基于磁悬浮的癌症干细胞分离方法研究

Metastasis and recurrence of tumor are responsible for 90% of cancer-associated death. The existence of cancer stem cells (CSCs) in tumor is the key of metastasis and recurrence of tumor, current clinical treatment cannot efficiently kill CSCs. Thus, study of universal profile of CSCs could lead to more efficient anti-cancer therapy and cancer diagnosis. Isolation method limited the research of CSCs now. The key question is how to combine high efficient magnetic levitation isolation with universal intracellular biomarker to achieve high-throughput, high resolution, and universal isolation. In this proposal, we try to synthesis CSCs specific enzyme substrate modified Gd complex. The cytosolic enzyme digests the substrates in Gd complex, which could make the Gd retain inside CSC. And the specific magnetism property of CSCs increase. In a magnetic medium, CSCs and non-CSCs magnetically levitated at different height due to the difference of the specific magnetism property of CSCs and non-CSCs under an external magnetic field. The proposed methods have the high resolution of fluorescence-activated cell sorting and the high-throughput of magnetic beads based cell sorting, and did not rely on surface markers that are easily regulated by tumor microenvironment and personal immune system. We plan to study the epigenomic profile of the isolated CSCs and find universal signature for better early stage cancer diagnose by using our next generation DNA sequencing platform.

百分之九十的癌症致死病例由癌转移和肿瘤复发造成，癌症干细胞(CSCs)的存在是其关键因素，现有的治疗手段无法有效杀死CSCs。因此研究CSCs的表观基因组学特征是实现癌症早期诊断和治疗的有效途径。目前该领域的瓶颈是缺乏有效的CSCs分离手段，关键问题是如何将高分辨的磁悬浮细胞分离与细胞内标志物相结合，以实现高通量、高精度、普适性的CSCs分离。本项目拟合成带有癌症干细胞特异性酶底物的钆络合物，通过酶对底物的降解，使钆富集在癌症干细胞中使其磁化率升高。在磁性溶液中，利用癌症干细胞与非癌干细胞之间磁化率的差别，产生磁悬浮高度差，从而实现细胞分选。本方案兼具流式细胞分选的高精度和磁性微球分离的高通量，并且不依赖于易受到肿瘤微环境影响的表面标志物，可实现高效的癌症干细胞分离。利用二代测序平台研究分离得到的癌症干细胞的表观基因组学特征，为实现更准确的癌症早期诊断提供有力支持。

百分之九十的癌症致死病例由癌转移和肿瘤复发造成，癌症干细胞(CSCs)的存在是其关键因素，现有的治疗手段无法有效杀死CSCs。目前CSC研究的瓶颈是缺乏有效的CSCs分离手段，关键问题是如何将高分辨的磁悬浮细胞分离与细胞内标志物相结合，以实现高通量、高精度、普适性的CSCs分离。本项目执行期间设计与制作了细胞磁悬浮装置、合成了靶向癌干细胞配合物，实现了癌干细胞分离与验证。该分离方法，无需流式细胞仪。成本低廉，通量高。可用于从多种肿瘤细胞中快速分离癌干细胞亚群。同时也可用于具有乙醛脱氢酶（ALDH）特征的正常干细胞的分离中，比如人造血干细胞。基于对癌干细胞检测的需求，发展了多种针对癌细胞的体外核酸标志物检测新方法与在体荧光/化学发光荧光探针。本项目取得成果共发表学术论文13篇，其中Chemical Science, 1篇，Analytical Chemistry, 2篇，Chemical Communication, 1篇，Analytica Chimica Acta，1篇。