Molecular Characterization of elF4B

eF4B 的分子表征

• 批准号: 10481155
• 负责人: Ronald B Gartenhaus
• 金额: --
• 依托单位: VA VETERANS ADMINISTRATION HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-10-01 至 2026-09-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10481155
• 关键词: 70-kDa Ribosomal Protein S6 Kinases; Accounting; Actins; Address; Aging; B-Cell Development; B-Lymphocytes; BCL2 gene; BCL6 gene; Biochemical; Bioenergetics; CD19 gene; Cell Compartmentation; Cell Line; Cell Maturation; Cell Ontogeny; Cell Separation; Cell model; Cells; Classification; Clinic; Clinical; Clinical Data; Clinical Research; Co-Immunoprecipitations; Cyclophosphamide; Cytomegalovirus; Data; Data Set; Dependence; Development; Diagnostic; Disease Resistance; Doxorubicin; Engineering; Enzymes; Essential Genes; Eukaryotic Initiation Factor-3; Eukaryotic Initiation Factor-4E; Eukaryotic Initiation Factors; Event; Fatty-acid synthase; Functional disorder; Gene Expression; Generations; Genes; Globin; Growth; Hand; High Fat Diet; Homeostasis; Human; Hybrids; Hyperactivity; Impairment; Incidence; Individual; Insulin; Knock-out; Laboratories; Ligase; LoxP-flanked allele; Luciferases; Lymphoma; Lymphoma cell; Lymphomagenesis; Malignant Neoplasms; Malignant lymphoid neoplasm; Mediating; Medical; Metabolic; Modification; Molecular; Molecular Target; Multi-Drug Resistance; Mus; Newly Diagnosed; Non-Hodgkin' s Lymphoma; Nutrient; Oncogenes; Oncogenic; Output; PIK3CG gene; Parkinson Disease; Partner in relationship; Pathway interactions; Patients; Peptide Hydrolases; Phenocopy; Phosphorylation; Phosphotransferases; Physiological; Polyubiquitination; Positioning Attribute; Prednisone; Progression-Free Survivals; Proliferating; Proteins; Publishing; Refractory; Relapse; Reporting; Research Personnel; Ribosomal Protein S6 Kinase; Role; STK11 gene; Seminal; Signal Transduction; Stress; Structure of germinal center of lymph node; Survival Rate; Therapeutic; Therapeutic Intervention; Tissues; Toxic effect; Transgenic Mice; Transgenic Organisms; Translations; Tumor Suppressor Proteins; Ubiquitin; Ubiquitination; United States; Validation; Veterans; Vincristine; Work; activated B cell like; c-myc Genes; clinical efficacy; clinically relevant; comorbidity; experimental study; fatty acid metabolism; genetic regulatory protein; genetic signature; improved; improved outcome; in vivo; insight; large cell Diffuse non-Hodgkin' s lymphoma; metabolome; mortality; mouse model; mutant; neoplastic cell; novel; obese patients; overexpression; pharmacologic; posttranscriptional; pre-clinical; preclinical study; promoter; rituximab; spatiotemporal; standard care; success; targeted agent; therapeutic candidate; therapeutic target; tool; tumor growth; ubiquitin isopeptidase; ubiquitin-protein ligase; ubiquitin-specific protease

Diffuse large B-cell lymphoma (DLBCL) represents the most common subtype of non-Hodgkin lymphoma (NHL), accounting for about 40% of all newly diagnosed cases in the United States. Despite the relative success of upfront R-CHOP therapy, the frequent occurrence of relapsed/refractory cases and the limitations to treating patients with co-morbidities has provided the impetus to discover novel actionable molecular targets to improve outcomes. Two of these rewired metabolic gene signatures of fatty acid synthase (FASN) & LKB1 (Liver Kinase B1) and the protein translational machinery components are emerging as putative candidates for therapeutic intervention in DLBCL. Supported by robust data from several independent laboratories, identification of unique molecular, metabolic signatures such as perturbation in fatty acid metabolism and depletion of LKB1 signaling are associated with DLBCL survival and underlying lymphomagenic mechanism(s). However, limited success in the clinical and pre-clinical arena targeting FASN and LKB1 due to pharmacological limitations has motivated investigators to identify downstream effectors, providing alternative actionable candidates with applicability in suppressing heterogenous DLCBL tumor growth. To point, exciting preliminary data from our lab identified eIF4B (Eukaryotic initiation factor 4B), a critical translational machinery component, is activated by enhanced FASN activity. It is broadly accepted that unregulated FASN activity is strongly correlated with multi-drug resistance, a prominent feature observed in patients with R-CHOP resistant disease. Further, we reported that FASN (an essential enzyme in the altered metabolome of DLBCL) directly regulates PI3K/S6Kinase mediated USP11 (Ubiquitin Specific Protease 11) driven eIF4B activity, which enhances oncogene expression in DLBCL. Unfortunately, there are no available murine models to delineate their physiological roles in B-cell development and homeostasis. Another critical question raised from our earlier published work was interrogating the molecular partners associated with the eIF4B ubiquitination machinery. Preliminary findings revealed PARK2 as a potential E3 Ligase, polyubiquitinating eIF4B. Further expanding our observation of the rewired metabolic impact on eIF4B driven translation, we found that LKB1 phosphorylates eIF4B, hindering eIF4B- sensitive gene expression. To address these findings in-depth, we will pursue the following three specific aims: Specific Aim 1: Define the molecular role of PARK2 in polyubiquitination of eIF4B and DLBCL proliferation, Specific Aim 2: Determine the impact of LKB1 activity on eIF4B-dependent translation and Specific Aim 3: Determine the molecular dependence of eIF4B in B-cells. While we have acquired compelling cell-based data demonstrating the functional importance of eIF4B in DLBCL, we will expand our mechanistic understanding by characterizing the physiological inputs of eIF4B in B-cells using engineered mouse models as well as crossing them with other clinically relevant oncogenic drivers (Myc) to assess their contribution to the development and progression of lymphomas. We have synthesized complementary mouse models (knock- out and transgenic/overexpression) to establish prima facia in vivo evidence, which will establish the pathophysiological impact of eIF4B expression in B-cell lymphomagenesis. Further, using molecular, cellular, and in vivo tools, we aim to validate how our proposed putative E3 ligase, PARK2, and the energetics kinase, LKB1, impact eIF4B functionality. Interestingly, we noted a significant positive correlation between PARK2 and LKB1 expression in the DLBCL dataset. We anticipate that the proposed studies will shed light on the functional and molecular events of eIF4B-dependent and independent roles in the ontogeny and pathophysiology of B- cells. In addition, molecular studies related to PARK2 and LKB1 will significantly enhance our understanding of this crucial post-transcriptional/translational mechanism(s) regulating eIF4B-driven lymphomagenesis. Ultimately, the successful completion of these experiments will lead to the identification and validation of novel actionable molecular target(s) in DLBCL and related lymphoid malignancies.

