Using RNA signatures for therapy development in neurodegeneration due to C9orf72 expansions

使用 RNA 特征开发 C9orf72 扩展引起的神经退行性疾病的治疗方法

基本信息

批准号：
8817335
负责人：
Clotilde Lagier-Tourenne
金额：
$ 28.02万
依托单位：
LUDWIG INSTITUTE FOR CANCER RES LTD
依托单位国家：
美国
项目类别：
财政年份：
2014
资助国家：
美国
起止时间：
2014-09-15 至 2019-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8817335
关键词：
Affect Amyotrophic Lateral Sclerosis Antisense Oligonucleotides Binding C9ORF72 Cells Chemicals Clinical Trials Collaborations Consensus Dipeptides Disease Employee Strikes Engineering FDA approved Familial Amyotrophic Lateral Sclerosis Fibroblasts Frontotemporal Dementia Functional RNA Genes Genetic Genetic Transcription Genome Genomics High-Throughput Nucleotide Sequencing Human In Vitro Individual Link Mediating Messenger RNA Methods Molecular Profiling Motor Cortex Motor Neurons Nerve Degeneration Neurodegenerative Disorders Neurons Pathogenesis Pathway interactions Patients Pharmaceutical Preparations Play Preclinical Drug Evaluation Process Production Property Proteins RNA RNA Processing RNA Splicing RNA-Binding Proteins Reporting Role Seminal Spinal System Testing Therapeutic Toxic effect Transcript Translating Translations Work cost effective cytotoxic cytotoxicity design drug efficacy gain of function high throughput screening induced pluripotent stem cell innovation loss of function novel therapeutics public health relevance screening small molecule therapeutic development therapy development

项目摘要

DESCRIPTION (provided by applicant): RNA processing alterations are increasingly recognized to play a crucial role in the pathogenesis of a wide range of diseases including two devastating neurodegenerative conditions, amyotrophic lateral sclerosis (ALS) and frontal temporal dementia (FTD). The seminal discovery in 2011 of a hexanucleotide expansion in the C9orf72 gene as the most common cause of familial ALS and FTD significantly changed our perspective of these neurodegenerative diseases. The pathogenic mechanisms of this expansion are not yet understood. However recent lines of evidence, including from my own work, strongly support a gain of toxic property by accumulation of repeat-containing RNAs that are bidirectionally transcribed from the C9orf72 locus. Independent reports of RNA changes in fibroblasts, neurons derived from iPS cells and motor cortex from C9orf72 patients have offered evidence that RNA processing misregulation accompanies C9orf72 disease. However, it is still unresolved whether these RNA alterations are induced by the functional disruption of one or more RNA binding proteins sequestered into RNA foci or induced by another cytotoxic mechanism such as the striking accumulation of dipeptide repeat proteins translated from expanded RNAs that was recently reported in C9orf72 patients. In this project, I propose to define a set of alterations in mRNA processing that delineate a disease-dependent signature and that will serve as functional readouts to distinguish among current hypotheses for disease mechanism underlying C9orf72 ALS/FTD. By using genomic approaches optimized for precise identification of splicing and expression changes and human neurons specifically engineered to individually explore toxic mechanisms currently proposed, my group will determine which factor(s) drive the emergence of RNA processing alterations in C9orf72 disease. In particular, we will test the hypothesis that RNA alterations are induced either by sense or antisense repeat- containing RNAs. We will also use a functional screen to determine whether C9orf72-related RNA alterations are driven by reduced activity of one or more RNA binding proteins, including the proteins recently found to interact with the C9orf72 expanded repeats. Finally, my team will use the C9orf72 molecular signature to screen therapeutic compounds. Indeed, we and others have already established that antisense oligonucleotides (ASOs) targeting C9orf72 transcripts efficiently reduce pathological RNA foci in patient cells. I now propose to determine whether degradation of expanded RNAs transcribed from either the sense or antisense directions (or both), is necessary to restore RNA processing alterations linked to C9orf72 disease, an approach that may provide crucial information for the design of a clinical trial using ASOs in C9orf72 ALS/FTD patients. Disease-related RNA signatures will also serve as readouts to screen new therapeutic compounds in neurons directly derived from patient fibroblasts. Indeed, instead of using a single target RNA to determine drug efficacy, we will use quantitative analysis of a large panel of genes perturbed by C9orf72 expansions to identify small molecules that can intervene with disease-linked pathways to restore levels of the most affected RNAs.

描述（由申请人提供）：越来越多的人认识到RNA加工改变在多种疾病的发病机制中发挥着至关重要的作用，包括两种破坏性的神经退行性疾病：肌萎缩侧索硬化症（ALS）和额颞叶痴呆（FTD）。 2011 年，C9orf72 基因中的六核苷酸扩增是家族性 ALS 和 FTD 最常见原因的开创性发现，显着改变了我们对这些神经退行性疾病的看法。这种扩张的致病机制尚不清楚。然而，最近的一系列证据，包括来自我自己的工作，强烈支持通过从 C9orf72 基因座双向转录的含有重复的 RNA 的积累来获得毒性。关于 C9orf72 患者的成纤维细胞、iPS 细胞衍生的神经元和运动皮层中 RNA 变化的独立报告提供了证据，表明 RNA 加工失调伴随着 C9orf72 疾病。然而，这些 RNA 改变是否是由隔离在 RNA 焦点中的一个或多个 RNA 结合蛋白的功能破坏引起的，还是由另一种细胞毒性机制引起的，例如最近报道的从扩增的 RNA 翻译的二肽重复蛋白的显着积累，目前仍未解决。在 C9orf72 患者中。在这个项目中，我建议定义一组 mRNA 处理的改变，描绘疾病依赖性特征，并将作为功能读数来区分 C9orf72 ALS/FTD 疾病机制的当前假设。通过使用针对剪接和表达变化的精确识别而优化的基因组方法，以及专门设计用于单独探索目前提出的毒性机制的人类神经元，我的小组将确定哪些因素驱动 C9orf72 疾病中 RNA 加工改变的出现。特别是，我们将检验以下假设：RNA 改变是由含有正义或反义重复的 RNA 诱导的。我们还将使用功能筛选来确定 C9orf72 相关 RNA 改变是否是由一种或多种 RNA 结合蛋白（包括最近发现与 C9orf72 扩展重复序列相互作用的蛋白质）活性降低引起的。最后，我的团队将使用 C9orf72 分子特征来筛选治疗化合物。事实上，我们和其他人已经确定，针对 C9orf72 转录物的反义寡核苷酸 (ASO) 可以有效减少患者细胞中的病理性 RNA 病灶。我现在建议确定从有义或反义方向（或两者）转录的扩展 RNA 的降解对于恢复与 C9orf72 疾病相关的 RNA 加工改变是否是必要的，这种方法可能为临床试验的设计提供重要信息C9orf72 ALS/FTD 患者的 ASO。与疾病相关的 RNA 特征也将作为读数，在直接源自患者成纤维细胞的神经元中筛选新的治疗化合物。事实上，我们将使用对受 C9orf72 扩展扰乱的一大组基因进行定量分析来识别可以干预疾病相关途径以恢复受影响最严重的 RNA 水平的小分子，而不是使用单一靶标 RNA 来确定药物功效。