Particulate Cr(VI) Toxicology in Human Lung Epithelial Cells and Fibroblasts

人肺上皮细胞和成纤维细胞中的颗粒 Cr(VI) 毒理学

• 批准号: 8074274
• 负责人: John Pierce Wise
• 金额: $ 7.62万
• 依托单位: UNIVERSITY OF SOUTHERN MAINE
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-06-01 至 2010-09-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8074274
• 关键词: Anaphase; Arts; Biological; Biological Assay; Bypass; Cancer Etiology; Carcinogen exposure; Carcinogens; Cell Cycle; Cell Death; Cell division; Cells; Centrosome; Cessation of life; Chromates; Chromosomal Instability; Chronic; Cytogenetics; DNA Double Strand Break; Data; Epithelial Cells; Event; Exposure to; Failure; Far-Western Blotting; Fibroblasts; G2/M Arrest; Gene Expression; Genomic Instability; Goals; Growth; Human; Immunofluorescence Immunologic; Lead; Link; Lung; Lung Neoplasms; Malignant neoplasm of lung; Measures; Metals; Modeling; Molecular; Molecular Cytogenetics; Neoplastic Cell Transformation; Particulate; Phenotype; Public Health; RNA Interference; Reporting; Research; Research Proposals; Risk; Role; Spectral Karyotyping; System; Techniques; Testing; Toxicology; Western Blotting; carcinogenesis; cell growth; chromium hexavalent ion; design; interest; prevent; public health relevance; tumor; Anaphase; Arts; Biological; Biological Assay; Bypass; Cancer Etiology; Carcinogen exposure; Carcinogens; Cell Cycle; Cell Death; Cell division; Cells; Centrosome; Cessation of life; Chromates; Chromosomal Instability; Chronic; Cytogenetics; DNA Double Strand Break; Data; Epithelial Cells; Event; Exposure to; Failure; Far-Western Blotting; Fibroblasts; G2/M Arrest; Gene Expression; Genomic Instability; Goals; Growth; Human; Immunofluorescence Immunologic; Lead; Link; Lung; Lung Neoplasms; Malignant neoplasm of lung; Measures; Metals; Modeling; Molecular; Molecular Cytogenetics; Neoplastic Cell Transformation; Particulate; Phenotype; Public Health; RNA Interference; Reporting; Research; Research Proposals; Risk; Role; Spectral Karyotyping; System; Techniques; Testing; Toxicology; Western Blotting; carcinogenesis; cell growth; chromium hexavalent ion; design; interest; prevent; public health relevance; tumor

DESCRIPTION (provided by applicant): Hexavalent chromium (Cr(VI)) or chromate is a major public health concern. Chromates, particularly the insoluble compounds, are well-established human lung carcinogens. The proposed research focuses on the mechanisms of Cr(VI)-induced carcinogenesis, which are currently unknown. Recent studies indicate that particulate Cr(VI) induces chromosome instability, which is often seen in human lung tumors. However, studies of the mechanisms of Cr(VI)-induced chromosome instability have not been done. Our preliminary data show that chronic exposure to particulate Cr(VI) induces centrosome amplification and spindle assembly checkpoint bypass, and thus, the goal of this research is to understand the mechanisms that cause these events leading to Cr(VI)-induced chromosome instability and carcinogenesis. We will test the hypothesis that particulate Cr(VI) induces prolonged G2/M arrest leading to centrosome amplification and spindle assembly checkpoint bypass resulting in chromosome instability and carcinogenesis through four interrelated specific aims: 1) Demonstrate that particulate Cr(VI)-induced DNA double strand breaks cause prolonged G2/M arrest leading to centrosome amplification; 2) Identify the molecular mechanisms of how Cr(VI)-induced G2/M arrest uncouples centrosome and cell division causing centrosome amplification focusing on Mps1 and Nek2A; 3) Determine the role of Nek2A, Mad1 and Mad2 interactions in particulate Cr(VI)-induced spindle assembly checkpoint bypass; and 4) Identify those cellular and molecular phenotypic changes revealed in Specific Aims 1-3 that occur in cells that escape Cr(VI)-induced death and growth arrest and in cells that are neoplastically transformed by Cr(VI). These four aims will use a combination of established and state-of-the-art toxicological, cytogenetic, and molecular biological techniques with the following approach: 1) Cr(VI)-induced centrosome amplification and spindle assembly checkpoint bypass will be measured with immunofluorescence and cytogenetic assays; 2) Gene expression, immunolocalization and RNAi studies will be used to determine the mechanisms of centrosome amplification and checkpoint bypass ; and 3) Cell growth and neoplastic transformation assays and studies in human tumors will be used to determine the fate of cells with particulate Cr(VI)-induced chromosome instability. Results will lead to the first reports of detailed information of the interactions of Cr(VI) with centrosome duplication machinery, spindle assembly checkpoint and the first characterizations of chromosome instability in tumors from Cr(VI)-exposed workers. This research is significant because it will provide: 1) An understanding of particulate Cr(VI)'s carcinogenic mechanism; 2) Essential information to better assess the risk of exposure to particulates; and 3) A mechanistic approach for further study of Cr(VI), other metals, and lung cancer in general. PUBLIC HEALTH RELEVANCE: Hexavalent chromium (Cr(VI)) is a human lung carcinogen. These studies will advance our basic understanding of the cellular and molecular mechanisms of how cells protect against Cr(VI)-induced genomic instability. Our findings will help us design new treatments and approaches to reduce or prevent Cr(VI)-induced lung cancer and possibly other metals, which continue to be major public health concerns. Finally, we will have established a mechanistic model in a human lung cell system that will allow us to conduct studies for other factors important for preventing human lung cancer both generally and by other agents.

