The Significance of Isocitrate Dehydrogenase Mutations in Gliomas

神经胶质瘤中异柠檬酸脱氢酶突变的意义

• 批准号: 8189176
• 负责人: Craig Michael Horbinski
• 金额: $ 17.16万
• 依托单位: UNIVERSITY OF KENTUCKY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-08-12 至 2016-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8189176
• 关键词: 3-methyladenine; Abbreviations; Affect; Analysis of Variance; Antioxidants; Apoptosis; Arginine; Autophagocytosis; Award; Binding Sites; Biology; Biopsy; Brain Neoplasms; Bromodeoxyuridine; Cell Death; Cell Survival; Cells; Cessation of life; Chairperson; Clinical; Codon Nucleotides; Critiques; Data; Detection; Diffuse; Environment; Enzymes; Epidermal Growth Factor Receptor; Extramural Activities; Formalin; Funding; Future; Genetic; Glioma; Gliomagenesis; Glutathione Disulfide; Goals; Green Fluorescent Proteins; Human; In Vitro; Individual; Isocitrate Dehydrogenase; Isocitrates; Kentucky; Knowledge; Laboratories; Lead; Learning; Lesion; Light; Lysosomes; MAP1 Microtubule-Associated Protein; MGMT gene; Manganese Superoxide Dismutase; Measurement; Measures; Mentors; Mentorship; Metabolic; Methods; Mus; Mutate; Mutation; NADP; Neurosciences; O(6)-Methylguanine-DNA Methyltransferase; Output; Oxidative Stress; Paraffin Embedding; Pathology; Pathway interactions; Patients; Persons; Phosphatidylethanolamine; Physicians; Point Mutation; Positioning Attribute; Primary Neoplasm; Production; Prognostic Factor; Radiation; Reactive Oxygen Species; Research; Research Personnel; Research Proposals; Resources; Scientist; Secure; Techniques; Testing; Tetrazolium; Therapeutic Intervention; Time; Tissue Model; Tissues; Training; Tumor-Derived; Universities; Work; World Health Organization; Writing; Xenograft procedure; alpha ketoglutarate; career; chemotherapy; clinically relevant; clinically significant; dichlorofluorescin; expectation; glioma cell line; improved; inhibition of autophagy; isocitrate; meetings; monodansylcadaverine; mutant; neuro-oncology; novel; outcome forecast; oxidative damage; phosphatidylethanolamine; professor; prognostic; research study; response; success; tumor

DESCRIPTION (provided by applicant): The goal of this research proposal is to determine the mechanism(s) by which mutant isocitrate dehydrogenase 1 (IDH1) causes brain tumors to be less aggressive. The most common type of brain tumor is the diffusely infiltrative glioma; these tumors cannot be completely excised surgically, and are difficult to treat with radiation and chemotherapy. Thus, infiltrative gliomas are incurable. A specific point mutation in IDH1 (and a less common analogous mutation in IDH2) has been found to be quite frequent in these gliomas. When present, it is a powerful favorable prognostic factor, being strongly associated with longer patient survival. Mutant IDH1 has recently been shown to produce a novel compound, 2-hydroxyglutarate (2-HG). However, the effects of mutant IDH1 and 2-HG on glioma cells are unknown. Other work showed that 2-HG causes oxidative stress in nonneoplastic tissue models, and our preliminary data indicate that 2-HG is toxic to glioma cells and induces autophagy, ERK activation, and reactive oxygen species production. We therefore hypothesize that the improved survival imparted by mutant IDH1 in diffuse gliomas is due to 2-HG-induced production of reactive oxygen species, leading to oxidative damage and cell death. We also hypothesize that the cell death is primarily by autophagy, a form of programmed cell death involving lysosomes that has been shown to be prominent in many gliomas. To test these hypotheses, glioma cells will be treated with 2-HG or transfected with mutant IDH1, and multiple well-described markers of autophagy and reactive oxygen species will be measured. Response of glioma cells to autophagy and reactive oxygen species modulation will be assessed. For patient-derived tumor biopsies and human-mouse xenografts, immunohistochemical markers of autophagy and oxidative stress will be quantified and correlated with IDH mutation status. Success in this project would determine whether mutant IDH1 causes increased oxidative stress and autophagy in gliomas, thereby producing a less aggressive glioma compared to tumors that are wild type for IDH1. This knowledge could then be exploited to develop novel ways of treating gliomas. I am fortunate to have been mentored by exceptional scientists and physicians, thus instilling in me a desire to pursue a career that synthesizes what I have learned as a scientist and neuropathologist.My graduate and postdoctoral work in neuroscience and my work in neuro-oncology have given me a diverse array of techniques and approaches that will be used in this project. My current position as an Assistant Professor in the Department of Pathology in the University of Kentucky offers the ideal opportunity to pursue my goal of being an independent investigator. I have nine person-months (75%) of guaranteed protected time for research, separate laboratory space that has been fully equipped, a full-time technician to increase output, and sufficient funds to conduct experiments for the next four years. All this has been put in place by my chairman, Dr. Paul Bachner, independent of my success in securing extramural funding. I also benefit from a collaborative environment, superb mentorship by Drs. Natasha Kyprianou, Arie Perry, and Jeremy Rich, and excellent technical resources. Now that I have completed my clinical training, the funding provided by this K08 award would allow me to develop as an independent investigator. Furthermore, the project described in this proposal provides a superb opportunity to discover why mutant IDH1 imparts a more favorable survival in patients afflicted with gliomas, in turn helping to identify pathways and targets for effective therapeutic interventions. PUBLIC HEALTH RELEVANCE: This research explores why mutant isocitrate dehydrogenase 1, an abnormal enzyme found in many brain tumors, is such a powerful marker of longer patient survival. Discovering why this is so will help find new ways to treat these incurable tumors. The written critiques and criteria scores of individual reviewers are provided in essentially unedited form in the "Critique" section below. Please note that these critiques and criteria scores were prepared prior to the meeting and may not have been revised subsequent to any discussions at the review meeting. The "Resume and Summary of Discussion" section above summarizes the final opinions of the committee.

