Mutations of Chromatin and its Modifying Machineries in Malignancies

项目摘要 我实验室的集体研究集中在功能的分子表征上， 表观遗传修饰物的生物化学性质和与人类癌症相关的突变。 我们的目标是确定这些因子的突变如何在分子上改变基因的模式， 表达导致细胞过度增殖，并使用这些分子途径来鉴定靶向的 癌症的治疗方法。我们在过去七年中获得这笔赠款支持的详细结构研究 R35 CA 197569允许我们识别Set 1/COMPASS的原子结构，并基于此 信息，我们已经产生了抑制剂对它的活动，现在正在我们的实验室开发， 调节COMPASS在细胞中功能的工具化合物，最终用于临床。在其他方面， 对MLL 3/COMPASS作用的分析表明它与组蛋白去泛素化酶相互作用 BAP 1，在增强子处提供中心表观遗传平衡并调节癌症中的基因表达 这是MLL 3突变的结果。基于这些信息，我们在西北大学进行了一项临床试验 研究这种平衡在癌症治疗中的表观遗传作用的医学。我们还生成了BAP 1 抑制剂，可以调节由于ASXL 1突变引起的癌症中过度活化的BAP 1功能 我们的实验室正在进一步研究这种BAP 1抑制剂作为生物化学和临床工具。我们 详细分析组蛋白H3 K27 M突变在弥漫性内在脑桥胶质瘤（DIPG）中的作用， 鉴定含BET结构域的因子如Brd 2和Brd 4在DIPG发病机制中的作用。我们 正在与芝加哥卢里儿童医院的同事合作，在临床上测试这些发现。这些 研究还鉴定了CATACOMB作为模拟H3 K27 M的内源性因子， 调节PRC 2功能。如本申请中将描述的，实验室中的其他研究已经探索了 在发育调节和癌症中不同表观遗传因素的机械特性。此外，本发明还 最近对癌症和自然衰老过程中的体细胞突变的编目已经确定了大量的 MLL 1 -4、UTX、Set 1A/B和其他表观遗传因子的组分中的突变。鉴于我们有 在过去的二十年里，我们在实验室里针对这些因素开发了一套很棒的试剂和工具， 他们的相关蛋白质，染色质和其他染色质修饰剂在多个模型系统，我的实验室是 在确定这些因素参与癌症的分子基础方面处于非常独特和强有力的地位 发病机理，并因此用于靶向治疗的目的。此R35更新应用程序的目标 是我们对三胸龟COMPASS的完整分子和生物化学表征的延续 家族和BAP 1复合物在发育基因表达调控中的作用，以及它们如何 突变有助于人类癌症的发病机制。

Project Summary Collective studies from my laboratory have focused on the molecular characterization of the function(s) and biochemical properties of the epigenetic modifiers and the mutations that are associated with human cancer. Our goal has been to determine how the mutations in these factors molecularly change the pattern of gene expression resulting in cellular hyperproliferation and use these molecular pathways to identify targeted therapeutics for cancer. Our detailed structural studies supported during the past seven years by this grant R35CA197569 have allowed us to identify the atomic structure of Set1/COMPASS, and based on this information, we have generated inhibitors towards its activity that are now being developed in our laboratory as a tool compound to regulate COMPASS's function in cells for the ultimate use in clinic. On other fronts, our analyses of the role of MLL3/COMPASS identified its interactions with the histone deubiquitinating enzyme BAP1, providing a central epigenetic balance at enhancers and the regulation of gene expression in cancer caused as the result of MLL3 mutations. Based on this information, we have a clinical trial at Northwestern Medicine investigating the epigenetic role of this balance in cancer therapy. We have also generated BAP1 inhibitors that can regulate hyperactivated BAP1 function in cancers caused as the result of ASXL1 mutations and such BAP1 inhibitors are being further investigated in our laboratory as biochemical and clinical tools. Our detailed analysis of the role of histone H3K27M mutations in diffuse intrinsic pontine gliomas (DIPG) resulted in the identification of a role for BET-domain containing factors such as Brd2 and Brd4 in DIPG pathogenesis. We are collaborating with colleagues at Lurie Children's Hospital of Chicago to test these findings in clinic. These studies also resulted in the identification of CATACOMB as an endogenous factor mimicking H3K27M and regulating PRC2 function. As will be described in the application, other studies in the laboratory have probed the mechanistic properties of diverse epigenetic factors in developmental regulation and in cancer. Additionally, recent cataloging of somatic mutations in cancer and during natural aging has identified a large number of mutations in the components of the MLL1-4, UTX, Set1A/B, and other epigenetic factors. Given that we have developed a fantastic set of reagents and tools over the past twenty years in our laboratory towards these factors, their associated proteins, chromatin, and other chromatin modifiers in multiple model systems, my laboratory is in a very unique and strong position to define the molecular bases of these factors’ involvement in cancer pathogenesis, and thus, for the purpose of targeted therapeutics. The goals of this R35 renewal application are the continuation of our full molecular and biochemical characterization of the trithorax COMPASS family and BAP1 complexes in the regulation of developmental gene expression, and how their mutations contribute to the pathogenesis of human cancer.