Combinatorial Selection of Beta-Catenin/T Cell Factor Pathway Inhibitors

描述（由申请人提供）：结直肠癌（CRC）是美国癌症死亡的第二大原因，在早期发现时是可以预防和治愈的。虽然几种化学预防剂在实验动物模型中预防CRC，但没有一种药物被批准用于人类。除了手术切除，这是很少治愈晚期疾病，目前的治疗结肠癌依赖于传统的细胞毒性药物，效果有限。我们的长期目标是开发修饰的寡核苷酸（ODNs），为癌症（特别是CRC）的治疗提供创新的治疗产品。致癌β-连环蛋白和T细胞因子（TCF）之间转录复合物的形成被认为是CRC细胞发育中的关键事件。调节该途径和/或破坏β-连环蛋白和TCF相互作用的药物可能抑制导致CRC的许多靶基因的后续表达。本项目的目标是鉴定一种紧密结合和高度特异性的ODN，其将结合人TCF 4的β-catenin结合结构域（TCF-CBD）以阻断β-catenin与TCF的结合和/或破坏β-catenin与TCF的相互作用。基于结构的设计和新颖的组合选择将用于实现这一目标。将追求三个具体目标：目的（1）表达、纯化和表征TCF-CBD蛋白;目的（2）鉴定靶向TCF-CBD的含有5-氨基烯丙基-2 '-脱氧尿苷（5-AA-适体）的紧密结合和高度特异性的适体;目的（3）测试5-AA-适体在体外对β-连环蛋白TCF复合物的破坏。这些实验最终将引入新的抗CRC化合物。这些先导化合物将在细胞培养和动物模型中进行测试。我们新的抗癌发现和开发策略可以应用于其他癌症。此外，这项研究的结果将用于申请未来的NIH RO 1资助。摘要：抗癌药物的开发已被证明是具有挑战性的。然而，基于寡核苷酸的抑制药物可以根据其结合特定蛋白质的能力从非常大的随机库（10[12]约10[14]个成员）中选择。这种新的抗癌策略很重要，因为它可以让我们非常迅速地发现高效的药物化合物。

DESCRIPTION (provided by applicant): Colorectal cancer (CRC), the second leading cause of cancer mortality in the United States, is preventable and curable when found in its early stages. Although several chemopreventive agents prevent CRC in experimental animal models, no agent has been approved for human use. Besides surgical resection, which is rarely curative in advanced disease, current therapy for colon cancer relies on traditional cytotoxic agents with limited effects. Our long-term goal is to develop modified oligonucleotides (ODNs) to provide innovative therapeutic products for the treatment of cancer, in particular CRC. The formation of a transcriptional complex between an oncogenic beta-catenin and a T cell factor (TCF) is believed to be a key event in CRC cell development. Agents that modulate this pathway and/or disrupt the beta-catenin and TCF interaction are likely to inhibit the subsequent expression of many target genes that leads to CRC. The goal of this project is to identify a tight-binding and highly specific ODN that will bind to the beta-catenin binding domain of human TCF4 (TCF-CBD) to block the beta-catenin binding with TCF and/or disrupt the beta-catenin and TCF interaction. Structure-based design and novel combinatorial selection will be used to achieve this goal. Three specific aims will be pursued: Aim (1) express, purify, and characterize the TCF-CBD protein; Aim (2) identify tightly binding and highly specific aptamers containing 5-aminoallyl-2'-deoxyuridine (5-AA-aptamers) targeting TCF-CBD; Aim (3) test the 5-AA-aptamers for disruption of the beta-catenin.TCF complex in vitro. These experiments should ultimately introduce new lead anti-CRC compounds. Such lead compounds will be tested in cell cultures and animal models. Our novel anticancer discovery and development strategy can be applied to other cancers. In addition, the results generated from this research will be used in an application for a future NIH RO1 grant. Lay abstract: Development of anticancer drugs has proven to be challenging. However, oligonucleotide- based inhibition drugs can be selected from a very large random pool (10[12] approximately 10[14] members) by their ability to bind a specific protein. This novel anticancer strategy is important because it should allow us to very rapidly discover highly effective drug compounds.