Of humans and hamsters: comparative analysis of lipid peroxidation, glutathione, and glutathione-dependent enzymes during oral carcinogenesis

We examined the extent of lipid peroxidation and the amount of reduced glutathione (GSH), and activities of the GSH-dependent enzymes, glutathione peroxidase (GPx) and glutathione S-transferase (GST), in human oral tumour tissue and 7,12-dimethylbenz[a]anthracene-(DMBA)- hamster buccal pouch tumour tissues. Diminished lipid peroxidation in the oral and hamster tumours was accompanied by a significant reduction in the concentration of phospholipids and an increase in the cholesterol:phospholipid ratio. The concentration of glutathione and the activities of GPx and GST were raised in both human oral and hamster tumour tissues. Our results show that the patterns of changes in human oral squamous cell carcinomas and chemically-induced carcinomas of the hamster buccal pouch are similar.