Role of microRNA-122 in hepatocarcinogenesis using conditional knock out mice

使用条件敲除小鼠研究 microRNA-122 在肝癌发生中的作用

基本信息

批准号：
8240491
负责人：
Kalpana Ghoshal
金额：
$ 31.33万
依托单位：
OHIO STATE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2010
资助国家：
美国
起止时间：
2010-05-17 至 2014-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8240491
关键词：
Adult Aflatoxin B1 Age Alcohols Animal Model Antineoplastic Agents Apoptosis Aromatic Amines Aromatic Polycyclic Hydrocarbons Biological Process Cancer Detection Cancer Etiology Cancer Patient Carcinogens Carcinoma Case Study Cell physiology Cells Cessation of life Chronic Cirrhosis Complex Data Death Rate Development Diabetes Mellitus Diagnostic Neoplasm Staging Diet Diethylnitrosamine Disease Disease Progression Down-Regulation Ectopic Expression Endothelial Cells Environmental Pollutants Epigenetic Process Etiology Excision Exposure to Fatty Liver Fibrosis Functional disorder Future Genes Goals Grant Growth Growth Factor Heavy Drinking Hemochromatosis Hepatic Hepatitis Hepatitis B Hepatitis B Virus Hepatitis C virus Hepatocarcinogenesis Hepatocyte Human IGF2 gene In Vitro Incidence Infection Infiltration Inflammation Inflammatory Injury Institutes Interleukin-6 Knock-out Knockout Mice Life Liposomes Liver Liver Dysfunction Liver diseases Liver neoplasms Magnetic Resonance Imaging Malignant Neoplasms Malignant neoplasm of liver MicroRNAs Mission Modeling Molecular Monitor Mus Mutation Neoplasm Metastasis Nitrosamines Nodule Nude Mice Obesity Oncogenic Operative Surgical Procedures Oral Contraceptives Patients Physiology Play Poison Predisposition Prevention Primary carcinoma of the liver cells Process Property Publishing RNA Radiation Recurrence Risk Factors Rodent Role Staging Testing Therapeutic Therapeutic Agents Tissues Treatment Efficacy Treatment Protocols Tumor Suppressor Proteins Tumor stage United States Vinyl Chloride Virus Work abstracting adenoma alpha-Fetoproteins base cancer cell cancer therapy chemical carcinogen chemotherapeutic agent chemotherapy choline deficient diet cytokine epithelial to mesenchymal transition feeding in vivo inhibitor/antagonist liver function liver transplantation loss of function men migration mimetics mortality mouse model nanoparticle non-alcoholic fatty liver nonalcoholic steatohepatitis novel outcome forecast preclinical study public health relevance response tumor tumor growth tumorigenic

项目摘要

DESCRIPTION (provided by applicant): The objective of this new R01 application is to advance our understanding of the role of miR-122 in hepatocarcinogenesis. HCC is the fifth most common cancer and the third common cause of cancer related death. The incidence of HCC is on the rise in USA, with little hope for cure or treatment through chemotherapy, radiation or other traditional cancer treatments. Its major risk factors are infection with hepatitis B and C viruses, and exposure to toxic chemicals, including alcohol, all of which cause chronic liver injury and inflammation. Using an animal model for hepatocarcinogenesis we were the first to demonstrate down regulation of miR-122, the most abundant liver-specific microRNA (~70% of the total miRNA) in the liver, during the initiation and progression of HCC and also in human primary HCCs. Suppression of miR-122 is a signature of HCCs with poor prognosis and metastasis. Studies with HCC cells in culture have shown that miR-122 functions as a tumor suppressor in vitro and in nude mice. To understand the biological functions of miR-122, especially in hepatocarcinogenesis, we have generated conditional knockout mice (supported by an R21 grant to the PI). These mice express 100 fold less miR-122 when crossed to AlbCre mice and spontaneously develop hepatitis in the liver with age, which is facilitated after feeding choline-deficient diet that promotes hepatocarcinogenesis. More importantly, miR-122 deleted (KO) mice are more susceptible to HCCs when exposed to diethylnitrosamine, a potent liver carcinogen. Based on these observations we hypothesize that miR-122 plays a critical role in maintaining liver function, and loss of miR-122 predisposes to liver disease including cancer. The specific aims of the proposal are: Aim 1. Investigate the role of miR-122 in a mouse model of nonalcoholic fatty liver disease (NAFLD) related HCC induced by feeding choline-deficient diet. 1a) The susceptibility of miR-122 / (KO) and miR-122fl/fl (control) mice to CDAA diet will be examined by comparing liver damage (apoptosis, steatosis or fatty liver, inflammation, fibrosis) and liver tumors (formation of adenomas and carcinomas) between these mice, and 1b) the involvement of miR-122 targets will be assessed. Aim 2. Investigate the role of miR-122 in diethylnitrosamine (DEN)-induced hepatocarcinogenesis. Pathological/molecular changes of mice injected with DEN will be monitored as described in Aim 1. Aim 3. Examine the therapeutic potential of miR-122 alone or in combination with chemotherapeutic agents to inhibit tumor growth in vivo in the DEN model. Mice will be injected weekly for 4 weeks with miR-122 mimetics loaded in galactosylated nanoparticles (to specifically target it to HCC cells) at early stages of tumor development (visualized by MRI) and the regression in the tumor growth will be compared to those in mice treated with the scrambled RNA nanoparticles. This study will elucidate the function of the most abundant liver-specific microRNA in maintaining normal liver physiology and also its therapeutic efficacy against hepatocellular carcinomas in an animal model. PUBLIC HEALTH RELEVANCE: Layman's Abstract The urgent need for new treatments for hepatocellular cancer (HCC) is warranted because incidence of HCC is increasing considerably in the United States, their dismal prognosis and the poor response of this cancer to treatment regimen currently available. This project focuses on the role of the loss of function of miR-122 in the development and progression of hepatocellular carcinoma (HCC), one of the most common human malignancies. Our previous studies have shown downregulation of miR-122 in HCCs of both human and rodent origin. Now we intend to show that the loss of function of this liver specific miR plays a causal role in the initiation and progression of HCC. If this is the case, these studies will open the way to the development of novel miR-122 therapy for this incurable disease. Thus, establishing role of miR-122 mimetic in an animal model (in preclinical trial) would be a major milestone in the treatment of this deadly disease in the near future.

