新型DNA甲基化检测方法MeFISH在肿瘤诊断中的应用

DNA甲基化是基因组表观遗传修饰的一种。DNA甲基化异常是恶性肿瘤的一种特征性表现。我们前期建立了一种利用ICON探针，原位检测单细胞核内串联重复序列satellite DNA甲基化的原位检测方法，命名为MeFISH。本项目在前期试验的基础上，建立可检测散在重复序列和单拷贝序列DNA甲基化状态的MeFISH实验系统，并将MeFISH法用于多种肿瘤细胞株和临床标本中重复序列LINE-1和Alu，以及癌基因、抑癌基因和印记基因等单拷贝序列的DNA甲基化状态的检测。通过本研究，可使在荧光显微镜下检测单个细胞核和染色体水平的特定序列的DNA甲基化状态成为可能。本项目的完成，可为肿瘤表观遗传异质性的研究、肿瘤的诊断和预后判定提供新的检测手段。

DNA methylation is an epigenetic modification of the genome. Aberrant DNA methylation patterns are a characteristic feature of cancer.In our previous study, a new methylation-specific fluorescence in situ hybridization method, named MeFISH, was developed to visualize DNA methylation at satellite repeat sequences in individual cell nuclei in situ. This project aims to establish the MeFISH system for visulization of DNA methylation status of interspersed repeat sequences and single-copy sequences.In addition, MeFISH method would be used to detect DNA methylation status of repetitive, such as LINE-1 and Alu, and single-copy sequences, such as oncogenes, anti-oncogenes and imprinted genes, in human cancer cell lines and clinical tumor specimens. The project aims to develop a novel method for epigenetic heterogenity research, diagnosis and prognosis of cancer.