Project 2: Development of grp94-selective Inhibitors for Cancer

项目2：grp94选择性癌症抑制剂的开发

基本信息

批准号：
8934514
负责人：
GABRIELA CHIOSIS
金额：
$ 30.44万
依托单位：
MEDICAL UNIVERSITY OF SOUTH CAROLINA
依托单位国家：
美国
项目类别：
财政年份：
2015
资助国家：
美国
起止时间：
2015-09-01 至 2020-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8934514
关键词：
Address Advanced Malignant Neoplasm Affinity Animals Back Biochemical Biology Blood Breast Cancer Treatment Cancer Biology Cell Line Cell membrane Cells Characteristics Chemicals Client Clinic Clinical Complement Data Development Disease Disease Resistance ERBB2 gene Endoplasmic Reticulum Environment Evaluation Family Genes Genetic Glucose Goals Heat shock proteins Heat-Shock Proteins 90 Homologous Gene Housing Integrins Investigation Label Lead Ligands Link Maintenance Malignant Neoplasms Mediating Medical Research Mitochondria Molecular Chaperones Mus Nature Oncogenic Organism Pathway interactions Pharmaceutical Preparations Pharmacology Phenotype Protein Overexpression Protein Tyrosine Kinase Proteins Proteome Reagent Refractory Research Role Signal Transduction Solid System TNF receptor-associated factor 1 Therapeutic Toll-like receptors Translating Translations Yeasts anti-cancer therapeutic base cancer cell cancer therapy cellular engineering combinatorial design drug development drug discovery genetic approach improved in vivo inhibitor/antagonist malignant breast neoplasm malignant phenotype mutant novel overexpression paralogous gene pressure programs receptor screening small molecule small molecule libraries spatiotemporal targeted cancer therapy targeted treatment therapy design therapy resistant tool tumor

项目摘要

PROJECT SUMMARY Background and hypothesis: While grp94 expression in cancer is linked to aggressive disease and resistance to therapy, little is known on mechanisms underlying these effects. Our inability to study grp94 in genetically tractable organisms such as yeast and the unavailability of small molecule grp94 inhibitors are largely responsible for this state of affairs. Until now investigation of grp94 has mainly used mutant cell lines and gene deficient mouse studies. Although powerful, this approach is limited because it addresses phenotypic changes in the complete absence of a gene, and moreover, makes use of an engineered cellular environment. Alternative strategies that address the role and biology of grp94 in an endogenous cellular environment, where grp94 is limiting but not absent, are therefore needed. In addition to linking grp94-mediated mechanisms to the relevant disease state, i.e. tumor type, these reagents may provide evidence refractory to the currently available means. Approach: Discovery of grp94-selective ligands and chemical tools has been challenging thus far because of a high degree of analogy between the HSP90 paralogs. We here provide preliminary evidence showing that the discovery of grp94 inhibitors with log selectivity over the other paralogs is possible. Using a combination of screening an in-house generated small-molecule library and computational analyses backed by structural studies conducted with Project 3, we have identified important structural determinants that impart ligand selectivity and high affinity for grp94. We propose to use this information as a springboard for the development of grp94-directed chemical tools such as grp94 selective ligands and solid support immobilized, biotinylated and fluorescently labeled derivatives (Aim 1a) and as a starting point towards the development of drug-like grp94 inhibitors for translation to clinic as novel anti-cancer therapeutics (Aim 1b). We also propose here to use the grp94-directed toolset for the investigation of disease-specific roles of grp94 (Aim 2). Significance: In support of this investigative chemical biology approach, we provide preliminary data that confirm its power. We show that it identifies a novel role for grp94 in regulating HER2 tyrosine kinase at the plasma membrane, specifically in the case of tumors with overexpression of this protein. Also we implicate grp94 in regulating oncogenic signal transduction at the plasma membrane, indicating grp94 as a target in HER2-overexpressing breast cancer. These findings provide the blueprint for the development of grp94 inhibitors as a novel targeted therapy for the treatment of breast cancers dependent on increased signaling through plasma membrane receptors. Importantly, although HER2 was for the last two decades one of the most widely studied HSP90 onco-client protein, the mechanistic and the therapeutic understanding unveiled by our chemical biology approach was missed so far, proving further evidence to the importance of having a strong chemical toolset in addition to genetic and biochemical means for the understanding of biology.

项目概要背景和假设：虽然癌症中 grp94 的表达与侵袭性疾病和尽管对治疗产生耐药性，但人们对这些效应背后的机制知之甚少。我们无法研究 grp94 酵母等遗传易驯化的生物体以及小分子 grp94 抑制剂的不可用性造成这种状况的主要原因。迄今为止对grp94的研究主要使用突变细胞系和基因缺陷小鼠研究。尽管功能强大，但这种方法有局限性，因为它解决了表型问题在完全没有基因的情况下发生变化，而且利用了工程化的细胞环境。解决 grp94 在内源细胞环境中的作用和生物学的替代策略，其中 grp94 是有限制的，但并非不存在，因此是需要的。除了将 grp94 介导的机制与相关疾病状态，即肿瘤类型，这些试剂可能提供目前难以处理的证据可用的手段。方法：迄今为止，发现 grp94 选择性配体和化学工具一直具有挑战性因为 HSP90 旁系同源物之间具有高度相似性。我们在这里提供初步证据表明发现与其他旁系同源物相比具有对数选择性的 grp94 抑制剂是可能的。使用结合筛选内部生成的小分子库和由通过项目 3 进行的结构研究，我们确定了重要的结构决定因素，这些因素赋予配体选择性和对 grp94 的高亲和力。我们建议将此信息用作跳板开发grp94导向的化学工具，例如grp94选择性配体和固定的固体支持物，生物素化和荧光标记的衍生物（目标 1a）并作为开发的起点类药物 grp94 抑制剂作为新型抗癌疗法转化为临床（目标 1b）。我们还建议这里使用 grp94 导向的工具集来研究 grp94 的疾病特异性作用（目标 2）。意义：为了支持这种化学生物学研究方法，我们提供了初步数据证实了它的力量。我们证明它确定了 grp94 在调节 HER2 酪氨酸激酶中的新作用质膜，特别是在这种蛋白质过度表达的肿瘤的情况下。我们还暗示 grp94 调节质膜上的致癌信号转导，表明 grp94 是 HER2 过度表达乳腺癌。这些发现为grp94的开发提供了蓝图抑制剂作为一种新型靶向疗法，用于治疗依赖信号增强的乳腺癌通过质膜受体。重要的是，尽管 HER2 在过去二十年中一直是研究最广泛的 HSP90 肿瘤客户蛋白，揭示了其机制和治疗理解到目前为止，我们的化学生物学方法被错过了，这进一步证明了拥有化学生物学方法的重要性除了遗传和生化手段之外，还有强大的化学工具集用于理解生物学。