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Epigenetic effects of green tea polyphenols in cancer

    Susanne M Henning

    * Author for correspondence

    Center for Human Nutrition, David Geffen School of Medicine, University of California Los Angeles, 900 Veteran Avenue, Warren Hall 14-166, Los Angeles, CA 90095, USA.

    ,
    Piwen Wang

    Division of Cancer Research & Training, Charles R Drew University of Medicine & Science, Los Angeles, CA, USA

    ,
    Catherine L Carpenter

    Center for Human Nutrition, David Geffen School of Medicine, University of California Los Angeles, 900 Veteran Avenue, Warren Hall 14-166, Los Angeles, CA 90095, USA

    &
    David Heber

    Center for Human Nutrition, David Geffen School of Medicine, University of California Los Angeles, 900 Veteran Avenue, Warren Hall 14-166, Los Angeles, CA 90095, USA

    Published Online:https://doi.org/10.2217/epi.13.57

    Epigenetics describes heritable alterations of gene expression and chromatin organization without changes in DNA sequence. Both hypermethylation and hypomethylation of DNA can affect gene expression and the multistep process of carcinogenesis. Epigenetic changes are reversible and may be targeted by dietary interventions. Bioactive compounds from green tea (GT) such as (–)-epigallocatechin gallate have been shown to alter DNA methyltransferase activity in studies of esophageal, oral, skin, Tregs, lung, breast and prostate cancer cells, which may contribute to the chemopreventive effect of GT. Three out of four mouse model studies have confirmed the inhibitory effect of (–)-epigallocatechin gallate on DNA methylation. A human study demonstrated that decreased methylation of CDX2 and BMP-2 in gastric carcinoma was associated with higher GT consumption. It is the goal of this review to summarize our current knowledge of the potential of GT to alter epigenetic processes, which may be useful in chemoprevention.

    Papers of special note have been highlighted as: ▪ of interest ▪▪ of considerable interest

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