Development of Allosteric Modulators of Phosphatidylinositol 3-Kinase

项目摘要 大多数激酶抑制剂针对的是三磷酸腺苷结合部位，并经常抑制人体内的许多激酶。 金诺姆。由于泛激酶抑制剂的性质，在临床前经常观察到严重的副作用。 和临床研究。因此，为了实现安全有效的治疗，需要更具体的治疗方法。 人类疾病。变构调节剂(激动剂和拮抗剂)比ATP- 竞争性抑制剂由于变构结合部位保守得多而实现选择性。高和 变构调节剂也可以获得一致的效价。此外，变构调节剂可以 与ATP竞争性相比，在细胞和体内显示不同的疗效和药理作用 抑制剂。这些试剂可用于研究激酶的特定生物学和病理功能。 在人类疾病方面。然而，鉴定变构先导化合物及其结合口袋是一个很好的方法 阻碍激酶变构调节剂发展的挑战。因此，在这个奖项中，一个新的概念 并提出了几种开发磷脂酰肌醇3-激酶变构调节剂的方法 (PI3Kα)，它与人类癌症、新陈代谢、先天性和获得性免疫以及自闭症谱系有关 无序。捕获在激活域和RAS结合界面上的多肽片段 以PI3Kα结构域为变构起始化合物，合成PI3Kα的变构调节剂。 我们的早期初步研究支持了我们的假设，并为 PI3Kα变构激动剂和拮抗剂的研究进展因此，我们将开发高度有效的变构 应用链接子搜索、支架等结构导向药物设计技术构建PI3Kα调节子 跳跃，以及虚拟合成和筛选(目标1)。固相法多肽合成及溶液相 有机合成将被应用于生成多肽模拟库和一系列小分子 分别是相似的。PI3K-α与变构调节剂形成的络合物的X射线共晶结构 确定并用于基于结构的设计。一旦低纳米分子的抑制和激活 在生化分析中，变构调节剂的细胞效力将在一系列细胞- 基于增殖和功能分析(目标2)。此外，PI3Kα介导的细胞信号通路 将结合使用高效变构调节剂和ATP竞争性抑制剂进行研究。 总而言之，拟议的研究将在以下方面对生物医学研究和药物发现产生重大影响 提出了一种新的发现变构调节剂的概念。这个 本项目开发的变构调节剂将有助于研究新的激酶功能。 通过PI3Kα来确定其在人类疾病中的具体作用和要求。最后，概念和 该项目建立的技术将为发现变构调节剂提供坚实的战略。 激酶和大量新的化学物质在激酶药物发现中的作用。

Project Summary Most kinase inhibitors target the ATP binding site, and frequently inhibit numerous kinases in the human kinome. Due to the nature of pan-kinase inhibitors, severe side effects are frequently observed in pre-clinical and clinical studies. Therefore, more specific therapeutics are desirable to achieve safe and effective treatment of human diseases. Allosteric modulators (agonists and antagonists) have greater potential than ATP- competitive inhibitors to achieve selectivity due to the much less conserved allosteric binding sites. High and consistent potency can also be achieved by the allosteric modulators. Furthermore, allosteric modulators can show different efficacies and pharmacological effects in cell and in vivo, compared to ATP competitive inhibitors. These agents can be applied to investigate specific biological and pathological functions of kinases in human diseases. However, identifying allosteric lead compounds and their binding pockets is a great challenge that retards the development of allosteric modulators of kinases. So, in this Award a novel concept and several approaches are proposed to develop allosteric modulators of Phosphatidylinositol 3-Kinase (PI3Kα), which is involved in human cancer, metabolism, innate and adaptive immunity, and Autism spectrum disorder. The peptide fragment trapped at the interface between the kinase domain and the Ras binding domain of PI3Kα was employed as an allosteric starting compound to generate allosteric modulators of PI3Kα. Our early stage pilot studies supported our hypothesis and produced proper starting agents for the development of allosteric agonists and antagonists of PI3Kα. Therefore, we will develop highly potent allosteric modulators of PI3Kα by applying structure-guided drug design techniques such as linker search, scaffold hopping, and virtual synthesis and screening (Aim 1). Solid phase peptide synthesis and solution phase organic synthesis will be applied for generating a peptidomimetic library and a series of small molecule analogs, respectively. X-ray co-crystal structures of PI3Kα in complex with allosteric modulators will be determined and used for the structure-based design. Once low nanomolar inhibition and activation are achieved in biochemical assays, cellular potency of allosteric modulators will be assessed in a series of cell- based proliferation and functional assays (Aim 2). Furthermore, cellular signaling pathways mediated by PI3Kα will be investigated with highly potent allosteric modulators in combination with ATP-competitive inhibitors. In summary, the proposed research will have high impact on biomedical research and drug discovery in terms of new types of chemical entities in kinases and a new concept for the discovery of allosteric modulators. The allosteric modulators developed in this project will facilitate the investigation of new kinase functions mediated by PI3Kα to determine its specific roles and requirement in human diseases. Finally, the concepts and techniques established in this project will provide solid strategies for discovery of allosteric modulators of kinases and a large pool of new chemical entities in kinase drug discovery.