Hydrogen Sulfide as a Radiosensitizer for Glioblastoma

硫化氢作为胶质母细胞瘤的放射增敏剂

• 批准号: 9813138
• 负责人: LYNN HARRISON
• 金额: $ 43.57万
• 依托单位: LOUISIANA STATE UNIV HSC SHREVEPORT
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2023-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9813138
• 关键词: Accounting; Acute; Adjuvant Chemotherapy; Adoption; Adult; Aftercare; Antioxidants; Apoptosis; Astrocytes; Biological Assay; Brain; Brain Neoplasms; Breast Epithelial Cells; Cancer Biology; Carcinoma; Cell Death; Cell Line; Cell Survival; Cells; Cerebrum; Clinical Trials; Comet Assay; DNA Damage; DNA Repair; DNA Repair Inhibition; Development; Dose; Education; Endothelial Cells; Excision; Fibroblasts; Funding; Future; Gamma-H2AX; Glioblastoma; Glutathione Disulfide; Goals; High Pressure Liquid Chromatography; High School Student; Histone Deacetylase; Human; Hydrogen Sulfide; Intracranial Neoplasms; Ionizing radiation; Learning; Low Dose Radiation; Lung; Malignant - descriptor; Malignant Neoplasms; Malignant neoplasm of brain; Malignant neoplasm of central nervous system; Measurement; Measures; Mitochondria; NADH; Neurons; Normal Cell; Normal tissue morphology; Operative Surgical Procedures; Oxidative Phosphorylation; Oxidative Stress; Oxygen Consumption; Patients; Pharmaceutical Preparations; Photons; Physiological; Physiology; Plasmids; Poly(ADP-ribose) Polymerases; Primary Neoplasm; Production; Protein Acetylation; Proteins; Proteus; Protons; Quality of life; Radiation; Radiation Dose Unit; Radiation therapy; Radiation-Sensitizing Agents; Radiobiology; Radioresistance; Radiosensitization; Reactive Oxygen Species; Recurrence; Regimen; Reporter; Resolution; Role; Sirtuins; Source; Students; Testing; Therapeutic; Time; Work; anti-cancer; brain endothelial cell; brain tissue; cell killing; cell type; chemotherapy; conventional therapy; cytotoxicity; enhancing factor; fetal; improved; insight; malignant breast neoplasm; mitochondrial dysfunction; neoplastic cell; nicotinamide-beta-riboside; novel; oxidative DNA damage; prevent; programs; proton therapy; radiosensitizing; rho; sodium sulfide; standard of care; tumor; undergraduate student

ABSTRACT Glioblastoma multiforme (GBM) is the most common malignant central nervous system cancer in adults. Conventional treatment consisting of tumor surgical resection followed by photon radiation in combination with adjuvant chemotherapy results in a median survival of 14.6 months. Therapeutic advancements have been limited by the extreme chemo- and radio-resistance of GBM. Combination photon and proton therapy has been found to increase survival time, but complications due to radionecrosis have prevented the implementation of this therapy regimen. Addition of a radiosensitizing agent could allow the use of lower radiation doses to achieve tumor cytotoxicity while sparing normal tissue. This application aims to investigate the use of hydrogen sulfide (H2S) as a novel radiosensitizing agent for the treatment of GBM. H2S has been identified as the third endogenous gasotransmitter and sodium sulfide (Na2S), DATS and AP39 are used experimentally to increase cellular H2S. Our preliminary studies suggest acute, high doses of Na2S significantly induce oxidative DNA damage and can kill GBM cell lines in culture, while sparing normal cerebral endothelial cells. Na2S also altered GBM mitochondrial function, increased protein acetylation, increased oxidized glutathione in GBM cell lines and radiosensitized GBM cells to proton or photon ionizing radiation. Our hypothesis is that H2S enhances ionizing radiation-selective killing of GBM cells by increasing reactive oxygen species (ROS) production from the mitochondria, enhancing DNA damage and leading to hyper-activation of poly(ADP-ribose) polymerase (PARP). We further hypothesize that hyper-activation of PARP decreases cellular NAD+ levels, inhibiting HDAC/ sirtuins, resulting in cell death due to inhibition of DNA repair and higher DNA damage levels. This hypothesis will be tested in two aims using two GBM cell lines, an astrocyte cell line, a neuronal cell line and a cerebral microvascular cell line. Aim 1 will test whether Na2S, DATS and AP39 enhance only GBM proton or photon ionizing radiation cell killing. We will probe the mechanism by examining ROS, DNA damage production, and mitochondrial dysfunction. MitoTEMPOL, a mitochondrial antioxidant, and two GBM rho zero cell lines deficient in oxidative phosphorylation will also be used to determine if the ROS is generated in the mitochondria. Aim 2 will test whether Na2S-induced radiosensitization is through hyper-activation of PARP and reduced DNA repair. Upon completion of this work, we will understand why H2S radiosensitizes GBM cells and know which H2S-releasing compound is the best radiosensitizer of GBM cells. This will potentially open avenues for development of H2S-releasing compounds as radiosensitizers. Work in this proposal will be performed by graduate, undergraduate and high school students. These students will learn about radiation biology, oxidative stress and DNA repair and will gain novel insight into radiotherapy and the use of the Proteus®ONE pencil beam. This proposal meets the R15 goals of enhancing education of students in Shreveport. Funding will significantly improve the ability of the PI to perform these studies, and will enhance the institutional graduate program.

