DEFINING THE CELLULAR AND PHYSIOLOGICAL ROLE OF ABCA2

描述（由申请人提供）：ATP结合盒（ABC）转运蛋白ABCA 2的过表达与雌莫司汀（一种用于治疗难治性前列腺癌的药物）的耐药性有关。ABCA 2在将胆固醇、类固醇和脂质运输到内溶酶体中中具有推定的作用，表明在人类疾病（包括癌症和动脉粥样硬化）中具有作用。迄今为止，ABCA 2在细胞系中的强制过表达一直是用于研究其功能的唯一工具。本提案中概述的研究使用ABCA 2敲除和敲入转基因小鼠来检查ABCA 2在与前列腺癌的TRAMP小鼠模型杂交的小鼠中胆固醇代谢、生理学和前列腺肿瘤发展/治疗反应中的作用。将分析来源于敲除和敲入小鼠的小鼠胚胎成纤维细胞（MEF）和用诱导型ABCA 2表达或RNA干扰稳定转染的前列腺癌细胞（PCS、DU 145、LNCaP）对ABCA 2水平变化的反应。将检查ABCA 2表达对增殖、胆固醇运输和药物治疗反应的影响。最终目标是利用转基因动物模型、MEFs和人前列腺癌细胞了解ABCA 2的细胞和生理功能。

DESCRIPTION (provided by applicant): Overexpression of the ATP binding cassette (ABC) transporter, ABCA2, has been linked to resistance to estramustine, a drug used to treat hormone-refractory prostate cancer. ABCA2 has a putative role in trafficking cholesterol, steroids and lipids into endolysosomes, suggesting a role in human disease, including cancer and atherosclerosis. To date, forced over-expression of ABCA2 in cell lines has been the only tool used to investigate its function. The studies outlined in this proposal use ABCA2-knockout and -knock-in transgenic mice to examine the role of ABCA2 in cholesterol metabolism, physiology and prostate tumor development/treatment response in mice crossed to the TRAMP mouse model of prostate carcinoma. Mouse embryonic fibroblasts (MEFs), derived from knockout and knock-in mice, and prostate cancer cells (PCS, DU145, LNCaP), stably transfected with inducible ABCA2 expression or RNA interference, will be analyzed for response to changes in ABCA2 levels. Effects of ABCA2 expression on proliferation, cholesterol trafficking and drug treatment response will be examined. The ultimate goal is to understand the cellular and physiological function of ABCA2 using transgenic animal models, MEFs and human prostate cancer cells.