Abstract CN12-03: Epigenetic targets of sulforaphane and epigallocatechin gallate in cancer prevention

Interest in cancer epigenetics has arisen from the fact that epigenetic processes affect many aspects of tumor formation and progression. The reversibility of epigenetic changes that may arise in early tumorigenesis is an important aspect of their potential in approaches for cancer prevention. Many of the components of the human diet have bioactive effects that lead to reversal of epigenetic aberrations in cancer. We have found that both (-)-epigallocatechin-3-gallate (EGCG) from green tea and sulforaphane (SFN) from cruciferous vegetables are able to down-regulate telomerase in breast cancer cells. This occurs through epigenetic modifications of the promoter region of hTERT, the gene that encodes the catalytic subunit of telomerase. Since telomerase promotes tumor formation and is active in about 90% of cancers, this epigenetic inhibition of its catalytic subunit gene may have considerable potential in breast cancer prevention. Our studies also indicate that these bioactive dietary compounds are able to convert estrogen-receptor (ER)-negative breast cancer cells to ER-positive breast cancer cells and to prevent the formation of highly lethal ER-negative breast cancer. This occurs through epigenetic modifications of the ERalpha gene in response to EGCG and SFN. These findings have significance in that ER-positive cells are amenable to breast cancer prevention or therapy with compounds such as tamoxifen while ER-negative cells confer few preventive or treatment options for pat...
Source: Cancer Prevention Research - Category: Cancer & Oncology Authors: Tags: DNA Methylation/Epigenetics, and Chromatin Regulation: Oral Presentations - Invited Abstracts Source Type: research