Transforming growth factor beta 1 differentially regulates alpha-fetoprotein and albumin in HuH-7 human hepatoma cells.
Transforming growth factor beta 1 (TGF-beta 1) is known to inhibit hepatocyte growth in vitro and in vivo. In this study, we analyzed the effect of TGF-beta 1 on alpha-fetoprotein (AFP) and albumin gene expression in HuH-7 human hepatoma cells. TGF-beta 1 inhibited cell growth in a dose dependent manner. The cellular secretion rate of AFP but not albumin was suppressed significantly by TGF-beta 1. TGF-beta 1 caused a significant reduction in the level of AFP mRNA. In contrast, the levels of albumin mRNA or beta-actin mRNA were not changed by TGF-beta 1. In transient transfection experiments, TGF-beta 1 resulted in selective repression of AFP promoter activity. These results suggest that TGF-beta 1 is one of the key factors involved in the differential regulation of the AFP gene and the albumin gene.
Nakao
K
K
First Department of Internal Medicine, Nagasaki University School of Medicine, Japan.
Nakata
K
K
Mitsuoka
S
S
Ohtsuru
A
A
Ido
A
A
Hatano
M
M
Sato
Y
Y
Nakayama
T
T
Shima
M
M
Kusumoto
Y
Y
D006528:Carcinoma, Hepatocellular; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D015500:Chloramphenicol O-Acetyltransferase / Q000235:genetics / Q000378:metabolism; D006801:Humans; D008113:Liver Neoplasms; D012333:RNA, Messenger / Q000187:drug effects / Q000235:genetics*; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D012709:Serum Albumin / Q000096:biosynthesis / Q000235:genetics*; D014162:Transfection; D016212:Transforming Growth Factor beta / Q000494:pharmacology*; D000509:alpha-Fetoproteins / Q000235:genetics*
D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins; D012709:Serum Albumin; D016212:Transforming Growth Factor beta; D000509:alpha-Fetoproteins; D015500:Chloramphenicol O-Acetyltransferase