Dietary phytochemicals as epigenetic modulators in cancer

Abstract

Epigenetics refers to heritable changes in gene expression that are not attributable to changes in DNA sequence, but rather depend on alterations in DNA methylation, chromatin structure or microRNA profiles. Although epigenetic changes are heritable in somatic cells, these modifications are potentially reversible and make them attractive and promising targets in the prevention and therapy of cancer. Dietary phytochemicals, especially present in fruits, vegetables and beverages have recently shown considerable promise in affecting gene expression via reversible epigenetic mechanisms. These agents include tea polyphenols, genistein, curcumin, sulforaphane, isothiocynates, lycopene, resveratrol, quercetin, indol-3-carbinol, ellagitannin and organosulfur compounds. This chapter discusses the impact of environment, lifestyle and dietary factors on epigenetic alterations and presents considerable evidence that modulation of epigenetic targets by dietary phytochemicals is associated with the prevention and therapy of cancer. This chapter also emphasizes that an increased understanding of the anticancer effects of dietary phytochemicals offer new epigenetic targets and promising agents with more opportunities for prevention, and perhaps therapy of cancer.