, loss of nuclear integrity also boosts the immune response to the tumor. Importantly, pathways that recognize and “heal” ruptures of the nuclear envelope have also been recently defined; perhaps not surprisingly, these repair mechanisms become critical for cell viability in contexts where nuclear integrity is compromised. Taken together, these new insights make a strong case that further weakening nuclear integrity in tumor cells can be exploited to drive cell death and immune system recognition. Here, in Aim 1, we propose to leverage an unbiased, genome-wide CRISPR dropout screen to identify synthetic lethal interactions of 1) normal cells with either weakened nuclear integrity or defective nuclear repair mechanisms or 2) cancer cell lines, with and without further compromise of their nuclear integrity pathways. In Aim 2, we will apply systems level approaches to organize the resulting context-dependent fitness genes into functional nodes. Beyond the strength of the genetic interaction, targets for in depth analysis will be further prioritized based on the availability of chemical inhibitors and representation in The Cancer Genome Atlas. Mechanistic experiments will explicitly examine these high priority synthetic genetic relationships in the context of nuclear shape, nuclear ruptures, and innate immune pathway activation. Completion of these two Aims will lead to the development of novel targets that exploit a key pathognomonic structure for cancer.

总结 改变的核形状和外观早已被认为是细胞转化的特异性; 因此，它是用于癌症诊断和肿瘤分级的关键参数。尽管 对致癌和肿瘤抑制途径的日益机械化的理解，以及新兴的 尽管基因组数据预示着个性化治疗的可能性，但我们仍然缺乏对基因组数据的坚定理解。 核结构与癌症的关系特别是，它还没有被定义，如果变化， 核是因果关系，或者仅仅是转化的结果。在这里，我们回避这个问题，相反， 问：癌细胞核结构的改变，会不会被当成一种负担？改变核 形状与核膜的机械缺陷密切相关;最近，这种缺陷已被联系起来 瞬时或灾难性的核完整性损失，这可能导致细胞死亡，通过两个潜在的 机制等首先，核完整性的永久丧失与细胞活力不相容。其次，即使 核屏障的瞬时丧失使DNA暴露于细胞质DNA传感器，例如cGAS，其可以 驱动依赖STING的先天免疫反应，至少在某些情况下，足以驱动细胞- 自主死亡在后一种情况下，核完整性的丧失也会增强对肿瘤的免疫反应。 重要的是，识别和“治愈”核膜破裂的途径最近也被发现。 定义;也许并不令人惊讶，这些修复机制成为细胞活力的背景下， 核完整性受损总的来说，这些新的见解使一个强有力的情况下，进一步 肿瘤细胞中核完整性的减弱可用于驱动细胞死亡和免疫系统识别。 在这里，在目标1中，我们建议利用无偏见的全基因组CRISPR缺失筛选来识别 1）正常细胞与核完整性减弱或核修复缺陷的合成致死相互作用 机制或2）癌细胞系，有或没有进一步损害其核完整性途径。在 目标2，我们将应用系统级的方法来组织产生的上下文相关的适应度基因， 功能节点除了遗传相互作用的强度，深入分析的目标将进一步 根据化学抑制剂的可用性和癌症基因组图谱中的代表性进行优先排序。 机制实验将明确检查这些高优先级的合成遗传关系的背景下， 核形状，核破裂，和先天免疫途径激活。实现这两个目标， 导致开发新的靶点，利用癌症的关键特征结构。