Antiproliferative activity of hop extracts in tumor cells

BATTISTA A; IBAÑEZ IL; ARRUNÁTEGUI L; CERDÁN M; POLICASTRO LL; MOLINARI B; DURÁN H

Pinamar, Argentina

Congreso; XLI Reunión Annual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular, 10th Congress of Panamerican Association for Biochemistry and Molecular Biology; 2005

Previous reports demonstrated multiple biological effects of humulones or a-acids from hop. The aim of this study was to evaluate the antiproliferative and antioxidant activity of hop extracts in human tumor cell lines (MCF-7, T47D, PAJU). Hop extracts used herein are pure, standardized solutions of iso-a-acids: hexahop gold (HH), tetrahop gold (TH) and isohop (IH) (Haas Hop Products, Inc.). Cell cultures were treated with the different extracts (0-100 µg/ml) for 24 h and dose-response curves were obtained. Proliferative activity was evaluated by MTT assay, apoptosis by staining with Hoescht33258 and antioxidant capacity by determining the oxidation of 2’,7’ dichlorofluorescin (DCFH). Results demonstrated a dose-dependent inhibition of cell growth in all the cell lines treated with HH (p<0.001) and TH (p<0.001). This inhibition was significant as from 25 µg/ml in MCF-7 and PAJU cells and as from 100 µg/ml in T47D. Conversely, no significant growth inhibition was induced by IH in these cell lines. Cells treated with HH, TH or IH did not show significant induction of apoptosis. Regarding DCFH oxidation a dose-dependent decrease was observed in all the cell lines treated with TH and HH. In conclusion, TH and HH induced cell growth inhibition, unrelated to induction of apoptosis and possibly associated to the antioxidant capacity of these extracts.