Hypomethylation of Dual Specificity Phosphatase 22 Promoter Correlates With Duration of Service in Firefighters and Is Inducible by Low-Dose Benzo[a]Pyrene

Division of Environmental Genetics and Molecular Toxicology, Department of Environmental Health, Center for Environmental Genetics, University of Cincinnati Cancer Institute, College of Medicine, University of Cincinnati, Cincinnati, OH, USA.
Journal of occupational and environmental medicine / American College of Occupational and Environmental Medicine (Impact Factor: 1.63). 07/2012; 54(7):774-80. DOI: 10.1097/JOM.0b013e31825296bc
Source: PubMed


Firefighters (FFs) are chronically exposed to smoke and products of incomplete combustion, which frequently contain polycyclic aromatic hydrocarbons (PAHs). This study examined the possibility of an association between PAH-induced epigenetic alterations and occupational firefighting exposure.
Promoter methylation was analyzed in four genes in blood DNA from 18 FFs and 20 non-FFs (controls). Jurkat and human normal prostate epithelial cells were treated with benzo[a]pyrene to ascertain the epigenetic effects of this type of agent.
Firefighters had a higher prevalence of dual specificity phosphatase 22-promoter hypomethylation in blood DNA (P = 0.03) and the extent of hypomethylation correlated with duration of firefighting service (P = 0.04) but not with age. Benzo[a]pyrene reduced promoter methylation and increased gene expression of the same gene in Jurkat and normal prostate epithelial cells.
Cumulative occupational exposure to combustion-derived PAHs during firefighting can cause epigenetic changes in promoters of specific genes.

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