Targeting multiple signaling steps to achieve synergy

7.摘要 发展中的癌症治疗领域正处于一个令人兴奋的关头。在这方面的主要进展 了解导致癌症进展和化疗耐药的分子缺陷，以及 可用的分子靶向药物急剧增加，提供了前所未有的发展机遇 潜在有用的联合疗法。FDA最近的决定进一步促进了科学追求 允许对涉及一种以上未经批准的药物的组合进行临床测试。 新的药物针对控制基因表达的信号通路中的步骤，包括抑制剂 生长因子与其受体和酪氨酸激酶抑制剂等抑制剂的结合。越多 最近RNAi试剂的引入为后基因沉默提供了更多的机会。 转录水平。这个项目的目标是发展概念(数学框架)和方法 用于组合调节信号级联中不同步骤的代理，目标是实现真的 协同作用或临床协同作用。我们提出了三个目标，以Wnt/？-catenin/Survivin信号转导为模型 路径。该通路在肿瘤的发生和化疗耐药中起着多种重要作用。 第一个目标是建立药物组合的交互药效学模型 以转录前和转录后信号事件为目标。这些模型与单剂PD一起使用 参数值(斜率、Emax、EC50，选自文献值和目标3中的实验数据)至 模拟不同组合的结果。In silo结果用在 目的2在目标3中确定用于实验验证的协同、添加或拮抗组合。 第二个目标是开发一种方法，用统计上的确定性来量化相互作用 在量效曲线平行或非平行的药物中。第三个目标是获得 模型预测的实验验证。第一个目标是在培养细胞中获得PD参数 针对Wnt/？-catenin/Survivin转录前和转录后几个步骤的单一药物的价值 信号传递(例如，抗Frizzed抗体、siRNAs(抗Dheveled、PP2A、Survivin)和小分子 药物OHL(被发现减少-连环蛋白/Survivin信号转导)。效应器包括野生型Survivin MRNA和蛋白质水平、总和活性非磷酸化连接素水平以及Tcf/Lef 转录活性。第二个目标是评估模型预测的交互是否在 体外和体内。 潜在收益是三倍。首先，结果将有助于组合目标的开发 信号通路中的多个步骤。第二，鉴于Wnt/？-catenin/Survivin的关键作用 作为肿瘤发展的信号，这些结果将进一步深入了解其对治疗收益的调节。 第三，克服Survivin介导的化疗耐药，这是治疗失败的主要原因，这将有所改善 化疗的疗效。

7. Abstract The field of developmental cancer therapeutics is at an exciting juncture. The major advances in the understanding of molecular defects leading to cancer progression and chemoresistance, together with the dramatic increase in the available molecular targeting drugs, provide unprecedented opportunities to develop potentially useful combination therapies. The scientific pursuit is further aided by the recent FDA decision to allow clinical testing of combinations involving more than one unapproved drugs. The newer agents target steps in signaling pathways that control gene expression, including inhibitors of binding of growth factors to their receptors and inhibitors of such as tyrosine kinase inhibitors. The more recent introduction of RNAi agents provides additional opportunity for gene silencing on the post- transcriptional level. The goal of this project is to develop the concept (mathematical framework) and methods for combining agents that modulate different steps in a signaling cascade, with the goal of achieving true synergy or clinical synergy. We propose three aims, using Wnt/¿-catenin/survivin signaling as the model pathway. This pathway plays multiple important roles in cancer development and chemoresistance. The first aim is to establish interactive pharmacodynamic models (IPM) on combinations of agents targeting pre- and the post-transcriptional signaling events. These models are used with the single agent PD parameter values (slope, Emax, EC50, selected from literature values and from experimental data in Aim 3) to simulate the results of different combinations. The in silico results are analyzed with the method developed in Aim 2 to identify synergistic, additive or antagonistic combinations for experimental validation in Aim 3. The second aim is to develop a method that quantifies, with statistical certainty, the interactivity among drugs with parallel or non-parallel concentration-effect curves. The third aim is to obtain experimental validation of model predictions. The first objective is obtain in cultured cells the PD parameter values for single agents directed at several pre- and post-transcriptional steps in Wnt/¿-catenin/survivin signaling (e.g., antibody against Frizzled, siRNAs (against Disheveled, PP2A, survivin), and a small molecule drug OHL (which was found to reduce ¿-catenin/survivin signaling). The effectors include wild type survivin mRNA and protein levels, levels of total and the active non-phosphorylated ¿-catenin, and Tcf/Lef transcriptional activity. The second objective is to evaluate if the model-predicted interactivity is achieved in vitro and in vivo. Potential gains are three-fold. First, the results will assist the development of combinations targeting multiple steps in a signaling pathway. Second, in view of the critical roles of the Wnt/¿-catenin/survivin signaling in tumor development, the results will further yield insights on its modulations for therapeutic gains. Third, overcoming the survivin-mediated chemoresistance, a major cause of treatment failures, will improve the efficacy of chemotherapy.