Splicing factors as therapeutic targets for the treatment of ovarian cancer

剪接因子作为卵巢癌治疗靶点

• 批准号: 8053431
• 负责人: WILLIAM T BECK
• 金额: $ 30.4万
• 依托单位: UNIVERSITY OF ILLINOIS AT CHICAGO
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-05-01 至 2013-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8053431
• 关键词: Agar; Alternative Splicing; American; Apoptosis; Bioinformatics; CD44 gene; Cancer Etiology; Categories; Cell Cycle; Cell physiology; Cells; DNA; Defect; Diagnosis; Disease; Elements; Employee Strikes; Epithelial; Epithelial ovarian cancer; Epithelium; Eukaryota; Eukaryotic Cell; Event; Exhibits; Exons; Expressed Sequence Tags; FDA approved; Generations; Genes; Genomics; Goals; Health; Homologous Gene; Human; In Vitro; Lead; MEKs; Malignant - descriptor; Malignant Neoplasms; Malignant neoplasm of ovary; Messenger RNA; Molecular; Monitor; Mus; Mutation; Neoplasm Metastasis; Neoplastic Cell Transformation; Normal tissue morphology; Oncogenes; Outcome; Ovarian; Pattern; Pharmaceutical Preparations; Play; Polypyrimidine Tract-Binding Protein; Production; Property; Protein Isoforms; Proteomics; Public Health; RNA Splicing; RNA-Binding Proteins; Ras/Raf; Reporter; Reporting; Research; Role; SRC-associated p68 protein; Signal Pathway; Small Interfering RNA; Source; Staging; System; Testing; Therapeutic; Trans-Activators; Tumor Cell Invasion; Tumor Suppressor Genes; Validation; Variant; Woman; Work; Xenograft procedure; acrosome stabilizing factor; base; cancer therapy; cell growth; chemical synthesis; environmental change; genome-wide analysis; high throughput screening; human disease; in vivo; inhibitor/antagonist; knock-down; mRNA Precursor; malignant breast neoplasm; mouse model; neoplastic cell; new therapeutic target; novel; novel therapeutic intervention; ovarian neoplasm; overexpression; small molecule; small molecule libraries; therapeutic target; tumor; tumor growth; tumor progression; tumorigenesis

DESCRIPTION (provided by applicant): Epithelial ovarian cancer (EOC) strikes more than 25,000 American women annually, and >50% of these women will die from their disease, especially if diagnosed, as is common, with late-stage disease. To develop new therapies for this disease, it will be necessary to better understand the molecular events that are associated with the neoplastic transformation. Alternative splicing (AS), by allowing production of multiple protein isoforms from a single gene, plays a major role in expanding proteomic complexity in metazoans and adaptations to internal and external environmental changes. In general, more genes in tumors, especially those associated with tumorigenesis, exhibit alternative splice forms compared to normal tissues. There is mounting evidence that AS is associated with and possibly involved in tumor progression and/or metastasis. At present, the mechanisms leading to splicing alterations in cancer are poorly understood, but they are likely due either to mutations in cis-elements or, more likely, changes in trans-acting factors, such as splicing factors. Indeed, several splicing factors, including PTB and SRp20, are overexpressed in tumors and one, SF2/ASF, was shown to be an oncogene. PTB and SRp20 are overexpressed in human ovarian tumors, compared to normal ovarian epithelium, where PTB is either not expressed or expressed at very low levels, and expression of these SFs is associated with malignancy of these tumors. Knockdown of PTB in ovarian tumor cells in vitro by siRNA substantially suppressed tumor cell growth, colony formation, and invasiveness and led to slower tumor growth in mice bearing ovarian tumors. Our results provide proof-of-principle that splicing factors may be a class of novel and unexplored therapeutic targets for cancer treatment, at least PTB in EOC, a disease that has a dismal outcome and for which there are no good therapeutic options, especially for advanced-stage disease. In this proposal, we focus on one splicing factor, PTB, and one tumor type, EOC, and hypothesize that PTB is a druggable therapeutic target in this disease. To test our hypothesis, we propose to develop a cell- based high-throughput screen of small molecule libraries to identify small molecules that interfere with PTB activity and then study whether these identified small molecules are able to inhibit ovarian tumor growth. To this end, we offer three specific aims: (1) Develop and optimize a proprietary cell-based reporter system to monitor the activity of PTB in the cell; (2) Develop and optimize a high throughput screen (HTS) of small molecule libraries, including those containing FDA-approved small molecules as well as extracts from natural sources or compounds generated by chemical synthesis to identify PTB inhibitors; and (3) Validation of effective small molecules on ovarian tumor cell growth in vitro and in vivo. If successful, our approach will validate PTB as a novel therapeutic target and will identify a novel class of small molecule drugs based on the manipulation of alternative splicing for the treatment of ovarian cancer, and possibly other epithelial cancers. PUBLIC HEALTH RELEVANCE: Epithelial ovarian cancer (EOC) strikes more than 25,000 American women annually, and >50% of these women will die from their disease, especially if diagnosed, as is common, with late-stage disease. If successful, the research proposed here will validate targeting of splicing factors and alternative splicing as a novel therapeutic approach to the treatment of ovarian and other cancers. At the end of the project period we would have identified small molecules leading to new drugs for the treatment of these cancers, and this will clearly have a positive impact on public health.

