摘要
Cancer chemoprevention, a desirable and important facet of biomedical research, Provides a practical approach to identify potentially useful inhibitors of cancer development, and offers an opportunity to study the mechanism of carcinogenesis. During the recent past a nuInber of compounds have been tested for their anticarcinogenic potential specially constituents of human diet. The enzyme y-glutamyl transpeptidase (CGT), which catalyses the transfer of glutamyl gnups of peptides to other peptides and amino acids, has been proposed as a marker of cell proliferation and neoplasia. It also serves as a tool to evaluate the carcinogenic and cocareinogenic poential of environmental toxicants. In the present investigations, GGT activity induced by carcinogenic polycyclic aromatic hydrocarbons, viz. 7, 12-dimethyl-benz(a) anthracene (DMBA) and benzo(a)Pyrene (BaP was significantly inhibited by diallylsulfide (DAS) and indole-3-carbinol (13C) in mouse skin. DAS and 13C are Constituents of garlic. A significant inhibition in GGT levels was also observed in a strong mitogen (12-o-tetradecanoyl phorbol-13-acelate) induced activity by pretreatment of DAS/13C in mouse skin. Therefore these dielary constituents seem to be strong modifiers of chemically induced carcinogenesis.