抽象的 多形性胶质母细胞瘤（GBM）是成人中最常见的恶性中枢神经系统癌症。 常规治疗包括肿瘤手术切除，然后结合光子辐射 辅助化疗的中位生存期为 14.6 个月。 由于 GBM 的极端化疗和放射抗性，光子和质子联合治疗已受到限制。 发现可以延长生存时间，但放射性坏死引起的并发症阻碍了实施 添加放射增敏剂可以使用较低的放射剂量来实现。 肿瘤细胞毒性，同时不影响正常组织 该应用旨在研究硫化氢的用途。 (H2S)作为治疗GBM的新型放射增敏剂已被确定为第三种。 实验上使用内源性气体递质和硫化钠 (Na2S)、DATS 和 AP39 来增加 我们的初步研究表明，急性、高剂量的 Na2S 会显着诱导 DNA 氧化。 Na2S也发生了改变 GBM 线粒体功能、GBM 细胞系中蛋白质乙酰化增加、氧化谷胱甘肽增加以及 放射敏感性 GBM 细胞对质子或光子电离辐射我们的假设是 H2S 增强了电离辐射。 通过增加GBM细胞中活性氧（ROS）的产生，对GBM细胞进行辐射选择性杀伤 线粒体、DNA 增强损伤并导致聚 (ADP-核糖) 聚合酶过度激活 (PARP)，我们进一步发现 PARP 的过度激活会降低细胞 NAD+ 水平，从而抑制 HDAC/sirtuins，由于 DNA 修复抑制和更高的 DNA 损伤水平而导致细胞死亡。 该假设将在两个目标上进行测试，使用两种 GBM 细胞系、一种星形胶质细胞系、一种神经元细胞系 脑微血管细胞系 Aim 1 将测试 Na2S、DATS 和 AP39 是否仅增强 GBM 质子。 我们将通过检查ROS、DNA损伤来探究其机制。 产生和线粒体功能障碍 MitoTEMPOL（一种线粒体抗氧化剂）和两个 GBM rho 零。 氧化磷酸化缺陷的细胞系也将用于确定 ROS 是否在细胞中产生。 目标 2 将测试 Na2S 诱导的放射增敏是否是通过 PARP 和 PARP 的过度激活来实现的。 完成这项工作后，我们将了解为什么 H2S 使 GBM 细胞放射敏感并 了解哪种释放 H2S 的化合物是 GBM 细胞最好的放射增敏剂，这可能会开辟新的途径。 该提案中的工作将由开发释放 H2S 的化合物作为放射增敏剂来完成。 这些学生将学习辐射生物学、氧化学。 压力和 DNA 修复，并将获得有关放射治疗和 Proteus®ONE 笔形束使用的新见解。 该提案满足了加强什里夫波特学生教育的 R15 目标，将显着提供资金。 提高 PI 进行这些研究的能力，并将加强机构研究生项目。