Heat Shock Protein Function for Drug Discovery

描述（由申请人提供）： 控制肿瘤细胞生长和存活的信号转导途径 为开发新的抗癌药物提供了一个有吸引力的、合理的靶点， 剂. 一种特别有效的调节这些途径的方法可以 由改变热休克蛋白（Hsp）功能的药物提供 例如Hsp 90，而不是任何特定信号分子。 这些 普遍表达的分子伴侣在癌症中不突变。 相反，它们似乎在促进或促成 肿瘤转化通过增强多个的稳定性和活性， 致癌生长因子受体、激酶和转录因子。 超过 在过去的5年中，已经鉴定出几种小分子天然产物， 作为与Hsp或其辅助分子伴侣相互作用的潜在抗癌剂。 这些药物之一，17 -N-烯丙基氨基-17-去甲氧基格尔德霉素（17 MG）， 进入I期临床试验，但17 MG和其他类别的 迄今发现的hsp结合药物在其生物学活性方面存在严重的局限性。 临床应用，包括溶解性、代谢、效力差等问题 和/或有限的特异性。 为了达到将热休克蛋白作为一种新的 癌症化学治疗靶点，需要找到具有 从而调节它们在体内复杂的细胞功能。 最近，一种用于表征和筛选生物活性物质的专有技术 化合物已经由TELIK，Inc.它依赖于 根据化合物的结合特性 （“指纹”）对一组蛋白质。 与传统的高 通量方法，这种靶相关亲和力分析（TRAP）方法 允许筛选相对少量的纯化合物， 大约200-400个，以识别针对特定 分子靶点或细胞途径。 我们假设TRAP的应用 将技术应用于由报告者构建的屏幕生成的数据， 鉴定具有临床应用潜力的新的HSP结合化合物， 发展 为了验证这一假设，我们组织了一个多学科的 拥有完成 具体目标如下： 1)为了使用两个阶段鉴定改变Hsp功能的有效化合物， 一系列中等通量、基于细胞的报告基因测定和TRAP技术。 2)通过以下方法确定最有前途的化合物以供进一步开发： 对增殖、细胞周期进程、凋亡和细胞周期的定量影响 特异性分子靶点如erbB 2、Akt、突变型p53和 类固醇激素受体 3)评价新型热休克活性化合物的潜在相互作用 使用固相药物固定化的特异性Hsp和辅助分子伴侣 技术. 在实践层面上，这些探索性研究将提供新的HSP活性 可用于进一步验证Hsp作为治疗靶点的试剂 干预 我们确定的代理人也可以作为起点， 在开发具有独特功能的有用抗癌药物方面的领先优化 行动机制。 在基本的科学水平上，我们的应用程序构成了 一种创新的药理学方法来定义机制， 分子伴侣如Hsp 90促进肿瘤发生。 因此， 在这个项目中获得的成果可能会对 更有效地预防和治疗癌症。

DESCRIPTION (provided by applicant): The signal transduction pathways that control tumor cell growth and survival provide an attractive, rational target for the development of new anticancer agents. A particularly effective approach to modulating these pathways could be provided by drugs which alter the function of heat shock proteins (Hsp) such as Hsp90 instead of anyone specific signaling molecule. These ubiquitously expressed molecular chaperones are not mutated in cancer. Instead, they appear to play an essential role in facilitating or enabling neoplastic transformation by enhancing the stability and activity of multiple oncogenic growth factor receptors, kinases and transcription factors. Over the past 5 years, several small molecule natural products have been identified as potential anticancer agents that interact with Hsp or their co-chaperones. One of these agents, 17 -N-allylamino-17 -demethoxygeldanamycin ( 17 MG ) has entered phase I clinical trials, but both 17 MG, and the other classes of Hsp-binding drugs identified so far suffer from serious limitations to their clinical utility including problems with solubility, metabolism, poor potency and/or limited specificity. To achieve the goal of exploiting Hsp as novel cancer chemotherapeutic targets, a need exists to find additional agents with which to modulate their complex cellular functions in vivo. Recently, a proprietary technology for characterizing and screening bioactive compounds has been developed by TELIK, Inc. that relies on the classification of a vast library of compounds according to their binding characteristics ("fingerprints") against a panel of proteins. In contrast to traditional high throughput methods, this Target-Related Affinity Profiling (TRAP) approach allows the screening of a relatively small number of pure compounds, approximately 200-400, to identify active molecules against a specific molecular target or cellular pathway. We hypothesize that application of TRAP technology to data generated by reporter construct-based screens will allow us to identify new Hsp-binding compounds with the potential for clinical development. To test this hypothesis, we have assembled a multidisciplinary team with the expertise and infrastructure required to accomplish the following specific aims: 1) To identify potent compounds that alter Hsp function using a two stage series of moderate throughput, cell-based reporter assays and TRAP technology. 2) To identify the most promising compounds for further development by quantitating effects on proliferation, cell cycle progression, apoptosis and alterations in specific molecular targets such as erbB2, Akt, mutant p53 and steroid hormone receptors. 3) To evaluate the potential interaction of novel heat shock-active compounds with specific Hsp and co-chaperones using solid phase drug immobilization techniques. At a practical level these exploratory studies will provide new Hsp-active agents that can be used to further validate Hsp as targets for therapeutic intervention. The agents we identify can also serve as starting points for lead optimization in the development of useful anticancer agents with unique mechanisms of action. At a basic scientific level our application constitutes an innovative pharmacological approach to defining the mechanisms by which chaperones such as Hsp90 facilitate oncogenesis. Consequently, the insights gained in this project are likely to have significant implications for the more effective prevention and cure of cancer.