WWOX induces apoptosis and inhibits proliferation of human hepatoma cell line SMMC-7721.
OBJECTIVE
To investigate the effects of the WWOX gene on the human hepatic carcinoma cell line SMMC-7721.


METHODS
Full-length WWOX cDNA was amplified from normal human liver tissues. Full-length cDNA was subcloned into pEGFP-N1, a eukaryotic expression vector. After introduction of the WWOX gene into cancer cells using liposomes, the WWOX protein level in the cells was detected through Western blotting. Cell growth rates were assessed by methyl thiazolyl tetrazolium (MTT) and colony formation assays. Cell cycle progression and cell apoptosis were measured by flow cytometry. The phosphorylated protein kinase B (AKT) and activated fragments of caspase-9 and caspase-3 were examined by Western blotting analysis.


RESULTS
WWOX significantly inhibited cell proliferation, as evaluated by the MTT and colony formation assays. Cells transfected with WWOX showed significantly higher apoptosis ratios when compared with cells transfected with a mock plasmid, and overexpression of WWOX delayed cell cycle progression from G1 to S phase, as measured by flow cytometry. An increase in apoptosis was also indicated by a remarkable activation of caspase-9 and caspase-3 and a dephosphorylation of AKT (Thr308 and Ser473) measured with Western blotting analysis.


CONCLUSIONS
Overexpression of WWOX induces apoptosis and inhibits proliferation of the human hepatic carcinoma cell line SMMC-7721.
Department of General Surgery, Jiang Yuan Hospital affiliated to Jiangsu Institute of Nuclear Medicine, Wuxi 214063, Jiangsu Province, China. hubenshun2008@yahoo.com.cn
Ben-Shun
BS
Hu
Jing-Wang
JW
Tan
Guo-Hua
GH
Zhu
Dan-Feng
DF
Wang
Xian
X
Zhou
Zhi-Qiang
ZQ
Sun
D017209:Apoptosis / Q000235:genetics*; D006528:Carcinoma, Hepatocellular / Q000235:genetics / Q000378:metabolism*; D020170:Caspase 1 / Q000378:metabolism; D053453:Caspase 9 / Q000378:metabolism; D059447:Cell Cycle Checkpoints; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D006801:Humans; D010088:Oxidoreductases / Q000235:genetics / Q000378:metabolism*; D025521:Tumor Suppressor Proteins / Q000235:genetics / Q000378:metabolism*; D000074584:WW Domain-Containing Oxidoreductase
D025521:Tumor Suppressor Proteins; D010088:Oxidoreductases; D000074584:WW Domain-Containing Oxidoreductase; C486071:WWOX protein, human; D053453:Caspase 9; D020170:Caspase 1