The Use of Novel Peptide Probes to Study Proteasome Regulation by Src Family Kinases in Diffuse Large B-cell Lymphoma

使用新型肽探针研究弥漫性大 B 细胞淋巴瘤中 Src 家族激酶的蛋白酶体调节

• 批准号: 9113346
• 负责人: Marissa L Cann
• 金额: $ 3.13万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-09-01 至 2017-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9113346
• 关键词: Address; Affect; Antineoplastic Agents; Apoptotic; B-Lymphocytes; Caspase; Cell Line; Cell physiology; Cells; Chronic; Clinical Treatment; Clinical Trials; Complement; Dasatinib; Data; Dose; Drug resistance; Family; Gene Expression; Gene Expression Profiling; Goals; Lead; Link; Lymphoma; Malignant Neoplasms; Measures; Mediating; Non-Hodgkin' s Lymphoma; Pathway interactions; Patients; Peptides; Play; Post-Translational Protein Processing; Progression-Free Survivals; Proteasome Inhibitor; Protein Tyrosine Kinase; Proteins; Receptors, Antigen, B-Cell; Refractory; Regulation; Relapse; Role; Sampling; Signal Pathway; Signal Transduction; Small Interfering RNA; Structure of germinal center of lymph node; Therapeutic Agents; Trypsin; United States; Work; base; chemotherapeutic agent; chemotherapy; chymotrypsin; clinically relevant; inhibitor/antagonist; insight; kinase inhibitor; knock-down; large cell Diffuse non-Hodgkin' s lymphoma; member; multicatalytic endopeptidase complex; new technology; novel; outcome forecast; overexpression; peptide A; protein degradation; protein expression; public health relevance; receptor; response; sensor; signal processing; small molecule inhibitor; src-Family Kinases; standard care; targeted treatment; therapeutic target; tool; tumor progression

 DESCRIPTION (provided by applicant): Non-Hodgkin Lymphoma (NHL) is the seventh most common cancer in the United States, with diffuse large B-cell lymphoma (DLBCL) being the most common subtype. The standard treatment of DLBCL is a cocktail of chemotherapeutic agents called R-CHOP, but roughly 10% of DLBCL patients will be refractory to this therapy, and a substantial 40% of DLBCL patients who do respond to R-CHOP will relapse within 5 years. By gene expression profiling, patients with DLBCL can be categorized into two clinically relevant subtypes: activated B-cell (ABC) DLBCL and germinal center B-cell (GCB) DLBCL. Patients with ABC DLBCL have a much worse overall survival and progression-free survival in response to standard chemotherapy than patients with GCB DLBCL. Chronic, overactive signaling through the B-cell receptor (BCR) and the anti-apoptotic NF-B pathway are hallmarks of the ABC but not the GCB DLBCL subtype, and could therefore be particularly important for promoting tumor progression and drug resistance. The Src family kinases (SFKs) are a family of nonreceptor tyrosine kinases that are important for signaling through the BCR. The proteasome is crucial for facilitating the NF-B signaling pathway, as it degrades the negative regulators of NF-B signaling. Both proteasome inhibitors and inhibitors of SFK signaling targets have shown significant promise in clinical trials for the treatment of ABC DLBCL. While there is some evidence that the SFKs may play a role in regulation of the proteasome, the direct effects of SFK modulation on the proteasome are not well-studied. This proposal aims to study the role of the SFKs in the regulation of the proteasome through the use of novel peptide probes. A set of three distinct, sensitive peptide sensors have been developed to simultaneously measure the chymotrypsin-like, trypsin-like, and caspase-like activities of the proteasome. A peptide sensor has also been developed to measure the catalytic activity of the SFKs. Preliminary studies demonstrate a dose-dependent reduction in proteasome activity in response to the SFK inhibitor dasatinib. Thus, the hypothesis of this proposal is that the SFKs activate the proteasome. The SFKs will be inhibited in DLBCL cells through the use of small molecule inhibitors and siRNA-mediated knockdown, after which changes in proteasome activity, protein expression, gene expression, and protein post-translational modifications will be assessed. Subsequent studies will examine the same changes after activation of one or more of the SFK members through expression of constitutively active constructs. This work will provide valuable insight into the SFK-proteasome signaling axis in DLBCL, and will therefore provide a better understanding of the cellular processes that contribute to tumor progression and drug resistance in DLBCL. The findings of this study could lead to the identification of additional therapeutic targets for the treatment of relapsed and refractory DLBCL.

 描述（由申请人提供）：非霍奇金淋巴瘤（NHL）是美国第七大常见癌症，弥漫性大B细胞淋巴瘤（DLBCL）是最常见的亚型。DLBCL的标准治疗是称为R-CHOP的化学治疗剂的混合物，但大约10%的DLBCL患者对该疗法难治，并且对R-CHOP有反应的DLBCL患者中有40%将在5年内复发。通过基因表达谱分析，DLBCL患者可分为两种临床相关亚型：活化B细胞（ABC）DLBCL和生发中心B细胞（GCB）DLBCL。与GCB DLBCL患者相比，ABC DLBCL患者对标准化疗的总生存期和无进展生存期更差。通过B细胞受体（BCR）和抗凋亡NF-κ B B途径的慢性过度活跃的信号传导是ABC而不是GCB DLBCL亚型的标志，因此对于促进肿瘤进展和耐药性可能特别重要。Src家族激酶（SFK）是一个非受体酪氨酸激酶家族，对通过BCR进行信号传导很重要。蛋白酶体对于促进NF-κ B B信号传导途径是至关重要的，因为它降解NF-κ B B信号传导的负调节因子.蛋白酶体抑制剂和SFK信号传导靶点抑制剂在治疗ABC DLBCL的临床试验中显示出显著的前景。虽然有一些证据表明SFK可能在调节蛋白酶体中发挥作用，但SFK调节对蛋白酶体的直接影响尚未得到充分研究。本研究的目的是通过使用新型肽探针来研究SFKs在蛋白酶体调节中的作用。一组三个不同的，敏感的肽传感器已被开发，同时测量糜蛋白酶样，胰蛋白酶样，半胱天冬酶样活性的蛋白酶体。还开发了肽传感器来测量SFK的催化活性。初步研究表明，蛋白酶体活性对SFK抑制剂达沙替尼的反应呈剂量依赖性降低。因此，该提议的假设是SFK激活蛋白酶体。通过使用小分子抑制剂和siRNA介导的敲低，将在DLBCL细胞中抑制SFK，之后将在蛋白酶体活性、蛋白质表达、基因表达和蛋白质翻译后修饰中的变化被抑制。 评估。随后的研究将检查相同的变化后，激活一个或多个SFK成员通过表达的组成型活性结构。这项工作将为DLBCL中SFK-蛋白酶体信号转导轴提供有价值的见解，因此将更好地了解导致DLBCL中肿瘤进展和耐药性的细胞过程。这项研究的结果可能会导致确定其他治疗复发性和难治性DLBCL的治疗靶点。