Regulation and Function of the p14ARF/topoisomerase I Complex in Cancer

p14ARF/拓扑异构酶 I 复合物在癌症中的调节和功能

• 批准号: 7813636
• 负责人: RUTH A GJERSET
• 金额: $ 31.32万
• 依托单位: TORREY PINES INST FOR MOLECULAR STUDIES
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-30 至 2012-09-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7813636
• 关键词: Affect; Antibodies; Biochemical; Biological; Biological Assay; C-terminal; CDKN2A gene; Camptothecin; Cancer cell line; Cell Culture Techniques; Cell Line; Cells; Chromatin; Clinic; Clinical; Coenzyme A; Complex; DNA; DNA Binding; DNA Double Strand Break; Defect; Diagnostic; Double Strand Break Repair; Down-Regulation; Drug Delivery Systems; Event; Freezing; Frequencies; Funding; Goals; Grant; Histone Acetylation; Human; Immunofluorescence Immunologic; Immunoprecipitation; In Vitro; Lead; Malignant Neoplasms; Maps; Mediating; Modeling; Molecular; Molecular Biology Techniques; Mutation; Nonhomologous DNA End Joining; Nude Mice; Outcome; Pathway interactions; Pensions; Pharmaceutical Preparations; Phosphorylation; Phosphorylation Site; Play; Protein Kinase C; Proteins; Recovery; Regulation; Resistance; Role; Serine; Small Interfering RNA; Specificity; Specimen; Spermidine; Surrogate Markers; TP53 gene; Therapeutic; Treatment Protocols; Tumor Suppressor Proteins; Type I DNA Topoisomerases; United States National Institutes of Health; base; cancer cell; cancer therapy; casein kinase II; chemotherapeutic agent; chemotherapy; histone acetyltransferase; human TOP1 protein; improved; in vitro Assay; in vivo; inhibitor/antagonist; insight; neoplastic cell; novel; novel strategies; novel therapeutics; overexpression; parent grant; preclinical evaluation; public health relevance; repaired; research study; response; subcutaneous; tool; tumor

DESCRIPTION (provided by applicant): This application responds to Notice Number (NOT-OD-09-058) entitled: NIH Announces the Availability of Recovery Act Funds for Competitive Revision Applications. The long term goal of this study is to develop improved cancer treatments through modulation of topoisomerase I (topo I), an important target for camptothecin-like chemotherapeutic drugs, and to further elucidate how the p14ARF/topo I complex contributes to the mechanism of cancer and to the therapy response. p14ARF plays a well-established role in the p53 pathway, and also engages in a novel p53-independent interaction with topo I. The interaction requires topo I serine phosphorylation, activates topo I, and enhances cellular sensitivity to camptothecin and related topo I-targeted chemotherapeutic drugs. Cancer cells with reduced topo I phosphorylation lack p14ARF/topo I complexes and are resistant to camptothecin. A better understanding of the regulation of this complex would therefore elucidate the roles of both proteins in cancer, and could lead to improved diagnostic and therapeutic strategies for cancer. The Specific Aims of the parent grant are to (1) Determine the molecular features of the p14ARF/topo I interaction, (2) Define the molecular mechanism of p14ARF-mediated activation of topo I, (3) Determine how frequently abnormalities in p14ARF/topo I complex formation occur in cancer and whether they correlate statistically with clinic attributes of tumors, and (4) Determine the therapeutic potential of p14ARF-mediated therapy sensitization. The revised grant introduces an additional Aim (5) that studies the effects of Spermidine-CoA-based inhibitors of histone acetylation, a class of cancer cell-targeted compounds that inhibit double strand break repair and sensitize cells to camptothecin. The Aim examines how these inhibitors affect topo I alone and in combination with p14ARF and provides a preclinical evaluation of their efficacy as therapy sensitizers in the presence and absence of ARF. The study will employs molecular biology techniques (Aim I), biochemical assays (Aims II and V), immunoprecipitation/western analysis and immunofluorescence (Aim III), and cell culture-based viability assays and human tumor xenograph models in nude mice (Aims IV and V). PUBLIC HEALTH RELEVANCE: This study develops novel approaches based on the p14ARF tumor suppressor and Spermidine-CoA-based inhibitors of histone acetylation to improve cellular responses to topoisomerase I-targeted chemotherapies and reverse therapy resistance, a major obstacle to successful cancer treatment. The study also develops diagnostic tools for identifying therapy responsive tumors and optimizing therapeutic regimens. .

描述(由申请人提供)：本申请响应通知编号(NOT-OD-09-058)，标题为：NIH宣布恢复法案资金可用于竞争性修订申请。这项研究的长期目标是通过调节拓扑异构酶I(Topo I)来开发改进的癌症治疗方法，Topo I是喜树碱类化疗药物的重要靶点，并进一步阐明p14ARF/Topo I复合体如何在癌症机制和治疗反应中发挥作用。P14ARF在P53途径中发挥重要作用，并与Topo I参与一种新的P53非依赖的相互作用。这种相互作用需要Topo I丝氨酸磷酸化，激活Topo I，并增强细胞对喜树碱和相关Topo I靶向化疗药物的敏感性。Topo I磷酸化降低的癌细胞缺乏p14ARF/topo I复合体，并且对喜树碱具有耐药性。因此，更好地了解这种复合体的调节将阐明这两种蛋白质在癌症中的作用，并可能导致改进癌症的诊断和治疗策略。母基金的具体目的是(1)确定p14ARF/topo I相互作用的分子特征，(2)确定p14ARF介导的topo I激活的分子机制，(3)确定癌症中p14ARF/topo I复合体形成的异常频率，以及它们是否与肿瘤的临床属性统计相关，以及(4)确定p14ARF介导的治疗增敏的治疗潜力。修订后的拨款引入了一个额外的目标(5)，研究基于亚精胺-辅酶A的组蛋白乙酰化抑制剂的效果，组蛋白乙酰化是一种针对癌细胞的化合物，可以抑制双链断裂修复并使细胞对喜树碱敏感。目的是研究这些抑制剂如何单独以及与p14ARF联合影响Topo I，并在存在和不存在ARF的情况下对它们作为治疗增敏剂的疗效进行临床前评估。这项研究将使用分子生物学技术(AIM I)、生化分析(AIMS II和V)、免疫沉淀/蛋白质分析和免疫荧光(AIM III)，以及基于细胞培养的活性分析和裸鼠体内人类肿瘤移植模型(AIMS IV和V)。 公共卫生相关性：这项研究开发了基于p14ARF肿瘤抑制因子和基于亚精胺-辅酶A的组蛋白乙酰化抑制剂的新方法，以改善细胞对拓扑异构酶I靶向化疗的反应和逆转治疗耐药性，这是成功治疗癌症的主要障碍。这项研究还开发了诊断工具，用于识别治疗敏感型肿瘤和优化治疗方案。 。