Diverse Natural Products That Stabilize Microtubules

稳定微管的多种天然产品

• 批准号: 6750755
• 负责人: SUSAN BAND HORWITZ
• 金额: $ 37.07万
• 依托单位: ALBERT EINSTEIN COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-07-06 至 2007-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6750755
• 关键词: HeLa cells; antineoplastics; apoptosis; biological products; cell cycle; cell growth regulation; chemical structure; cytotoxicity; dosage; drug resistance; drug screening /evaluation; electron microscopy; epothilon; immunoprecipitation; microarray technology; microtubule associated protein; microtubules; multidrug resistance; neoplasm /cancer pharmacology; p53 gene /protein; paclitaxel; pharmacokinetics; phosphorylation; polymerase chain reaction; tissue /cell culture

DESCRIPTION (provided by applicant): The long-term objectives of our research are to acquire a thorough understanding of the mechanisms of action and of resistance to Taxol, an antitumor agent that is known to be efficacious in the treatment of human cancer. An intense interest in drug development is now concentrated on the epothilones and discodermolide, natural products whose chemical structures are distinct from Taxol but whose mechanisms of action and resistance have similarities, but are definitely not identical, to those of Taxol. Our plan is to dissect the similarities and differences between these three microtubule stabilizing drugs. The epothilones and/or discodermolide may have superior clinical activity compared to Taxol, particularly in tumors resistant to taxanes. An overriding theme of this grant application is the role that low doses of Taxol, the epothilones and discodermolide play in the killing of cancer cells. This emphasis on low drug dosage is a new focus for our laboratory that developed as it became clear that Taxol was responsible for cell death at low doses of drug that did not block cells in mitosis. There are undoubtedly diverse pathways by which low doses of Taxol kill cancer cells. The availability of preclinical data is essential and must contribute to the decision to move drugs into clinical trials. The specific aims of this proposal are to: 1. Determine the mechanism(s) by which cells treated with low concentrations of Taxol escape the spindle checkpoint. HeLa cells will be transfected with MAD2, a checkpoint component, to determine if its overexpression can rescue from cell death, those cells that escape from the mitotic checkpoint. The relationship between overexpression of the protein CENP-E, a component of the mitotic checkpoint, and drug resistance will also be investigated. 2. Examine the contribution of p53-dependent apoptosis to cytotoxicity caused by low concentrations of Taxol. Determine if aberrant mitosis leads to p53-dependent apoptosis. DNA microarrays will be used to survey and compare gene expression profiles of A549 cells treated with different concentrations of microtubule stabilizing drugs. 3. Investigate how the expression level and the phosphorylation status of the microtubule regulatory proteins stathmin and MAP4 in cancer cells relate to differential sensitivity to microtubule-stabilizing agents, and how these agents affect the expression profile of these proteins.

描述（由申请人提供）：我们研究的长期目标是对作用机理和对紫杉醇的抵抗的彻底理解，紫杉醇是一种抗肿瘤剂，已知在治疗人类癌症方面有效。现在，对药物开发的强烈兴趣集中在雌酮和dines固体，即化学结构与紫杉醇不同，但其作用和耐药机理的天然产物具有相似性，但绝对与紫杉醇的相似之处。我们的计划是剖析这三种微管稳定药物之间的相似性和差异。与紫杉醇相比，腹膜内甲甲酮和/或dincodermolide可能具有较高的临床活性，尤其是在抗紫杉烷的肿瘤中。该赠款应用的一个压倒性主题是低剂量的紫杉醇，雌酮酮和des固酸酯在杀死癌细胞中发挥作用的作用。对低药剂量的这种重点是我们实验室的新焦点，因为很明显，紫杉醇是导致低剂量的药物的细胞死亡，该药物没有阻止有丝分裂的细胞。毫无疑问，低剂量的紫杉醇杀死癌细胞。临床前数据的可用性至关重要，必须有助于将药物转移到临床试验中的决定。该提案的具体目的是：1。确定低浓度紫杉醇逃脱纺锤体检查点的细胞处理的机制。 HeLa细胞将用MAD2（一个检查点成分）转染，以确定其过表达是否可以从细胞死亡中挽救那些从有丝分裂检查点逃脱的细胞。还将研究蛋白质CENP-E的过表达，有丝分裂检查点的成分与耐药性之间的关系。 2。检查p53依赖性凋亡对低浓度紫杉醇引起的细胞毒性的贡献。确定异常有丝分裂是否导致p53依赖性细胞凋亡。 DNA微阵列将用于调查和比较用不同浓度的微管稳定药物处理的A549细胞的基因表达谱。 3。研究癌细胞中微管调节蛋白的表达水平和磷酸化状态如何与对微管稳定剂的差异敏感性有关，以及这些药物如何影响这些蛋白质的表达谱。