Methodology for Identification of Substrate-Competitive Kinase Inhibitors

描述（由申请人提供）：蛋白酪氨酸激酶（PTKs）在细胞信号传导和调节增殖、分化和凋亡等生物过程中发挥关键作用。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，400多种疾病与蛋白激酶有关。有鉴于此，PTKs已成为学术界和制药行业药物开发的有吸引力的靶点。然而，尽管有大量的靶点，fda批准的激酶抑制剂以及临床开发的激酶抑制剂仅针对少数众所周知的通过与ATP竞争提供抑制的激酶。显然，获得针对多种酪氨酸激酶的有效和选择性的atp竞争化合物是困难的。本提案旨在开发通用且强大的工具，用于快速鉴定底物竞争性蛋白酪氨酸激酶（PTK）抑制剂。目前所有被批准的靶向抑制疾病相关PTKs的治疗方法都是atp竞争性抑制剂。然而，我们认为底物竞争性抑制PTKs比atp竞争性抑制有几个重要的好处。由于ATP结合袋在PTKs中的高度相似性，获得选择性抑制是特别具有挑战性的。选择性抑制靶激酶将最大限度地减少治疗的脱靶副作用，并为生物学研究提供选择性化学探针。由于PTKs的非同源底物袋，底物竞争性抑制剂代表了选择性激酶抑制的进展。我们计划使用四个初始靶点：c-Abl、c-Src和锥虫体内的两种必需酪氨酸激酶来开发我们的方法。c-Abl和c-Src都参与癌症进展（分别是慢性粒细胞白血病（CML）和结肠癌的有效靶点），锥虫PTKs是非洲昏睡病（人类非洲锥虫病，HAT）的潜在治疗靶点。慢性粒细胞白血病是一种罕见的，不能手术的癌症，在美国每年有超过5000例新病例。结肠癌是第三大最常见的癌症，每年导致65万多人死亡。非洲昏睡病在西非是一个日益严重的问题，每年造成30万新病例，6万多人死亡。我们相信这项研究非常适合EUREKA项目，因为：1)它开发了尖端的方法，挑战了通过atp竞争化合物进行激酶抑制的广泛范例；2)为获得底物竞争的激酶抑制剂创建了一个灵活而强大的平台，可以对抗任何参与疾病进展的激酶靶点。公共卫生相关性：400多种疾病直接或间接与蛋白激酶有关。我们的目标是开发化学工具来鉴定底物竞争性激酶抑制剂。我们的方法将首先关注与癌症有关的两种激酶（c-Abl和c-Src）和与非洲昏睡病有关的两种激酶。

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.