弥漫性大 B 细胞淋巴瘤 (DLBCL) 是非霍奇金淋巴瘤 (NHL) 最常见的亚型， 约占美国所有新诊断病例的40%。尽管取得了相对成功 前期R-CHOP治疗、复发/难治性病例的频繁发生以及治疗的局限性 患有合并症的患者为发现新的可操作分子靶点以改善病情提供了动力 结果。其中两个重新连接的脂肪酸合酶 (FASN) 和 LKB1（肝激酶）代谢基因特征 B1) 和蛋白质翻译机制组件正在成为治疗的假定候选者 干预 DLBCL。由多个独立实验室的可靠数据支持，识别独特的 分子代谢特征，例如脂肪酸代谢的扰动和 LKB1 信号传导的耗竭 与 DLBCL 生存和潜在的淋巴瘤发生机制相关。然而，在这方面取得的成功有限 由于药理学限制，针对 FASN 和 LKB1 的临床和临床前领域激发了 研究人员确定下游效应器，提供可替代的可操作候选者 抑制异质 DLCBL 肿瘤生长。值得注意的是，我们实验室的初步数据令人兴奋，确定了 eIF4B （真核起始因子 4B）是一种关键的翻译机制成分，由增强的 FASN 激活 活动。人们普遍认为，不受监管的 FASN 活性与多药耐药性密切相关，这是一种 在 R-CHOP 耐药性疾病患者中观察到的显着特征。此外，我们报道了 FASN（ DLBCL 代谢组改变中的必需酶）直接调节 PI3K/S6 激酶介导的 USP11 （泛素特异性蛋白酶 11）驱动 eIF4B 活性，增强 DLBCL 中癌基因的表达。 不幸的是，没有可用的小鼠模型来描述它们在 B 细胞中的生理作用 发育和稳态。我们早期发表的作品中提出的另一个关键问题是质疑 与 eIF4B 泛素化机制相关的分子伙伴。初步调查结果揭晓 PARK2 作为潜在的 E3 连接酶，对 eIF4B 进行多泛素化。进一步扩大我们对重新接线的观察 代谢对 eIF4B 驱动翻译的影响，我们发现 LKB1 磷酸化 eIF4B，阻碍 eIF4B- 敏感基因表达。为了深入解决这些发现，我们将采取以下三个具体措施 目标：具体目标 1：定义 PARK2 在 eIF4B 和 DLBCL 多泛素化中的分子作用 增殖，具体目标 2：确定 LKB1 活性对 eIF4B 依赖性翻译和 具体目标 3：确定 B 细胞中 eIF4B 的分子依赖性。虽然我们已经获得了 令人信服的基于细胞的数据证明了 eIF4B 在 DLBCL 中的功能重要性，我们将扩大我们的研究范围 通过使用工程小鼠表征 B 细胞中 eIF4B 的生理输入来理解机制 模型以及将它们与其他临床相关的致癌驱动因素 (Myc) 交叉以评估其贡献 淋巴瘤的发生和进展。我们合成了互补的小鼠模型（敲除 出和转基因/过度表达）建立初步的体内证据，这将建立 eIF4B 表达对 B 细胞淋巴瘤发生的病理生理影响。此外，利用分子、细胞、 和体内工具，我们的目标是验证我们提出的假定 E3 连接酶、PARK2 和能量激酶如何 LKB1，影响 eIF4B 功能。有趣的是，我们注意到 PARK2 和 DLBCL 数据集中的 LKB1 表达。我们预计拟议的研究将阐明功能 以及 eIF4B 依赖和独立作用在 B-个体发育和病理生理学中的分子事件 细胞。此外，与 PARK2 和 LKB1 相关的分子研究将显着增强我们对 这一关键的转录后/翻译机制调节 eIF4B 驱动的淋巴瘤发生。 最终，这些实验的成功完成将导致新型药物的鉴定和验证。 DLBCL 和相关淋巴恶性肿瘤中可操作的分子靶点。