Green Tea Research Today is a free monthly online journal that collates and summarizes the latest research about Green Tea, including details on benefits, antioxidants, weight loss, diet, side effects.

Anti-proliferative effects of green tea polyphenol EGCG on Ha-Ras-induced transformation of intestinal epithelial cells.

Peng G, Wargovich MJ, Dixon DA

Department of Pathology and Microbiology, University of South Carolina School of Medicine, Columbia, SC, USA.

Oncogenic Ras mutations are frequently observed in colorectal cancer and participate in neoplastic transformation of intestinal epithelial cells. Accumulating evidence demonstrates the chemopreventive properties of green tea on colon carcinogenesis. Here we investigated the major green tea polyphenol, (-)-epigallocatechin-3-gallate (EGCG), to inhibit proliferation of intestinal epithelial cells (RIE-1) transfected with an inducible Ha-Ras(Val12) cDNA. EGCG inhibited cell proliferation induced by oncogenic Ras and blocked cell cycle transition at G1 phase via inhibition of cyclin D1 expression. The EGCG IC(50) was 42microM in transformed cells and 81microM in non-transformed cells. EGCG also promoted E-cadherin expression, which is downregulated by Ras transformation. This study demonstrates the potential of the natural compound EGCG as an effective adjuvant therapy for colon tumors bearing Ras mutations.

Published 19 June 2006 in Cancer Lett, 238(2): 260-70.
Full-text of this article is available online (may require subscription).

© 2004-2008 Green Tea Research Today. All Rights Reserved.