Project 5 - EBV Drivers of Oncogenesis and Novel Therapies

项目 5 - 肿瘤发生的 EBV 驱动因素和新疗法

• 批准号: 10910339
• 负责人: Shannon Celeste Kenney
• 金额: $ 7.24万
• 依托单位: UNIVERSITY OF WISCONSIN-MADISON
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-01 至 2024-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10910339
• 关键词: Affect; Attenuated; B-Lymphocytes; BCL2L11 gene; Bioinformatics; Burkitt Lymphoma; CDK4 gene; Cell Proliferation; Collaborations; Complex; Development; EZH2 gene; Epigenetic Process; Epstein-Barr Virus Infections; Epstein-Barr Virus latency; Generations; Genes; Genome; Growth; Helper-Inducer T-Lymphocyte; Hodgkin Disease; Human; Human Genetics; Human Herpesvirus 4; Immune response; Immunohistochemistry; Impairment; In Vitro; LMP1; Latent virus infection phase; Lymphocyte; Lymphoma; Lymphomagenesis; Lytic; Mediating; Methylation; MicroRNAs; Modeling; Molecular Biology; Molecular Genetics; Mutation; Oncogenes; Oncogenic Viruses; Pathway interactions; Pharmaceutical Preparations; Phenotype; Play; Proteins; RNA; Role; Supporting Cell; T-Lymphocyte; TNFSF5 gene; Therapeutic; Tumor Suppressor Proteins; Umbilical Cord Blood; Viral; Viral Antigens; Viral Pathogenesis; Virus; Virus Latency; Xenograft Model; humanized mouse; immunogenicity; in vivo; inhibitor; insight; large cell Diffuse non-Hodgkin' s lymphoma; lymphoblastoid cell line; mouse model; mutant; novel therapeutic intervention; novel therapeutics; promoter; transcription factor; transforming virus; tumor; tumorigenesis

PROJECT 5 – PROJECT SUMMARY/ABSTRACT Epstein-Barr virus (EBV) latent infection of B lymphocytes in vitro results in their growth transformation; however, in vivo, the growth of EBV-infected lymphocytes is normally constrained by robust immune responses against viral antigens. As a result, EBV genes essential for growth in vitro (such as LMP1 and EBNA2) are often not expressed in EBV-positive lymphomas such as Burkitt lymphoma (BL), Hodgkin Disease and diffuse large B cell lymphomas. Thus, in vitro transformation studies cannot adequately model how EBV infection promotes common types of EBV-positive human lymphomas that have more stringent forms of viral latency. The EBV BARTs microRNAs, and EBNA3A, are amongst the very few EBV-encoded genes/microRNAs expressed in human BLs, and are likely to play important “driver” roles in this type of lymphoma. We have shown that BARTs play an important role in maintaining the viability of EBV-positive BLs in vitro, and in decreasing the immunogenicity of EBV-transformed lymphoblastoid cell lines. The latent EBNA3A protein encodes a transcription factor that is essential for in vitro growth of EBV-transformed B cells, and is thought to collaborate with the closely related EBNA3C protein to inhibit expression of important tumor suppressors (including p16, p15 and BIM) by inducing EZH2-mediated H3K27 trimethylation of their promoters. However, the roles of BARTs and EBNA3A in promoting EBV-induced lymphomas in vivo have not been well studied, particularly in the context of lymphomas with more stringent latency. EBV-infected humanized mice provide sophisticated models for understanding the complex interactions between EBV, T cells, cellular pathway alterations and the microenvironment. We have recently developed a new cord blood- humanized mouse model that allows EBV mutants that are non-transforming in vitro (including EBNA2- deleted EBV) to form lymphomas with stringent viral latency in vivo. We propose to use two different humanized mouse models to examine the roles of BARTs and EBNA3A for EBV-induced lymphomas in vivo, and to determine if drugs which block essential EBNA3A functions inhibit lymphoma development. In Aim 1, we will examine how loss of BARTs affects viral pathogenesis in the context of type III versus Wp-restricted viral latency, and examine potential mechanisms by which BARTs expression is upregulated in vivo. In Aim 2, we will use the cord blood-humanized mouse model to explore the role of the EBNA3A protein in vivo. In Aim 3, we will explore the therapeutic potential of drugs (CK4/6 and EZH2 inhibitors) that block essential EBNA3A/3C-regulated pathways. This project interacts extensively with Projects 3 and 4, and uses the cores for immunohistochemistry, bioinformatics, and generation of EBV mutant genomes. The results of these studies should provide key insights into the mechanism(s) by which stringent EBV infection causes lymphomas in vivo, and may identify new therapeutic approaches for treating EBV-induced lymphomas.

项目5 -项目概要/摘要 EB病毒（EBV）在体外潜伏感染B淋巴细胞，导致其生长转化; 然而，在体内，EBV感染的淋巴细胞的生长通常受到强免疫抑制， 针对病毒抗原的反应。因此，体外生长所必需的EBV基因（如LMP 1和LMP 2）被发现是一种新的基因。 EBNA 2）通常在EBV阳性淋巴瘤如伯基特淋巴瘤（BL）、霍奇金淋巴瘤（Hodgkin淋巴瘤）中不表达。 疾病和弥漫性大B细胞淋巴瘤。因此，体外转化研究不能充分模拟 EBV感染如何促进常见类型的EBV阳性人类淋巴瘤， 病毒潜伏期的形式。EBV BARTs microRNA和EBNA 3A是极少数EBV编码的微RNA之一。 在人类BL中表达的基因/microRNA，并且可能在这种类型的基因表达中发挥重要的“驱动”作用。 淋巴瘤我们已经表明，BART在维持EBV阳性细胞的生存能力方面发挥着重要作用。 在体外的BL，并在降低EBV转化的淋巴母细胞系的免疫原性。潜 EBNA 3A蛋白编码EBV转化的B细胞体外生长所必需的转录因子， 并被认为与密切相关的EBNA 3C蛋白协同抑制重要肿瘤的表达， 通过诱导EZH 2介导的H3 K27三甲基化， 发起人。然而，BARTs和EBNA 3A在体内促进EBV诱导的淋巴瘤中的作用已被证实。 还没有得到很好的研究，特别是在淋巴瘤的情况下，更严格的潜伏期。ebv感染 人源化小鼠提供了复杂的模型，用于理解EBV、T 细胞、细胞通路改变和微环境。我们最近开发了一种新的脐带血- 人源化小鼠模型，其允许体外非转化的EBV突变体（包括EBNA 2- 缺失的EBV）在体内形成具有严格病毒潜伏期的淋巴瘤。我们建议使用两种不同的 人源化小鼠模型以检查BART和EBNA 3A在体内对EBV诱导的淋巴瘤的作用， 并确定阻断必需EBNA 3A功能的药物是否抑制淋巴瘤的发展。在目标1中， 我们将在III型与WP限制性的背景下研究BART的缺失如何影响病毒的发病机制。 病毒潜伏期，并检查BARTs表达在体内上调的潜在机制。在Aim中 2、利用脐血人源化小鼠模型探讨EBNA 3A蛋白在体内的作用。在 目的3，我们将探索药物（CK 4/6和EZH 2抑制剂）的治疗潜力， EBNA 3A/3C调节通路。该项目与项目3和项目4进行了广泛的交互，并使用了 用于免疫组织化学、生物信息学和EBV突变基因组的产生。的结果予以 研究应该提供关键的见解，通过严格的EBV感染引起的机制， 在体内的淋巴瘤，并可能确定新的治疗方法，用于治疗EBV诱导的淋巴瘤。