Department of Preventive Medicine, Seoul National University College of Medicine, Seoul, Korea.
J Epidemiol. 2012;22(5):384-94. doi: 10.2188/jea.je20120003. Epub 2012 Aug 4.
Aberrant DNA methylation is associated with cancer development and progression. There are several types of specimens from which DNA methylation pattern can be measured and evaluated as an indicator of disease status (from normal biological process to pathologic condition) and even of pharmacologic response to therapy. Blood-based specimens such as cell-free circulating nucleic acid and DNA extracted from leukocytes in peripheral blood may be a potential source of noninvasive cancer biomarkers. In this article, we describe the characteristics of blood-based DNA methylation from different biological sources, detection methods, and the factors affecting DNA methylation. We provide a comprehensive literature review of blood-based DNA methylation as a cancer biomarker and focus on the study of DNA methylation using peripheral blood leukocytes. Although DNA methylation patterns measured in peripheral blood have great potential to be useful and informative biomarkers of cancer risk and prognosis, large systematic and unbiased prospective studies that consider biological plausibility and data analysis issues will be needed in order to develop a clinically feasible blood-based assay.
异常的 DNA 甲基化与癌症的发生和发展有关。有几种类型的标本可以测量 DNA 甲基化模式，并将其作为疾病状态（从正常生物学过程到病理状况）的指标进行评估，甚至可以作为对治疗的药理反应的指标。基于血液的标本，如无细胞循环核酸和从外周血白细胞中提取的 DNA，可能是无创性癌症生物标志物的潜在来源。在本文中，我们描述了来自不同生物来源的基于血液的 DNA 甲基化的特征、检测方法以及影响 DNA 甲基化的因素。我们全面回顾了基于血液的 DNA 甲基化作为癌症生物标志物的研究，并重点介绍了使用外周血白细胞进行的 DNA 甲基化研究。虽然外周血中测量的 DNA 甲基化模式具有成为癌症风险和预后有用且信息丰富的生物标志物的巨大潜力，但需要进行大型系统的、无偏的前瞻性研究，以考虑生物学合理性和数据分析问题，从而开发出一种临床可行的基于血液的检测方法。
