Effects of quercetin, a plant flavonol, on the two‐stage transformation in vitro

摘要

AbstractQuercetin was examined for the effects on the two‐stage chemical transformation of BALB/3T3 cells. Quercetin showed initiating action to induce transformation in the cells which were treated with quercetin and subsequently with 0.49 μM 12‐O‐tetradecanoyl‐phorbol‐13‐acetate (TPA). Both the proportion of dishes with transformed foci and the average number of foci per dish increased with the concentration of quercetin (15–45 μM). However, initiating treatment with quercetin did not induce transformation without subsequent TPA treatment. Quercetin inhibited the promotion caused by 0.49 μM TPA in the transformation initiated by 1.9 μM 3‐methylcholanthrene (MCA). The inhibitory effect of 30 μM quercetin was 56 in the number of foci per dish. Thus quercetin was found to have initiating effect on the transformation of BALB/3T3 cells, but to restrain