B cell determinants of EBV latency

EBV 潜伏期的 B 细胞决定因素

• 批准号: 10701826
• 负责人: ETHEL CESARMAN
• 金额: $ 82.78万
• 依托单位: WEILL MEDICAL COLL OF CORNELL UNIV
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-09 至 2027-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10701826
• 关键词: 3-Dimensional; AIDS-Related Diffuse Large B-cell Lymphoma; AIDS-Related Lymphoma; Acquired Immunodeficiency Syndrome; Address; Affect; B cell differentiation; B lymphocyte immortalization; B-Cell Development; B-Cell Lymphomas; B-Lymphocytes; BCL6 gene; Biology; Burkitt Lymphoma; Cell Compartmentation; Cells; Cellular biology; Central Nervous System Lymphoma; ChIP-seq; Chromatin; Classification; Clustered Regularly Interspaced Short Palindromic Repeats; Cues; Cytometry; Cytosine; DNA; DNA Modification Methylases; DNMT3B gene; Development; Down-Regulation; Enzymes; Epigenetic Process; Epstein Barr Virus B cell lymphoma; Epstein-Barr Virus Infections; Epstein-Barr Virus latency; Epstein-Barr Virus-Related Lymphoma; Epstein-Barr Virus-Related Malignant Neoplasm; Event; Exhibits; Family; Foundations; Frequencies; Future; Gene Silencing; Genes; Genetic; Genetic Transcription; Genome; Grant; HIV; Herpesviridae; Heterogeneity; Histologic; Histone H1; Histones; Hodgkin Disease; Human; Human Herpesvirus 4; Image; Immune; Immunocompetent; Immunologics; Infection; Integration Host Factors; Intrinsic factor; Knowledge; LMP1; Large-Cell Immunoblastic Lymphoma; Lead; Learning; Link; Lymphoma; Lymphomagenesis; Lymphoproliferative Disorders; Maintenance; Malignant - descriptor; Malignant Neoplasms; Mediating; Memory; Methylation; Methyltransferase; Mexico; Modeling; Molecular; Mutate; Mutation; Mutation Analysis; Oncogenic; Oncogenic Viruses; Oncoproteins; PRC1 Protein; Patients; Pattern; Persons; Protein Isoforms; Proteomics; Recurrence; Regulation; Role; STAT3 gene; Sampling; Signal Transduction; Site; Structure of germinal center of lymph node; T-Cell Immunodeficiency; Tumor-Derived; Ubiquitination; Untranslated RNA; Variant; Viral; Viral Genome; Viral Proteins; Virus; Virus Latency; Work; antiretroviral therapy; cDNA Expression; cancer genome; chemical genetics; co-infection; cohort; cytokine; derepression; driver mutation; epigenome; genetic analysis; genetic manipulation; high risk; histone methyltransferase; infected B cell; interleukin-21; large cell Diffuse non-Hodgkin' s lymphoma; latent gene expression; loss of function mutation; lytic gene expression; multiple omics; neoplastic cell; novel therapeutic intervention; post-transplant; pressure; primary effusion lymphoma; programs; promoter; recruit; superinfection; tumor; viral DNA; viral genomics; virology

