Persistent transcriptional changes induced by nickel through epigenetic alterations

镍通过表观遗传改变诱导持续转录变化

基本信息

批准号：
9899647
负责人：
Max Costa
金额：
$ 45.4万
依托单位：
NEW YORK UNIVERSITY SCHOOL OF MEDICINE
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-01-01 至 2024-10-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9899647
关键词：
Agar Allergic Contact Dermatitis Asthma Atmosphere Atopic Dermatitis Binding Binding Sites Bronchitis CRISPR/Cas technology Cell-Cell Adhesion Cells Characteristics Chromatin Chromatin Structure Consumption Coupled DNA Binding Development Disease Environment Epigenetic Process Epithelial Epithelial Cells Epithelium Etiology Exposure to Fibrosis Fossil Fuels Gene Activation Gene Expression Gene Expression Alteration Gene Silencing Generations Genes Genetic Transcription Goals Grant Health Health Hazards Histones Human Industrialization Long-Term Effects Lung Malignant Neoplasms Maps Mediating Medical Device Mesenchymal Methyltransferase Molecular Mus Neoplasm Metastasis Neoplastic Cell Transformation Nickel Nose Nude Mice Outcome Pathogenicity Phenotype Physical condensation Predisposing Factor Prevention Process Property Proteins Pulmonary Edema Pulmonary Fibrosis Regulation Risk Role Source Stainless Steel Structure System Testing Toxic Environmental Substances Transcription Alteration Transitional Epithelium Up-Regulation Zinc Fingers base bronchial epithelium differential expression epidemiology study epigenome functional outcomes genome-wide histone modification human disease insight knock-down medical implant novel overexpression prevent promoter transcription factor transcriptome tumor

项目摘要

Project Summary Nickel (Ni) compounds are environmental toxicants, prevalent in the atmosphere due to their use in several industrial processes, as well as extensive consumption of Ni containing products such as stainless steel, batteries, medical devices and medical implants. In addition, combustion of fossil fuels is a major source of Ni contamination in the atmosphere. Exposure to Ni is a major human health hazard, associated with a multitude of health risks including allergic contact dermatitis, bronchitis, pulmonary fibrosis, and pulmonary edema. Moreover, epidemiological studies indicate cancer development as a major outcome of Ni exposure. However, the molecular basis of Ni-induced diseases remains poorly understood. To better understand the molecular mechanisms underlying Ni-induced diseases, we investigated the effects of Ni-exposure on human epithelial cells. Our studies show that Ni-exposure-induced gene expression changes persist long after the cessation of exposure. This resulted in the cells undergoing epithelial-mesenchymal transition (EMT), and the EMT phenotype continued long after the termination of exposure. EMT is the process in which polarized epithelial cells lose cell-cell adhesion and acquire invasive and migratory mesenchymal properties. EMT is implicated in a number of diseases associated with Ni-exposure including asthma, fibrosis, cancer and metastasis. Therefore, our results suggest that persistent transcriptional changes caused by Ni exposure are likely important in the etiology of Ni-exposure associated diseases. The overarching goal of this grant is to understand the mechanisms that drive long-term transcriptional changes caused by Ni exposure. Our preliminary results suggest that Ni-exposure disrupts chromatin regulation mediated by the histone modification, H3K27me3 and the zinc finger protein, CTCF. Based on our preliminary results, we hypothesize that Ni-exposure increases chromatin accessibility through H3K27me3 loss, causing gene upregulation. CTCF binds the newly accessible chromatin and prevents H3K27me3 re-establishment after termination of Ni-exposure, thereby persistently altering gene expression. In Aim 1, we will investigate the role of H3K27me3-loss in Ni- induced persistent gene expression alterations in human lung epithelial cells. In Aim 2, we will investigate the mechanisms underlying Ni-induced persistent chromatin alterations by knocking-down CTCF and by disrupting CTCF binding sites using CRISPR/Cas9 system to examine if loss of CTCF binding could reverse Ni-induced persistent transcriptional changes. In Aim 3, we will examine the functional outcome of Ni-induced persistent transcriptional changes by investigating the tumor generating potential of Ni-exposed cells in in mice. The overall impact of our study will be the identification of the mechanisms underlying long-term transcriptional changes caused by nickel exposure, which will reveal the molecular basis of its pathogenicity, and will have major human health implications.

项目概要镍 (Ni) 化合物是环境毒物，由于其在多种用途中的使用而在大气中普遍存在。工业过程以及含镍产品的大量消耗，例如不锈钢、电池、医疗设备和医疗植入物。此外，化石燃料的燃烧是镍的主要来源大气中的污染。接触镍是对人类健康的主要危害，与许多健康风险包括过敏性接触性皮炎、支气管炎、肺纤维化和肺水肿。此外，流行病学研究表明癌症的发生是镍暴露的一个主要结果。然而，镍诱发疾病的分子基础仍知之甚少。为了更好地理解分子为了了解镍诱发疾病的机制，我们研究了镍暴露对人体上皮细胞的影响细胞。我们的研究表明，镍暴露诱导的基因表达变化在停止使用后仍持续很长时间接触。这导致细胞经历上皮间质转化（EMT），并且 EMT 表型在暴露终止后持续很长时间。 EMT是极化上皮细胞细胞失去细胞间粘附并获得侵袭性和迁移性间充质特性。 EMT 涉及与镍暴露相关的多种疾病包括哮喘、纤维化、癌症和转移。所以，我们的结果表明，镍暴露引起的持续转录变化可能在镍暴露相关疾病的病因学。这笔赠款的总体目标是了解驱动镍暴露引起的长期转录变化的机制。我们的初步结果表明 Ni 暴露会破坏由组蛋白修饰、H3K27me3 和锌介导的染色质调节手指蛋白，CTCF。根据我们的初步结果，我们假设镍暴露增加通过 H3K27me3 丢失而导致染色质可及性，导致基因上调。 CTCF新绑定染色质可接近，并防止 Ni 暴露终止后 H3K27me3 重建，从而持续改变基因表达。在目标 1 中，我们将研究 H3K27me3-loss 在 Ni- 中的作用诱导人肺上皮细胞的持续基因表达改变。在目标 2 中，我们将调查 Ni 通过敲除 CTCF 和破坏来诱导持续染色质改变的机制使用 CRISPR/Cas9 系统检查 CTCF 结合位点的 CTCF 结合丧失是否可以逆转 Ni 诱导的持续的转录变化。在目标 3 中，我们将检查 Ni 诱导的持久性功能结果通过研究小鼠中暴露于镍的细胞的肿瘤生成潜力来研究转录变化。整体我们研究的影响将是确定长期转录变化背后的机制由镍暴露引起的，这将揭示其致病性的分子基础，并将对人类产生重大影响健康影响。