Severe impairment of antioxidant system in human hepatoma

Abstract

Catalase (CAT), glutathione-peroxidase (GSH-Px) activity and reduced glutathione content (GSH) were measured in patients who had hepatocellular carcinoma, and values compared with those of normal liver and liver adjacent to neoplastic tissue. The results showed a remarkable reduction of CAT in tumor and corresponding tumor-free tissue (P < 0.001 and P < 0.02, respectively). All neoplastic samples had a significant lower activity of CAT than the corresponding adjacent tumor-free tissue (P < 0.05). The GSH-Px activity of tumor tissue also was lower than normal (P < 0.001) but similar to that of adjacent tissue. No correlation was noted between the two enzyme activities. Glutathione content was extremely low in tumor (P < 0.001) and even in tumor-free tissue (P < 0.05) when compared with normal liver. In all cases the content of GSH in neoplastic tissue was lower than that of the corresponding tumor-free tissue (P < 0.05). Whereas in normal liver the activity of GSH-Px was positively correlated with the content of GSH, in the neoplastic tissue such a relationship disappeared. All these findings suggest that the antioxidant system of hepatocellular carcinoma cell is severely impaired.