BRG1介导化疗期间乳腺癌CTC升高及耐药的机制研究

项目名称： BRG1介导化疗期间乳腺癌CTC升高及耐药的机制研究

项目编号： No.81502269

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 医药、卫生

项目作者： 刘笑然

作者单位： 北京大学

项目金额： 18万元

中文摘要： 临床研究证实化疗阶段乳腺癌患者血循环肿瘤细胞（CTC）增多预示耐药，然而其机制尚不明确。既往报道EMT与CTC数量变化及耐药密切相关。本课题组已发现：抑制乳腺癌细胞BRG1表达后EMT标志基因Snail下调、细胞迁移能力减弱、药敏性增强；同时我们还发现Snail与经典耐药基因p53存在互作关系。据此，本项目拟采用最新的多肽-纳米磁珠专利技术获取CTC并检测目的基因表达；并利用乳腺癌细胞系在体、内外条件下对BRG1-Snail-p53通路各环节设计正、反实验，明确该通路调控乳腺癌EMT及耐药；本研究还将采用最新的NanoPro技术通量筛选p53可能的下游靶基因，从而完整阐述BRG1-Snail-p53通路调控乳腺癌患者化疗后CTC数量及药敏性变化的机制；项目中的新技术有效克服了CTC样本稀缺而导致的机制研究壁垒，预期成果可为CTC检测技术的深化发展以及制定更为合理的乳腺癌化疗策略提供理论基础

中文关键词： 乳腺肿瘤；Brahma相关基因；循环肿瘤细胞；化疗耐药

英文摘要： Several clinical trials have recently demonstrated that increased circulating tumor cell (CTC) number in response to chemotherapy was highly associated with chemoresistance in breast cancer. However, the mechanism underline this phenomena remain unclear. It has been reported that EMT have closed connection with CTC number changes and chemoresistance as well. Our previous works found that inhibition of chromatin remodeling factor BRG1 in breast cancer cell leads to a series of biological changes including down-regulation of Snail (An EMT marker gene), reduced cell migration ability and enhanced cell sensitivity to chemotherapy; furthermore, we also found a protein-protein interaction between Snail and p53. In view of these findings, we aim to uncover the mechanism of BRG1-Snail-p53 axis regulated variation of CTC cell number and chemosensitivity during breast cancer chemotherapy by design overdrive and rescuer experiments targeting each factor in BGR1-Snail-p53 axis. Peptide-magnetic nanoparticles based CTC enrichment technology was used in present study to collect the CTC numbers of patients and to test certain gene expression subsequently. This new method possess similar specificity and better sensitivity in capturing CTC as compared with conventional testing system (CellsearchTM), and thus provide a high quality of exploring platform for our mechanism research; meanwhile, we also applied high throughput simple western charge technology (ProteinSimple NanoProTM system) in this study, thus allowed us to acquire substantial information such as abundance and modification of certain proteins in mircoscale clinical sample. In all, the expected achievement of our study will provide a better understanding and usage of CTC number variation after chemotherapy, and improve refinement of current clinical intervention strategy against metastatic breast cancer.

英文关键词： breast cancer;BRG1;circulating tumor cell;chemoresistance