Pharmacological targeting of the Unfolded Protein Response as an antitumor strate

未折叠蛋白反应的药理学靶向作为抗肿瘤策略

基本信息

批准号：
8193047
负责人：
ALBERT KOONG
金额：
$ 33.03万
依托单位：
UNIVERSITY OF PENNSYLVANIA
依托单位国家：
美国
项目类别：
财政年份：
2009
资助国家：
美国
起止时间：
2009-07-17 至 2013-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8193047
关键词：
5&apos Untranslated Regions Animals Anoxia Attenuated Biological Assay Biological Models Bortezomib Cell Culture Techniques Cell Survival Cells Cellular Assay Cellular Stress Clinical Collaborations Cytotoxic agent Data Defect Development Effectiveness Embryo Endoplasmic Reticulum Environment Exhibits Genes Glucose Goals Growth Growth Factor Health Human Hypoxia In Vitro Institution Kinetics Label Luciferases Malignant Neoplasms Measures Metabolic stress Modality Modeling Molecular Molecular Chaperones Multiple Myeloma Mus Mutate Oncogenic Oxygen Pathway interactions Phenotype Phosphotransferases Physiological Physiology Play Preclinical Drug Evaluation Process Property Proteasome Inhibitor Proteins Publishing Reporter Resistance Role Screening procedure Solid Neoplasm Stress System Testing Therapeutic Time Toxic effect Transgenic Mice Transgenic Organisms Translations Transplantation Treatment Efficacy Tumor Burden Up-Regulation Work Xenograft procedure Zebrafish angiogenesis antitumor agent arm base cell transformation chemotherapeutic agent cytotoxic design efficacy testing endonuclease endoplasmic reticulum stress improved in vivo inhibitor/antagonist killings neoplastic cell novel novel strategies pre-clinical programs research study response small molecule small molecule libraries tumor tumor growth tumor progression tumor xenograft tumorigenesis

项目摘要

DESCRIPTION (provided by applicant): Hypoxia/anoxia is a well-characterized component of the microenvironment of most solid tumor. Considerable experimental and clinical evidence supports the notion that hypoxia fundamentally alters the physiology of the tumor towards a more aggressive phenotype. The Unfolded Protein Response (UPR) is a cellular stress adaptation pathway which promotes cell survival in the presence of Endoplasmic Reticulum (ER) stress, including physiological stress in the tumor microenvironment. The PERK/eIF2a/ATF4 pathway reduces the global rates of protein translation thereby alleviating metabolic stress under hypoxia while at the same time induces the translational upregulation of important chaperones and pro-survival genes. Another UPR component is the activation of the endonuclease/kinase IRE1 and its immediate effector XBP1, which activate a transcriptional program aimed at increasing the folding capacity of the ER. Recent in vitro and in vivo studies from the labs of the two co-PIs, have shown that transformed cells with ablated UPR responses exhibit reduced tolerance to hypoxia in vitro and form tumors that are slower growing compared to tumors grown from cells with an intact UPR, indicating that UPR activation contributes to tumorigenesis. In preliminary studies, we have developed cell-based and animal-based assays for UPR activation and its inhibition by small molecules. The overall goal of this proposal is to validate UPR activation as an important anti- tumor target and to use novel in vitro and in vivo assays to identify potent inhibitors of this response as novel chemotherapeutic agents. In Aim 1, we will employ in vitro reporter assays of PERK activity to identify specific inhibitors of the PERK/eIF21/ATF4 pathway and test the effect of combined administration of these inhibitors with inhibitors of the IRE-1 pathway (Irestatins) on tumor cell survival under normoxia and hypoxia. In Aim 2, we will investigate the potential synergy between inhibitors of the PERK and IRE1 pathways with the proteasome inhibitor Bortezomib in killing hypoxic tumor cells in vitro and in vivo. Studies under Aim 3, will evaluate the use of Zebrafish as a model system to analyze the ability of inhibitors of the PERK and IRE1 pathways to inhibit xenotransplanted human tumors and to inhibit angiogenesis without causing significant developmental abnormalities. Finally, in Aim 4 we will test the efficacy and potential toxicity of identified compounds in mouse tumor models. We expect that these efforts will culminate in the development of specific and potent inhibitors of the UPR which alone, or in combination with existing antitumor agents and modalities will be effective in reducing tumor burden in preclinical and clinical malignancies. PUBLIC HEALTH RELEVANCE: A hallmark of solid tumors is the requirement to adapt to, and eventually overcome the stressful environment of low oxygen, growth factors, glucose and pH in the growing tumor mass. The requirement for neoangiogenesis to support tumor growth is now well established and is the basis for several promising anti-tumor modalities. Based on published data from our labs and others, we propose that the Unfolded Protein Response also plays a crucial role in adaptation to hypoxic stress, and like angiogenesis, represents an "encompassing and stable aspect of tumor development" and thus provides a unique opportunity for therapeutic exploitation. This proposal aims to identify agents that target key components of this adaptive response has the potential to offer additional and novel approaches to target the very stresses that hinder existing anti-tumor treatments and thereby improve antitumor treatment efficacy.

