Epigenetic transitions: towards therapeutic targets.

Therapeutic approaches aimed at developing epigenetically-effective drugs are under intense investigation. Several classes of enzymes regulating histone acetylation and DNA methylation, which are required for epigenetic transitions, offer attractive targets for therapeutic interventions. Imbalances in histone acetylation and DNA methylation may play a significant role in the development of cancer and leukaemia and may provide a mechanistic rationale for targeting epigenetic modifications. Clinical trials designed to evaluate inhibitors of DNA methylation and histone deacetylase inhibitors are showing encouraging results in cancer patients. A growing quantity of data from preclinical research supports the notion that epigenetically-effective drugs could also find an application in other therapeutic areas. A number of emerging biomarkers may prove useful for monitoring drug effects and defining molecular signatures of response, toxicity and effective dose.