Targeting EGR1 signaling pathways in diffuse large B cell lymphoma

靶向弥漫性大 B 细胞淋巴瘤中的 EGR1 信号通路

基本信息

批准号：
10340232
负责人：
Lixin Rui
金额：
$ 34.96万
依托单位：
UNIVERSITY OF WISCONSIN-MADISON
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：
2021-12-20 至 2026-11-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10340232
关键词：
Affect Agammaglobulinaemia tyrosine kinase Animal Model B-Cell Activation B-Cell Antigen Receptor B-Lymphocytes Binding Proteins Bromodomain CRISPR/Cas technology Cancer Etiology Cell Death Cell Line Cells ChIP-seq Chromatin Clinical Data Drug Targeting Drug resistance EP300 gene Engineering Gene Expression Gene Expression Regulation Genes Genetic Genetic Transcription Genomics Growth Hematology Histones Human Immuno-Chemotherapy In Vitro Interferon Inducers Interferon Type I Interferons JAK1 gene Leukocytes Lymphocyte Lymphoma Lymphoma cell Malignant Neoplasms Mediating Molecular Multiple Myeloma Newly Diagnosed Oncogenes Oncogenic Pathway interactions Patients Pharmacology Proteins Reader Refractory Relapse Research Resistance Role Signal Pathway Signal Transduction Solid Stat3 Signaling Pathway Structure of germinal center of lymph node Testing Therapeutic Tonsil Transcriptional Activation Tumor Suppressor Proteins United States Up-Regulation Xenograft Model Xenograft procedure acquired drug resistance addiction antitumor effect base cancer cell cell growth clinical investigation design gene repression genetic manipulation genome wide association study in vivo inhibitor insight interest knock-down large cell Diffuse non-Hodgkin&apos s lymphoma lenalidomide leukemia lymph nodes molecular subtypes mortality mouse model neoplastic cell novel novel marker novel therapeutic intervention overexpression patient derived xenograft model preclinical study resistance mechanism response small hairpin RNA therapeutically effective transcriptome sequencing transcriptomics translational impact treatment strategy tumorigenesis

项目摘要

ABSTRACT Diffuse large B cell lymphoma (DLBCL), which represents 30% to 40% of newly diagnosed lymphomas, comprises two main molecular subtypes: activated B cell-like (ABC) and germinal center B cell-like (GCB). ABC DLBCL is more aggressive and less curable. More than 50% of patients with ABC DLBCL are refractory to or relapse from current frontline immunochemotherapy. Clinical use of ibrutinib, a selective inhibitor for Bruton tyrosine kinase (BTK) in the B cell receptor (BCR) signaling pathway, has achieved an initial response rate of 30%-40% in refractory/relapsed ABC DLBCL. Primary and acquired drug resistance, however, are still significant and impact the long-term survival of more than 60% of these patients. Therefore, understanding and targeting ibrutinib resistance mechanisms is an unmet clinical need. The BCR and JAK1/STAT3 signaling pathways are essential for the survival and proliferation of ABC DLBCL cells. We discovered that EGR1 is a converged downstream target of both pathways in ABC DLBCL and the level of EGR1 expression is elevated in ABC DLBCL compared with normal human tonsils and lymph nodes. We revealed novel mechanisms of EGR1 in transcriptional activation and repression of target genes with strong translational impact in treating aggressive lymphoma. EGR1 mediates transcriptional activation through the p300/H3K27ac/BRD4 axis to induce MYC expression and activate MYC target genes. Synergistic inhibition of cell growth was observed between EGR1 shRNA and AZD5153, a novel BRD4 inhibitor that is currently under clinical investigation. On the other hand, EGR1 mediates transcriptional repression of the type I interferon pathway genes, expression of which otherwise causes cancer cell death. Consistently, EGR1 knockdown by shRNA synergizes with the type I interferon inducer lenalidomide in growth inhibition of ABC DLBCL cells in vitro and in a xenograft mouse model. Using newly derived, ibrutinib-resistant ABC DLBCL cell lines, we demonstrated that EGR1 is among the most highly expressed genes relative to ibrutinib-sensitive parental cells, and co-targeting of BRD4 and interferon signaling inhibits growth of ibrutinib-resistant cells in vitro and in vivo. Based on these discoveries, the central hypothesis is that EGR1 is a unique oncogenic driver orchestrating multiple important signaling pathways and represents therapeutic vulnerability in patients with ABC DLBCL, especially for those with ibrutinib resistance. To test our hypothesis, we will pursue the following specific aims: (1) Elucidate effects of EGR1 on oncogenesis; (2) Establish the role of EGR1 in ibrutinib resistance; and (3) Co-target EGR1 downstream BRD4 and type I interferon signaling to overcome drug resistance in DLBCL. Dissecting the transcriptional activation and repression modules of EGR1 in DLBCL tumorigenesis and ibrutinib resistance is essential because the novel mechanistic insights will provide a molecular basis for developing the most effective therapeutic strategy for treatment of DLBCL patients, including those with ibrutinib resistance.

