[Relationship between methylation status of gamma-glutamyl transpeptidase (GGT) genes and abnormal expression of its enzyme proteins in tissues of human hepatomas].
OBJECTIVE
To explore the mechanism of expression and alteration of gamma-glutamyl transpeptidase (GGT) genes during the development of human hepatomas.


METHODS
The total GGT protein and total RNA were purified in human hepatomas, adjacent paracancerous and distal cancerous tissues. The specific activities of total GGT, membrane-combine GGT and soluble GGT were investigated, the GGT gene of 5'-NC region was amplified by using a nest RT-PCR assay, and methylation status of GGT gene M3 site were analyzed in the present study.


RESULTS
An increasing tendency (P < 0.05) of total RNA concentrations was found from cancer in distal cancerous tissues; the specific activities (U/g) of total GGT, membrane-combine GGT and soluble GGT were significantly higher (P < 0.05) in hepatomas than those in adjacent paracancerous or and that distal cancerous tissues; and the frequencies of amplified fragment and hypomethylated M3 site of GGT 5'-NC region genes were 100% and 75% in hepatomas, 85% and 55% in adjacent cancerous, and 75% and 50% in distal cancerous tissues, respectively.


CONCLUSIONS
The present data suggest that the abnormal expression of GGT proteins in hepatomas was related to hypomethylation status of GGT genes, and that the fragment analysis of the GGT genes might be a sensitive assay to monitor the hepatic cell canceration.
Yao
D
D
Affiliated Hospital, Nantong Medical College.
Tang
Q
Q
Meng
X
X
D006528:Carcinoma, Hepatocellular / Q000201:enzymology*; D019175:DNA Methylation; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000201:enzymology*; D008297:Male; D008875:Middle Aged; D020133:Reverse Transcriptase Polymerase Chain Reaction; D005723:gamma-Glutamyltransferase / Q000235:genetics* / Q000378:metabolism
D005723:gamma-Glutamyltransferase