MEG3 deletion drives lung tumorigenesis due to environmental nickel exposure

由于环境镍暴露，MEG3 缺失导致肺部肿瘤发生

基本信息

批准号：
10579842
负责人：
Max Costa
金额：
$ 54.87万
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：
2019
资助国家：
美国
起止时间：
2019-04-01 至 2025-03-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10579842
关键词：
Affect Automobile Driving Biological Biological Assay CRISPR/Cas technology Cancer Patient Carcinogens Cell Culture Techniques Cells Clinical Development Down-Regulation Epigenetic Process Epithelial Cells Event Exposure to Gene Expression Regulation Genes Goals Human In Vitro Individual Inhalation International Agency for Research on Cancer Knockout Mice Knowledge Laboratory Study Lung Lung Neoplasms Malignant - descriptor Malignant neoplasm of lung Mediating Mediator Modeling Molecular Mus Nickel Nude Mice Oncogenes Oncogenic Outcome Oxidative Stress Play Pollution Prevention Prognostic Marker Reporting Research Role Signal Pathway Signal Transduction Structure of parenchyma of lung System Testing Time Tissues Transducers Tumor Suppressor Genes Tumorigenicity Untranslated RNA Up-Regulation Xenobiotics attenuation bronchial epithelium c-myc Genes cancer classification carcinogenicity cell transformation deep sequencing design epidemiology study experimental study gain of function improved in vivo insight knock-down loss of function lung carcinogenesis lung tumorigenesis mouse model new therapeutic target novel overexpression professional atmosphere small hairpin RNA therapeutic target

项目摘要

Abstract Decades of both epidemiological research and in vitro and in vivo laboratory studies have consistently reported an association between environmental nickel exposure and lung cancer. As early as 1990, the International Agency for Research on Cancer (IARC) classified nickel compounds as Group 1 carcinogens: substances confirmed as carcinogenic to humans. Although the multiple mechanisms, including oxidative stress, epigenetic effects, and activation of signaling pathways that trigger differential gene regulation has been thought to be associated with nickel carcinogenic effect, there is no evidence that a single nickel- inducible factor can drive transformation of human bronchial cells, to the best of our knowledge. In our Preliminary Studies, we performed long noncoding RNA (lncRNA) deep sequencing using the Illumina HiSeqTM2000/2500 high throughout system to evaluate whether nickel affects the abundance of 5,929 known lncRNAs. Nickel treatment altered the levels of 24 of these lncRNAs in normal primary human bronchial epithelial cells (HBECs), while 16 of them were verified in Real-time PCR assay. With overexpression and/or knockdown analyses of the 16 lncRNAs, we further discovered that a reduced abundance of maternally-expressed gene 3 (MEG3) was sufficient for malignant transformation of HBECs. Our demonstration that MEG3 inhibition can independently transform HBECs provides the basis of our central hypothesis that MEG3 downregulation drives transformation and tumorigenecity of HBECs after nickel exposure. Here we propose to elucidate the molecular mechanisms that underlie our novel findings that MEG3 downregulation is a crucial driver for nickel-induced malignant transformation of HBECs with the following Specific Aims: 1, To test the hypothesis that p62 and C-Myc define an important MEG3-regulated axis that promotes transformation of HBECs upon MEG3 deficiency; 2, To test the hypothesis that the crosstalk between a p62/C-Myc cascade and the PHLPP/HIF-1α axis causes the MEG3-deficiency- correlated malignant transformation of HBECs; 3, To explore the biological significance of MEG3 deletion and its activated downstream molecules in lung tumoriginecity. Our novel Preliminary Findings suggest that MEG3 is downregulated by nickel exposure both in vitro and in vivo, that knockdown of MEG3 alone can transform HBECs, and that crosstalk between the putative signaling transducers downstream of MEG3 mediate the malignant transformation of HBECs caused by MEG3 deficiency. This proposal's strengths are the complementary use of cell culture models and novel conditional MEG3 knockout mouse models to examine integration of the molecular events that account for nickel-mediated lung carcinogenesis. Clarifying these issues will provide valuable insights regarding MEG3 as a prognostic biomarker and/or as a therapeutic target. Ultimately, both uses could improve clinical outcomes in lung cancer patients.

抽象的数十年的流行病学研究以及体外和体内实验室研究一致表明早在 1990 年，研究人员就报道了环境镍暴露与肺癌之间的关联。国际癌症研究机构 (IARC) 将镍化合物列为第 1 类致癌物：物质被证实对人类具有致癌性，虽然有多种机制，包括氧化作用。应激、表观遗传效应和触发差异基因调控的信号通路激活被认为与镍的致癌作用有关，但没有证据表明单一的镍- 据我们所知，诱导因子可以驱动人类支气管细胞的转化。初步研究，我们使用 Illumina 进行了长非编码 RNA (lncRNA) 深度测序 HiSeqTM2000/2500高通量系统评估镍是否影响5,929的丰度已知的 lncRNA 治疗改变了正常原代人类中 24 种 lncRNA 的水平。支气管上皮细胞（HBEC），其中 16 个在实时 PCR 检测中得到验证。通过对 16 个 lncRNA 的过表达和/或敲低分析，我们进一步发现减少的母源表达基因 3 (MEG3) 的丰度足以引起 HBEC 的恶性转化。我们证明 MEG3 抑制可以独立地转化 HBEC，这为我们的研究奠定了基础中心假设是 MEG3 下调驱动 HBEC 的转化和致瘤性在这里，我们建议阐明我们的新发现背后的分子机制。 MEG3 下调是镍诱导 HBEC 恶性转化的关键驱动因素具体目标如下： 1，检验 p62 和 C-Myc 定义重要的 MEG3 调节的假设 MEG3 缺乏时促进 HBEC 转化的轴 2，检验以下假设： p62/C-Myc 级联和 PHLPP/HIF-1α 轴之间的串扰导致 MEG3 缺乏 3、探讨MEG3缺失的生物学意义；及其在肺肿瘤发生中激活的下游分子。我们的新初步研究结果表明： MEG3 在体外和体内均因镍暴露而下调，仅敲除 MEG3 即可转换 HBEC，以及 MEG3 下游假定信号转导器之间的串扰介导由 MEG3 缺乏引起的 HBEC 的恶性转化。该提案的优点是。细胞培养模型和新型条件性 MEG3 敲除小鼠模型的互补使用检查导致镍介导的肺癌发生的分子事件的整合。澄清这些问题将为 MEG3 作为预后生物标志物和/或作为最终，这两种用途都可以改善肺癌患者的临床结果。