Deciphering and targeting a non-genetic driver pathway in hepatocellular carcinoma

破译和靶向肝细胞癌的非遗传驱动途径

基本信息

批准号：
10350679
负责人：
Narendra Wajapeyee
金额：
$ 47.8万
依托单位：
UNIVERSITY OF ALABAMA AT BIRMINGHAM
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-02-12 至 2026-01-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10350679
关键词：
American American Cancer Society BCL6 gene BTB/POZ Domain Biochemical Biological Assay Cell Culture Techniques Cell-Mediated Cytolysis Cessation of life Characteristics Cirrhosis Clinical Data Development Diagnosis Disease Distal Environment Erinaceidae Follow-Up Studies Genes Genetic Growth Hepatic Hepatocyte Human Immune system Immunocompetent Immunocompromised Host Immunosuppression Lead Liver Fibrosis Liver neoplasms Malignant Epithelial Cell Mediating Modeling Molecular Mus Names Neoplasm Metastasis Oncogenic Pathway interactions Patients Pharmaceutical Preparations Pharmacology Prevalence Primary carcinoma of the liver cells Probability Property Proteins RNA analysis Role Series Solubility Survival Rate T-Lymphocyte Testing Therapeutic Transcription Repressor Tumor Suppressor Genes Tumor Suppressor Proteins United States Validation Xenograft procedure analog base cell growth design effective therapy epigenetic silencing experimental study follow-up gene repression genetic corepressor genome-wide growth promoting activity humanized mouse improved inhibitor innovation knock-down liver cancer model mouse model mutant new therapeutic target non-genetic novel novel strategies novel therapeutics patient derived xenograft model pre-clinical rational design small hairpin RNA small molecule small molecule inhibitor subcutaneous transcriptome transcriptome sequencing tumor tumor growth tumor progression tumorigenesis zinc-binding protein

项目摘要

PROJECT SUMMARY Hepatocellular carcinoma (HCC) accounts for nearly 31,000 deaths annually in the United States alone. Factors that epigenetically silence an HCC tumor suppressor gene have the potential to promote tumorigenesis and thus may provide novel drug targets for HCC therapies. Using a genome-scale shRNA screen, we identified BCL6 as a putative and novel HCC driver gene. BCL6 is a transcriptional repressor with no previously documented role in HCC development and progression. We found that BCL6 was sufficient to transform cultured immortalized hepatocytes and promote HCC tumor growth in mouse subcutaneous xenografts. These oncogenic effects of BCL6 were dependent upon the ability of BCL6 to cause transcriptional repression because a transcriptional repression activity defective mutant of BCL6 failed to transform hepatocytes and promote tumor growth in mice. Based on our preliminary results, in this application we will establish the role of BCL6 as a driver of HCC, determine the mechanism by which BCL6 promotes tumor growth, and evaluate novel BCL6 targeting small-molecule inhibitors for HCC therapy. In Aim 1, we will establish the role of BCL6 in initiation and progression of hepatic tumorigenesis using a series of complementary mouse models that recapitulate characteristic features of HCC, including a mouse model of liver fibrosis (cirrhosis). This model recapitulates cirrhosis which is a cardinal feature of HCC. Additionally, based on our preliminary results that BCL6 inhibition in HCC cells increases their probability of getting cleared by T-cells, we will also use a mouse model with humanized immune system to study the impact of BCL6 in HCC progression in the context of a functional human immune system. In Aim 2, based upon the results of our RNA-seq and further follow up analysis, we will determine if epigenetic silencing of tumor suppressor HHIP and the zinc transporter ZIP14 by BCL6 is necessary for it to drive hepatic tumor growth. In Aim 3, we will evaluate our novel BCL6 inhibitors in pre-clinical mouse models of HCC, including HCC patient-derived xenograft (PDX) models for HCC therapeutics. In preliminary experiments, we have developed a novel small-molecule inhibitor designed to target the BTB domain of BCL6 and thereby disrupt its interaction with its co-repressors SMRT, NCOR and BCOR. We found that this novel BCL6 inhibitor L2-12019 inhibited the HCC cell growth in culture and in a human HCC xenograft-based mouse model. In Aim 3 studies, we will rationally design and evaluate new L2-12019 analogs to improve drug-like properties. The lead analog (with improved potency, selectivity, stability and solubility) will be tested with L2-12019 in pre-clinical mouse models of HCC and its efficacy will be compared with existing BCL6 inhibitors. Collectively, the results of the experiments proposed in this application will elucidate a novel non-genetic druggable pathway that promotes HCC tumor growth and progression and evaluate a new approach for treating HCC.

项目摘要仅在美国，肝细胞癌（HCC）每年就会造成近31,000人死亡。表观遗传上静态的因素抑制HCC肿瘤基因具有促进的潜力肿瘤发生，因此可能为HCC疗法提供新的药物靶标。使用基因组规模的shRNA 屏幕，我们将BCL6确定为推定的新型HCC驱动基因。 BCl6是一个转录阻遏物，先前没有记录在HCC开发和进展中的作用。我们发现Bcl6足以转化培养的永生化肝细胞并促进小鼠皮下HCC肿瘤的生长异种移植物。 Bcl6的这些致癌作用取决于Bcl6引起转录的能力抑制是因为转录抑制活性有缺陷的Bcl6突变体无法转化肝细胞并促进小鼠的肿瘤生长。根据我们的初步结果，在此应用程序中，我们将确定BCl6作为HCC驱动器的作用，确定Bcl6促进肿瘤的机制生长，并评估针对小分子抑制剂进行HCC治疗的新型BCL6。在AIM 1中，我们将使用一系列概括HCC特征特征的互补小鼠模型，包括鼠标模型肝纤维化（肝硬化）。该模型概括了肝硬化，这是HCC的基本特征。此外，根据我们的初步结果，HCC细胞中BCL6抑制会增加其清除的可能性通过T细胞，我们还将使用具有人源化免疫系统的小鼠模型来研究BCl6在 HCC在功能性人免疫系统的背景下进展。在AIM 2中，根据我们的结果 RNA-seq和进一步的后续分析，我们将确定肿瘤抑制剂的表观遗传沉默和 Bcl6的锌转运蛋白Zip14对于驱动肝肿瘤生长是必要的。在AIM 3中，我们将评估我们的新型BCL6抑制剂在旋转前小鼠HCC模型中，包括HCC患者衍生的异种移植物（PDX） HCC疗法的模型。在初步实验中，我们开发了一种新型的小分子抑制剂旨在针对BCL6的BTB域，从而破坏其与共抑制器SMRT的相互作用， ncor和bcor。我们发现这种新型的BCL6抑制剂L2-12019抑制了培养物中HCC细胞的生长以及基于人类HCC异种移植的小鼠模型。在AIM 3研究中，我们将合理设计和评估新的L2-12019类似物，以改善类似药物的特性。铅类似物（具有提高的效力，选择性，稳定性和溶解度）将在HCC前临床小鼠模型中使用L2-12019进行测试，其功效将是与现有的BCL6抑制剂相比。总的来说，本应用程序中提出的实验结果将阐明一种新型的非遗传可毒途径，该途径促进HCC肿瘤的生长和进展以及评估一种治疗HCC的新方法。