基于可控组装微纳界面的循环肿瘤细胞多维度分型富集及临床应用

Detecting, isolating, and analyzing circulating tumor cell (CTC) is of great clinical significance in cancer diagnosis, treatment assessment, prognostic monitoring, and drug resistance mechanisms. Most of current methods focus on counting the number of CTC, which unfortunately miss the characterization of cancer cell subpopulations, and are incapable of releasing different subtypes of CTC correspondingly, leading to the limited clinical relevance. In this project, aptamers against different biomarkers for different types of CTC will be evolved in complex conditions. The nanoparticle-aptamer conjugates with multivalent binding affinity will be constructed to greatly improve the capture efficiency, and the controllable assembly of aptamer density on nanoparticle will be used to provide a series of molecules with different binding affinities to realize CTC subpopulation recognition. Using the nanoparticle-aptamer conjugates with various binding capacity modified microfluidic chip and controllable release strategy, the new strategy sorts CTC according to levels of two subtype markers and thereby separates them into their corresponding subpopulations. More importantly, breast cancer samples will be analyzed and subtyped for understanding of CTC phenotype and clinical relevance. The affinity probes, multivalent DNA aptamer nanospheres, microfluidic devices, and CTC enrichment method developed in this project will provide useful tools for cancer diagnosis, metastasis monitoring, assessment of resistance to therapy and basic research.

循环肿瘤细胞（CTC）分析在肿瘤分期、疗效评估、预测肿瘤进展或复发、抗药性研究等方面具有重大意义。目前CTC富集平台集中在总数分析，无法获得不同分型CTC数目，难以分别释放各种类型CTC进行下游分析，因此难以建立较好临床相关性。本项目拟通过发展复杂体系中核酸适体筛选技术，获得多条复杂体系中能特异性识别多种类型CTC标志物的核酸适体；通过适体纳米探针的多价结合提高亲和能力，并调控适体纳米探针的修饰密度，获得梯度亲和力适体纳米探针，实现CTC分型识别；在不同芯片结构单元依次修饰不同亲和力纳米适体探针，结合通道区域结构设计及可控释放，实现根据双标志物的多维度分型富集及选择释放；通过临床样品分析，建立乳腺癌各类型CTC的临床相关性，为深入理解乳腺癌CTC的转移机制及探究各类型CTC生物学意义提供科学依据。项目的成功实施将为癌症的精准诊断、转移监测、抗药性评估提供科学依据。

循环肿瘤细胞（CTC）分析在肿瘤分期、疗效评估、预测肿瘤进展或复发、抗药性研究等方面具有重大意义。目前CTC富集平台集中在总数分析无法获得不同分型CTC数目，难以建立较好临床相关性。本项目通过筛选获得了循环肿瘤细胞标志物EpCAM、CSV、PD-L1等多种靶标的核酸适体序列；发展了流动多价、拓扑匹配多价、DNA纳米光刻技术、优势互补多价识别策略，构筑了亲和力可调控适体纳米微流控芯片；实现了临床病人样品，并探究了不同类型癌CTC在临床诊断和肿瘤进展中的意义。在项目实施过程中在国际化学期刊上发表论文30 篇，申请专利3项，培养优秀青年基金获得者1人，培养/共同培养了生物分析化学博士4名，硕士2名。