METTL3 in chromium-induced angiogenesis and carcinogenesis

METTL3 在铬诱导的血管生成和癌变中的作用

• 批准号: 10615806
• 负责人: STEVEN B. MCMAHON
• 金额: $ 51.95万
• 依托单位: THOMAS JEFFERSON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-04-29 至 2027-01-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10615806
• 关键词: Adenosine; Animal Model; Biological Assay; Biological Markers; Blood; Blood specimen; CRISPR/Cas technology; CXCL5 gene; Cell Proliferation; Cells; Chromates; Chromium; Chronic; Development; Dose; Endothelial Cells; Environmental Carcinogens; Enzyme-Linked Immunosorbent Assay; Enzymes; Epithelial Cells; Exposure to; Future; Gene Chips; Goals; Hypoxia Inducible Factor; IL8 gene; IL8RA gene; Interleukin 8A Receptor; Knock-out; Lung; Malignant - descriptor; Malignant Neoplasms; Malignant neoplasm of lung; Mediating; Messenger RNA; Metal exposure; Methylation; Methyltransferase; Modeling; Modification; Molecular; Mononuclear; Mus; Occupational Exposure; Peripheral Blood Mononuclear Cell; Play; RNA; RNA Interference; Role; SOX4 gene; Sampling; Signal Pathway; Signal Transduction; Structure of parenchyma of lung; Techniques; Testing; Tissue Sample; Tube; Tumor Angiogenesis; Up-Regulation; Vascular Endothelial Cell; angiogenesis; cancer prevention; cancer type; carcinogenesis; cell transformation; chemokine; chromium hexavalent ion; disorder prevention; early detection biomarkers; epidemiology study; exposed human population; human subject; hypoxia inducible factor 1; interest; non-smoking; novel; overexpression; paracrine; posttranscriptional; receptor; transcription factor; tumor; tumor growth; tumorigenesis; whole genome

Exposure of hexavalent chromium [Cr(VI)] is known to induce lung cancer. Although there is emerging interest in mechanisms of Cr(VI)-induced carcinogenesis, role of Cr(VI) in inducing RNA modification in carcinogenesis is unknown. Our preliminary studies found that higher levels of methyltransferase like 3 (METTL3) were found in lung tissues from Cr(VI)-exposed mice, samples from Cr(VI)-exposed nonsmoking workers, and Cr(VI)- transformed (Cr-T) cells. To study underlying mechanism, we found that METTL3 was induced by upregulation of Nrf2 and SOX4, two important transcription factors. We found that METTL3 was important in regulating Cr-T cell proliferation, tube formation and tumor angiogenesis. METTL3 induced hypoxia-inducible factor 1 (HIF- 1) expression through suppressing PHD2, suggesting METTL3/PHD2/HIF-1 signaling would be important in Cr(VI) carcinogenesis. C-X-C motif chemokine 5 (CXCL5) and IL-8 were downstream effectors of METTL3. Our whole genome expression array analysis of blood mononuclear cells (PBMCs) from Cr(VI)-exposed nonsmoking workers and control subjects showed that METTL3, CXCL5 and IL-8 were among the most upregulated molecules in Cr(VI) exposure group, which was validated using RT-qPCR and ELISA assays. We hypothesize that long-term Cr(VI) exposure induces METTLE3 overexpression to regulate cell transformation, tumor growth and angiogenesis through METTL3/PHD2/HIF-1 axis in lung epithelial cells, and SOX4 and NRF-2 are two key upstream inducers. In order to test this hypothesis, we will perform three specific aims: Aim 1) To determine role and mechanism of METTL3 upregulation in Cr(VI)-induced cell transformation, tumor growth and angiogenesis, and to identify upstream regulator(s) of METTL3 elevation in Cr-T cells. Aim 2) To investigate key downstream targets and molecules of METTL3 in Cr(VI)-induced cell transformation and tumor growth. Aim 3) To determine whether METTL3 upregulation in Cr-T cells induces tumor angiogenesis through CXCR1/2 receptors and paracrine effect using humanized chimeric tumor model; to determine expression levels of Nrf2, SOX4, METTL3, PHD2, HIF-1, CXCL5, and/or IL-8 in peripheral blood mononuclear cells (PBMCs) and lung tissues from the Cr(VI)-exposed mice and in PBMCs from workers with occupational exposure to Cr(VI). We will use a combination of molecular approaches, animal models, and blood and tissue samples from human subjects and mice to define the role and mechanisms of new METTL3/PDH2/HIF-1 axis induced by Nrf2 and SOX4 in mediating cell transformation, tumor growth and angiogenesis, and determine the possible correlations with Cr(VI) internal exposure doses in workers and in mice via levels of these molecules. We will also investigate the effects of downstream effectors of METTL3/PDH2/HIF-1 axis, and their receptors in Cr-T cell-inducing angiogenesis. These studies will help us understand underlying mechanisms of Cr(VI) in inducing tumor growth and angiogenesis, and identify new biomarkers for early detection of Cr(VI) exposure and cancer prevention.

