Breast Cancer Implications of the Suppression of Estrogen Formation by Components of Red Wine and Grape Seeds

Shiuan Chen, Ph.D.
Beckman Research Institute of the City of Hope, Duarte California
ES8258

Background: Many epidemiologic studies have shown that diets high in fruits and vegetables can reduce cancer incidence with multiple studies focusing on wine and grape consumption. Other studies have shown that the production of estrogens in breast cancer tissue plays a major role in tumor progression. Aromatase, a P450 enzyme, synthesizes estrogen by converting 19-carbon androgens into 18-carbon estrogens. Aromatase is highly expressed in breast cancer tissue. Previous research from this and other laboratories has shown that extracts from red wine were shown to inhibit aromatase activity.

Advance: In their current publication, these investigators have identified a class of compounds called procyanidin B dimers as the most abundant aromatase inhibitors in red wine. High levels of these compounds have been found in grape seeds. Further laboratory analyses revealed that the most potent procyanidin B dimer competes with the androgen substrate for binding with the enzyme. Additional in vitro studies show that the dimers were able to reduce androgen-dependent tumor growth, indicating that these chemicals reduce the production of estrogens from the androgen substrates.

Implications: This study, and earlier work by the same team, demonstrates that procyanidin B dimers in red wine could be used as chemopreventive agents against breast cancer by inhibiting the conversion of androgens to estrogens in breast tissues. The researchers estimate that a single four-ounce glass of red wine daily could provide enough procyanidin B dimer to inhibit aromatase activity in an average post-menopausal woman.

Citation: Eng ET, Ye J, Williams D, Phung S, Moore RE, Young MK, Gruntmanis U, Braunstein G, Chen S. Suppression of estrogen biosynthesis by procyanidin dimers in red wine and grape seeds. Cancer Res. 2003 Dec 1;63(23):8516-22.