Synergistic innate immune activation and cell killing by RIG-I ligands in HCV-HCC

HCV-HCC 中 RIG-I 配体的协同先天免疫激活和细胞杀伤

• 批准号: 8238622
• 负责人: Lee Gehrke
• 金额: $ 20.95万
• 依托单位: MASSACHUSETTS INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-03-12 至 2014-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8238622
• 关键词: 3' Untranslated Regions; Adjuvant; Affinity; Agonist; Antiviral Agents; Apoptosis; Apoptotic; Binding; Cell Culture System; Cell Death; Cell Death Signaling Process; Cells; Cirrhosis; Clinical; Coculture Techniques; Collaborations; Complex; Data; Defect; Defense Mechanisms; Deoxyuridine; Disease; Environment; Fostering; Genomics; Goals; Hepatitis B Virus; Hepatitis C; Hepatitis C virus; Hepatocyte; Human; Immune; Immune response; Immune system; Immunologic Adjuvants; Incidence; Inflammatory; Interferon Type I; Interferons; Laboratories; Length; Ligands; Light; Liver; Malignant Epithelial Cell; Malignant Neoplasms; Malignant neoplasm of liver; Maps; Mediating; Melanoma Cell; Membrane; Mitochondria; Modeling; Modification; Mus; NF-kappa B; Normal Cell; Nucleotides; Pathway interactions; Pattern recognition receptor; Physiological; Positioning Attribute; Prevention approach; Primary carcinoma of the liver cells; Proteins; RNA; RNA Binding; RNA-Binding Proteins; Reagent; Reporting; Ribose; Secondary to; Signal Pathway; Signal Transduction; Signal Transduction Pathway; Signaling Protein; System; TRADD gene; Testing; Therapeutic; Therapeutic Intervention; Toll-like receptors; United States; Vaccines; Viral; Virus Diseases; Work; arm; base; cancer cell; cell killing; cytokine; fighting; helicase; hepatoma cell; immune RNA; immune activation; innovation; killings; mitochondrial membrane; neoplastic cell; novel; novel strategies; prevent; receptor; research study; response; statistics; tool; tripolyphosphate; tumor; viral RNA

DESCRIPTION (provided by applicant): Hepatocellular carcinoma (HCC) is an unfortunate and predictable consequence of hepatitis C virus (HCV) infections, defining it as a significant global human heath problem. There is no vaccine against HCV, and current treatments fail to cure HCV infections in nearly half of the cases. The consequence is that the untreated infected cells continue on their course toward cirrhosis and HCC. The goal of this project is to test the promise of a synergistic double hit against HCC by using RNA molecules to activate both innate immune and cell death response pathways in liver. This goal is based on recent evidence demonstrating that these pathways share common proteins and jointly assemble at the mitochondrion. Prior work from our laboratory has identified RNAs derived from the 3' untranslated region of hepatitis C genomic RNA or its antisense sequence that are potent activators of the RIG-I mediated innate immune signaling pathway. These RNAs have a 5' triphosphate, are about 100 nucleotides in length, and are described as polyU/UC or polyAG/A. Unlike the membrane-bound toll-like receptors, RIG-I is a cytoplasmic RNA binding protein and pattern recognition receptor that recognizes RNAs with a 5' triphosphate, initiating a signaling cascade that culminates in the expression if Type I interferons, establishing an antiviral environment. To date, our work has focused primarily on understanding how RIG-I binds to viral RNA and how the signaling pathway is activated. We discovered that RNAs containing modified ribose groups (2'-F deoxyuridine, for example) bind to RIG-I, but do not activate signaling, in contrast to their unmodified counterparts. Recent evidence from our group shows that the modified RNAs are unique tools that can be used to dissect the steps in the signal transduction pathway to understand mechanisms and potentially identify points of therapeutic intervention. In this proposal, we extend our work to focus on determining if the RIG-I agonist RNAs (polyU/UC and polyAG/A) activate both innate immune signaling and cell death pathways. Part of the approach focuses on the innovative use of a novel primary human liver culture cell system that maintains many physiologic markers at normal levels for up to two weeks, permitting experimentation in a physiologically relevant model. The significance of our approach is that RIG-I agonist RNAs may serve as adjuvants to boost an innate immune response to limit HCV infection, while also stimulating cell death pathways to kill cells that are progressing toward tumor formation. Indeed, recent studies have shown that RIG-I agonists activate cell death signaling, and that melanoma cells are more susceptible than normal cells to the killing effects. Although toll-like receptor ligands of the innate immune system are being used a immunostimulants to treat clinical disease, related approaches that activate the RIG-I- like helicase receptors can now be considered. This proposal has the potential to foster new ideas about how both HCV infection and the liver cancer that often follows can be treated or prevented. PUBLIC HEALTH RELEVANCE: Hepatitis C virus infections continue to increase globally, and a protective vaccine is not available. An unfortunate consequence of many hepatitis C virus (HCV) infections is that the disease progresses to cirrhosis and liver cancer that have poor survival statistics. We have characterized RNA molecules that boost the immune response to fight virus infections, and the goal of this proposal is to determine if the same molecules will also activate a cell response that kills cancer cells. We propose that this synergistic attack mechanism has potential as a novel approach for treating viral infections that progress to cancers.