描述（由申请人提供）：本研究计划的目标是确定突变异柠檬酸脱氢酶 1 (IDH1) 导致脑肿瘤侵袭性降低的机制。最常见的脑肿瘤类型是弥漫性浸润性神经胶质瘤。这些肿瘤无法通过手术完全切除，并且很难用放射和化学疗法治疗。因此，浸润性神经胶质瘤是无法治愈的。 IDH1 中的特定点突变（以及 IDH2 中不太常见的类似突变）在这些神经胶质瘤中非常常见。当它存在时，它是一个强大的有利预后因素，与较长的患者生存期密切相关。最近已证明突变 IDH1 可以产生一种新型化合物 2-羟基戊二酸 (2-HG)。然而，突变IDH1和2-HG对神经胶质瘤细胞的影响尚不清楚。其他工作表明 2-HG 在非肿瘤组织模型中引起氧化应激，我们的初步数据表明 2-HG 对神经胶质瘤细胞有毒，并诱导自噬、ERK 激活和活性氧产生。因此，我们假设突变 IDH1 在弥漫性神经胶质瘤中提高的生存率是由于 2-HG 诱导产生活性氧，导致氧化损伤和细胞死亡。我们还假设细胞死亡主要是通过自噬，这是一种涉及溶酶体的程序性细胞死亡形式，已被证明在许多神经胶质瘤中很突出。为了测试这些假设，神经胶质瘤细胞将用 2-HG 处理或用突变 IDH1 转染，并且将测量多种已知的自噬和活性氧标记物。将评估神经胶质瘤细胞对自噬和活性氧调节的反应。对于患者来源的肿瘤活检和人鼠异种移植物，将量化自噬和氧化应激的免疫组织化学标记物，并将其与 IDH 突变状态相关联。该项目的成功将确定突变的 IDH1 是否会导致神经胶质瘤中氧化应激和自噬增加，从而产生与 IDH1 野生型肿瘤相比侵袭性较低的神经胶质瘤。然后可以利用这些知识来开发治疗神经胶质瘤的新方法。我很幸运能够得到杰出科学家和医生的指导，从而向我灌输了追求综合我作为科学家和神经病理学家所学到的职业的愿望。我在神经科学方面的研究生和博士后工作以及在神经肿瘤学方面的工作给了我在这个项目中使用的各种技术和方法。我目前担任肯塔基大学病理学系助理教授，这为我实现成为一名独立研究者的目标提供了理想的机会。我有九个人月（75%）的研究保障时间、设备齐全的独立实验室空间、一名全职技术人员以提高产量，以及足够的资金在未来四年进行实验。所有这一切都是由我的主席保罗·巴赫纳博士实施的，与我成功获得外部资金无关。我还受益于协作环境以及博士的出色指导。 Natasha Kyprianou、Arie Perry 和 Jeremy Rich 以及优秀的技术资源。现在我已经完成了临床培训，K08 奖项提供的资金将使我能够发展为一名独立研究者。此外，该提案中描述的项目提供了一个绝佳的机会来发现为什么突变的 IDH1 能够使患有神经胶质瘤的患者获得更好的生存率，从而有助于确定有效治疗干预的途径和目标。 公共健康相关性：这项研究探讨了为什么突变型异柠檬酸脱氢酶 1（一种在许多脑肿瘤中发现的异常酶）是延长患者生存期的有力标志。找出原因将有助于找到治疗这些无法治愈的肿瘤的新方法。 下面的“评论”部分以基本上未经编辑的形式提供了个人评论者的书面评论和标准分数。请注意，这些批评和标准分数是在会议之前准备的，在审查会议上进行任何讨论后可能不会进行修改。上面的“讨论简历和摘要”部分总结了委员会的最终意见。