Methodology for Identification of Substrate-Competitive Kinase Inhibitors

描述(申请人提供)：蛋白酪氨酸激酶(PTK)在细胞信号和调节生物过程中发挥关键作用，如增殖、分化和凋亡。超过164种蛋白激酶与癌症、炎症、糖尿病、高血压、血管生成和免疫疾病等疾病有关。直接或间接地，已有400多种疾病与蛋白激酶有关。有鉴于此，PTK已成为学术界和制药业具有吸引力的药物开发靶点。然而，尽管有大量的靶点，FDA批准的激酶抑制药以及那些正在临床开发的药物只针对少数几个通过与ATP竞争而提供抑制作用的众所周知的激酶。显然，获得针对多种酪氨酸激酶的有效和选择性的ATP竞争性化合物一直是困难的。这项建议旨在开发通用和强大的工具，以快速识别底物竞争性蛋白酪氨酸激酶(PTK)抑制剂。目前已批准的所有针对与疾病相关的PTKs抑制的治疗药物都是ATP竞争性抑制剂。然而，我们认为PTKs的底物竞争抑制比ATP竞争抑制有几个重要的好处。由于PTK之间的ATP结合口袋具有很高的相似性，获得选择性抑制尤其具有挑战性。选择性地抑制靶蛋白激酶将最大限度地减少治疗药物的非靶点副作用，并为生物学研究提供选择性的化学探针。底物竞争抑制剂代表了由于PTKs的非同源底物口袋而导致的选择性激酶抑制的进展。我们计划使用四个初始靶点来开发我们的方法学：c-Abl、c-Src和锥体中的两个必需的酪氨酸激酶。C-Abl和c-Src都与癌症进展有关(分别是慢性粒细胞白血病(CML)和结肠癌的有效靶点)，锥虫PTKs是治疗非洲昏睡病(人类非洲锥虫病，HAT)的潜在靶点。慢性粒细胞白血病是一种罕见的无法手术的癌症，在美国每年导致5000多例新病例。结肠癌是第三种最常见的癌症，每年导致超过65万人死亡。非洲昏睡病在西非是一个日益严重的问题，每年导致30万新病例和6万多人死亡。我们相信，这项拟议的研究非常适合尤里卡计划，因为：1)它开发了尖端方法，通过ATP竞争性化合物挑战广泛存在的激酶抑制范式；2)创建了一个灵活而强大的平台，用于获得针对参与疾病进展的任何激酶靶标的底物竞争性激酶抑制剂。公共卫生相关性：直接或间接地，有400多种疾病与蛋白激酶有关。我们的目标是开发化学工具来识别底物竞争性激酶抑制剂。我们的方法最初将重点放在两个与癌症有关的激酶(c-Abl和c-Src)和两个与非洲昏睡病有关的激酶上。

DESCRIPTION (provided by applicant): Protein tyrosine kinases (PTKs) play a key role in cell signaling and regulating biological processes such as proliferation, differentiation, and apoptosis. More than 164 protein kinases have been implicated in diseases including cancer, inflammation, diabetes, hypertension, angiogenesis, and immune disease. Directly or indirectly, over 400 diseases have been linked to protein kinases. In light of this, PTKs have become attractive targets for drug development in both academia and the pharmaceutical industry. Despite the large number of targets, however, the FDA-approved kinase inhibitiors as well as those in clinical development target only a handful of well-known kinases providing inhibition via competition with ATP. Clearly, obtaining potent and selective ATP-competitive compounds against a wide-variety of tyrosine kinases has been difficult. This proposal aims to develop general and robust tools for the rapid identification of substrate-competitive protein tyrosine kinase (PTK) inhibitors. All current approved therapeutics targeting inhibition of PTKs involved in disease are ATP-competitive inhibitors. However, we believe that substrate-competitive inhibition of PTKs offers several important benefits over ATP-competitive inhibition. Due to very high similiarity in the ATP binding pocket across PTKs, obtaining selective inhibition is particularly challenging. Selective inhibition of a target kinase will minimize off-target side-effects of therapeutics as well as provide selective chemical probes for biological studies. Substrate-competitive inhibitors represent an advance toward selective kinase inhibition owing to the non-homologous substrate pocket of PTKs. We plan to develop our methodology using four initial targets: c-Abl, c-Src, and two essential tyrosine kinases in Trypanosomes. c-Abl and c-Src are both involved in cancer progression (validated targets for chronic myelogenous leukemia (CML) and colon cancer, respectively) and the Trypanosome PTKs are potential therapeutic targets for African sleeping sickness (human African trypanosomiasis, HAT). CML is a rare, inoperable cancer which results in more than 5,000 new cases per year in the United States. Colon cancer is the third most common cancer, resulting in over 650,000 deaths per year. African sleeping sickness is a growing problem in western Africa, resulting in 300,000 new cases per year and over 60,000 deaths per year. We believe the proposed research is well-suited for the EUREKA program because: 1) it develops cutting- edge methodologies which challenge the widespread paradigm of kinase inhibition via ATP-competitive compounds, and 2) creates a flexible and robust platform for obtaining substrate-competitive kinase inhibitors against any kinase target involved in disease progression. PUBLIC HEALTH RELEVANCE: Directly or indirectly, over 400 diseases have been linked to protein kinases. We aim to develop chemical tools to identify substrate-competitive kinase inhibitors. Our methodology will initially focus on two kinases involved in cancer (c-Abl and c-Src) and two kinases involved in African sleeping sickness.