Environmental pollution and DNA methylation: carcinogenesis, clinical significance, and practical applications

Abstract

Environmental pollution is one of the main causes of human cancer. Exposures to environmental carcinogens result in genetic and epigenetic alterations which induce cell transformation. Epigenetic changes caused by environmental pollution play important roles in the development and progression of environmental pollution-related cancers. Studies on DNA methylation are among the earliest and most conducted epigenetic research linked to cancer. In this review, the roles of DNA methylation in carcinogenesis and their significance in clinical medicine were summarized, and the effects of environmental pollutants, particularly air pollutants, on DNA methylation were introduced. Furthermore, prospective applications of DNA methylation to environmental pollution detection and cancer prevention were discussed.

Keywords

environmental pollution / DNA methylation / cancer / biomarker / diagnosis / therapy / prevention

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Acknowledgements

The author gratefully acknowledges Dr. GB Zhou (Institute of Zoology, Chinese Academy of Sciences, Beijing) for providing the idea to write the current article. This work was supported by the 973 Program (2011CB510104) and the National Natural Science Foundation of China (81272617).

Compliance with ethics guidelines

Yi Cao declares no conflict of interest. This manuscript is a review article and does not involve a research protocol requiring approval by the relevant institutional review board or ethics committee.

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2014 Higher Education Press and Springer-Verlag Berlin Heidelberg