Dietary affects upon genomic methylation in Trout cancer

饮食对鳟鱼癌基因组甲基化的影响

• 批准号: 6898252
• 负责人: JOSEPH P BRUNELLI
• 金额: $ 13.21万
• 依托单位: WASHINGTON STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-05-28 至 2007-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6898252
• 关键词: CpG islands; DNA methylation; alternatives to animals in research; aquatic organism; carcinogenesis; dietary supplements; gene expression; gene induction /repression; genetic polymorphism; genomic imprinting; hepatocellular carcinoma; loss of heterozygosity; methylation; neuroblastoma; nucleic acid sequence; nutrient interaction; nutrition related neoplasm /cancer; nutrition related tag; polymerase chain reaction; trout /salmon

DESCRIPTION (provided by applicant): The goal of this project is to characterize the effect of dietary supplements expected to impact epigenetic methylation of genomic regions, and associate the variability in methylation to development of nephroblastomas and hepatocarcinomas through exposure to mutagens in clonal lines of rainbow trout. Trout are uniquely suited for this study because of their large size, their sensitivity to mutagens, the well developed research program exploring dietary impacts upon cancer formation, the availability of clonal lines and the ongoing development of a good comparative map in this species. Extensive evidence from studies in mammals demonstrates that the development of cancer involves epigenetic mechanisms affecting gene expression through aberrant genomic methylation. These changes to the genomic methylation status can also develop in response to dietary regimens affecting availability of biochemical substrates to metabolic pathways controlling CpG methylation. Furthermore, this process appears to include a heritable influence through a dietary impact upon the imprinting of gametes. Trout offer an opportunity to analyze, at low cost, candidate dietary elements capable of impacting cancer formation by experimentally controlling dietary variables and tumor development, in a genetically defined background of clonally derived isogenic populations. Specifically, this investigation is designed to reveal correlations between cancer incidence and dietary influences upon aberrant epigenetic CpG methylation causing gene silencing. Project objectives include: 1) Conducting genome-wide screens of CpG methylation patterns characterizing differentiated tissues recovered from isogenic juvenile trout, using the Methylation Sensitive-Amplified Fragment Length Polymorphism (MS-AFLP) technique to determine if genomic methylation patterns are influenced by dietary regimens which manipulate the availability of (folate, methionine, choline, vitamins B12, betaine and zinc). 2) Characterize nephroblastoma and hepatocarcinoma incidence and methylation polymorphisms in isogenic populations exposed to carcinogens and grown under dietary regimens demonstrated to alter methylation. 3) Analyze genome sequences of common MS-AFLP polymorphisms found in cancers, verify tumor associated methylation polymorphisms reflect physiologically relevant epigenetic events, by methylation-specific PCR and bisulfite sequencing to reveal normal tissue methylation patterns, compared to affected loci. Compare expression of genes found to be linked to tumor associated MS-AFLP sites, between normal and tumor tissues, using RT-PCR. 4) Integrate mapable diet associated MS-AFLP polymorphisms into the existing OSU x Arlee map. This investigation will provide fundamental insights into toxicological epigenetic influences through altered genomic methylation and gene expression, and allow the development of a genome-wide tissue-specific methylome profile using an experimentally tractable lower vertebrate model system. Pullman, WA 99164-4236.

描述（由申请人提供）： 该项目的目的是表征预期会影响基因组区域表观遗传甲基化的饮食补充剂的作用，并将甲基化的可变性与肾细胞瘤和肝癌的发育相关联，通过暴露于Rainbow鳟鱼的克隆线中的诱变。鳟鱼非常适合这项研究，因为它们的大小，对诱变剂的敏感性，良好的研究计划，探讨了对癌症形成的饮食影响，克隆线的可用性以及该物种中良好的比较图的持续发展。来自哺乳动物研究的大量证据表明，癌症的发展涉及通过异常基因组甲基化影响基因表达的表观遗传机制。基因组甲基化状态的这些变化也可以响应饮食方案而发展，从而影响了控制CpG甲基化的代谢途径的生化底物的可用性。此外，此过程似乎包括对配子的印迹的饮食影响，包括可遗传的影响。鳟鱼为低成本的候选饮食元素提供了一个机会，可以通过实验控制饮食变量和肿瘤发育来影响癌症的形成，这是在克隆衍生的等生群的基因背景下。具体而言，该研究旨在揭示癌症发病率与饮食对异常表观遗传CpG甲基化的影响，从而导致基因沉默。项目目标包括：1）使用甲基化敏感敏感扩增的片段长度多态性（MS-AFLP）技术来确定基因组甲基化模式是否受到饮食的影响（fitem andimine chimimination chimiention chimitional），从等生幼虫鳟鱼中恢复了分化组织的CpG甲基化模式的整个基因组筛选。甜菜碱和锌）。 2）表征肾细胞瘤和肝癌的发病率和甲基化多态性在暴露于致癌物和饮食方案下生长的同生群体中，证明会改变甲基化。 3）分析在癌症中发现的常见MS-AFLP多态性的基因组序列，验证肿瘤相关的甲基化多态性反映了通过甲基化特异性PCR和Bisulfite测序的生理相关的表观遗传事件，与受影响的地方相比，甲基化特异性PCR和Bisulfite测序以揭示正常的甲基化模式。比较使用RT-PCR，比较发现与正常组织和肿瘤组织之间的肿瘤相关的MS-AFLP位点有关的基因表达。 4）将可映射饮食相关的MS-AFLP多态性整合到现有的OSU X Arlee图中。这项研究将通过改变基因组甲基化和基因表达来对毒理学表观遗传学影响提供基本见解，并允许使用实验可触及的下脊椎动物模型系统来发展全基因组组织特异性甲基甲基谱。 Pullman，WA 99164-4236。