Targeting IDH mutations to improve seizure control in glioma patients

针对 IDH 突变改善神经胶质瘤患者的癫痫发作控制

• 批准号: 10044076
• 负责人: Craig Michael Horbinski
• 金额: $ 43.89万
• 依托单位: NORTHWESTERN UNIVERSITY AT CHICAGO
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-08-01 至 2025-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10044076
• 关键词: Address; Adult; Affect; Agonist; Alzheimer' s Disease; Antiepileptic Agents; Anxiety; Behavior; Binding; Brain; Brain Neoplasms; Cells; Characteristics; Chemicals; Clinical; Clinical Trials; DNA Sequence Alteration; Data; Diffuse; Disease; Electroencephalography; Engineering; Enzyme Inhibitor Drugs; Epilepsy; Excitatory Amino Acid Transporter 2; Extracellular Space; Fostering; Generations; Genes; Genomics; Genotype; Glioblastoma; Glioma; Glutamate Transporter; Glutamates; Hippocampus (Brain); Immunohistochemistry; In Vitro; Incidence; Inflammation; Isocitrate Dehydrogenase; Keppra; Lead; Left; Levetiracetam; Life; Light; Link; Mass Spectrum Analysis; Memantine; Membrane; Memory Loss; Metabolic; Methods; Molecular; Mus; Mutation; N-Methyl-D-Aspartate Receptors; NMDA receptor antagonist; Neurologic; Neurons; Neurotransmitters; Oranges; Oxidative Stress; Pathologic; Patients; Pharmaceutical Preparations; Pharmacology; Preparation; Primary Brain Neoplasms; Production; Proteomics; Publishing; Quality of life; Receptor Inhibition; Risk; Seizures; Sleeping Beauty; Slice; Structure; Synapses; Synaptic Cleft; Testing; Time; Tissues; Transposase; United States; Ursidae Family; Work; World Health Organization; analog; base; brain tissue; excitatory amino acid transporter 3; excitotoxicity; experience; improved; in vivo; inhibitor/antagonist; multi-electrode arrays; neuron loss; new therapeutic target; next generation; patch clamp; patient population; prevent; receptor; receptor downregulation; relating to nervous system; reuptake; side effect; success; transcriptome sequencing; tumor

PROJECT SUMMARY Diffusely infiltrative glioma is the most common primary brain tumor in adults. Most glioma patients experience at least one seizure during the course of their disease, and over 30% suffer from repeated seizures, known as tumor-associated epilepsy (TAE). Current front-line treatment for TAE is levetiracetam (LEV) (a.k.a. Keppra®), but this fails to control seizures in over 50% of patients. Such patients then require more powerful second-line antiepileptic drugs that often have greater side effects. TAE is more common in World Health Organization (WHO) grade II-III gliomas than in grade IV glioblastomas, but the reason for this is not clear. The vast majority of grade II-III gliomas contain mutations in isocitrate dehydrogenases 1 and 2 (collectively “IDHmut”), which lead to the production and release of large amounts of D-2-hydroxyglutarate (D2HG). D2HG bears a great deal of structural similarity to glutamate, an excitatory neurotransmitter that binds to N-methyl-D-aspartate receptor (NMDAR) on neurons. Our data show that D2HG increases in vitro neuronal membrane depolarization and neuronal network activity, and that this can be completely blocked by an NMDA receptor (NMDAR) antagonist. We also found that IDHmut glioma increases seizure activity in engrafted mice compared to IDHwt glioma, and that this is greatly reduced by treatment with IDHmut enzyme inhibitor. Finally, we found that IDHmut gliomas are much more likely to cause seizures compared to IDHwt gliomas. This is the first direct evidence of a mechanistic link between IDHmut and seizures; therefore, our hypothesis is that D2HG contributes to an increased incidence of seizures in patients with IDHmut gliomas, and that new targeted therapeutic strategies can decrease seizures in these patients. In Aim 1, we will explore the mechanisms by which D2HG triggers neuronal depolarization and increased neuronal network activity. Our two main hypotheses are: (i) D2HG directly stimulates NMDA receptors; (ii) D2HG inhibits glutamate reuptake transporters that normally prevent the pathologic accumulation of glutamate in the synaptic cleft. We will use patch clamping and multi-electrode arrays to study the effects of D2HG on the electrical activity of cultured mouse cortical neurons, as well as on mouse brain slices. In Aim 2, we will explore the effects of IDHmut glioma on the surrounding nonneoplastic tissue in vivo, focusing on changes that are characteristic of epilepsy, including neuronal loss, NMDAR downregulation, oxidative stress, inflammation, hippocampal damage, and altered mouse behavior. Results will be validated in patient-derived IDHwt and IDHmut gliomas. In Aim 3, we will compare the anti-seizure effects of two next- generation IDHmut inhibitors, AG-120 and AG-881, as well as memantine, an NMDAR antagonist that is already used to treat Alzheimer’s Disease. Each of these drugs will be tested as monotherapy and in combination with LEV. Successful completion of these Aims will establish the D2HG product of IDHmut as an epileptogenic agent, will shed more light on how IDHmut alters the nonneoplastic neural tissues surrounding glioma, and will foster clinical trials to determine the efficacy of IDHmut inhibitors, and memantine, against seizures in these patients.

