Biomarkers of formaldehyde based on DNA-protein cross-links

基于 DNA-蛋白质交联的甲醛生物标志物

• 批准号: 8747851
• 负责人: Kun Lu
• 金额: $ 7.45万
• 依托单位: UNIVERSITY OF GEORGIA
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-07-01 至 2016-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8747851
• 关键词: Animals; Archives; Biological Assay; Biological Markers; Biological Process; Cancer Etiology; Carcinogens; Cells; Chemicals; Cysteine; DNA; DNA Adducts; DNA Repair; DNA lesion; Data; Data Set; Deoxyguanosine; Detection; Distant; Dose; Electrophoresis; Environmental Pollutants; Enzymes; Exposure to; Formaldehyde; Foundations; Future; Glutathione; Goals; Heating; Human; Hydrolysis; International Agency for Research on Cancer; Laboratories; Lead; Lesion; Lysine; Malignant neoplasm of nasopharynx; Mass Spectrum Analysis; Measures; Methods; Molecular; Monitor; Nasal Epithelium; Organ; Pathway Analysis; Production; Proteins; Proteomics; Public Health; Radioactive; Reporting; Research; Risk Assessment; Testing; Time; Tissues; Toxic effect; base; cancer risk; carcinogenesis; carcinogenicity; crosslink; design; dosimetry; expectation; experience; exposed human population; innovation; leukemia; link protein; novel; programs; public health relevance; response

DESCRIPTION (provided by applicant): Formaldehyde is a widely used high production chemical that is also released as a byproduct of combustion and off-gassing of various building products. Formaldehyde has been classified as an animal and human carcinogen by the International Agency for Research on Cancer, causing nasopharyngeal cancer. Formaldehyde is also reported to be associated with the induction of leukemia. Formaldehyde is highly reactive with DNA and proteins to induce diverse lesions, with the formation of DNA-protein cross-links (DPC) as the primary genotoxic effect. Internal exposure monitoring and cancer risk assessment of formaldehyde have been challenging due to the lack of suitable biomarkers. This also limits our capability of examining formaldehyde distant effects in organs remote to nasal epithelium, which remains highly controversial. Recently, we have established N2-hydroxymethyl-deoxyguanosine as the first formaldehyde-specific DNA adduct biomarker, and the rich dataset generated using this biomarker is widely used in risk assessment of formaldehyde. However, DPC, formed at high abundance, are biologically more important because they significantly interfere with DNA repair as extremely bulky DNA lesions. However, no biomarkers have been established to quantify formaldehyde-induced DPC due to substantial technical challenges. Previous methods of measuring DPC either utilized non-chemical-specific methods with low sensitivity or relied on radioactive formaldehyde for exposure. The objective of this application is to develop biomarkers and sensitive mass spectrometry-based methods to measure formaldehyde-induced DPC. The central hypothesis is that cysteine-containing cross-links can be developed as biomarkers to quantify formaldehyde-induced DPC, and that proteins cross-linked with DNA can also serve as biomarkers to assess the formation of DPC. This hypothesis has been formulated on the basis of preliminary data produced in the applicant's laboratory and our experience on developing mass spectrometry assays for DNA lesions. We will test the hypothesis by first optimizing enzymatic hydrolysis approaches to digest DPC into small cross-links for mass spectrometry detection, and then developing sensitive mass spectrometry assays to quantify cysteine-containing cross-links. We will also isolate, identify and quantify proteins cross-linked with DNA following formaldehyde exposure as biomarkers of DPC. The approach is innovative because of the novel application of highly sensitive mass spectrometry to develop new formaldehyde-specific biomarkers to quantify DPC formation. The proposed research is significant, because it is expected to establish a set of novel biomarkers of formaldehyde exposure to measure formaldehyde- induced DPC, a current void in formaldehyde biomarker research. Results from this study will also lay a foundation for future studies aiming at establishing molecular dosimetry using these novel biomarkers of DPC to better understand formaldehyde carcinogenicity and its cancer risk assessment.

描述（由申请人提供）：甲醛是一种广泛使用的高生产化学化学物质，也被作为燃烧和各种建筑产品的燃烧性副产品释放。甲醛已被国际癌症研究机构归类为动物和人类致癌，导致鼻咽癌。据报道，甲醛还与白血病的诱导有关。甲醛与DNA和蛋白质高反应性，可诱导不同的病变，形成DNA-蛋白交联（DPC）作为主要的遗传毒性作用。由于缺乏合适的生物标志物，甲醛的内部暴露监测和癌症风险评估一直具有挑战性。这也限制了我们检查远程器官到鼻上皮的甲醛远处效应的能力，这仍然引起极大的争议。最近，我们已经建立了N2-羟基甲基 - 脱氧鸟苷作为第一个甲醛特异性DNA加合物生物标志物，并且使用该生物标志物生成的丰富数据集广泛用于甲醛的风险评估中。然而，以高丰度形成的DPC在生物学上更为重要，因为它们会显着干扰DNA修复，因为DNA修复是极大的DNA病变。但是，由于实质性的技术挑战，尚未建立生物标志物来量化甲醛诱导的DPC。先前测量DPC的方法要么使用低灵敏度的非化学特异性方法，要么依靠放射性甲醛进行暴露。该应用的目的是开发生物标志物和基于敏感的质谱方法来测量甲醛诱导的DPC。中心假设是可以作为生物标志物开发含半胱氨酸的交联，以量化甲醛诱导的DPC，并且与DNA交联的蛋白质也可以用作评估DPC形成的生物标志物。该假设是根据申请人实验室中产生的初步数据以及我们开发DNA病变质谱分析的经验提出的。我们将通过首先优化酶水解方法来检验该假设，以将DPC消化为小的交联以进行质谱检测，然后开发敏感的质谱分析，以量化含有半胱氨酸的交叉链接。在甲醛暴露后，我们还将隔离，识别和定量与DNA的蛋白质作为DPC的生物标志物。该方法具有创新性，因为高度敏感的质谱法新颖地应用了开发新甲醛特异性生物标志物来量化DPC形成。拟议的研究非常重要，因为预计它将建立一组新型的甲醛暴露生物标志物，以测量甲醛诱导的DPC，这是甲醛生物标志物研究的当前空隙。这项研究的结果还将为未来的研究奠定旨在使用这些新型DPC生物标志物建立分子剂量法的基础，以更好地了解甲醛致癌性及其癌症风险评估。