[The relationship between p120ctn translocation and malignant features of hepatocellular carcinoma].
OBJECTIVE
To investigate the effect of catenin p120 (p120ctn) translocation on the malignant features of hepatocellular carcinoma and its interrelation with beta-catenin in E-cadherin-mediated cell signaling.


METHODS
Expression and translocation of p120ctn, tyrosine phosphorylation, and its binding capacity to E-cadherin were detected by DNA transfection, immunoblotting and immunoprecipitation. Cellular localization of p120ctn and beta-catenin was detected by immunofluorescent microscopy. Cell adhesion, cell migration and cell proliferation were also studied.


RESULTS
Expression of p120ctn increased after cells transfected with p120ctn isoform 3A, and it was located mainly at cell-cell contact region. Its binding to E-cadherin was enhanced. After EGF stimulation, tyrosine phosphorylation of p120ctn was increased, membrane expression of p120ctn and beta-catenin was decreased while cytosol expression was increased. It was translocated into the nucleus, cell adhesiveness was increased but mobility decreased. With over-expression of p120ctn, beta-catenin was recruited by nucleus export. Cell proliferation was reduced but it was increased after EGF treatment.


CONCLUSIONS
p120tn plays an important role in cell adhesion, migration and proliferation of hepatocellular carcinoma, and its tyrosine phosphorylation might contribute to this mechanism. There might be a competitive relationship between p120ctn and beta-catenin.
Huang
Hua-yi
HY
Department of Central Laboratory, Guangxi Nationalities Hospital, Nanning 530001, China. huayih@yahoo.com
Nong
Chao-zan
CZ
He
Wei-sheng
WS
Guo
Ling-xiao
LX
Nong
Shao-yun
SY
Pan
Li-li
LL
Zha
Xi-liang
XL
D015820:Cadherins / Q000378:metabolism*; D006528:Carcinoma, Hepatocellular / Q000378:metabolism / Q000473:pathology*; D051177:Catenins; D002448:Cell Adhesion; D015815:Cell Adhesion Molecules / Q000378:metabolism*; D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000378:metabolism; D002465:Cell Movement; D002467:Cell Nucleus / Q000378:metabolism; D049109:Cell Proliferation; D003598:Cytoskeletal Proteins / Q000378:metabolism*; D003600:Cytosol / Q000378:metabolism; D004815:Epidermal Growth Factor / Q000494:pharmacology*; D006801:Humans; D008113:Liver Neoplasms / Q000378:metabolism / Q000473:pathology*; D010750:Phosphoproteins / Q000378:metabolism*; D010766:Phosphorylation; D021381:Protein Transport; D015534:Trans-Activators / Q000378:metabolism*; D014443:Tyrosine / Q000378:metabolism; D051176:beta Catenin; D000095002:Delta Catenin
C495270:CTNNB1 protein, human; D015820:Cadherins; D051177:Catenins; D015815:Cell Adhesion Molecules; D003598:Cytoskeletal Proteins; D010750:Phosphoproteins; D015534:Trans-Activators; D051176:beta Catenin; D014443:Tyrosine; D004815:Epidermal Growth Factor; D000095002:Delta Catenin; C000722347:CTNND1 protein, human