Identifying Functional Drivers of MYC Activation via Developmental Enhancers in Diffuse Large B-cell Lymphoma

通过发育增强剂识别弥漫性大 B 细胞淋巴瘤中 MYC 激活的功能驱动因素

基本信息

批准号：
10207556
负责人：
RUSSELL James Hubbard RYAN
金额：
$ 35.34万
依托单位：
UNIVERSITY OF MICHIGAN AT ANN ARBOR
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-07-01 至 2025-06-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10207556
关键词：
8q24 Acetylation Affect Automobile Driving B-Cell Activation B-Cell Lymphomas B-Lymphocytes BCL6 gene Binding Biological Assay Biological Markers Biological Models Biology CRISPR interference Cell Line Characteristics Chromosomal Rearrangement Complex DNA Sequence Rearrangement DNA-Binding Proteins Data Development Diagnosis Disease Distal Distal Enhancer Elements Elements Enhancers Evaluation Event Future Gene Activation Gene Amplification Gene Expression Gene Expression Profiling Gene Mutation Genetic Genetic Enhancer Element Genetic Transcription Goals Growth Hyperactivity IGH@ gene cluster Immunity Immuno-Chemotherapy Immunoglobulin Gene Rearrangement Immunoglobulin Genes Immunoglobulins In Vitro Investigation Knowledge Lead Lymphoma Lymphoma cell MYC gene Mantle Cell Lymphoma Maps Mature B-Lymphocyte Mediating Modeling Mutation NF-kappa B Oncogene Activation Outcome POU2F2 gene Pathway interactions Patients Population Public Health Publishing Recurrence Recurrent disease Refractory Refractory Disease Regulation Reporter Repression Research Role Side Signal Transduction Structure of germinal center of lymph node Subgroup Therapeutic Transcriptional Activation Ursidae Family Work Xenograft procedure cancer type chemotherapy chromatin immunoprecipitation disorder risk factor C genomic locus high risk improved innovation large cell Diffuse non-Hodgkin&apos s lymphoma new therapeutic target notch protein novel novel therapeutic intervention overexpression predictive marker promoter transcription factor

项目摘要

PROJECT SUMMARY / ABSTRACT Overexpression of the oncogene MYC is characteristic of most high-risk diffuse large B-cell lymphomas, and is essential for the survival of lymphoma models. However, only half of DLBCLs assigned to high-risk subgroups of germinal center-like (GCB)-DLBCL by gene expression profiling bear activating genomic rearrangements of MYC, and MYC rearrangements are even less frequent in another common high-risk subtype, ABC-DLBCL. There is currently a poor understanding of the mechanisms that lead to MYC transcriptional dysregulation in DLBCL in the absence of an activating genomic rearrangement between MYC and an immunoglobulin gene locus (MYC-IG). The overall objective of this proposal is to define novel mechanisms of MYC regulation by distal enhancers. Our long-term goal is to use this understanding to develop improved therapeutic strategies and / or predictive biomarkers for DLBCL patients. Our working hypothesis is that transcriptional activation of MYC required to sustain DLBCL is dependent on the cis-regulatory activity of a small number of essential distal enhancer modules, located within much larger “super-enhancer” regions. These modules are located either within the 3’ region of the MYC locus on 8q24 (in DLBCL without MYC rearrangement), or in a genomic rearrangement partner locus such as 3q27, which is among the most common non-IG MYC rearrangement partners. We will utilize high-throughput CRISPR-interference profiling to perform robust functional interrogation of complex, multi-modular “super-enhancers” present in 8q24 and 3q27 in DLBCL cell lines that lack MYC rearrangements (Aim 1), or bear t(3;8)(q27;q24) rearrangements (Aim 2) respectively. Having identified the discrete distal enhancer elements that are required for MYC activation, we will utilize a complementary set of experimental approaches, including genetic deletion or mutation of enhancer sequences, chromatin immunoprecipitation, reporter assays, in vitro DNA-protein binding assays, and perturbation of trans factors and upstream pathways to characterize the regulation of these elements. Our preliminary data suggests that distinct enhancer modules within the 3’ MYC enhancer region are essential for DLBCLs with different aberrations affecting trans factors that selectively bind the essential enhancer modules. These aberrations include diverse signaling and genetic events that activate NF-kB factors, or alternately, hyperactivation of the coactivator OCA- B and a set of synergistically acting developmental transcription factors. We will evaluate the extent to which MYC activation in the context of a t(3;8) rearrangement is dependent on “hijacking” of MEF2B-regulated enhancer modules that are typically responsible for activation of the oncogene BCL6. Upon successful completion of the proposed research, we expect to rigorously define multiple distinct mechanisms by which enhancers and associated trans-factors can drive MYC transcriptional activation in DLBCL. Our innovative approach for identifying the key mechanisms underlying oncogene activation by complex multi-modular distal enhancers may serve as a model for similar investigations in a wide variety of cancer types.

项目摘要 /摘要癌基因MYC的过表达是大多数高风险弥漫性大B细胞淋巴瘤的特征，IS是但是，对于淋巴瘤模型的存活至关重要。通过基因表达分析熊激活基因组重排的生发中心样（GCB）-DLBCL MYC和MYC的重排在另一种常见的高风险亚型ABC-DLBCL中的频率更低。目前，人们对导致MYC转录失调的机制的理解很糟糕 DLBCL在MYC和免疫球蛋白基因之间没有激活的基因组重排的情况下基因座（myc-ig）。增强剂。我们的长期目标是用于制定改进的治疗策略和 /或 DLBCL患者的预测性生物标志物。维持DLBCL所需增强器模块，位于更大的“超级增强剂”区域。在8q24的MYC基因座的3'区域内（以MYC重排的DLBCL）或基因组中重排伙伴基因座，例如3Q27，这是最常见的非IG MYC重排之一合作伙伴。缺乏MYC 重排（AIM 1），或携带T（3; 8）（Q27; Q24）重排（AIM 2）尊重者。 MYC激活所需的离散远端增强子元素实验方法，包括遗传划分或增强子序列的突变，染色质免疫沉淀，报告基因测定，体外DNA-蛋白结合测定以及反式因子和扰动表征这些元素的上游途径。 3'MYC增强子区域内的增强器模块对于具有不同ABR的DLBCL至关重要有选择地结合基本增强子模块的反式因子。激活NF-KB因子的信号传导和遗传事件，或交替地激活OCA-的过度激活 B和一组协同作用的发育转录因素。在t（3; 8）重排的背景下，MYC激活取决于MEF2B期限的“劫持” 通常负责Oncogene Bcl6激活的增强器模块压缩了支撑研究，我们希望严格地定义了多种不同的机制增强剂和相关的跨因素可以在DLBCL中驱动MYC转录激活通过复杂的多模型远端来识别确定致癌基因激活的关键机制的方法增强剂可以作为各种癌症类型的类似研究的模型。