描述（由申请人提供）：这项新的 R01 申请的目的是增进我们对 miR-122 在肝癌发生中作用的理解。 HCC 是第五大常见癌症，也是癌症相关死亡的第三大常见原因。在美国，肝癌的发病率呈上升趋势，通过化疗、放疗或其他传统癌症治疗方法治愈或治疗的希望渺茫。其主要危险因素是感染乙型和丙型肝炎病毒，以及接触有毒化学物质，包括酒精，所有这些都会导致慢性肝损伤和炎症。使用肝癌发生的动物模型，我们首次证明了 miR-122 在 HCC 的发生和进展过程中以及人类中的下调，miR-122 是肝脏中最丰富的肝脏特异性 microRNA（约占总 miRNA 的 70%）原发性肝癌。 miR-122 的抑制是预后不良和转移的 HCC 的标志。对培养中的 HCC 细胞的研究表明，miR-122 在体外和裸鼠体内发挥肿瘤抑制因子的作用。为了了解 miR-122 的生物学功能，特别是在肝癌发生中的生物学功能，我们培育了条件性基因敲除小鼠（由 PI 的 R21 资助支持）。当与 AlbCre 小鼠杂交时，这些小鼠的 miR-122 表达量减少了 100 倍，并且随着年龄的增长，肝脏中会自发出现肝炎，而在喂养缺乏胆碱的饮食后会促进肝癌的发生。更重要的是，miR-122缺失（KO）小鼠在接触二乙基亚硝胺（一种强效肝癌物质）时更容易患肝癌。基于这些观察结果，我们假设 miR-122 在维持肝功能中发挥着关键作用，而 miR-122 的缺失易导致包括癌症在内的肝病。该提案的具体目标是：目的 1. 研究 miR-122 在由缺乏胆碱饮食诱导的非酒精性脂肪性肝病 (NAFLD) 相关 HCC 小鼠模型中的作用。 1a) 通过比较肝损伤（细胞凋亡、脂肪变性或脂肪肝、炎症、纤维化）和肝肿瘤（形成将评估这些小鼠之间的腺瘤和癌）以及 1b）miR-122 靶标的参与情况。目标 2. 研究 miR-122 在二乙基亚硝胺 (DEN) 诱导的肝癌发生中的作用。将如目标 1 中所述监测注射 DEN 的小鼠的病理/分子变化。目标 3. 检查 miR-122 单独或与化疗药物组合在 DEN 模型中抑制体内肿瘤生长的治疗潜力。在肿瘤发展的早期阶段（通过 MRI 可视化），小鼠将每周注射半乳糖基化纳米颗粒中装载的 miR-122 模拟物（将其专门靶向 HCC 细胞），持续 4 周，并将肿瘤生长的回归与用乱序 RNA 纳米颗粒治疗的小鼠。这项研究将阐明最丰富的肝脏特异性 microRNA 在维持正常肝脏生理机能方面的功能及其在动物模型中对肝细胞癌的治疗功效。公众健康相关性：外行摘要迫切需要针对肝细胞癌 (HCC) 的新疗法，因为在美国，HCC 的发病率大幅增加，其预后不佳，而且这种癌症对目前可用的治疗方案反应不佳。该项目重点研究 miR-122 功能丧失在肝细胞癌 (HCC)（最常见的人类恶性肿瘤之一）的发生和进展中的作用。我们之前的研究表明 miR-122 在人类和啮齿类动物来源的 HCC 中下调。现在我们打算证明这种肝脏特异性 miR 功能的丧失在 HCC 的发生和进展中起着因果作用。如果是这样的话，这些研究将为开发针对这种不治之症的新型 miR-122 疗法开辟道路。因此，在动物模型中（临床前试验）建立 miR-122 模拟物的作用将是在不久的将来治疗这种致命疾病的一个重要里程碑。