Antitumor promoting activity of (−)-epigallocatechin gallate, the main constituent of “Tannin” in green tea
Article first published online: 11 JAN 2006
Copyright © 1987 John Wiley & Sons, Ltd.
Volume 1, Issue 1, pages 44–47, March 1987
How to Cite
Yoshizawa, S., Horiuchi, T., Fujiki, H., Yoshida, T., Okuda, T. and Sugimura, T. (1987), Antitumor promoting activity of (−)-epigallocatechin gallate, the main constituent of “Tannin” in green tea. Phytother. Res., 1: 44–47. doi: 10.1002/ptr.2650010110
- Issue published online: 11 JAN 2006
- Article first published online: 11 JAN 2006
- Manuscript Accepted: 23 MAR 1987
- Manuscript Received: 16 MAR 1987
- Cancer Research from the Ministry of Education, Science and Culture
- Ministry of Health and Welfare, Japan
- Foundation for Promotion of Cancer Research and the Princess Takamatsu Cancer Research Fund
(−)-Epigallocatechin gallate (EGCG) is the main polyphenolic constituent of extracts of green tea. EGCG slightly inhibited specific binding of [3H] 12-0-tetradecanoylphorbol-13-acetate ([3H]TPA) to a particulate fraction of mouse skin, and caused a prompt decrease in the phorbol ester receptor number in mouse skin. It also inhibited the activation of protein kinase C by teleocidin. In week 25 of a two-stage carcinogenesis experiment in mouse skin, tumors were found in 53% of the mice treated with 7,12-dimethylbenz(a)anthracene (DMBA) plus teleocidin, but in only 13% of those treated with DMBA plus teleocidin and EGCG. The average number of tumors per mouse in these groups was 2.1 and 0.1, respectively. No tumors were found in other groups treated with DMBA alone or teleocidin and EGCG alone. Thus EGCG inhibited tumor promotion by teleocidin.