[The expression of mutant p53 (mp53) protein in rat hepatic preneoplastic lesions induced by diethylnitrosamine (DEN)].

OBJECTIVE

To study p53 genes related to hepatocarcinogenesis.

METHODS

Using immunohistochemistry techniques, the relation between expression of mp53 protein, placental glutathione S-transferase (GST-P) and the cell proliferative activity was investigated in rat hepatic preneoplastic lesions induced by DEN and the control liver.

RESULTS

Two of five rats with hepatic prenoplastic lesions had mp53 protein expression which was seen only in a portion of large-sized hyperplastic nodules (HN) or GST-P positive foci at 5th week. The bromodeoxyuridine labeling indeX (BrdU-LI) in p53-positive HN or GST-P foci was significantly higher than that of p53-negative HN or GST-P-negative foci respectively (P < 0.05).

CONCLUSIONS

Mutation of p53 gene occurs in the early stage of hepatocarcinogenesis, and is responsible for the hepatocellular proliferations and hepatocarcinogenesis, and might become an additional tumor marker.