Structural and functional analysis of a novel class of androgen receptor antagonists

项目摘要 一类新型雄激素受体拮抗剂的结构和功能分析 雄激素剥夺疗法(ADT)和雄激素受体(AR)靶向药物是 转移性前列腺癌(PCA)治疗。然而，ADT和/或AR靶向剂上的PCA通常会导致 复发和抗去势前列腺癌(CRPC)，其主要由AR激活在 阉割条件。下一代AR靶向药物如苯扎鲁胺和阿比特龙可以抑制 但平均仅延长CRPC患者的生存期约4~5个月。少校 抵抗下一代AR靶向药物的机制是AR的重新激活。小说 阻止对当前AR靶向治疗的耐药性的发展的策略是迫切需要和 主要的药物开发挑战。现有FDA批准的AR拮抗剂与双氢睾酮竞争 (DHT)与AR的配体结合结构域(LBD)结合，患者最终对 这些治疗。克服耐药性的一种方法是开发抑制AR的化合物 另一种方式。我们已经确定了一种小分子，SID 3712502，它能够抑制AR缺乏 LBD。为了优化这种新型抑制剂的疗效，我们开发了结构类似物并鉴定了 (+)-JJ-74-138作为有希望的候选人。我们的初步数据表明，(+)-JJ-74-138是一种新的AR 在培养和体内均能降解核AR并抑制对苯扎鲁胺抗性的CRPC的拮抗剂 异种移植瘤。然而，目前尚不清楚AR与(+)-JJ-74-138如何相互作用，这使得很难 理性地开发更有效的类似物。我们提出以下两个具体目标来定义(+)-JJ-74- 138及其母体化合物SID 3712502与AR结合并开发具有改进效力的新类似物， 抑制和降解核AR的水的溶解性和专一性。目标1将决定如何 用低温电子显微镜观察SID-3712502支架与AR的结合。我们将提纯全长AR (Ar-FL)，用于低温EM结构分析的AR-FL与SID 3712502和(+)-JJ-74-138的相互作用 用单粒子方法合成了AR-Fl2/R1881/Are/SID 3712502(或(+)-JJ-74-138)的合适络合物。 目标2将设计、合成和分析(+)-JJ-74-138的类似物，目标是鉴定小分子 具有亚微摩尔效力，改善的水溶解性，以及对AR阳性细胞的高特异性。我们会 在反复的物理化学改进中系统地准备先导化合物(S)的类似物 以及基于体外和基于细胞的分析的构效关系(SAR)分析的优化。 该项目的成功将极大地促进这类新型AR拮抗剂的开发 CRPC的治疗，包括对苯扎鲁胺耐药的CRPC。

Project Summary Title: Structural and functional analysis of a novel class of androgen receptor antagonists Androgen deprivation therapy (ADT) and androgen receptor (AR)-targeting agents are the mainstay of metastatic prostate cancer (PCa) treatment. However, PCa on ADT and/or AR-targeting agents usually lead to relapse and castration-resistant prostate cancer (CRPC), which is mainly driven by AR activation under castration conditions. Next-generation AR-targeting agents such as enzalutamide and abiraterone can inhibit AR in CRPC but prolong the survival of CRPC patients for only about 4-5 months on average. The major mechanism responsible for the resistance to next-generation AR-targeting agents is reactivation of AR. Novel strategies to block the development of resistance to the current AR-targeted therapy are an urgent need and a major drug development challenge. Existing FDA-approved AR antagonists compete with dihydrotestosterone (DHT) for binding to the ligand binding domain (LBD) of AR, and patients eventually develop resistance to these treatments. One approach to overcoming resistance is to develop compounds that inhibit AR in alternative ways. We have identified a small molecule, SID 3712502, that is capable of inhibiting AR lacking LBD. To optimize the efficacy of this new class of inhibitors, we developed structural analogues and identified (+)-JJ-74-138 as a promising candidate. Our preliminary data suggest that (+)-JJ-74-138 is a novel AR antagonist capable of degrading nuclear AR and inhibiting enzalutamide-resistant CRPC both in culture and in xenograft tumors. However, it is not yet clear how AR interacts with (+)-JJ-74-138, which makes it difficult to rationally develop more potent analogues. We propose the following 2 specific aims to define how (+)-JJ-74- 138 and its parent compound SID 3712502 bind to AR and develop new analogs with improved potency, aqueous solubility and specificity for inhibition and degradation of nuclear AR. Aim 1 will determine how the SID 3712502 scaffold binds to AR using cryogenic electron microscopy (cryoEM). We will purify full-length AR (AR-FL), characterize interactions of AR-FL with SID 3712502 and (+)-JJ-74-138 for cryoEM structural analysis of a suitable complex of AR-FL2/R1881/ARE/SID 3712502 (or (+)-JJ-74-138) using single particle methods. Aim 2 will design, synthesize and analyze analogues of (+)-JJ-74-138, with the goal to identify small molecules with submicromolar potency, improved aqueous solubility, and high specificity for AR-positive cells. We will systematically prepare analogs of the lead compound(s) in iterative rounds of physicochemical improvements and optimizations based on structure–activity relationship (SAR) analyses from in vitro and cell-based assays. The success of this project will greatly facilitate the development of this class of novel AR antagonists for the treatment of CRPC, including enzalutamide-resistant CRPC.