Human tumor cell growth inhibition by nontoxic anthocyanidins, the pigments in fruits and vegetables

Anthocyanidins, the aglycones of anthocyanins, impart brilliant colors in many fruits and vegetables. The widespread consumption of diets rich in anthocyanin and anthocyanidins prompted us to determine their inhibitory effects on human cancer cell proliferation. Five anthocyanidins, cyanidin (1), delphinidin (2), pelargonidin (3), petunidin (4) and malvidin (5), and four anthocyanins, cyanidin-3-glucoside, cyanidin-3-galactoside, delphinidin-3-galactoside and pelargonidin-3-galactoside were tested for cell proliferation inhibitory activity against human cancer cell lines, AGS (stomach), HCT-116 (colon), MCF-7 (breast), NCI H460 (lung), and SF-268 (Central Nervous System, CNS) at 12.5-200 mug/mL concentrations. The viability of cells after exposure to anthocyanins and anthocyanidins was determined by MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) colorimetric methods. The anthocyanins assayed did not inhibit cell proliferation of cell lines tested at 200 mug/mL. However, anthocyanidins showed cell proliferation inhibitory activity. Malvidin inhibited AGS, HCT-116, NCI H460, MCF-7 and SF-268 cell growth by 69, 75.7, 67.7, 74.7 and 40.5%, respectively, at 200 mug/mL. Similarly, pelargonidin inhibited AGS, HCT-116, NCI-H460, MCF-7 and SF-268 cell growth by 64, 63, 62, 63 and 34%, respectively, at 200 mug/mL. At 200 mug/mL, cyanidin, delphinidin and petunidin inhibited the breast cancer cell growth by 47, 66 and 53%, respectively. This is the first report of tumor cell proliferation inhibitory activity by anthocyanidins. (C) 2004 Elsevier Inc. All rights reserved.