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 胶质母细胞瘤多形（GBM）是成年人中最常见的恶性中枢神经系统癌。 常规治疗包括肿瘤外科切除术，然后是光子辐射与 辅助化疗导致中位存活率为14.6个月。治疗的进步已经 受GBM的极端化学和放射性的限制。组合光子和质子疗法已经 发现增加了生存时间，但是由于放射性症状而引起的并发症阻止了 该疗法方案。添加放射敏化剂可以允许使用较低的辐射剂量达到 肿瘤细胞毒性在保留正常组织的同时。该应用旨在研究硫化氢的使用 （H2S）是一种用于治疗GBM的新型放射敏化剂。 H2S已被确定为第三 内源性高递质和硫化钠（NA2S），DATS和AP39在实验中用于增加 细胞H2S。我们的初步研究表明，急性，高剂量的NA2显着诱导氧化DNA 损害并可以在培养中杀死GBM细胞系，同时避免正常的大脑内皮细胞。 NA2也发生了变化 GBM线粒体功能，蛋白质乙酰化增加，GBM细胞系中的氧化谷胱甘肽增加和 放射敏化的GBM细胞质子或光子电离辐射。我们的假设是H2S增强电离 通过增加活性氧（ROS）产生的辐射选择性杀死GBM细胞 线粒体，增强DNA损伤并导致聚（ADP-核糖）聚合酶过度激活 （PARP）。我们进一步假设PARP的过度激活会降低细胞NAD+水平，从而抑制 HDAC/ SIRTUINS，由于DNA修复的抑制和更高的DNA损伤水平导致细胞死亡。 该假设将使用两种GBM细胞系的两个目标进行测试，一个星形胶质细胞系，一个神经元细胞系 和脑微血管细胞系。 AIM 1将测试Na2s，DATS和AP39是否仅增强GBM质子 或光子电离辐射细胞杀死。我们将通过检查ROS，DNA损伤来探测该机制 生产和线粒体功能障碍。 Mitotempol，线粒体抗氧化剂和两个GBM Rho Zero 缺乏氧化磷酸化的细胞系也将用于确定是否在 线粒体。 AIM 2将测试NA2S诱导的放射敏化是否是通过PARP的过度激活和 DNA修复减少。完成这项工作后，我们将了解为什么H2S辐射敏感的GBM细胞和 知道哪种H2S释放化合物是GBM细胞的最佳放射敏剂。这可能会开放途径 用于开发H2S释放化合物作为放射增敏剂。该提案中的工作将由 毕业生，本科和高中生。这些学生将了解辐射生物学，氧化。 应力和DNA修复，并将获得对放射疗法和使用Proteus®One铅笔梁的新颖洞察力。 该建议符合R15的目标，即增强什里夫波特学生的教育。资金将大大 提高PI执行这些研究的能力，并将增强机构研究生计划。