Extracellular Redox Signaling in mammary tumor-fibroblast interactions

乳腺肿瘤-成纤维细胞相互作用中的细胞外氧化还原信号传导

• 批准号: 8614255
• 负责人: Melissa Lai Tee Teoh
• 金额: $ 30.43万
• 依托单位: UNIVERSITY OF NEBRASKA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8614255
• 关键词: 3-Dimensional; Adenocarcinoma Cell; Antioxidants; Attenuated; Biological; Breast Adenocarcinoma; Breast Cancer Cell; Breast Epithelial Cells; Cancer cell line; Cell Line; Cell membrane; Cell surface; Chemicals; Clinical; Coculture Techniques; DNA; Data; Development; Diagnostic Neoplasm Staging; Disease; Environment; Enzymes; Epigenetic Process; Epithelial; Epithelial Cells; Etiology; Event; Extracellular Protein; Fibroblasts; Gene Expression; Gene Silencing; Goals; Growth; Hepatocyte Growth Factor; Hydrogen Peroxide; In Vitro; Knowledge; Ligands; Malignant Neoplasms; Mammary Neoplasms; Mammary Tumorigenesis; Mammary gland; Mediating; Membrane; Methylation; Mission; Modeling; Mus; NADPH Oxidase; Neoplasm Metastasis; Non-Malignant; Normal tissue morphology; Oncogenic; Outcome; Oxidation-Reduction; Oxidative Stress; Paracrine Communication; Pathogenesis; Pathway interactions; Pharmacologic Substance; Phenotype; Phosphorylation; Prevention strategy; Production; Protein Array Analysis; Public Health; Reactive Oxygen Species; Receptor Protein-Tyrosine Kinases; Regulation; Research; Role; Sampling; Signal Transduction; Staging; Superoxide Dismutase; Superoxides; Surface; Testing; Therapeutic; Tissues; Tumor Suppressor Proteins; Work; autocrine; cancer cell; extracellular; innovation; knock-down; malignant breast neoplasm; meetings; mimetics; mouse model; mutant; neoplastic; novel; novel strategies; novel therapeutic intervention; novel therapeutics; overexpression; paracrine; prevent; promoter; protein expression; public health relevance; receptor; therapeutic target; tumor; tumor growth; tumor microenvironment; tumor progression; tumorigenesis; tumorigenic

Project Summary: There is a fundamental gap in knowledge of the role of oxidative stress in the extracellular environment in the etiology of breast cancer. Our long term goal is to elucidate the role of extracellular redox signaling in promoting mammary tumor-fibroblast interactions. Our preliminary data suggest that loss of an extracellular antioxidant enzyme, extracellular superoxide dismutase (EcSOD) is a frequent event in clinical breast cancer tissue and there is an inverse correlation between its expression and clinical stage. We also observed that re- expression of EcSOD in c-Met expressing breast cancer cells strongly attenuated oncogenic stimulation by mammary fibroblasts that overexpress the c-Met ligand, HGF. These findings led us to our hypothesis that loss of EcSOD expression contributes to breast cancer progression and metastasis through oxidative-mediated tumor-fibroblast interactions, via activating the HGF/c-Met axis. The objectives of this study are to identify the mechanisms involved in deregulating the expression of EcSOD in breast cancers and the consequences of the loss of EcSOD expression (and the resulting increase in extracellular oxidative stress) in promoting HGF/c- Met-mediated oncogenesis. We will first determine the involvement of aberrant DNA promoter methylation in regulating EcSOD gene silencing in clinical breast cancer tissues. Next, we will test a novel idea that oxidative tumor microenvironment is one of the key factors that promotes HGF/c-Met signaling. It has been well established that Hepatocyte growth factor (HGF) is often overexpressed and secreted by cancer-associated fibroblasts. This paracrine factor activates its receptor, c-Met on the surface of cancer epithelial cells. In the second aim, we will determine whether loss of EcSOD promotes tumorigenic transformation of normal mammary epithelial cells by HGF-overexpressing mammary fibroblasts. Conversely, we will evaluate whether re-expression of EcSOD in breast cancer cells will attenuate oncogenic stimulation induced by fibroblast- derived HGF. We will further examine whether NADPH oxidase-generated oxidative stress on the plasma membrane is involved in HGF/c-Met activation. We will utilize a 3-dimensional co-culture model that includes both the cancer epithelial cells and their oncogenic 'partner', fibroblasts. In addition to determining the tumorigenic stimulation of fibroblasts on cancer epithelial cells, we will also examine how cancer cells reciprocally alter the phenotype of fibroblasts. We will next investigate the effects of EcSOD on tumor growth and metastasis of c-Met expressing breast cancer cells using a syngeneic mouse model as well as using an orthotopic tumor-fibroblast model. Overall, our multi-pronged study will utilize overexpression, knock-down, inactive mutant protein expression, pharmaceutical SOD mimetic and chemical inhibition approaches to validate the role of extracellular oxidative stress in promoting progression and metastasis of breast cancer. Positive outcome will help in expanding our understanding of the role of extracellular oxidative stress in fueling cancer epithelial-fibroblast interactions, towards development of novel therapeutic interventions.