描述（由申请人提供）：缺氧/缺氧是大多数实体瘤微环境的一个明确特征的组成部分。大量的实验和临床证据支持这样的观点：缺氧从根本上改变肿瘤的生理学，使其变得更具侵袭性的表型。未折叠蛋白反应（UPR）是一种细胞应激适应途径，在内质网（ER）应激（包括肿瘤微环境中的生理应激）存在的情况下促进细胞存活。 PERK/eIF2a/ATF4 通路降低了蛋白质翻译的总体速率，从而减轻了缺氧下的代谢应激，同时诱导重要伴侣和促生存基因的翻译上调。另一个 UPR 成分是内切核酸酶/激酶 IRE1 及其直接效应子 XBP1 的激活，它激活旨在增加 ER 折叠能力的转录程序。两位共同PI的实验室最近进行的体外和体内研究表明，与具有完整UPR的细胞生长的肿瘤相比，具有被消除的UPR反应的转化细胞在体外表现出对缺氧的耐受性降低，并且形成的肿瘤生长速度较慢，表明 UPR 激活有助于肿瘤发生。在初步研究中，我们开发了基于细胞和动物的 UPR 激活及其小分子抑制检测方法。该提案的总体目标是验证 UPR 激活作为重要的抗肿瘤靶点，并使用新型体外和体内测定来鉴定该反应的有效抑制剂作为新型化疗药物。在目标 1 中，我们将采用 PERK 活性的体外报告基因检测来鉴定 PERK/eIF21/ATF4 通路的特异性抑制剂，并测试这些抑制剂与 IRE-1 通路抑制剂（Irestatins）联合给药对肿瘤细胞的影响常氧和缺氧条件下的存活率。在目标 2 中，我们将研究 PERK 和 IRE1 通路抑制剂与蛋白酶体抑制剂硼替佐米在体外和体内杀死缺氧肿瘤细胞方面的潜在协同作用。目标 3 下的研究将评估使用斑马鱼作为模型系统来分析 PERK 和 IRE1 通路抑制剂抑制异种移植人类肿瘤和抑制血管生成而不引起显着发育异常的能力。最后，在目标 4 中，我们将测试已鉴定化合物在小鼠肿瘤模型中的功效和潜在毒性。我们期望这些努力最终将开发出特异性且有效的 UPR 抑制剂，该抑制剂单独使用或与现有的抗肿瘤药物和方式联合使用将有效减少临床前和临床恶性肿瘤的肿瘤负荷。公共健康相关性：实体瘤的一个标志是需要适应并最终克服肿瘤生长中低氧、生长因子、葡萄糖和 pH 的压力环境。新血管生成支持肿瘤生长的要求现已得到充分确立，并且是几种有前途的抗肿瘤方式的基础。根据我们实验室和其他实验室发表的数据，我们提出，未折叠蛋白反应在适应缺氧应激方面也发挥着至关重要的作用，并且像血管生成一样，代表着“肿瘤发展的包容性和稳定方面”，从而为治疗性剥削。该提案旨在确定针对这种适应性反应关键成分的药物，有可能提供额外的新颖方法来针对阻碍现有抗肿瘤治疗的压力，从而提高抗肿瘤治疗效果。