Development of small molecule inhibitors of protein kinase D

描述(申请人提供)：蛋白激酶D(PKD)是一个新的家族的关键第二信使二酰甘油靶标，可被G蛋白偶联受体激动剂和生长因子激活。PKD家族--PKD-1、2和3--在许多基本的细胞过程中发挥着重要作用。PKD的去调控与多种病理条件和癌症有关。然而，缺乏PKD特异的抑制物严重阻碍了我们理解PKD特异的信号通路和生物学功能以及在人类疾病中靶向PKD的能力。我们最近报道了第一个有效的和选择性的PKD小分子抑制剂：苯并恶氮卓酮CID755673，它是通过对196,173个化合物的高通量筛选而鉴定出来的。CID755673是一种具有亚微摩尔效力的PAN-PKD抑制剂。它具有细胞活性，阻断了PKD的已知生物学行为，抑制了前列腺癌细胞的增殖、迁移和侵袭等与癌症相关的特性。重要的是，该抑制剂在酶抑制方面不与ATP竞争，与包括CAMKII1、AKT、PKA和几种PKC亚型在内的至少20种不同的激酶相比，对PKD具有高度的选择性。最关键的是，CID755673的结构优化得到了一种新型的苯并噻吩衍生物Kb-NB142-70，它具有低纳摩尔活性和更高的PKD选择性。我们假设CID755673可以优化为一类新型的PKD抑制剂，具有独特的作用机制，能够有效和选择性地阻断PKD功能。我们的长期目标是建立一种系统的方法来开发CID755673衍生的探针分子作为创新的PKD抑制剂。我们提出的研究策略侧重于CID755673及其类似物的先导优化、机理评价和体内疗效评价。提出了三个具体目标，代表了开发治疗PKD的有效和选择性药物消融剂的第一个主要努力：目标1.通过结构修改优化CID755673，以获得更有效和选择性的衍生物。目的2.确定CID755673及其类似物对PKD具有良好选择性的分子机制。目的3.在体内验证CID755673及其衍生物可有效和选择性地阻断PKD功能的假设。

DESCRIPTION (provided by applicant): Protein kinase D (PKD) is a novel family of the key second messenger diacylglycerol targets that can be activated by G-protein coupled receptor agonists and growth factors. The family of PKD - PKD1, 2 and 3 - plays important roles in many fundamental cellular processes. Deregulation of PKD has been implicated in multiple pathological conditions and cancer. However, the lack of a PKD-specific inhibitor has severely impeded our ability to understand PKD-specific signaling pathways and biological functions and to target it in human diseases. We have recently reported the first potent and selective small molecule inhibitor for PKD: benzoxoloazepinolone CID755673 that was identified through a high throughput screening campaign of 196,173 compounds. CID755673 is a pan-PKD inhibitor with submicromolar potencies. It was cell active and blocked the known biological actions of PKD and suppressed cancer-associated properties of proliferation, migration and invasion of prostate cancer cells. Importantly, this inhibitor was not competitive with ATP for enzyme inhibition and was highly selective for PKD when compared to at least 20 different kinases including CAMKII1, AKT, PKA and several PKC isoforms. Most critically, structural optimization of CID755673 has yielded a novel benzthiophene derivative kb-NB142-70 with low nanomolar potency and greater selectivity for PKD. We hypothesize that CID755673 can be optimized to a class of novel PKD inhibitors with unique mechanisms of action for potent and selective blockade of PKD functionality. Our long term goal is to establish a systemic approach to develop CID755673-derived probe molecules as innovative PKD inhibitors. Our proposed research strategies focus on lead optimization, mechanistic evaluation and in vivo efficacy assessment of CID755673 and its analogs. Three specific aims are proposed, representing the first major effort towards the development of potent and selective pharmacological ablative agents for PKD: Aim 1. Optimize CID755673 by structural modifications to access more potent and selective derivatives. Aim 2. Determine the molecular mechanisms underlying the exquisite selectivity of CID755673 and its analogs for PKD. Aim 3. Test the hypothesis that CID755673 and derivatives cause potent and selective blockade of PKD functionality in vivo.