Two Photon Imaging of Drug Uptake Efflux and Modulation

药物摄取流出和调制的双光子成像

• 批准号: 6612111
• 负责人: Leonard C Erickson
• 金额: $ 29.55万
• 依托单位: INDIANA UNIV-PURDUE UNIV AT INDIANAPOLIS
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-07-01 至 2008-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6612111
• 关键词: P glycoprotein; antineoplastics; athymic mouse; bioimaging /biomedical imaging; biological transport; breast neoplasms; doxorubicin; fluorescence microscopy; membrane transport proteins; mitoxantrone; multidrug resistance; neoplasm /cancer pharmacology; neoplasm /cancer transplantation; neoplastic cell; pharmacokinetics; prostate neoplasms

Tumor resistance to chemotherapeutic agents resulting from the development of MultiDrug Resistance (MDR), remains a major cause of therapeutic failure and death. At least two proteins are well-known to play major roles in causing MDR, which is characterized by the resistance of tumor cells to a wide variety of agents of diverse structure and activity. Both proteins, P-glycoprotein (Pgp, product of the MDR1 gene) and the Multidrug resistance Related Protein (MRP, product of the MRP1 gene) are membrane transporters that produce increased drug effiux from tumor cells. Most of our understanding of the drug transporter systems comes from tissue culture studies in vitro. In the current application we propose to study the role of these transporters in drug uptake and efflux in human tumors maintained as xenografts in immuno-compromised mice. The project will test the hypotheses that overexpressing Pgp and/or MRP causes decreased drug accumulation and altered intracellular drug distribution in cancer cells and that inhibitors of Pgp and MRP reverse the action of the two transporters. Using a state-of-the-art two-photon microscope, we can study in real time how tumor cells in a living animal process anticancer drugs and respond to inhibitors of Pgp and MRP. These studies will provide direct in vivo information on the roles of Pgp and MRP in developing MDR and on the mechanisms of reversing MDR by inhibitors of Pgp and MRP in cancer cells. The proposal should lead to improved therapy for cancer patients whose tumors are resistant to anticancer agents. AIM 1 will use a two-photon microscope to clarify uptake, efflux and subcellular distribution of the highly fluorescent anticancer agents Adriamycin (ADR) and Mitoxantrone (MITOX) in human breast tumors maintained as xenografts in immuno-deficient mice. Wild type human vector only control breast tumors and tumors genetically engineered to express Pgp, MRP, or both Pgp and MRP will be studied for their ability to take up and effiux ADR and MITOX. AIM 2 will use a two-photon microscope to determine whether the inhibitors of the drug resistance transporters Pgp and MRP alter drug accumulation and retention in the wild type vector only control and resistant human breast tumors maintained as xenografts in nude nude mice. AIM 3 will use a two-photon microscope to determine the uptake and efflux of the inherently fluorescent antitumor agent MITOX in innately resistant human prostate tumors maintained as xenografts in immuno-deficient mice and will test whether modulators of Pgp and MRP reverse the resistance transporters in the prostate xenograft tumors.

肿瘤对化疗药物的耐药性是由多药耐药(MDR)引起的，仍然是治疗失败和死亡的主要原因。众所周知，至少有两种蛋白质在引起MDR中起主要作用，MDR的特征是肿瘤细胞对各种结构和活性不同的药物具有耐药性。P-糖蛋白(P-gp，mdr1基因产物)和多药耐药相关蛋白(MRP，mrp1基因产物)这两种蛋白质都是膜转运蛋白，可从肿瘤细胞产生更多的药物。我们对药物转运系统的大部分了解来自于体外组织培养研究。在目前的应用中，我们建议研究这些转运蛋白在免疫受损小鼠作为异种移植维持的人类肿瘤药物摄取和外排中的作用。该项目将测试Pgp和/或MRP过表达导致癌细胞中药物积累减少和细胞内药物分布改变的假设，以及Pgp和MRP的抑制剂逆转这两种转运蛋白的作用。 使用最先进的双光子显微镜，我们可以实时研究活动物中的肿瘤细胞如何处理抗癌药物，以及对Pgp和MRP抑制剂的反应。这些研究将为Pgp和MRP在MDR发生中的作用以及Pgp和MRP的抑制剂逆转癌细胞MDR的机制提供直接的体内信息。这项提案应该会改善那些肿瘤对抗癌药具有耐药性的癌症患者的治疗。 目的1利用双光子显微镜研究高荧光抗癌药物阿霉素(ADR)和米托蒽醌(Mitox)在免疫缺陷小鼠体内的摄取、外排和亚细胞分布。野生型人类载体只控制乳腺肿瘤和基因工程肿瘤，表达Pgp、MRP或同时表达Pgp和MRP的肿瘤将被研究其摄取和排出ADR和Mitox的能力。目的2将使用双光子显微镜来确定耐药转运蛋白PGP和MRP的抑制剂是否改变了药物在野生型载体中的累积和滞留，仅控制和耐药人乳腺肿瘤在裸鼠体内作为异种移植保持。目的3将使用双光子显微镜来检测天然荧光抗肿瘤药物Mitox在免疫缺陷小鼠体内作为异种移植的人前列腺癌的摄取和外流，并将测试Pgp和MRP的调节剂是否逆转了前列腺癌异种移植瘤中的耐药转运体。