Pharmacoepigenetics

Summary

Pharmacoepigenetics is an emerging field that studies the underlying epigenetic marking patterns that lead to variation in an individual's response to medical treatment. Due to genetic heterogeneity, environmental factors, and pathophysiological causes, individuals that exhibit similar disease expression may respond differently to identical drug treatments. Selecting treatments based on factors such as age, body-surface area, weight, gender, or disease stage has been shown to incompletely address this problem, so medical professionals are shifting toward using patient genomic data to select optimal treatments. Now, an increasing amount of evidence shows that epigenetics also plays an important role in determining the safety and efficacy of drug treatment in patients. Epigenetics is a bridge that connects individual genetics and environmental factors to explain some aspects of gene expression. Specifically, environmental factors have the potential to alter one's epigenetic mechanisms in order to influence the expression of genes. For example, smoking cigarettes can alter the DNA methylation state of genes and thereby expression of genes through different mechanisms. Epigenetic changes in genes caused by factors such as environment can result in abnormal gene expression and the initiation of diseases. The progression of diseases further alters the epigenetic patterns of the whole genome. While epigenetic changes are generally long lasting, and in some cases permanent, there is still the potential to change the epigenetic state of a gene. Thus, drugs have been developed to target aberrant epigenetic patterns in cells to either activate or suppress the epigenetically modified gene expression gene expression. This is known as epigenetic therapy. Besides being drug targets, epigenetic changes are also used as diagnostic and prognostic indicators to predict disease risk and progression, and this could be beneficial for the improvement of personalized medicine.