HER-2/IGF-IR cross-talk and Herceptin resistance

HER-2/IGF-IR 串扰和赫赛汀耐药

• 批准号: 7016461
• 负责人: RITA NAHTA
• 金额: $ 2.88万
• 依托单位: UNIVERSITY OF TX MD ANDERSON CAN CTR
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-08-01 至 2007-02-15
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7016461
• 关键词: breast neoplasms; model; nanotechnology

DESCRIPTION (provided by applicant): Dr. Rita Nahta's career goal is to become an independent researcher focused on the molecular mechanisms of drug resistance in breast cancer with a specific interest in targeted therapeutics and growth factor receptors. This K01 Award will assist her transition to a fully independent scientific investigator. The next year or two will be critical for polishing her molecular biology skills and developing new skills in the areas of nanotechnology and animal models under the mentorship of Drs. Francisco J. Esteva and Mien-Chie Hung. The M. D. Anderson Cancer Center offers an excellent collaborative environment for implementation of the proposed research plan. Drs. Esteva and Hung are highly regarded among the scientific community, and Dr. Nahta will benefit from their combined expertise in the areas of signal transduction, drug resistance, molecular therapeutics, cell cycle regulation and translational research. The Breast Cancer Translational Research Laboratory, which is directed by Dr. Esteva, is an integral component of the Breast Cancer Research Program directed by Dr. Hung. The stimulating intellectual and scientific environment of this program will greatly enhance Dr. Nahta's career development. Dr. Nahta's current research focus is on the molecular mechanisms of resistance to the HER-2-targeted antibody Herceptin. Using an in vitro model of Herceptin resistance that she developed, she observed the following: 1) HER-2 forms a unique heterodimer with IGF-IR in resistant cells. HER-2 in this complex is phosphorylated, suggesting cross-talk from IGF-IR to HER-2; 2) p27kip1, which lies downstream of both HER-2 and IGF-IR, is downregulated in resistant cells. Ectopic expression of p27kip1 restores Herceptin sensitivity. Based on these findings, the central hypothesis of this application is that Herceptin resistance is mediated by increased binding of HER-2 to IGFIR with subsequent degradation of p27kip1 in breast cancer cells. Our specific aims are to: 1) Characterize the interaction between HER-2 and IGF-IR; 2) Define the molecular mechanism by which HER-2/IGF-IR downregulates p27kip1; 3) Investigate HER-2/IGF-IR as a therapeutic target in vivo. We will use GST pulldown assays, nanotechnology, protein assays, PCR, siRNAtransfection, and in vivo mouse studies. Our studies will ultimately allow the identification of tumors most likely to respond to Herceptin, and will guide the development of more effective targeted therapies for HER-2-overexpressing breast cancer.

描述（由申请人提供）：Rita Nahta博士的职业目标是成为一名独立研究人员，专注于乳腺癌耐药的分子机制，对靶向治疗和生长因子受体特别感兴趣。这个K 01奖将帮助她过渡到一个完全独立的科学研究者。接下来的一两年将是至关重要的抛光她的分子生物学技能和发展新的技能，在纳米技术和动物模型的指导下，博士弗朗西斯科J. Esteva和Mien-Chie洪。分枝D.安德森癌症中心为实施拟议的研究计划提供了良好的协作环境。Esteva博士和Hung博士在科学界备受推崇，Nahta博士将受益于他们在信号转导、耐药性、分子治疗、细胞周期调控和转化研究领域的综合专业知识。乳腺癌转化研究实验室由Esteva博士领导，是Hung博士领导的乳腺癌研究计划的组成部分。该计划的激励智力和科学环境将极大地促进Nahta博士的职业发展。Nahta博士目前的研究重点是对HER-2靶向抗体赫赛汀耐药的分子机制。使用她开发的赫赛汀抗性的体外模型，她观察到以下结果：1）HER-2在抗性细胞中与IGF-IR形成独特的异源二聚体。该复合物中的HER-2被磷酸化，表明IGF-IR与HER-2的串扰; 2）位于HER-2和IGF-IR下游的p27 kip 1在抗性细胞中下调。异位表达p27 kip 1可恢复赫赛汀敏感性。基于这些发现，本申请的中心假设是赫赛汀抗性是由乳腺癌细胞中HER-2与IGFIR的结合增加以及随后的p27 kip 1降解介导的。我们的具体目标是：1）研究HER-2与IGF-IR之间的相互作用; 2）明确HER-2/IGF-IR下调p27 kip 1的分子机制; 3）研究HER-2/IGF-IR作为体内治疗靶点的作用。我们将使用GST下拉分析，纳米技术，蛋白质分析，PCR，siRNA转染和小鼠体内研究。我们的研究将最终允许识别最有可能对赫赛汀产生反应的肿瘤，并将指导开发更有效的HER-2过表达乳腺癌靶向治疗。