Defining the role of the EGFR in MHC expression and anti-tumor immune responses.

定义 EGFR 在 MHC 表达和抗肿瘤免疫反应中的作用。

• 批准号: 9275376
• 负责人: BRIAN P POLLACK
• 金额: --
• 依托单位: VETERANS HEALTH ADMINISTRATION
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-10-01 至 2018-09-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9275376
• 关键词: Advanced Malignant Neoplasm; Affect; Antigens; BRAF gene; Binding; Biological Assay; CD8-Positive T-Lymphocytes; Cell Line; Cell Proliferation; Cell Survival; Cells; Chromatin; Clinical; Clinical Trials; Complex; Cutaneous; Cytotoxic T-Lymphocytes; DNA; Data; Development; Down-Regulation; EGFR Protein Overexpression; Elements; Enhancers; Enzymes; Epidermal Growth Factor Receptor; Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitor; Epigenetic Process; Event; Family member; Flow Cytometry; Gene Expression; Generations; Genes; Genetic Transcription; Goals; Guidelines; Histocompatibility Antigens Class I; Homeostasis; Human; Immune; Immune Cell Activation; Immune response; Immune system; Immunologics; Immunotherapy; Inflammation; Knowledge; Link; Literature; MAP2K1 gene; MHC Class I Genes; Major Histocompatibility Complex; Major Histocompatibility Complex Gene; Malignant Neoplasms; Mediating; Methods; Mitogen-Activated Protein Kinase Inhibitor; Mitogen-Activated Protein Kinases; Modeling; Mus; Mutation; Oncogenic; Pathway interactions; Patients; Pharmaceutical Preparations; Phosphotransferases; Proteins; Publishing; RNA analysis; Recruitment Activity; Reporter; Repression; Research; Role; Signal Transduction; Site; Therapeutic; Transcriptional Regulation; Tumor Immunity; Vaccination; Veterans; adaptive immunity; base; cancer immunotherapy; cancer therapy; chemokine; chromatin immunoprecipitation; clinically relevant; combat; enzyme activity; epigenetic regulation; experimental study; immune checkpoint blockade; in vivo; inhibitor/antagonist; innovation; insight; kinase inhibitor; member; neoplastic cell; novel; novel strategies; novel therapeutics; outcome forecast; prognostic; promoter; public health relevance; response; targeted treatment; therapy development; transcription factor; tumor; tumor growth; tumor immunology; tumor microenvironment

DESCRIPTION (provided by applicant): Objectives: The main objectives of this proposal are to: (1) define how oncogenic EGFR/MAPK signal transduction influences the expression of MHC molecules and, (2) characterize the impact of therapies that target the EGFR and enzymes in the MAPK pathway on anti-tumor immune responses and the response to immunotherapy. Research Plan: In Aim 1, we will use well-characterized cell lines to model human cancers driven by EGFR over-expression, oncogenic RAS mutations, and oncogenic BRAF mutations. These cell lines will be used to determine how oncogenic EGFR/MAPK signal transduction and the medications developed to combat this signaling, impact the transcriptional and epigenetic regulation of MHC class I expression. In Aim 2, we will couple these same medications with relevant murine tumor models to determine how these medications impact in vivo immune responses to tumor challenge, the expression of relevant immune system genes, and the response to immunotherapies such as immune checkpoint blockade and therapeutic vaccination. Methods: Using the above models, we will combine EGFR, BRAFV600E, and MEK1/2 inhibitor treatment with chromatin immunoprecipitation experiments to define the impact of EGFR/MAPK signaling on the recruitment of transcription factors and the placement of epigenetic marks at the MHCI promoter. Using reporter assays, we will define regions within MHC class I promoters that are responsive to EGFR/MAPK signaling. To explore more complex regulatory mechanisms, we will investigate how EGFR/MAPK signaling impacts the function of an enhancer-blocking DNA element known to regulate MHC expression. We will also determine how EGFR/MAPK signaling impacts the recruitment/binding of CTCF, a protein that regulates MHC expression by mitigating complex chromatin interactions, to sites within the MHC. For our in vivo studies, we will use therapy- responsive and non-responsive tumor models to determine how EGFR/MAPK inhibitors impact tumor growth, the generation of tumor-reactive and antigen-specific CD8+ T cells, and the tumor microenvironment using flow cytometry, functional cytotoxic T lymphocyte (CTL) assays, RNA analysis and other approaches. We will explore the novel hypothesis that these medications have clinically relevant tumor-dependent and tumor- independent effects on host anti-tumor immunity that can be used to enhance the response to immunotherapy. Clinical Relevance: Inhibitors of the EGFR and MAPKs are already used to treat Veterans with advanced cancer with variable response rates. To help integrate these medications with new and developing therapies that are immune based, it will be crucial to have a sophisticated understanding of how these kinase inhibitors influence immune events in vivo. Indeed, despite the fact these inhibitors are already being combined with immunotherapies in clinical trials for those with advanced cancer, their impact on the immune system is largely undefined. By characterizing how these medications influence immune responses, we can develop a rational framework to optimize the use of these medications alone and in combination with immune-based therapy. In addition, by defining the mechanisms that govern EGFR/MAPK-mediated MHC repression, new approaches can be developed to disrupt the MHCI down regulation and resulting tumor cell immune escape that occurs commonly in cancer.

