Selective disruption of histone deacetylase complexes using protein interaction modulators

项目摘要 确定新疗法的策略通常包括靶向参与相关的酶活性 生物途径，假设这种方法最有可能识别出有效、安全和生物可用的 毒品。这一概念与表观遗传扰动的发展特别相关，如组蛋白 脱乙酰酶(HDAC)抑制剂，或“HDACis”。FDA批准的所有七种HDACI都以类似的方式绑定到 杂乱无章的脱乙酰酶酶口袋。当这种“酶抑制物”化合物被成功使用时 在治疗T细胞淋巴瘤和多发性骨髓瘤方面，它们在治疗其他类型的癌症方面仍然有限。 目前可用的HDACis的主要限制之一是，通过系统地靶向HDAC酶 它们几乎没有表现出对负责调节不同 因此，它们会影响很大一部分基因的转录调控。 转录组。我们在这里的目标是开发一个替代模型，根据这个模型，蛋白质相互作用 调节剂扰乱HDAC亚复合体亚群中的特定蛋白质相互作用，因此有许多 与传统的HDACis相比，对处理细胞转录组的影响更小。这一点的中心假设是 模型是，扰动细胞中特定的HDAC亚复合体而不是所有的HDAC复合体可能会导致 转录效应范围小得多，但仍具有强大的抗肿瘤作用(图1)。为了测试这一点 假设，我们提出了以下三个具体目标。 目的1.确定非酶亚基的小分子扰动程度 HDAC复合体可影响其抑制功能。我们的目标是确定一个新的HDAC类别 调节剂，它不是针对酶口袋，而是影响HDAC的其他更具体的功能 复合体。 目的2.比较HDAC非酶和酶小分子的整体转录效应。 分子微扰。我们的中心假设的一个分支是，应该有可能识别HDAC 复杂的调节剂，导致转录效应比传统的转录效应要小得多 HDAC酶抑制剂。在这里，我们将确定HDAC亚复合体调节剂的转录组效应 调查这些新化合物对转录组的影响有多广或多窄。 目的3.验证HDAC复合体的启动子占位扰动可以有效地 消灭致瘤表型。我们将测试对特定的HDAC亚复合体的干扰程度 比所有细胞HDAC复合体，虽然导致转录效应要小得多，但可能 具有强大的抗肿瘤作用。 简而言之，我们建议不像传统的HDAC抑制剂那样影响细胞中的所有HDAC活性， 可以确定一类新的蛋白质相互作用调节剂，它们影响特定的HDAC亚复合体。

Project Summary Strategies to identify novel therapeutics typically include targeting enzymatic activities involved in relevant biological pathways, with the assumption that this approach will most likely identify potent, safe, and bioavailable drugs. This concept is particularly relevant to the development of epigenetic perturbants such as histone deacetylase (HDAC) inhibitors, or “HDACis”. All seven FDA-approved HDACis bind in similar ways to promiscuous deacetylase enzymatic pockets. While such “enzymatic inhibitor” compounds are used successfully to treat T cell lymphomas and multiple myelomas, they remain limited in addressing other types of cancers. One of the major limitations of currently available HDACis is that, by systematically targeting HDAC enzymatic pockets, they show little specificity for various HDAC complexes responsible for the regulation of different subsets of genes, and consequently, they affect the transcriptional regulation of a large portion of the transcriptome. Our goal here is to develop an alternative model according to which “protein interaction modulators” perturb specific protein interactions in subsets of HDAC subcomplexes and thus have much narrower effects on the transcriptome of treated cells than conventional HDACis. The central hypothesis of this model is that perturbing specific HDAC subcomplexes rather than all HDAC complexes in a cell might result in much narrower transcriptional effects and yet confer potent anti-tumorigenic effects (Fig. 1). To test this hypothesis, we propose the three following specific aims. Aim 1. To determine the extent to which small-molecule perturbations of non-enzymatic subunits of HDAC complexes can affect their repressing functions. Our goal is to identify a new class of HDAC modulators, which, instead of targeting enzymatic pockets, would affect other, more specific functions of HDAC complexes. Aim 2. To compare global transcriptomic effects of HDAC non-enzymatic versus enzymatic small- molecule perturbations. One branch of our central hypothesis is that it should be possible to identify HDAC complex modulators that result in much narrower transcriptional effects than those observed with conventional HDAC enzymatic inhibitors. Here we will determine transcriptome-wide effects of HDAC subcomplex modulators to investigate how widely or narrowly these new compounds affect the transcriptome. Aim 3. To test the hypothesis that promoter occupancy perturbations of HDAC complexes can potently abrogate tumorigenic phenotypes. We will test to what extent perturbing specific HDAC subcomplexes rather than all cellular HDAC complexes, while resulting in much narrower transcriptional effects, might nevertheless confer potent anti-tumorigenic effects. In short, we propose that instead of affecting all HDAC activities in the cell as conventional HDAC inhibitors do, a new class of protein interaction modulators can be identified that affect specific HDAC subcomplexes.