Role of beta-catenin in hepatocarcinogenesis of rats.
BACKGROUND
Beta-catenin has two distinct roles in E-cadherin mediated cell adhesion and carcinogenesis by activating the wnt/beta-catenin signaling pathway. One occurs at the cell-adhesion site, where cadherins are linked to the actin-based cytoskeleton. The other takes place in the cytoplasm and nuclei and is thought to regulate cell transformation. We studied the role of beta-catenin in hepatocarcinogenesis of rats.


METHODS
Fresh liver specimens were obtained from normal rats, and atypical hyperplasia livers and hepatocarcinoma tissues from model rats. The changes of beta-catenin in gene expression levels were detected by reverse transcriptase polymerase chain reaction (RT-PCR) in the different specimens separately. At the same time, their localization was observed immunohistochemically.


RESULTS
In the normal liver specimens, beta-catenin staining was seen in the cell membrane. In liver specimens of atypical hyperplasia, beta-catenin staining occurred in the cell cytoplasm of some cells as well as in the cell membrane of others. Immunohistochemically cancerous tissues showed the presence of beta-catenin in the cytoplasm and nuclei. RT-PCR revealed that the gene expression levels of beta-catenin were same in all samples.


CONCLUSIONS
The accumulation of beta-catenin in the cytoplasm and/or nuclei frequently occurs in hepatocarcinogenesis of rats. It may be an early event in the development of hepatocarcinoma of rats.
Department of Human Anatomy, Huaxi Medical Centre of Sichuan University, Chengdu 610041, China. wangqiming-6@163.com
Qi-Ming
QM
Wang
Kai-Ming
KM
Yang
Hong-Ying
HY
Zhou
Zhen-Hai
ZH
Yu
Xiao
X
Li
Hui-Jun
HJ
Yang
D000818:Animals; D006528:Carcinoma, Hepatocellular / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D018450:Disease Progression; D015972:Gene Expression Regulation, Neoplastic; D007150:Immunohistochemistry; D008114:Liver Neoplasms, Experimental / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D012334:RNA, Neoplasm / Q000235:genetics*; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction; D051176:beta Catenin / Q000235:genetics* / Q000378:metabolism
D012334:RNA, Neoplasm; D051176:beta Catenin