描述（由申请人提供）：上皮卵巢癌（EOC）每年罢工超过25,000名美国妇女，其中> 50％的女性将死于其疾病，尤其是如果常见的情况，则患有晚期疾病。为了开发该疾病的新疗法，有必要更好地了解与肿瘤转化相关的分子事件。替代剪接（AS），通过允许从单个基因产生多种蛋白质同工型，在扩大后生动物的蛋白质组学复杂性以及对内部和外部环境变化的适应中起着重要作用。通常，与正常组织相比，肿瘤中更多的基因，尤其是与肿瘤发生相关的基因表现出替代的剪接形式。有越来越多的证据表明，与肿瘤进展和/或转移有关并可能涉及并可能参与。目前，导致癌症剪接改变的机制知之甚少，但它们可能是由于顺式元素的突变，或者更有可能发生的反式作用因子的变化，例如剪接因子。实际上，包括PTB和SRP20在内的几个剪接因子在肿瘤中过表达，一个SF2/ASF被证明是癌基因。与正常的卵巢上皮相比，PTB和SRP20在人类卵巢肿瘤中过表达，那里的PTB不能以非常低的水平表达或表达，并且这些SF的表达与这些肿瘤的恶性肿瘤有关。 siRNA在体外敲低卵巢肿瘤细胞中的PTB实质上抑制了肿瘤细胞的生长，菌落形成和侵袭性，并导致患有卵巢肿瘤的小鼠的肿瘤生长缓慢。我们的结果提供了原则上的证明，即剪接因子可能是一类新颖且未开发的癌症治疗靶标，至少是EOC中的PTB，EOC中的疾病具有令人沮丧的结果，并且没有良好的治疗选择，尤其是对于晚期疾病。在此提案中，我们专注于一种剪接因子，PTB和一种肿瘤类型，EOC，并假设PTB是该疾病中的可药治疗靶标。为了检验我们的假设，我们建议开发一个基于细胞的小分子文库的高通量屏幕，以鉴定干扰PTB活性的小分子，然后研究这些鉴定出的小分子是否能够抑制卵巢肿瘤的生长。为此，我们提供了三个具体目标：（1）开发和优化一个基于细胞的记者系统以监视PTB在细胞中的活性； （2）开发并优化了小分子文库的高吞吐量筛选（HTS），包括包含FDA批准的小分子的筛选，以及来自化学合成产生的自然源或化合物的提取物，以鉴定PTB抑制剂； （3）在体外和体内验证有效的小分子对卵巢肿瘤细胞生长的验证。如果成功，我们的方法将验证PTB作为一种新型的治疗靶标，并基于操纵替代剪接治疗卵巢癌的替代剪接，以及可能其他上皮癌的新型小分子药物。公共卫生相关性：上皮卵巢癌（EOC）每年罢工超过25,000名美国妇女，其中> 50％的女性将死于其疾病，尤其是如果被诊断为常见，患有晚期疾病。如果成功的话，这里提出的研究将验证靶向剪接因子和替代剪接作为一种新型治疗卵巢和其他癌症的治疗方法。在项目期结束时，我们将确定小分子，导致新药治疗这些癌症，这显然将对公共卫生产生积极影响。