Epigenetic response of imprinted domains during carcinogenesis.

backgroundImprinted domains have been identified as targets for aberrant DNA methylation during carcinogenesis, but it remains unclear when these epigenetic alterations occur and how they contribute to tumor progression. Epigenetic instability at key

resultsWe report that imprinted domains remain stable in benign processes but are highly susceptible to epigenetic alterations in infiltrative lesions. The preservation of DNA methylation within imprinted domains in benign tumors throughout their duration suggests that imprinted genes are not involved with the initiation of carcinogenesis or the growth of tumors. However, the frequent detection of DNA methylation changes at imprinting control regions in infiltrative lesions suggest that imprinted genes are associated with tumor cells gaining the ability to defy tissue boundaries.

conclusionOverall, this study demonstrates that imprinted domains are targeted for DNA hypermethylation when benign tumor cells transition to malignant. Thus, monitoring DNA methylation within imprinted domains may be useful in evaluating the progression of neoplasms.