项目概要 弥漫浸润性神经胶质瘤是大多数神经胶质瘤患者最常见的原发性脑肿瘤。 患病期间至少有一次癫痫发作，超过 30% 的人会反复癫痫发作，称为 肿瘤相关癫痫 (TAE)。目前 TAE 的一线治疗方法是左乙拉西坦 (LEV)（又名 Keppra®）， 但这无法控制超过 50% 的患者的癫痫发作，因此需要更强大的二线治疗。 抗癫痫药物往往具有较大的副作用，TAE在世界卫生组织中更为常见。 (WHO) II-III 级胶质瘤高于 IV 级胶质母细胞瘤，但绝大多数的原因尚不清楚。 的 II-III 级神经胶质瘤含有异柠檬酸脱氢酶 1 和 2 的突变（统称为“IDHmut”），这导致 大量 D-2-羟基戊二酸 (D2HG) 的产生和释放具有很大的影响。 与谷氨酸的结构相似，谷氨酸是一种与 N-甲基-D-天冬氨酸受体结合的兴奋性神经递质 (NMDAR) 对神经元的影响我们的数据表明 D2HG 增加了体外神经元膜去极化和 神经元网络活动，并且可以被 NMDA 受体 (NMDAR) 拮抗剂完全阻断。 我们还发现，与 IDHwt 神经胶质瘤相比，IDHmut 神经胶质瘤增加了移植小鼠的癫痫发作活动，并且 通过 IDHmut 酶抑制剂治疗可以大大减少这种情况。最后，我们发现 IDHmut 神经胶质瘤是有效的。 与 IDHwt 神经胶质瘤相比，它更容易引起癫痫发作，这是机制的第一个直接证据。 IDHmut 与癫痫发作之间存在联系；因此，我们的假设是 D2HG 会导致癫痫发作增加 IDHmut 神经胶质瘤患者癫痫发作的发生率，新的靶向治疗策略可以 在目标 1 中，我们将探讨 D2HG 触发的机制。 我们的两个主要假设是：(i) D2HG 直接作用。 刺激 NMDA 受体；(ii) D2HG 抑制谷氨酸再摄取转运蛋白，该转运蛋白通常会阻止 谷氨酸在突触间隙的病理性积累我们将使用膜片钳和多电极阵列。 研究 D2HG 对培养的小鼠皮质神经元以及小鼠的电活动的影响 在目标 2 中，我们将探讨 IDHmut 胶质瘤对周围非肿瘤组织的影响。 体内，重点关注癫痫特征的变化，包括神经元损失、NMDAR 下调、 氧化应激、炎症、海马损伤和小鼠行为改变的结果将在中得到验证。 患者来源的 IDHwt 和 IDHmut 神经胶质瘤 在目标 3 中，我们将比较两种接下来的抗癫痫效果。 第二代 IDHmut 抑制剂 AG-120 和 AG-881，以及美金刚（一种 NMDAR 拮抗剂） 用于治疗阿尔茨海默病的每种药物都将作为单一疗法和联合疗法进行测试。 LEV 的成功完成将使 IDHmut 的 D2HG 产品成为致癫痫剂， 将进一步阐明 IDHmut 如何改变神经胶质瘤周围的非肿瘤性神经组织，并将促进 确定 IDHmut 抑制剂和美金刚对这些患者癫痫发作的疗效的临床试验。