描述（由申请人提供）：六价铬（CR（VI））或Chromate是一个主要的公共卫生问题。铬酸盐，尤其是不溶性化合物，是建立的人类肺癌。拟议的研究重点是CR（VI）诱导的致癌作用机理，这些机制目前尚不清楚。最近的研究表明，颗粒Cr（VI）诱导染色体不稳定性，这在人类肺部肿瘤中经常可见。然而，尚未完成对CR（VI）诱导的染色体不稳定性机制的研究。我们的初步数据表明，长期暴露于颗粒CR（VI）会引起中心体扩增和主轴装配检查点旁路，因此，这项研究的目的是了解导致CR（VI）诱导的染色体不稳定性和癌变的机制。 We will test the hypothesis that particulate Cr(VI) induces prolonged G2/M arrest leading to centrosome amplification and spindle assembly checkpoint bypass resulting in chromosome instability and carcinogenesis through four interrelated specific aims: 1) Demonstrate that particulate Cr(VI)-induced DNA double strand breaks cause prolonged G2/M arrest leading to centrosome amplification; 2）确定CR（VI）诱导的G2/M停滞不合子的中心肉和细胞分裂的分子机制，导致集中的集中粒子放大，重点是MPS1和NEK2A； 3）确定NEK2A，MAD1和MAD2相互作用在颗粒CR（VI）诱导的纺锤体组件检查点旁路中的作用； 4）确定在特定目标1-3中揭示的那些细胞和分子表型变化，这些变化发生在逃避Cr（VI）诱导的死亡和生长停滞以及在CR（VI）上转化的细胞中。这四个目标将结合建立和最先进的毒理学，细胞遗传学和分子生物学技术，采用以下方法：1）CR（VI）诱导的中心体扩增和纺锤体组件旁路旁的检查点旁路，将通过免疫荧光和细胞遗传学测定进行测量； 2）基因表达，免疫定位和RNAi研究将用于确定中心体扩增的机理​​和检查点旁路； 3）细胞生长和肿瘤转化测定法和对人肿瘤的研究将用于确定细胞具有颗粒CR（VI）诱导的染色体不稳定性的命运。结果将导致第一个报告CR（VI）与中心体重复机械，主轴组装检查点的相互作用的详细信息以及来自CR（VI）暴露工人肿瘤中染色体不稳定性的首次表征。这项研究很重要，因为它将提供：1）了解颗粒Cr（VI）的致癌机制； 2）更好地评估暴露于颗粒物的风险的基本信息； 3）一种机械方法，用于进一步研究CR（VI），其他金属和肺癌。公共卫生相关性：六价铬（CR（VI））是人类肺癌。这些研究将提高我们对细胞如何预防CR（VI）诱导的基因组不稳定性的细胞和分子机制的基本理解。我们的发现将有助于我们设计新的治疗方法和方法，以减少或预防CR（VI）诱导的肺癌以及其他金属，这仍然是主要的公共卫生问题。最后，我们将在人类肺部细胞系统中建立一个机械模型，这将使​​我们能够为预防人类肺癌和其他药物的其他因素进行研究。