抽象的弥漫性大B细胞淋巴瘤（DLBCL），代表新诊断的淋巴瘤的30％至40％包括两个主要分子亚型：活化的B细胞样（ABC）和生发中心B细胞样（GCB）。 ABC DLBCL更具侵略性，更不可治愈。超过50％的ABC DLBCL患者对或当前一线免疫化学疗法复发。 ibrutinib的临床用途，布鲁顿的选择性抑制剂 B细胞受体（BCR）信号通路中的酪氨酸激酶（BTK）已达到初始反应率 30％-40％的难治性/复发性ABC DLBCL。但是，原发性和获得的耐药性仍然很重要并影响超过60％的患者的长期生存。因此，理解和定位 ibrutinib耐药机制是未满足的临床需求。 BCR和JAK1/STAT3信号通路是 ABC DLBCL细胞的存活和增殖至关重要。我们发现egr1是融合 ABC DLBCL中这两种途径的下游目标，并且在ABC DLBCL中升高EGR1表达水平与正常的人扁桃体和淋巴结相比。我们揭示了Egr1的新型机制靶基因的转录激活和抑制具有强烈翻译影响的目标基因治疗侵略性淋巴瘤。 EGR1通过P300/H3K27AC/BRD4轴介导转录激活以诱导MYC 表达并激活MYC靶基因。在EGR1之间观察到了对细胞生长的协同抑制作用 SHRNA和AZD5153是一种新型的BRD4抑制剂，目前正在临床研究中。另一方面， EGR1介导I型干扰素途径基因的转录抑制，否则表达导致癌细胞死亡。一致地，shRNA敲低的EGR1与I型干扰素诱导剂协同作用 Lenalidomide在体外和异种移植小鼠模型中对ABC DLBCL细胞的生长抑制作用。使用新的衍生的，耐二替尼的ABC DLBCL细胞系，我们证明了EGR1是最高的相对于依鲁替尼敏感的亲本细胞的表达基因，以及BRD4和干扰素信号的共同定位在体外和体内抑制耐二尼耐药细胞的生长。基于这些发现，中心假设是EGR1是一个独特的致癌驱动程序，协调了多个重要的信号通路，并且代表 ABC DLBCL患者的治疗脆弱性，尤其是对于患有依鲁鲁替尼耐药性的患者。测试我们的假设，我们将追求以下特定目的：（1）阐明Egr1对肿瘤发生的影响；（2）确定eGR1在ibrutinib抗性中的作用；（3）Co-Target EGR1下游BRD4和I型I 干扰素信号传导以克服DLBCL的耐药性。解剖转录激活和 DLBCL肿瘤发生和ibrutinib抗性中EGR1的抑制模块是必不可少的机械洞察力将为制定最有效的治疗策略提供分子基础治疗DLBCL患者，包括患有ibrutinib耐药性的患者。