Fully Synthetic Prodiginines as Probes of Protein-Protein Interactions Regulating

全合成 Prodiginines 作为蛋白质-蛋白质相互作用调节探针

基本信息

批准号：
9228341
负责人：
Patrick G. Harran
金额：
$ 35.21万
依托单位：
UNIVERSITY OF CALIFORNIA LOS ANGELES
依托单位国家：
美国
项目类别：
财政年份：
2014
资助国家：
美国
起止时间：
2014-04-16 至 2019-02-28
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9228341
关键词：
Affinity Apoptosis Apoptotic Attention Avidity BCL-2 Protein BCL2 gene Bacteria Binding Binding Sites Biochemical Biological Assay Caspase Cell Culture Techniques Cell Death Cell Death Signaling Process Cell Membrane Permeability Cells Cessation of life Chemistry Clinic Clinical Trials Collaborations Competitive Binding Complex Computer Simulation Crystallography Custom Data Defect Defense Mechanisms Development Disease Docking Drug Targeting Drug resistance Evaluation Family Goals Human Human Cell Line In Vitro Ion Transport Ions Laboratories Ligands Liposomes Lymphoblastic Leukemia Malignant Neoplasms Marines Metals Methods Mitochondria NCI Center for Cancer Research Natural Products Normal Cell Outer Mitochondrial Membrane Pathway interactions Pharmacology Pigments Process Property Protein Family Reactive Oxygen Species Recombinants Research Resistance Roentgen Rays Route Set protein Signaling Protein Structure Surface Synthesis Chemistry System TP53 gene Technology Testing Universities Variant alpha helix analog base cancer cell cellular targeting chemotherapy chromophore cytotoxic cytotoxicity design drug development experimental study flexibility functional genomics in vivo killings mimetics mimicry novel overexpression pH gradient peptidomimetics prodiginine professor programs protein expression protein protein interaction public health relevance radioresistant release factor scaffold small molecule targeted agent therapeutic development

项目摘要

DESCRIPTION (provided by applicant): Reestablishing apoptosis in cancer cells holds considerable promise for targeted, non-toxic therapy. We demonstrated this previously with the development of 'smac mimetics', small molecules that disrupt protein- protein interactions that suppress proper caspase activation. Smac mimetics from several organizations have since advanced to human clinical trials. These experiments remain ongoing. In this proposal we outline new chemistry aimed at a second set of protein-protein interactions that block apoptosis in cancer and contribute to drug resistance. Bcl-2 family proteins gate mitochondrial outer membrane permeability and regulate cytoplasmic release of factors essential for normal cell death. Over-expression of anti-apoptotic Bcl-2 proteins is common in chemotherapy and radiation resistant cancers. As a result, the Bcl-2 system has been intensely studied as a target for drug development. The most advanced of these efforts have reached clinic stages. However, despite tremendous promise for the mechanism, unanticipated off-target effects and, notably, Mcl-1 based resistance to agents targeting Bcl-XL are limiting progress. New compounds with superior profiles are needed. Ansa-bridged prodiginines are cytotoxic pigments produced by bacteria. One of these natural products, streptorubin B, was identified by Shore as a molecule that potentiates apoptosis in cell culture - reportedly through interactions with Bcl-2 proteins. This observation seeded development of obatoclax, a synthetic prodiginine now in clinical trials as therapy for lymphocytic leukemia. Obatoclax is described as a pan Bcl-2 antagonist that targets BH3 helix-binding surfaces, including the Noxa binding site on Mcl-1. Data is promising but tempered by selectivity. The tri-pyrrolic chromophore in obatoclax generates ROS in the presence of metal ions and can neutralize pH gradients via transmembrane ion transport. Both effects damage normal cells. We propose to study new pyrrolophane variants of streptorubin B that lack the structural liabilities of obatoclax. Based on our recently completed total synthesis f roseophilin, we outline new methods to synthesize marineosins A and B - newly isolated anti-leukemic prodiginines produced by marine bacteria. In collaboration with Gordon Shore at McGill University, we have discovered intermediates in our roseophilin synthesis that block t-Bid dependent Mcl-1 functions in vitro. We propose to build on these results by advancing our synthetic chemistry along several lines. Based on computational models, we believe the ansa- bridged heterocyclic cores of the natural products in question can scaffold a new class of �-helix peptidomimetics. Experiments to test this hypothesis are described. These include custom syntheses of ligands targeting the Mcl-1/Noxa, Bcl-XL /Bim and p53/mdm2 interactions selectively. Lastly, as means to identify non Bcl-2 based effects in cell culture and in vivo, we propose to search for additional targets of this structural class using affinity based biochemical methods and state-of-the-art functional genomic screens.

描述（由适用提供）：癌细胞中凋亡的重新凋亡对靶向的无毒疗法具有相当大的希望。我们以前通过“ SMAC Mimetics”的发展证明了这一点，即破坏抑制适当caspase激活的蛋白质相互作用的小分子。此后，来自几个组织的SMAC Mimetics已晋升为人类临床试验。这些实验仍在进行中。在此提案中，我们概述了针对第二组蛋白质蛋白质相互作用的新化学反应，这些蛋白质蛋白质相互作用阻断了癌症的凋亡并有助于耐药性。 Bcl-2家族蛋白栅极线粒体外膜的渗透性和调节正常细胞死亡必不可少的因子的细胞质释放。抗凋亡Bcl-2蛋白的过表达在化学疗法和抗辐射癌中很常见。结果，BCL-2系统已被积极研究为药物开发的目标。这些努力中最先进的已经进入了诊所阶段。然而，尽管对该机制有很大的希望，意外的脱靶效应以及尤其是基于MCL-1的对靶向BCL-XL的药物的抗性仍在限制进展。需要具有出色配置的新化合物。 ANSA桥的质量是细菌产生的细胞毒性色素。这些天然产物之一，链霉素B，通过海岸鉴定为一种分子，据报道通过与Bcl -2蛋白的相互作用来潜在细胞培养中的细胞凋亡。这一观察结果是Obatoclax的种子发展，Obatoclax是一种临床试验中的合成质质蛋白，作为淋巴细胞性白血病的治疗。 obatoclax被描述为靶向BH3螺旋结合表面的PAN BCL-2拮抗剂，包括MCL-1上的NOXA结合位点。数据是有希望的，但被选择性降低了。 obatoclax中的三吡咯发色团在金属离子存在下产生ROS，并可以通过跨膜离子转运中和pH梯度。两种影响都会损害正常细胞。我们建议研究缺乏obatoclax结构性负债的链球菌B的新吡咯烷变体。基于我们最近完成的总合成F玫瑰油蛋白，我们概述了合成海洋学A和B的新方法 - 海洋细菌产生的新近分离的抗白血病。在麦吉尔大学（McGill University）的戈登海岸（Gordon Shore）合作，我们发现了我们的玫瑰酚蛋白合成中的中间体，这些中间体在体外阻止了T-bid依赖的Mcl-1功能。我们建议通过沿着几条线推进我们的合成化学来建立这些结果。根据计算模型，我们认为有关天然产品的ANSA-BRIDRIDRID杂环核可以脚阻塞一类新类的 - 螺旋肽肽仪。描述了检验该假设的实验。其中包括针对MCL-1/NOXA，BCL-XL/BIM和P53/MDM2相互作用的配体的自定义合成。最后，作为确定基于细胞培养和体内的非基于BCL-2的效果的方法，我们建议使用基于亲和力的生化方法和最先进的功能基因组筛选来搜索该结构类别的其他目标。