PTEN induces apoptosis and up-regulates p53 expression in HepG2 cells / 中华肝脏病杂志
Chinese Journal of Hepatology
; (12): 745-748, 2004.
Article
in Zh
| WPRIM
| ID: wpr-233674
Responsible library:
WPRO
ABSTRACT
<p><b>OBJECTIVE</b>To investigate the effects of tumor suppressor gene PTEN on apoptosis and protein expression of p53 in HepG2 cells, as well as to explore its mechanisms.</p><p><b>METHODS</b>HepG2 cells were transfected with GFP plasmids containing wild-type PTEN or G129E-PTEN and C124A-PTEN in vitro. Both the expression of wild-type p53 and the phosphorylation of protein kinase B (PKB/Akt) and focal adhesion kinase (FAK) were detected by Western blotting. Flow cytometry and confocal microscopy were used to analyze apoptosis of the transfected cells.</p><p><b>RESULTS</b>Compared with the control, the expression of phosphorylated FAK and phosphoylated Akt were down-regulated in HepG2 cells transfected with wild-type PTEN (-65%, -93%) and G129E-PTEN (-65%, -35%), whereas the apoptosis percentage increased to (19.8+/-1.2)% and (9.2+/-0.6)%, and p53 expression was up-regulated by 120% and 50%, respectively. However, in the cells transfected with C124A-PTEN, neither the phosphorylation of FAK and Akt nor the apoptosis percentage and p53 expression had changed.</p><p><b>CONCLUSION</b>PTEN can dephosphrylate FAK through its protein phosphatase activity, and suppress phosphorylation of Akt mainly through its lipid phosphatase activity. Consequently, it can induce apoptosis of HepG2 cells and up-regulate p53 expression.</p>
Full text:
1
Index:
WPRIM
Main subject:
Pathology
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Gene Expression Regulation, Neoplastic
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Up-Regulation
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Tumor Suppressor Protein p53
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Apoptosis
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Carcinoma, Hepatocellular
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PTEN Phosphohydrolase
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Genetics
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Liver Neoplasms
Limits:
Humans
Language:
Zh
Journal:
Chinese Journal of Hepatology
Year:
2004
Type:
Article