基于高通量测序的血浆游离DNA甲基化组分析新方法及其在肿瘤诊断与监测中的应用

项目名称： 基于高通量测序的血浆游离DNA甲基化组分析新方法及其在肿瘤诊断与监测中的应用

项目编号： No.81472857

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 医药、卫生

项目作者： 文路

作者单位： 北京大学

项目金额： 75万元

中文摘要： 血浆游离DNA中的异常甲基化CpG岛作为肿瘤生物标记物已有近二十年研究历史，但目前仍然缺乏同时具备高灵敏度（能检测含量和比例极少的靶目标）和高通量（能同时检测大量靶目标）特征的组学分析方法。在前期工作中，我们建立了一种基于高通量测序的DNA甲基化组分析新方法：甲基化CpG短串联扩增与测序法（MCTA-Seq）。结果显示，MCTA-Seq具有高灵敏（0.1~1%）地同时检测数千个甲基化CpG岛的能力。进一步，MCTA-Seq能从肝癌患者血浆游离DNA中检测到两千多个甲基化CpG岛，其中数百个为肿瘤特异性的、而在正常人外周血中检测不到的异常甲基化CpG岛。据此，我们拟：1）系统优化MCTA-Seq，并2）开展肝细胞癌和结直肠癌诊断和监测临床应用研究。以上研究旨在将MCTA-Seq建成一种高灵敏、高通量、低成本和操作简便的血浆游离DNA甲基化组分析方法，为其最终应用于临床肿瘤诊断与监测提供基础。

中文关键词： DNA甲基化；高通量测序；游离DNA；C09_肝和肝内胆管肿瘤；C08_结；直肠肿瘤

英文摘要： Aberrant methylation of CpG islands as cancer biomarkers have been discovered in plasma cell-free DNA for nearly twenty years. However, there is still a lack of omics analysis methods that are characterized as both high-sensitive (can detect targets of low abundance and proportion) and high through-put (can detect a large number of targets at the same time). In our previous work, we established a novel DNA methylome analysis method based on high-throughput sequencing: Methylated CpG Tandoms Amplification and Sequencing (MCTA-Seq). The results showed that MCTA-Seq is able to detect thousands of methylated CpG islands at high sensitivity of 0.1% to 1%. Further studies showed that MCTA-Seq was able to detect more than two thousands of methylated CpG islands from the plasma cell-free DNAs extracted from the peripheral blood of the hepatocellular carcinoma patients, including several hundreds of cancer-specific methylated CpG islands which were not detected in the peripheral blood of normal persons. Based on these previous studies, we apply for funding for 1) systematically optimizing MCTA-Seq; and 2) applying MCTA-Seq to analyze clinical samples of hepatocellular carcinoma and colorectal cancer patients for cancer detection and monitoring. These studies are aimed to accomplish MCTA-Seq as a high-sensitive, high through-put, low-cost and easy-operate DNA methylome analysis method for plasma cell-free DNA that can finally be applied in clinical cancer detection and monitoring.

英文关键词： DNA methylation;High-throughput sequencing;Cell-free DNA;Hepatocellular carcinoma;Colorectal cancer