Epstein-Barr virus (EBV) is an oncogenic herpesvirus associated with multiple cancers, including Burkitt lymphoma, Hodgkin lymphoma, primary central nervous system lymphoma and post-transplant lymphomas. EBV-associated B-cell lymphomas occur at significantly higher frequency in the setting of HIV co-infection, even with the use of antiretroviral therapy. AIDS-related lymphomas (ARLs) are most commonly diffuse large B cell lymphomas (DLBCLs), followed by Burkitt lymphoma and classical Hodgkin lymphoma (cHL), all frequently associated with EBV infection. Each of these cancers is linked to a viral latency program that is used as EBV- infected B-cells navigate the B-cell compartment to colonize memory cells, the reservoir for lifelong infection. Yet, much remains to be learned about epigenetic mechanism that control viral oncoprotein expression, and how this can ultimately be exploited in novel therapeutic approaches. We therefore recently performed CRISPR and chemical genetic analysis to identify host factors that tightly regulate the expression of EBV oncoproteins in B-cells. These analyses highlighted host DNA and histone methyltransferases with key roles in regulation of EBV latency and lytic gene expression. Characterization of top screen hits revealed multiple layers of EBV oncoprotein control, yet, how DNA and histone methyltransferases target specific EBV genomic promoter sites remains largely unknown. In parallel, we integrated these studies with tumor genome mutation analysis to identify host genes that are mutated at high frequency in EBV-infected and EBV-uninfected B-cell lymphomas. These analyses recently identified that linker H1 histone genes, which are highly recurrent in B cell lymphomas, are genetic driver mutations in lymphomagenesis. They also demonstrated that histone H1 mutation drives malignant transformation via three-dimensional genome reorganization, resulting in epigenetic reprogramming and de-repression of developmentally silenced genes. Notably, our proteomic analysis identified that EBV strongly downmodulates expression of multiple linker histone 1 isoforms, though it remains unknown how this H1 subversion alters the viral and host genome landscape in EBV-associated lymphomas. We hypothesize that germinal center microenvironment cues orchestrate B-cell epigenetic programs that together with EBV oncoprotein effects on linker histone expression dictate tumor latency programs. While immunological selective pressures also contribute to latency, we propose that T-follicular helper signals and cell intrinsic factors control EBV latency patterns. Our specific aims are therefore to: 1) Identify how key germinal center cytokines affect epigenetic writers to alter the EBV epigenome and dictate latency program selection. 2) Identify dynamic histone H1 roles in EBV epigenome and latency program regulation. 3) Define the relationship between B-cell differentiation state, epigenetic profile, and EBV latency pattern in HIV+ DLBCL. Collectively, these studies address long-standing question in the EBV tumor virology field and lay the foundation for novel therapeutic approaches to EBV-driven human malignancies.

EB病毒（EBV）是一种致癌性疱疹病毒，与多种癌症有关，包括伯基特 淋巴瘤、霍奇金淋巴瘤、原发性中枢神经系统淋巴瘤和移植后淋巴瘤。 EBV相关的B细胞淋巴瘤在HIV合并感染的情况下发生的频率明显更高， 即使使用了抗逆转录病毒疗法。艾滋病相关淋巴瘤（ARL）最常见的是弥漫性大B淋巴瘤 细胞淋巴瘤（DLBCL），其次是伯基特淋巴瘤和经典霍奇金淋巴瘤（cHL），都经常 与EBV感染有关。这些癌症中的每一种都与病毒潜伏期程序有关，该程序被用作EBV- 受感染的B细胞在B细胞区室中移动，以定殖记忆细胞，记忆细胞是终身感染的储存库。 然而，关于控制病毒癌蛋白表达的表观遗传机制， 如何最终将其用于新的治疗方法。因此，我们最近进行了 CRISPR和化学遗传分析鉴定了严格调节EBV表达的宿主因子 B细胞中的癌蛋白。这些分析强调了宿主DNA和组蛋白甲基转移酶在以下方面的关键作用： 调节EBV潜伏期和裂解基因表达。顶部屏幕点击的特征显示多个 EBV癌蛋白控制层，然而，DNA和组蛋白甲基转移酶如何靶向特定的EBV基因组 启动子位点仍然是未知的。同时，我们将这些研究与肿瘤基因组突变相结合， 鉴定在EBV感染和未感染的B细胞中高频率突变的宿主基因的分析 淋巴瘤这些分析最近发现，在B中高度重复的接头H1组蛋白基因， 细胞淋巴瘤是淋巴瘤发生中的遗传驱动突变。他们还证明了组蛋白H1 突变通过三维基因组重组驱动恶性转化，导致表观遗传 重新编程和去抑制发育沉默基因。值得注意的是，我们的蛋白质组分析 发现EBV强烈下调多接头组蛋白1亚型的表达，尽管它仍然存在， 目前还不清楚这种H1颠覆如何改变EBV相关淋巴瘤中的病毒和宿主基因组景观。 我们假设，生发中心微环境线索编排B细胞表观遗传程序 与EBV癌蛋白对连接组蛋白表达的影响一起决定了肿瘤潜伏期 程序.虽然免疫选择性压力也有助于潜伏期，我们提出，T-滤泡 辅助信号和细胞内在因子控制EBV潜伏期模式。因此，我们的具体目标是：1） 确定关键的生发中心细胞因子如何影响表观遗传作者改变EBV表观基因组并决定 等待时间程序选择。2)确定动态组蛋白H1在EBV表观基因组和潜伏期程序中的作用 调控3)定义B细胞分化状态、表观遗传特征和EBV潜伏期之间的关系 HIV+ DLBCL的模式。总的来说，这些研究解决了EBV肿瘤病毒学中长期存在的问题， 该领域的研究为EBV驱动的人类恶性肿瘤的新型治疗方法奠定了基础。