Targeting cysteine import to induce ferroptotic cell death in pancreatic cancer

靶向半胱氨酸输入诱导胰腺癌铁死亡细胞

• 批准号: 10590731
• 负责人: Kenneth P Olive
• 金额: $ 39.79万
• 依托单位: COLUMBIA UNIVERSITY HEALTH SCIENCES
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-03-08 至 2027-02-28
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10590731
• 关键词: 4' -phosphopantetheine; Acute; Alleles; Amino Acids; Antioxidants; Autophagocytosis; Basic Science; Biochemical; Cancer Etiology; Cell Death; Cell Line; Cells; Cellular Membrane; Cessation of life; Chemistry; Coenzyme A; Cyst; Cysteine; Cystine; Cytotoxic Chemotherapy; Data; Detoxification Process; Diet; Disulfides; Drug Metabolic Detoxication; Electrons; Engineering; Enzymes; FDA approved; Ferritin; Generations; Genetic; Genetic Engineering; Genetically Engineered Mouse; Glutamates; Goals; Grant; Human; Hypoxia; Immunotherapy; Intercellular Fluid; Interruption; Iron; KRAS2 gene; Knockout Mice; Learning; Lipids; MEK inhibition; MEKs; Malignant Epithelial Cell; Malignant Neoplasms; Malignant neoplasm of pancreas; Mammalian Cell; Mediating; Membrane; Membrane Lipids; Metabolism; Methods; Modeling; Molecular Biology; Mus; Mutant Strains Mice; Mutation; Necrosis; Normal Cell; Oncoproteins; Osmosis; Oxidation-Reduction; Oxidative Stress; Pancreatic Ductal Adenocarcinoma; Pathway interactions; Patients; Pharmaceutical Preparations; Phenocopy; Phenotype; Physiological; Polyunsaturated Fatty Acids; Process; Production; Property; Proteins; Reaction; Reactive Oxygen Species; Regimen; Resistance; Role; Rupture; Sampling; Science; Side; Source; Stable Isotope Labeling; Sulfhydryl Compounds; System; Systems Biology; TP53 gene; Techniques; Testing; Tissues; Tumor Immunity; United States; Water; Work; anti-cancer; antiporter; clinical translation; comparative efficacy; detoxication; dietary; extracellular; improved; in vivo; inhibitor; macromolecule; mortality; mouse model; mutant; novel; oxidative damage; pancreatic cancer cells; pancreatic ductal adenocarcinoma cell; pancreatic ductal adenocarcinoma model; pancreatic neoplasm; peroxidation; pharmacologic; preclinical efficacy; prevent; programs; recombinase; response; semi essential amino acid; targeted treatment; therapeutic target; therapeutically effective; translational approach; tumor; tumor metabolism; tumor microenvironment; uptake

