Elevated levels of transforming growth factor beta messenger RNA and its polypeptide in human hepatocellular carcinoma.
Malignant cells in culture express elevated levels of transforming growth factor beta 1 (TGF-beta 1) mRNA and secrete an abundant amount of TGF-beta protein, but little is known about the production of TGF-beta in human malignant tissues in vivo. We estimated the levels of TGF-beta 1 mRNA expression by Northern hybridization and measured TGF-beta protein using a radioreceptor assay in tumor tissues surgically obtained from six patients with hepatocellular carcinoma (HCC). TGF-beta 1 mRNA was expressed at much higher levels in HCC tissues from all the cases compared with normal human liver, suggesting an association of the activated TGF-beta 1 gene transcription with hepatocarcinogenesis. The content of TGF-beta was 207 +/- 121 ng/g wet tissue in the HCC tissue, and it showed correlation with the level of TGF-beta 1 mRNA in the tissue (r = 0.69; P less than 0.05). An immunohistochemical study demonstrated that TGF-beta 1 staining could be observed in HCC cells. These observations suggest that human HCC strongly expresses TGF-beta 1 mRNA in vivo, leading to a high content of TGF-beta protein.
Ito
N
N
Second Department of Internal Medicine, Osaka University Medical School, Japan.
Kawata
S
S
Tamura
S
S
Takaishi
K
K
Shirai
Y
Y
Kiso
S
S
Yabuuchi
I
I
Matsuda
Y
Y
Nishioka
M
M
Tarui
S
S
D000368:Aged; D015152:Blotting, Northern; D006528:Carcinoma, Hepatocellular / Q000235:genetics / Q000378:metabolism*; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000235:genetics / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism*; D011869:Radioligand Assay; D016212:Transforming Growth Factor beta / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism
D012333:RNA, Messenger; D016212:Transforming Growth Factor beta