描述（由申请人提供）： 目的：本提案的主要目的是：（1）确定致癌EGFR/MAPK信号转导如何影响MHC分子的表达，（2）表征靶向EGFR和MAPK途径中的酶的治疗对抗肿瘤免疫应答和免疫治疗应答的影响。研究计划：在目标1中，我们将使用充分表征的细胞系来模拟由EGFR过表达、致癌RAS突变和致癌BRAF突变驱动的人类癌症。这些细胞系将用于确定致癌EGFR/MAPK信号转导和开发用于对抗这种信号转导的药物如何影响MHC I类表达的转录和表观遗传调节。在目标2中，我们将这些相同的药物与相关的小鼠肿瘤模型相结合，以确定这些药物如何影响对肿瘤攻击的体内免疫应答，相关免疫系统基因的表达以及对免疫治疗（如免疫检查点阻断和治疗性疫苗接种）的应答。研究方法：使用上述模型，我们将结合联合收割机EGFR，BRAFV 600 E，和MEK 1/2抑制剂治疗染色质免疫沉淀实验，以确定EGFR/MAPK信号转导对转录因子的募集和表观遗传标记在MHCI启动子的位置的影响。使用报告分析，我们将确定区域内的MHC I类启动子，EGFR/MAPK信号。为了探索更复杂的调控机制，我们将研究EGFR/MAPK信号传导如何影响已知调节MHC表达的增强子阻断DNA元件的功能。我们还将确定EGFR/MAPK信号传导如何影响CTCF（一种通过减轻复杂的染色质相互作用来调节MHC表达的蛋白质）与MHC内位点的募集/结合。对于我们的体内研究，我们将使用治疗应答和非应答肿瘤模型，使用流式细胞术、功能性细胞毒性T淋巴细胞（CTL）测定、RNA分析和其他方法来确定EGFR/MAPK抑制剂如何影响肿瘤生长、肿瘤反应性和抗原特异性CD 8 + T细胞的产生以及肿瘤微环境。我们将探索新的假设，即这些药物对宿主抗肿瘤免疫具有临床相关的肿瘤依赖性和肿瘤非依赖性作用，可用于增强对免疫治疗的反应。临床相关性：EGFR和MAPK抑制剂已用于治疗晚期癌症退伍军人，其缓解率各不相同。为了帮助将这些药物与基于免疫的新的和正在开发的疗法相结合，对这些激酶抑制剂如何影响体内免疫事件有一个复杂的理解将是至关重要的。事实上，尽管这些抑制剂已经在晚期癌症患者的临床试验中与免疫疗法相结合，但它们对免疫系统的影响在很大程度上是不确定的。通过描述这些药物如何影响免疫反应，我们可以开发一个合理的框架来优化这些药物单独使用以及与基于免疫的治疗相结合的使用。此外，通过定义控制EGFR/MAPK介导的MHC抑制的机制，可以开发新的方法来破坏MHC I下调和导致的肿瘤细胞免疫逃逸，这在癌症中常见。