CDKN2B as a Novel Epigenetically Regulated Gene in Idiopathic Pulmonary Fibrosis

CDKN2B 作为特发性肺纤维化中的新型表观遗传调控基因

• 批准号: 9247799
• 负责人: STEVEN K HUANG
• 金额: $ 37.8万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-04-01 至 2020-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9247799
• 关键词: Address; Alpha Cell; Apoptosis; Architecture; Biological; Biology; CDKN1A gene; Cardiovascular Diseases; Cell Cycle; Cell Cycle Progression; Cell Proliferation; Cells; Cicatrix; Cyclin-Dependent Kinase Inhibitor; DNA; DNA Methylation; Data; Development; Disease; Disease Pathway; Effector Cell; Epigenetic Process; Etiology; Exhibits; Extracellular Matrix; Family; Family member; Fibroblasts; Fibrosis; Future; Gene Expression; Gene Targeting; Genes; Goals; Grant; Hamman-Rich syndrome; Hypermethylation; In Vitro; Individual; Investigation; Lung; Malignant Neoplasms; Methylation; Mission; Modification; Myofibroblast; Nature; Normal tissue morphology; Pathogenesis; Pathology; Pathway interactions; Patients; Phenotype; Play; Production; Progressive Disease; Public Health; Pulmonary Fibrosis; Research; Research Personnel; Resistance; Role; Surveys; Testing; Tumor Suppressor Genes; United States National Institutes of Health; Untranslated RNA; base; cell type; epigenetic regulation; epigenomics; experimental study; genome wide association study; genome wide methylation; improved; inhibitor/antagonist; innovation; insight; knowledge base; methylation pattern; mouse model; novel; public health relevance; treatment strategy; tumor

 DESCRIPTION (provided by applicant): Although the etiology of idiopathic pulmonary fibrosis (IPF) is unknown and may involve diverse mechanisms, excessive fibroproliferation remains a central hallmark in IPF pathology. Among the many cell types that play critical roles in disease pathogenesis, fibroblasts are ultimately the effector cell of fibrosis. Fibroblasts from IPF patiens have been shown by multiple investigators to exhibit a profibrotic in vitro phenotype; these observations were often made even when cells were cultured after multiple cell passages, suggesting that epigenetic modifications may be responsible for these phenotypic changes. Through a global survey of DNA methylation patterns in IPF fibroblasts, CDKN2B was discovered to be one of the most differentially methylated genes in IPF fibroblasts. Although never previously investigated in the context of IPF, CDKN2B has been shown to be highly differentially methylated in many cancers and to regulate cell proliferation and cell cycle progression in tumors. Our objectives are to determine the mechanism by which hypermethylation and diminished CDKN2B expression contributes to the activated phenotype of IPF cells, and to understand how its expression is regulated by DNA methylation, and how methylation may be dictated by the expression and actions of a long noncoding RNA (lncRNA). Our central hypothesis is that hypermethylation of CDKN2B, driven by the lncRNA CDKN2B-antisense (AS) 1, contributes to the diminished expression of CDKN2B in IPF fibroblasts, which leads to increased myofibroblast differentiation and apoptosis resistance. This project has three specific aims: 1) Determine how diminished expression of CDKN2B contributes to a profibrotic phenotype in IPF fibroblasts; 2) Determine how DNA methylation modulates the expression of CDKN2B; and 3) Elucidate the mechanisms by which CDKN2B-AS1 contributes to the DNA hypermethylation of CDKN2B in IPF fibroblasts. The biological actions of CDKN2B in pulmonary fibrosis will be explored by examining primary fibroblasts from normal lung and patients with IPF and by mouse modeling experiments. DNA methylation analysis will be performed, and the role of lncRNAs in regulating the DNA methylation of CDKN2B will be examined. This project is innovative because it seeks to understand the function, and additionally the epigenetic regulation, of a gene that may be critical to fibroproliferation, but has never been previously investigated in IPF. Completion of these studies is expected to establish the biological importance of CDKN2B to IPF fibroblast biology, and elucidate mechanisms that regulate its expression and contribute to how differential DNA methylation patterns are established. These findings will provide not only a novel gene target for future therapy, but also advance our understanding of how DNA methylation changes arise and contribute to gene expression differences in IPF.

 描述（由申请人提供）：尽管特发性肺纤维化（IPF）的病因尚不清楚并且可能涉及多种机制，但过度的纤维增殖仍然是 IPF 病理学的中心标志。在疾病发病机制中发挥关键作用的多种细胞类型中，成纤维细胞最终是纤维化的效应细胞。多个研究人员表明，IPF 患者的成纤维细胞在体外表现出促纤维化表型；即使在多次细胞传代后培养细胞时，也经常进行这些观察，表明表观遗传修饰可能是造成这些表型变化的原因。通过对 IPF 成纤维细胞 DNA 甲基化模式的全球调查，发现 CDKN2B 是 IPF 成纤维细胞中差异最大的甲基化基因之一。尽管之前从未在 IPF 背景下进行过研究，但 CDKN2B 已被证明在许多癌症中高度差异甲基化，并调节肿瘤中的细胞增殖和细胞周期进展。我们的目标是确定高甲基化和 CDKN2B 表达减少导致 IPF 细胞激活表型的机制，并了解 DNA 甲基化如何调节其表达，以及长非编码 RNA (lncRNA) 的表达和作用如何决定甲基化。我们的中心假设是，由 lncRNA CDKN2B-反义 (AS) 1 驱动的 CDKN2B 高甲基化导致 IPF 成纤维细胞中 CDKN2B 表达减少，从而导致肌成纤维细胞分化和细胞凋亡抵抗增加。该项目有三个具体目标：1) 确定 CDKN2B 表达减少如何导致 IPF 成纤维细胞的促纤维化表型； 2) 确定DNA甲基化如何调节CDKN2B的表达； 3) 阐明CDKN2B-AS1导致IPF成纤维细胞中CDKN2B DNA高甲基化的机制。将通过检查正常肺和 IPF 患者的原代成纤维细胞以及小鼠模型实验来探索 CDKN2B 在肺纤维化中的生物学作用。将进行DNA甲基化分析，并检查lncRNA在调节CDKN2B DNA甲基化中的作用。该项目具有创新性，因为它旨在了解可能对纤维增殖至关重要的基因的功能以及表观遗传调控，但之前从未在 IPF 中进行过研究。这些研究的完成预计将确定 CDKN2B 对 IPF 成纤维细胞生物学的生物学重要性，并阐明调节其表达的机制以及有助于如何建立差异 DNA 甲基化模式的机制。这些发现不仅将为未来的治疗提供新的基因靶点，而且有助于加深我们对 DNA 甲基化变化如何产生以及如何导致 IPF 基因表达差异的理解。