项目摘要： 对于氧化应激在细胞外环境中的作用， 乳腺癌的病因。我们的长期目标是阐明细胞外氧化还原信号在细胞内的作用。 促进乳腺肿瘤-成纤维细胞相互作用。我们的初步数据表明，细胞外 抗氧化酶，细胞外超氧化物歧化酶（EcSOD）是临床乳腺癌中常见的事件 组织中，其表达与临床分期呈负相关。我们也注意到， 表达c-Met的乳腺癌细胞中EcSOD的表达强烈减弱了 过表达c-Met配体HGF的乳腺成纤维细胞。这些发现使我们假设， EcSOD的表达通过氧化介导的细胞因子介导乳腺癌的进展和转移 肿瘤-成纤维细胞相互作用，通过激活HGF/c-Met轴。本研究的目的是确定 乳腺癌中EcSOD表达失调的机制以及 EcSOD表达的丧失（以及导致的细胞外氧化应激的增加）在促进HGF/c- Met介导的肿瘤发生。我们将首先确定异常DNA启动子甲基化是否参与了 调节临床乳腺癌组织中EcSOD基因沉默。接下来，我们将测试一个新的想法， 肿瘤微环境是促进HGF/c-Met信号传导的关键因素之一。已经充分 肝细胞生长因子（HGF）通常由癌症相关的细胞过度表达和分泌， 成纤维细胞这种旁分泌因子激活癌上皮细胞表面的受体c-Met。在 第二个目的，我们将确定EcSOD的缺失是否会促进正常人的肿瘤转化。 乳腺上皮细胞通过HGF过表达的乳腺成纤维细胞。相反，我们将评估是否 EcSOD在乳腺癌细胞中的重新表达将减弱成纤维细胞诱导的致癌刺激， 衍生的HGF我们将进一步研究NADPH氧化酶是否对血浆产生氧化应激 膜参与HGF/c-Met活化。我们将利用三维共培养模型，包括 癌上皮细胞和它们的致癌“伙伴”成纤维细胞。除了确定 成纤维细胞对癌上皮细胞的致瘤刺激，我们还将研究癌细胞如何 改变成纤维细胞的表型。我们接下来将研究EcSOD对肿瘤生长的影响 和转移的c-Met表达乳腺癌细胞使用同系小鼠模型以及使用 原位肿瘤成纤维细胞模型。总的来说，我们的多管齐下的研究将利用过表达，敲低， 失活突变蛋白表达、药物SOD模拟物和化学抑制方法， 验证细胞外氧化应激在促进乳腺癌进展和转移中的作用。 积极的结果将有助于扩大我们对细胞外氧化应激在燃料中的作用的理解。 癌症上皮-成纤维细胞相互作用，以开发新的治疗干预措施。