链置换反应用于高风险前列腺癌特异性外泌体miRNA的分析方法研究

High-risk prostate cancer is one of the most important threats to men’s health. Diagnosis and treatment are quite difficult. The maker of prostate specific antigen has false positive problems, so the investigation of novel diagnostic markers and the development of advanced detection methods are of great significance. Based on strand displacement reactions, this project aims to design novel biosensors for ultrasensitive detection of specific exocrine miRNA of high-risk prostate cancer. The relationship between exocrine miRNA and existing clinical indicators is also studied, which may be useful for the diagnosis and treatment of the disease. At present, exosome related studies mainly rely on traditional analytical methods, which cannot meet the needs of biomedical researches and disease theranostics applications. This project combines the advantages of nucleic acid probe assembly technology, nanotechnology and electrochemical technology. Magnetic nanomaterials are firstly employed for the separation and enrichment of the exosomes. Assembled DNA nanostructures are then used to construct structural orderly and controllable electrode interface. Multi-signal amplification strategies are performed based on strand displacement reactions. Electrochemical nanoprobes are introduced to realize stable signal output with high intensity. This project is supposed to achieve ultrasensitive detection of exocrine miRNA in serum, providing powerful technical supports for the early diagnosis of high-risk prostate cancer and the studies of disease mechanisms. It is of great significance to the further development of related biomedical researches.

高风险前列腺癌是危害男性健康最重要的问题之一，存在预测难、诊治困难等问题。常规的前列腺特异性抗原指标具有显著的假阳性问题，因此研究新型的诊断标志物和开发先进的检测方法具有重要的意义。本项目基于链置换反应创新性地设计生物传感方法，对高风险前列腺癌特异性外泌体miRNA进行超灵敏检测，深入研究该指标与现有临床指标的相关性，有望为该疾病的诊治提供更可靠的依据。目前外泌体相关研究涉及的传统分析方法无法满足生物医学研究及疾病诊治的应用需求。本项目结合了核酸探针组装技术、纳米技术与电化学技术的优势：使用磁性纳米材料对样品进行分离富集；设计组装核酸纳米结构，构建结构有序、可控的电极界面层；实施基于链置换反应的多重信号放大策略；引入电化学纳米探针，实现高强度的信号输出；最终实现外泌体miRNA超灵敏检测的目标，为高风险前列腺癌的诊断及疾病机制研究提供有力的技术支持，对相关生物医学研究的深入开展意义重大。

筛选先进的诊断标志物和开发性能优异的检测方法对于高风险前列腺癌的诊疗具有重要的意义。本项目结合链置换反应与各种DNA纳米结构变化，创新性地发展了多种生物传感方法，对高风险前列腺癌特异性外泌体miRNA进行了超灵敏检测。相关工作以项目申请书中预定的方案为原型，以高灵敏度、高选择性、低成本、便捷性等为综合考量的指标，进一步完善了检测方案。项目进展顺利，达到了申请时的各项预期目标，取得了较好的成果。共发表学术论文27篇，申请发明专利7项，已授权1项；获得中国分析测试协会科学技术奖一等奖等奖项。代表性研究成果如（1）基于DNA双足步行器与链置换反应的miRNA逻辑门系统、（2）基于多重链置换反应的miRNA超灵敏电化学传感器、（3）基于哑铃杂交链式反应与链置换反应的miRNA电化学传感器等可作为生物分析和临床分子诊断的工具，有望为高风险前列腺癌的诊断及疾病机制研究提供有力的技术支持。