已知六价铬[CR（VI）]的暴露会诱导肺癌。虽然有新兴的兴趣 在Cr（VI）诱导的癌变的机理中，Cr（VI）在诱导RNA修饰中的作用在癌变中 是未知的。我们的初步研究发现，发现较高水平的甲基转移酶（例如3（mettl3）） 在CR（VI）暴露小鼠的肺组织中 转化的（CR-T）细胞。为了研究潜在机制，我们发现Mettl3是由上调诱导的 NRF2和SOX4，这是两个重要的转录因子。我们发现METTL3对于调节CR-T很重要 细胞增殖，管形成和肿瘤血管生成。 METTL3诱导低氧诱导因子1（HIF- 1）通过抑制phd2的表达，建议Mettl3/phd2/hif-1信号在 CR（VI）癌变。 C-X-C基序趋化因子5（CXCL5）和IL-8是Mettl3的下游效应。 我们对CR（VI）暴露的血液单核细胞（PBMC）的整个基因组表达阵列分析 非吸烟工人和控制对象表明，Mettl3，CXCL5和IL-8是最多的 CR（VI）暴露组的分子上调，该分子使用RT-QPCR和ELISA分析进行了验证。我们 假设长期CR（VI）暴露会诱导Mettle3过表达来调节细胞 通过肺上皮中的mettl3/phd2/hif-1轴的转化，肿瘤生长和血管生成 细胞，SOX4和NRF-2是两个关键的上游诱导剂。为了检验这一假设，我们将执行 三个具体目的：目标1）确定Cr（VI）诱导的细胞中Mettl3上调的作用和机制 转化，肿瘤生长和血管生成，并确定Mettl3升高的上游调节剂 CR-T细胞。目标2）研究CR（VI）诱导的细胞中Mettl3的键下游靶标和分子 转化和肿瘤生长。目标3）确定CR-T细胞中的METTL3上调是否诱导 通过人构化嵌合肿瘤模型，通过CXCR1/2受体和旁分泌作用的肿瘤血管生成； 确定NRF2，Sox4，Mettl3，Phd2，Hif-1，CxCl5和/或IL-8的表达水平 外周血单核细胞（PBMC）和来自CR（VI）暴露的小鼠的肺组织，并在 来自职业接触CR（VI）的工人的PBMC。我们将结合分子 来自人类受试者和小鼠的方法，动物模型以及血液和组织样本来定义角色 NRF2和SOX4在中介细胞中诱导的新METTL3/PDH2/HIF-1轴的机制和机制 转化，肿瘤生长和血管生成，并确定与CR（VI）内部的可能相关性 通过这些分子的水平，工人和小鼠的暴露剂量。我们还将研究 METTL3/PDH2/HIF-1轴的下游效应及其受体在CR-T细胞诱导的血管生成中。 这些研究将帮助我们了解诱导肿瘤生长和 血管生成，并确定新的生物标志物，用于早期检测CR（VI）暴露和预防癌症。