Comprehensive analysis of the independent effect of twist and snail in promoting metastasis of hepatocellular carcinoma.
The epithelial-mesenchymal transition (EMT) is critical for induction of invasiveness and metastasis of human cancers. In this study we investigated the expression profiles of the EMT markers, the relationship between EMT markers and patient/tumor/viral factors, and the interplay between major EMT regulators in human hepatocellular carcinoma (HCC). Reduced E-cadherin and nonmembranous beta-catenin expression, the hallmarks of EMT, were shown in 60.2% and 51.5% of primary HCC samples, respectively. Overexpression of Snail, Twist, or Slug, the major regulators of EMT, was identified in 56.9%, 43.1%, and 51.4% of primary HCCs, respectively. Statistical analysis determined that Snail and Twist, but not Slug, are major EMT inducers in HCC: overexpression of Snail and/or Twist correlated with down-regulation of E-cadherin, nonmembranous expression of beta-catenin, and a worse prognosis. In contrast, there were no such significant differences in samples that overexpressed Slug. Coexpression of Snail and Twist correlated with the worst prognosis of HCC. Hepatitis C-associated HCC was significantly correlated with Twist overexpression. HCC cell lines with increased Snail and Twist expression (e.g., Mahlavu) exhibited a greater capacity for invasiveness/metastasis than cells with low endogenous Twist/Snail expression (e.g., Huh-7). Overexpression of Snail or/and Twist in Huh-7 induced EMT and invasiveness/metastasis, whereas knockdown of Twist or Snail in Mahlavu reversed EMT and inhibited invasiveness/metastasis. Twist and Snail were independently regulated, but exerted an additive inhibitory effect to suppress E-cadherin transcription.


CONCLUSIONS
Our study provides a comprehensive profile of EMT markers in HCC, and the independent and collaborative effects of Snail and Twist on HCC metastasis were confirmed through different assays.
Yang
Muh-Hwa
MH
Institutes of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan.
Chen
Chih-Li
CL
Chau
Gar-Yang
GY
Chiou
Shih-Hwa
SH
Su
Chien-Wei
CW
Chou
Teh-Ying
TY
Peng
Wei-Li
WL
Wu
Jaw-Ching
JC
D000328:Adult; D000368:Aged; D000818:Animals; D014408:Biomarkers, Tumor / Q000378:metabolism*; D015820:Cadherins / Q000378:metabolism; D006528:Carcinoma, Hepatocellular / Q000378:metabolism / Q000473:pathology*; D002454:Cell Differentiation / Q000502:physiology; D045744:Cell Line, Tumor; D004847:Epithelial Cells / Q000378:metabolism / Q000473:pathology; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000378:metabolism / Q000473:pathology*; D008297:Male; D008648:Mesoderm / Q000378:metabolism / Q000473:pathology; D051379:Mice; D008819:Mice, Nude; D008875:Middle Aged; D009362:Neoplasm Metastasis / Q000473:pathology*; D009687:Nuclear Proteins / Q000378:metabolism*; D012189:Retrospective Studies; D000071250:Snail Family Transcription Factors; D014157:Transcription Factors / Q000378:metabolism*; D016212:Transforming Growth Factor beta / Q000378:metabolism; D014183:Transplantation, Heterologous; D051879:Twist-Related Protein 1 / Q000378:metabolism*; D014746:Vimentin / Q000378:metabolism; D051176:beta Catenin / Q000378:metabolism; D051185:gamma Catenin / Q000378:metabolism
D014408:Biomarkers, Tumor; D015820:Cadherins; D009687:Nuclear Proteins; C000604407:SNAI1 protein, human; C000604449:Snai2 protein, mouse; D000071250:Snail Family Transcription Factors; C103173:TWIST1 protein, human; D014157:Transcription Factors; D016212:Transforming Growth Factor beta; D051879:Twist-Related Protein 1; D014746:Vimentin; D051176:beta Catenin; D051185:gamma Catenin