Abstract: Pancreatic ductal adenocarcinoma (PDAC) is among the most lethal human malignancies and is responsible for over 48,000 deaths per year in the United States. PDAC tumors have several genetic and physiological properties that promote the generation of highly toxic reactive oxygen species (ROS), which can interact destructively with cellular macromolecules. As a result, these tumors rely heavily on ROS detoxification programs which employ thiol groups to mitigate the electron imbalances that define ROS. Those thiols are ultimately derived from cysteine, a semi-essential amino acid with a thiol-containing side chain. As cysteine is ultimately sourced from dietary sources, the import of exogenous cysteine is a critical step in the ROS detoxification process. In the first term of this grant, we tested the hypothesis that PDAC depends on cysteine import for survival. We found that depletion of cysteine, either through depletion from the media or by inhibition of cysteine uptake, resulted in the induction of ferroptosis, a form of regulated necrosis that occurs due to oxidative damage to cellular membranes. We demonstrated that cysteine depletion could selectively induce ferroptosis in PDAC tumors in vivo using both genetic and pharmacological approaches and we expanded the mechanistic understanding of ferroptosis by demonstrating that depletion of coenzyme A (a cysteine derivative) is necessary for the induction of ferroptosis in pancreatic tumor cells. Here we will extend these findings in order to potentiate the effects of cysteine depletion in PDAC. First, we will study the mechanistic difference between inhibition of system xC– versus degradation of exogenous cystine with the engineered enzyme cyst(e)inase. We will then directly compare the preclinical efficacy of these approaches in a genetically engineered models of PDAC, making use of a new, highly potent system xC– inhibitor. Second, we will pursue our earlier findings on the role of coenzyme A in regulating ferroptosis by studying whether high levels of coenzyme A in the tumor microenvironment might help suppress ferroptosis in malignant epithelial cells. This leads to a strategy of targeting ENPP proteins, which are necessary for the (indirect) import of exogenous coenzyme A. Third, we will determine whether the release of free iron from ferritin through via autophagy can promote ferroptosis in the context of cysteine depletion. This leads to a strategy of activating autophagy via MEK inhibition to increase lipid ROS production and sensitize to ferroptosis in combination with cysteine depletion. For each of these topics, we will pursue both basic science mechanisms and translational strategies. The studies will make use of genetically engineered mouse models of PDAC as well as novel tumor explant models developed by our group in which human or murine PDAC samples are cultured intact in an engineered system for up to a week. Together, these studies will further elucidate the mechanisms of response to cysteine-depletion strategies in pancreatic ductal adenocarcinoma.

摘要： 胰腺导管腺癌（PDAC）是最致命的人类恶性肿瘤之一， 在美国每年有超过48,000人死亡。PDAC肿瘤具有几种遗传和生理学特征， 促进产生高毒性活性氧（ROS）的特性， 破坏性地与细胞大分子结合。因此，这些肿瘤严重依赖于ROS解毒程序 其利用巯基来减轻限定ROS的电子不平衡。这些硫醇最终 衍生自半胱氨酸，一种具有含巯基侧链的半必需氨基酸。因为半胱氨酸最终 外源性半胱氨酸来源于膳食，是ROS解毒的关键步骤 过程在本基金的第一个学期，我们测试了PDAC依赖于半胱氨酸输入的假设， 生存我们发现，半胱氨酸的消耗，无论是通过从媒体消耗或通过抑制半胱氨酸 摄取，导致诱导铁凋亡，一种由于氧化损伤而发生的调节性坏死形式 到细胞膜。我们证明，半胱氨酸耗竭可以选择性地诱导PDAC中的铁凋亡 肿瘤在体内使用遗传和药理学方法，我们扩大了机制， 通过证明辅酶A（一种半胱氨酸衍生物）的消耗是必要的， 用于在胰腺肿瘤细胞中诱导铁凋亡。 在这里，我们将扩展这些研究结果，以加强半胱氨酸耗尽的影响，PDAC。一是 将研究系统xC-抑制与外源性胱氨酸降解之间的机制差异 与工程酶半胱氨酸（E）酶。然后，我们将直接比较这些药物的临床前疗效。 方法在基因工程模型的PDAC，利用一种新的，高效的系统xC-抑制剂。 第二，我们将通过研究辅酶A在调节铁凋亡中的作用来继续我们早期的发现。 肿瘤微环境中高水平的辅酶A是否有助于抑制恶性肿瘤患者的铁凋亡 上皮细胞这导致了靶向ENPP蛋白的策略，这是（间接）输入所必需的。 外源性辅酶A第三，我们将确定游离铁从铁蛋白中的释放是否通过经由 在半胱氨酸耗尽的情况下，自噬可促进铁凋亡。这导致了一种激活 通过MEK抑制的自噬增加脂质ROS产生并对铁凋亡敏感， 半胱氨酸耗竭对于每一个主题，我们都将追求基础科学机制和翻译 战略布局这些研究将利用PDAC的基因工程小鼠模型以及新的肿瘤 我们的研究小组开发的外植体模型，其中人或鼠PDAC样品在培养皿中完整培养。 工程系统长达一周。总之，这些研究将进一步阐明反应机制 胰腺导管腺癌的半胱氨酸耗竭策略。