title: Expression of the c-met protooncogene in human hepatocellular carcinoma.
abstract: The c-met protooncogene is a growth factor receptor with tyrosine kinase activity. Recently the hepatocyte growth factor was identified as the ligand for this receptor. Because the hepatocyte growth factor is a most potent mitogen in hepatocytes, possible involvement of c-met expression in hepatocarcinogenesis is suspected. In this study, we examined c-met expression in 23 hepatocellular carcinoma cases by means of Northern-blot analysis and an immunohistochemical study. Northern-blot analysis revealed c-met mRNA expression in the tumors of 6 of 19 patients (31.6%); in the immunohistochemical study, c-met protein was detected in 16 of 23 patients (69.6%). With both methods, c-met was found to be overexpressed in hepatocellular carcinoma compared with the surrounding normal liver. Comprehensive analysis showed that c-met protein expression was correlated with poor-to-moderate differentiation of cancer cells (p < 0.05). Tumor proliferative activity of hepatocellular carcinoma was evaluated by means of Ki-67 labeling index. All cases with increased tumor proliferative activity showed c-met protein expression, although the elevation of proliferative activity in the c-met-positive group was not statistically significant. These data suggest that the overexpression of c-met plays an important role in the development of hepatocellular carcinoma.
authors.affiliation: First Department of Medicine, Osaka University Medical School, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Suzuki
authors.forename: N
authors.initials: N
authors.lastname: Hayashi
authors.forename: Y
authors.initials: Y
authors.lastname: Yamada
authors.forename: H
authors.initials: H
authors.lastname: Yoshihara
authors.forename: Y
authors.initials: Y
authors.lastname: Miyamoto
authors.forename: Y
authors.initials: Y
authors.lastname: Ito
authors.forename: T
authors.initials: T
authors.lastname: Ito
authors.forename: K
authors.initials: K
authors.lastname: Katayama
authors.forename: Y
authors.initials: Y
authors.lastname: Sasaki
authors.forename: A
authors.initials: A
authors.lastname: Ito
mesh_terms: D000328:Adult; D000368:Aged; D015152:Blotting, Northern; D006528:Carcinoma, Hepatocellular / Q000378:metabolism* / Q000473:pathology; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism; D019859:Proto-Oncogene Proteins c-met; D012333:RNA, Messenger / Q000378:metabolism; D020794:Receptor Protein-Tyrosine Kinases / Q000235:genetics* / Q000378:metabolism
chemical_list: D011518:Proto-Oncogene Proteins; D012333:RNA, Messenger; D019859:Proto-Oncogene Proteins c-met; D020794:Receptor Protein-Tyrosine Kinases