In vitro induction of the anticarcinogenic marker enzyme, quinone reductase, in human hepatoma cells by food extracts

The effect of vegetable extracts on the activity of the anticarcinogenic phase II marker enzyme, quinone reductase (QR), was investigated by using human Hep G2 cells as the model system. Hep G2 cells were less sensitive than murine Hepalc1c7 cells to QR-inducible compounds such as Lert-butylhydroquinone which have been widely used to examine the QR-inducing activity of the compounds. However, among 45 different vegetable samples, art extract of ashitaba clearly induced QR activity in Hep G2 cells. Ashitaba is therefore considered to have contained certain substances that could induce QR activity, and such induction may play a role in the amicarcinogenic action of vegetables. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved.