Murine Model of HCV-Associated Human Liver Cancer

HCV 相关人类肝癌的小鼠模型

• 批准号: 8625280
• 负责人: Stanley M. Lemon
• 金额: $ 45.66万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-05-01 至 2017-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8625280
• 关键词: Adopted; Advanced Development; Animal Model; Binding; CD34 gene; Carcinogenesis Mechanism; Cell Culture Techniques; Cells; Chimerism; Chronic Hepatitis C; Complementary DNA; Complex; Country; Coupled; Coupling; Defective Viruses; Development; Dominant-Negative Mutation; Environment; Evaluation; Frequencies; Genes; Genotype; Goals; Hematopoietic stem cells; Hepatic; Hepatitis C; Hepatitis C virus; Hepatocarcinogenesis; Hepatocyte; Human; Human Development; Immune; Immune response; Immune system; Immunocompetent; Incidence; Infection; Inflammation; Lead; Lentivirus Vector; Liver; Liver Fibrosis; Malignant - descriptor; Malignant Neoplasms; Malignant neoplasm of liver; Mediating; Modeling; Molecular; Molecular Genetics; Morbidity - disease rate; Mus; Outcome; Oxidative Stress; Pathogenicity; Patients; Play; Primary carcinoma of the liver cells; Protocols documentation; Publishing; Recombinant DNA; Recombinants; Retinoblastoma; Retinoblastoma Protein; Risk; Role; SV40 T Antigens; Stem cells; Subfamily lentivirinae; Support System; System; T cell response; TACSTD2 gene; Testing; Therapeutic; Transgenes; Transplantation; Tumor Suppressor Proteins; Viral; Viral Pathogenesis; Virus; Virus Replication; Work; c-Myc Staining Method; carcinogenesis; fetal; follow-up; hepatitis C virus nucleocapsid protein; liver inflammation; mortality; mouse model; mutant; novel; oxidative DNA damage; response; sphingosine kinase; tumorigenesis; viral carcinogenesis; virus genetics; virus pathogenesis

DESCRIPTION (provided by applicant): Chronic hepatitis C virus (HCV) infection is now the leading cause of hepatocellular carcinoma (HCC), a highly lethal cancer with rapidly increasing incidence in the U.S. How HCV causes liver cancer is not well understood because of the lack of a small animal model for HCV pathogenesis. The overarching goal of this interdisciplinary, multi-PI project is to refine a recently developed humanized mouse model of hepatitis C (the AFC8-hu mouse) that possesses both a chimeric human liver and a functioning human immune system, and to use this model to elucidate viral mechanisms of carcinogenesis responsible for HCV-associated HCC. AFC8- hu mice engrafted with CD34+ human hematopoietic stem cells and EpCAM+ human hepatoblasts and hepatic stem cells achieve ~18% hepatic chimerism, are permissive for HCV infection, and develop a human HCV- specific T cell response with hepatic inflammation when infected with HCV. Remarkably, HCV infection of these mice results in significant hepatic fibrosis and evidence of oxidative DNA damage - hallmarks of chronic hepatitis C in human patients. Three interrelated specific aims are proposed to refine this model and to apply it to the study of the mechanisms of carcinogenesis responsible for HCV-associated HCC. Aim 1 focuses on optimizing protocols to enhance hepatic chimerism in AFC8-hu mice, and to infect AFC8-hu mice with genotype 1a HCVcc produced in cell culture from recombinant DNA, thereby providing a system supporting reverse molecular viral genetics studies of HCV-mediated carcinogenesis. In Aim 2, p53 will be inactivated in human hepatoblasts prior to transplantation into AFC8 mice to provide for accelerated development of human liver cancer in HCV-infected mice, and to facilitate discovery of novel determinants of HCV-mediated hepatocarcinogenesis. Aim 3 will utilize a reverse molecular genetics strategy to test the hypothesis that the disruption of critical tumor suppressor function by HCV promotes cancer in the genotoxic environment of immune-mediated hepatic inflammation and oxidative stress, and to specifically assess the role played by the targeted destruction of the retinoblastoma protein by HCV and sequestration of the tumor suppressor DDX3 by HCV core protein. Further development of the AFC8-hu mouse model, coupled with the use of infectious genotype 1a H77S virus produced from recombinant cDNA, will provide a robust and completely unique experimental system in which the complex interplay of direct and indirect mechanisms of carcinogenesis can be elucidated. The results of these studies will add significantly to current understanding of how HCV infection leads to the development of HCC, and advance the development and evaluation of new preventative and therapeutic strategies to lessen the considerable burden of morbidity and mortality imposed by liver cancer in patients with chronic hepatitis C.

描述（由申请人提供）：慢性丙型肝炎病毒（HCV）感染目前是肝细胞癌（HCC）的主要原因，肝细胞癌是一种高度致命的癌症，在美国发病率迅速增加。由于缺乏HCV发病机制的小动物模型，HCV如何导致肝癌尚不清楚。这个跨学科、多 PI 项目的总体目标是完善最近开发的丙型肝炎人源化小鼠模型（AFC8-hu 小鼠），该模型同时拥有嵌合的人类肝脏和功能正常的人类免疫系统，并利用该模型来阐明导致 HCV 相关 HCC 的病毒致癌机制。移植了 CD34+ 人类造血干细胞和 EpCAM+ 人类成肝细胞和肝干细胞的 AFC8-hu 小鼠达到约 18% 的肝脏嵌合状态，允许 HCV 感染，并在感染 HCV 时产生人类 HCV 特异性 T 细胞反应和肝脏炎症。值得注意的是，这些小鼠的 HCV 感染导致显着的肝纤维化和氧化 DNA 损伤的证据 - 这是人类患者慢性丙型肝炎的标志。提出了三个相互关联的具体目标来完善该模型并将其应用于 HCV 相关 HCC 致癌机制的研究。目标 1 重点是优化方案以增强 AFC8-hu 小鼠的肝嵌合性，并用重组 DNA 细胞培养物中产生的基因型 1a HCVcc 感染 AFC8-hu 小鼠，从而提供支持 HCV 介导的致癌作用的反向分子病毒遗传学研究的系统。在目标 2 中，在移植到 AFC8 小鼠体内之前，人类成肝细胞中的 p53 将被灭活，以加速 HCV 感染小鼠中人类肝癌的发展，并促进发现 HCV 介导的肝癌发生的新决定因素。目标3将利用反向分子遗传学策略来检验HCV对关键肿瘤抑制功能的破坏会在免疫介导的肝脏炎症和氧化应激的基因毒性环境中促进癌症的假设，并具体评估HCV对视网膜母细胞瘤蛋白的靶向破坏和HCV核心蛋白对肿瘤抑制因子DDX3的隔离所发挥的作用。 AFC8-hu小鼠模型的进一步开发，加上使用重组cDNA产生的传染性基因型1a H77S病毒，将提供一个强大且完全独特的实验系统，在该系统中可以阐明直接和间接致癌机制的复杂相互作用。这些研究的结果将显着增进目前对丙型肝炎病毒感染如何导致肝细胞癌发展的理解，并促进新的预防和治疗策略的开发和评估，以减轻肝癌对慢性丙型肝炎患者造成的巨大发病率和死亡率负担。