(PQ1) The role of cell-to-cell variation in the penetrance of heritable mutant RAS hypodermal neoplasias

(PQ1) 细胞间变异在可遗传突变 RAS 皮下肿瘤外显率中的作用

• 批准号: 10245157
• 负责人: Alexander Richard Mendenhall
• 金额: $ 36.85万
• 依托单位: UNIVERSITY OF WASHINGTON
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-09-01 至 2023-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10245157
• 关键词: Affect; Alleles; Animals; Biological; Caenorhabditis elegans; Cancer-Predisposing Gene; Cell Proliferation; Cell division; Cells; Cellular biology; Child; Clinical Trials; Costello syndrome; DNA sequencing; Data; Development; Disease; Drug Targeting; EGF gene; Environment; Epigenetic Process; Event; Fluorescence Microscopy; Gene Dosage; Gene Expression; Genes; Genetic; Genetic Screening; Genome; Genotype; Germ-Line Mutation; Goals; Heat-Shock Proteins 90; Heritability; Homologous Gene; Human; Image; Individual; Inherited; KRAS2 gene; Knowledge; Learning; Maintenance; Malignant Neoplasms; Measures; Microfluidics; Microscopy; Modeling; Modernization; Molecular; Molecular Chaperones; Mutation; Neoplasms; Noise; Noonan Syndrome; Notch and Wnt Signaling Pathway; Oncogenes; Oncogenic; Operating System; Organogenesis; Output; Pathway interactions; Patients; Penetrance; Pharmaceutical Preparations; Phenotype; Property; Proteins; RAS genes; RNA Interference; Reporter; Reporter Genes; Research; Role; Scientist; Series; Severities; Signal Transduction; Stereotyping; System; Technology; Testing; Time; Tissues; Translations; Variant; Vulva; base; biological systems; cell transformation; deviant; experience; gain of function; gain of function mutation; genome editing; innovation; light microscopy; mutant; neoplastic; novel therapeutics; programs; ras Oncogene; response; reverse genetics; transcriptome sequencing; tumor behavior

Project Summary: Our goal is to provide answers to the question: “What molecular mechanisms influence disease penetrance in individuals who inherit a cancer susceptibility gene?”. We plan to answer this question in terms of genetics and cell biology. More specifically, we plan to identify which genes influence the penetrance of RAS-driven neoplasia, and then observe how these genes alter the stereotyped program of gene expression and cell division by directly observing gene expression and cell division with quantitative light microscopy. Children with Noonan or Costello syndromes are born with mutations in RAS, the most common oncogene. Some, but not all of these individuals develop cancer. RAS-driven cancers are notoriously difficult to treat. Current anti-HSP90 clinical trials show some promise, but the drugs are toxic. We have evidence that other chaperones may be suitable targets for suppressing Ras-based cancer formation. We have evidence that the molecular mechanism that influences Ras-driven neoplasia penetrance is the epigenetically heritable ability to express more or maintain more biologically active molecules of protein per unit gene. In the proposed research, we will study isogenic C. elegans with a Ras gain of function allele that results in incompletely penetrant hypodermal neoplasia. When these animals inherit a gain of function mutation in their sole Ras homolog, let-60, just like children with Noonan syndrome, some of them will develop neoplasias. About 90% of Ras oncogene bearing worms will acquire 1-4 hypodermal neoplasias during development, in response to conserved, cancer- related EGF, Notch and WNT signaling pathways. In worms with wild-type Ras, these pathways would normally control organogenesis of the vulva. The initial manifestation of neoplasia happens reliably, at the same time during development, over and over – right when the signal for vulva development happens. We have a system wherein we know exactly where and when to look, so we can see exactly what happens in cells that may or may not become neoplastic. We will perform a reverse genetic screen to identify genes that affect neoplasia. We will watch how these genes change the series of normally well-coordinated gene expression events that cause cell proliferation and transform cell fate by measuring gene expression while it happens in living cells. Our specific central hypothesis is that animals that do develop neoplasias have epigenetic differences in chaperone expression that cause an increase in translation efficiency, resulting in a higher effective gene dosage of the Ras gain of function allele, and that in turn, results in the manifestation of neoplasia. We provide strong evidence for this hypothesis in the approach.

项目摘要：我们的目标是回答以下问题：“什么分子 影响遗传癌症易感性个体疾病外显率的机制 基因？”。我们计划从遗传学和细胞生物学的角度来回答这个问题。更具体地说， 我们计划确定哪些基因影响 RAS 驱动的肿瘤的外显率，然后 观察这些基因如何改变基因表达和细胞分裂的刻板程序 用定量光学显微镜直接观察基因表达和细胞分裂。 患有 Noonan 或 Costello 综合征的儿童出生时就带有 RAS 突变，这是最常见的突变。 常见癌基因。这些人中的一些人（但不是全部）都会患上癌症。 RAS驱动的癌症 众所周知，它们很难治疗。目前的抗 HSP90 临床试验显示出一些希望，但 药物有毒。我们有证据表明其他伴侣可能是合适的目标 抑制基于 Ras 的癌症形成。我们有证据表明分子机制 影响 Ras 驱动的肿瘤外显率的是表观遗传表达能力 每单位基因含有更多或维持更多的生物活性蛋白质分子。 在拟议的研究中，我们将研究具有 Ras 功能增益的同基因线虫 导致不完全渗透性皮下肿瘤的等位基因。当这些动物继承了 他们唯一的 Ras 同源物 let-60 获得功能突变，就像患有 Noonan 的孩子一样 综合症，其中一些会发展为肿瘤。约 90% 的蠕虫携带 Ras 癌基因 在发育过程中将获得 1-4 个皮下肿瘤，以应对保守的癌症- 相关的 EGF、Notch 和 WNT 信号通路。在具有野生型 Ras 的线虫中，这些途径 通常会控制外阴的器官发生。肿瘤的最初表现 可靠地发生，在开发过程中同时发生，一遍又一遍——就在信号出现时 因为外阴发育发生。我们有一个系统，我们可以准确地知道何时何地 观察，这样我们就可以准确地看到可能会或可能不会变成肿瘤的细胞中发生的情况。 我们将进行反向遗传筛选，以确定影响肿瘤形成的基因。我们会观看 这些基因如何改变一系列通常协调良好的基因表达事件 通过测量基因表达来引起细胞增殖并改变细胞命运 活细胞。 我们具体的中心假设是，确实发生肿瘤的动物具有表观遗传 伴侣表达的差异导致翻译效率的提高，从而导致 Ras 功能获得等位基因的有效基因剂量更高，进而导致 瘤形成的表现。我们在该方法中为这一假设提供了强有力的证据。