描述(由申请人提供)：肝细胞癌是丙型肝炎病毒感染的一种不幸的和可预见的后果，将其定义为一个重大的全球人类健康问题。目前还没有针对丙型肝炎病毒的疫苗，目前的治疗方法在近一半的病例中未能治愈丙型肝炎病毒感染。结果是，未经治疗的感染细胞继续向肝硬变和肝细胞癌发展。该项目的目标是通过使用RNA分子激活肝脏中的先天免疫和细胞死亡反应通路来测试协同双重打击抗肝癌的前景。这一目标是基于最近的证据表明，这些途径共享共同的蛋白质，并在线粒体上共同组装。我们实验室以前的工作已经发现，来自丙型肝炎基因组RNA 3‘非翻译区的RNA或其反义序列是RIG-I介导的天然免疫信号通路的有效激活因子。这些RNA有一个5‘三磷酸，全长约100个核苷酸，被描述为PolyU/UC或PolyAG/A。与膜结合的Toll样受体不同，RIG-I是一个细胞质RNA结合蛋白和模式识别受体，它识别带有5’三磷酸的RNA，启动一系列信号级联，最终导致I型干扰素的表达，建立一个抗病毒环境。到目前为止，我们的工作主要集中在了解RIG-I如何与病毒RNA结合以及信号通路如何被激活。我们发现，与未修饰的RNA相比，含有修饰核糖基的RNA(例如2‘-F脱氧尿苷)与RIG-I结合，但不激活信号转导。我们小组最近的证据表明，修饰的RNA是独特的工具，可以用来剖析信号转导途径中的步骤，以了解机制并潜在地识别治疗干预点。在这个提案中，我们将工作重点放在确定RIG-I激动剂RNAs(PolyU/UC和PolyAG/A)是否同时激活先天性免疫信号和细胞死亡途径。该方法的部分重点是创新地使用一种新型的原代人类肝脏培养细胞系统，该系统将许多生理标记物保持在正常水平长达两周，从而允许在生理相关的模型中进行实验。我们方法的意义在于，RIG-I激动剂RNA可以作为佐剂来增强先天免疫反应，以限制丙型肝炎病毒感染，同时也刺激细胞死亡途径，以杀死正在向肿瘤形成发展的细胞。事实上，最近的研究表明，RIG-I激动剂激活了细胞死亡信号，黑色素瘤细胞比正常细胞更容易受到杀伤作用的影响。尽管天然免疫系统的Toll样受体配体正被用作免疫刺激剂来治疗临床疾病，但现在可以考虑激活Rig-I样解旋酶受体的相关方法。这项提议有可能促进关于如何治疗或预防丙型肝炎病毒感染和随之而来的肝癌的新想法。 公共卫生相关性：全球丙型肝炎病毒感染继续增加，目前还没有保护性疫苗。许多丙型肝炎病毒(丙型肝炎病毒)感染的一个不幸的后果是，这种疾病进展为肝硬变和肝癌，而这些疾病的存活率统计很差。我们已经确定了增强免疫反应以对抗病毒感染的RNA分子的特征，这项提议的目标是确定同样的分子是否也会激活杀死癌细胞的细胞反应。我们认为，这种协同攻击机制有可能成为治疗进展为癌症的病毒感染的一种新方法。