Nucleolin--A Novel Target for Cancer Drug Discovery

描述：（申请人提供） 本申请的目标是验证核仁素作为一种新的靶点， 癌症的治疗干预。核仁素的鉴定 一个分子靶点是由于发现了非反义富含G 寡核苷酸（GRO），其对抗肿瘤细胞具有显著的生长抑制作用， 许多实体瘤和白血病细胞系。有广泛的相关性 GRO的抗增殖活性和它们结合 到核仁素蛋白。核仁素是一种多功能的核仁蛋白 关键参与细胞生长，也存在于细胞表面。 已知核仁素水平在恶性细胞中升高， 正常细胞，初步数据表明，针对 核仁素将是肿瘤选择性的。尽管GRO本身 尽管有相当大的治疗潜力，但寡核苷酸的递送仍然是一个挑战。 其临床应用的主要障碍，以及替代品的开发 核仁素抑制剂是理想的。调查人员已经开发出 可用于鉴定小分子或肽的筛选测定 从化合物库中获得核仁素抑制剂。核仁素也可以 合理的药物设计方法，由于结构的可用性， 类似蛋白质的信息。在如此广泛的发展研究能够 开始，有必要进一步验证核仁素作为一种新的靶点 用于药物发现。因此，本建议的总体目标是 证明核仁素表达或功能的调节导致肿瘤- 选择性抑制细胞生长。为此，具有以下特征的细胞系 将产生核仁素可诱导下调或过表达， 表征了反义寡核苷酸也将用于靶向 抑制核仁素表达。为了评估肿瘤选择性， 细胞增殖率、核仁素水平和 对GRO的敏感性将进一步探讨。此外，该机制由 将通过确定核仁素介导的生长抑制来检查 使用分子技术和蛋白质组学研究GRO诱导的核仁素变化。 预计蛋白质组学实验，以检测蛋白质的变化， 在GRO处理的细胞中的表达也将阐明GRO的新机制 影响，并可能确定其他蛋白质靶点， 细胞生长停滞。

DESCRIPTION: (provided by applicant) The goal of this application is to validate nucleolin as a novel target for therapeutic intervention in cancer. The identification of nucleolin as a molecular target has resulted from the discovery of non-antisense G-rich oligonucleotides (GROs) that have profound growth inhibitory effects against many solid tumor and leukemia cell lines. There is an extensive correlation between the antiproliferative activity of the GROs and their ability to bind to nucleolin protein. Nucleolin is a multifunctional nucleolar protein critically involved in cell growth, and also present on the cell surface. Levels of nucleolin are known to be elevated in malignant cells compared to normal cells, and preliminary data indicate that strategies to target nucleolin will be tumor-selective. Although the GROs themselves have considerable therapeutic potential, delivery of oligonucleotides remains a major obstacle to their clinical use, and the development of alternative nucleolin inhibitors is desirable. The investigators have already developed screening assays that can be used to identify small molecule or peptide inhibitors of nucleolin from compound libraries. Nucleolin is also accessible to rational drug design methods, due to the availability of structural information on similar proteins. Before such extensive development studies can begin, it will be necessary to further validate nucleolin as a novel target for drug discovery. The overall aim of this proposal is therefore to demonstrate that modulation of nucleolin expression or function causes tumor- selective inhibition of cell growth. To this end, cell lines that have inducible down-regulation or overexpression of nucleolin will be developed and characterized. Antisense oligonucleotides will also be used to target inhibition of nucleolin expression. To evaluate tumor-selectivity, the relationship between cell proliferation rate, levels of nucleolin, and sensitivity to GROs, will be further explored. In addition, the mechanism by which nucleolin mediates growth inhibition will be examined by determining GRO-induced changes in nucleolin, using molecular techniques and proteomics. It is anticipated that proteomics experiments to detect changes in protein expression in GRO-treated cells will also elucidate the novel mechanism of GRO effects and will potentially identify other protein targets that participate in cell growth arrest.