Amplification of BCR protein associated with oncogenesis in human hepatocellular carcinoma.
The BCR gene is located on human chromosome 22. The normal cellular BCR gene encodes a 160,000-dalton phosphoprotein associated with a serine/threonine kinase activity. The BCR protein is involved in signal transduction. We investigated the expression of the BCR protein in hepatocellular carcinoma (HCC), surrounding noncancerous liver tissue, liver cirrhosis (LC), chronic hepatitis (CH), and normal liver with immunohistochemistry and a western blot analysis. BCR immunoreactivity was detected using a monoclonal antibody. In normal liver, and both CH and LC without association of HCC, the immunoreactivity of the BCR protein was minimal. In contrast, 73% (22 of 30) of noncancerous liver tissue adjacent to the HCC and 40% (12 of 30) of HCC expressed BCR protein; this difference was statistically significant (P < 0.01). The expression of the BCR protein expression correlated with the degree of histological differentiation of HCC (P < 0.05). In addition, the amplification of BCR protein in noncancerous cells was supported by the detection of specific protein using a western blot analysis. In two cases, the expression of BCR protein occurred only in overtly malignant HCC cells. As a result, the expression of the BCR protein may be associated with oncogenesis in human HCC.
Miyazaki
Y
Y
Third Department of Internal Medicine, Niigata University School of Medicine, Japan.
Mitsuma
T
T
Ichida
T
T
Odazima
H
H
Ishihara
K
K
Asakura
H
H
D000368:Aged; D015152:Blotting, Northern; D015139:Blotting, Southern; D015153:Blotting, Western; D006528:Carcinoma, Hepatocellular / Q000235:genetics / Q000378:metabolism*; D005260:Female; D015870:Gene Expression; D006521:Hepatitis, Chronic / Q000378:metabolism; D006801:Humans; D008099:Liver / Q000378:metabolism; D008103:Liver Cirrhosis / Q000378:metabolism; D008113:Liver Neoplasms / Q000235:genetics / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D015513:Oncogene Proteins / Q000096:biosynthesis* / Q000235:genetics; D011505:Protein-Tyrosine Kinases; D011518:Proto-Oncogene Proteins; D051562:Proto-Oncogene Proteins c-bcr; D012333:RNA, Messenger / Q000235:genetics; D015398:Signal Transduction
D015513:Oncogene Proteins; D011518:Proto-Oncogene Proteins; D012333:RNA, Messenger; D011505:Protein-Tyrosine Kinases; C496613:BCR protein, human; D051562:Proto-Oncogene Proteins c-bcr