Regulation of mitochondrial redox homeostasis and signaling in metastatic ovarian cancer

转移性卵巢癌中线粒体氧化还原稳态和信号传导的调节

• 批准号: 10617849
• 负责人: Nadine Hempel
• 金额: $ 8.94万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-07-01 至 2025-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10617849
• 关键词: AKT inhibition; Address; Anoikis; Ascites; Biochemical; Cell Adhesion; Cell Culture Techniques; Cell Line; Cell Survival; Cells; Complement; Data; Deacetylase; Environment; Epigenetic Process; Future; Genetic Transcription; Glutamine; Goals; Greater sac of peritoneum; Homeostasis; Hydrogen Peroxide; Imaging Techniques; Malignant Female Reproductive System Neoplasm; Malignant Neoplasms; Malignant neoplasm of ovary; Mediator; Metabolic; Metabolism; Metastatic Malignant Neoplasm to the Ovary; Methylation; Mitochondria; Mitochondrial Proteins; Modeling; Molecular; Monitor; Mus; Neoplasm Metastasis; Nutrient; Ovarian Clear Cell Tumor; Oxidants; Oxidation-Reduction; Oxidative Phosphorylation; PTEN gene; Pathway interactions; Patient-Focused Outcomes; Patients; Peritoneal; Phosphoric Monoester Hydrolases; Play; Proteins; Regulation; Reporting; Resistance; Role; SOD2 gene; Signal Pathway; Signal Transduction; Specimen; Stress; Stress and Coping; Superoxide Dismutase; Superoxides; Survival Rate; Testing; Therapeutic Intervention; Transcriptional Regulation; Up-Regulation; Woman; Work; Xenograft Model; antioxidant enzyme; cancer cell; clinically relevant; clinically significant; cytotoxicity; epigenetic regulation; imaging approach; improved; in vivo; inhibitor; intraperitoneal; neoplastic cell; novel; novel therapeutics; oxidation; preservation; promoter; response; sensor; spatiotemporal; therapeutic target; transcription factor; transcriptome sequencing; tumor

Late stage ovarian cancer is marked by poor patient survival and significant metastatic spread throughout the peritoneal cavity. During transcoelomic spread cells must adapt to survive anchorage-independence and to cope with stress associated with matrix detachment and the hostile environment of the ascites. Preliminary findings demonstrate that an important ovarian cancer cell adaptation during anchorage-independence is the up- regulation of two mitochondrial proteins, superoxide dismutase 2 (Sod2), and its regulator, the metabolic and redox sensing deacetylase SIRT3. Moreover, these proteins are necessary for anchorage-independent cell survival and transcoelomic metastasis in vivo. In addition to Sod2’s role as a mitochondrial superoxide scavenger, mechanistic data show that Sod2 shifts the redox landscape of cancer cells to a higher hydrogen peroxide (H2O2) steady-state. This novel non-canonical function of Sod2 as a H2O2 regulator results in mitochondrial redox signaling, as demonstrated by oxidation and inactivation of phosphatases, and enhanced Akt signaling. Preliminary data demonstrate that SIRT3 is an important regulator of Sod2 during anchorage- independence, which points to a novel pro-survival role for SIRT3 during ovarian cancer spread. Thus, the proposal will test the hypothesize that mitochondrial redox signaling is an important regulator of survival adaptations in response to matrix detachment, and that two key mitochondrial proteins, SIRT3 and Sod2, are required for the initiation and regulation of mitochondrial redox signaling in anchorage-independence. This will be addressed using a combination of cell culture models, patient ascites-derived cells, in vivo mouse xenograft models, and molecular, biochemical and imaging techniques to monitor oxidants and redox signaling. Using both unbiased screens and targeted approaches Aim 1 consists of mechanistic studies to delineate how SIRT3/Sod2- regulated mitochondrial H2O2-signaling drives anchorage-independent survival. In Aim 2 the mechanisms of SIRT3 activity and transcriptional regulation will be elucidated how SIRT3 acts as the sensor of matrix detachment in the context of metabolic changes associated with anchorage-independence. In proof-of-principle studies of Aim 3 the vulnerability of Sod2-high tumor cells will be targeted with two approaches based exploiting their sensitivity to H2O2 generating agents and Akt inhibition. Establishing that mitochondrial redox signaling is a necessary adaptation for ovarian cancer anchorage-independent survival and metastasis is crucial in our long- term goal of targeting key metastatic adaptations for novel therapies against ovarian cancer.

晚期卵巢癌的特点是患者生存率低且转移扩散严重 腹膜腔。在跨体腔传播过程中，细胞必须适应锚定独立性的生存并应对 与基质脱离和腹水恶劣环境相关的应激。初步调查结果 证明卵巢癌细胞在贴壁独立期间的一个重要适应是上行- 两种线粒体蛋白超氧化物歧化酶 2 (Sod2) 及其调节剂、代谢和代谢的调节 氧化还原传感脱乙酰酶 SIRT3。此外，这些蛋白质对于不依赖贴壁的细胞是必需的 体内存活和跨体腔转移。 Sod2 除了作为线粒体超氧化物的作用之外 清除剂，机制数据表明 Sod2 将癌细胞的氧化还原景观转变为更高的氢 过氧化物（H2O2）稳态。 Sod2 作为 H2O2 调节剂的这种新颖的非典型功能导致 线粒体氧化还原信号传导，如磷酸酶的氧化和失活所证明，并增强 Akt 信号。初步数据表明 SIRT3 是锚固过程中 Sod2 的重要调节因子 独立性，这表明 SIRT3 在卵巢癌扩散过程中具有新的促生存作用。因此， 该提案将检验线粒体氧化还原信号是生存的重要调节因子的假设 响应基质脱离的适应性，并且两个关键的线粒体蛋白 SIRT3 和 Sod2 锚定独立性中线粒体氧化还原信号的启动和调节所需的。这将 使用细胞培养模型、患者腹水来源的细胞、体内小鼠异种移植物的组合来解决这个问题 模型以及分子、生化和成像技术来监测氧化剂和氧化还原信号。两者同时使用 无偏见的筛选和有针对性的方法 目标 1 包括机制研究，以描述 SIRT3/Sod2- 受调节的线粒体 H2O2 信号传导驱动锚定非依赖性存活。在目标 2 中，机制 SIRT3活性和转录调控将阐明SIRT3如何充当基质传感器 与锚定独立相关的代谢变化背景下的脱离。原理验证 目标 3 的研究将通过两种基于利用的方法来针对高 Sod2 肿瘤细胞的脆弱性 他们对 H2O2 生成剂和 Akt 抑制的敏感性。确定线粒体氧化还原信号是 卵巢癌锚定独立生存和转移的必要适应对于我们的长期生存至关重要。 长期目标是针对卵巢癌新疗法的关键转移适应。