title: ESC reverses epithelial mesenchymal transition induced by transforming growth factor-β via inhibition of Smad signal pathway in HepG2 liver cancer cells.
abstract: BACKGROUND
  Epithelial mesenchymal transition (EMT) mediated by TGF-β pays an important role in malignant tumor acquired abilities of migration and invasion. Our previous study showed that the extract of Stellera chamaejasme L. (ESC) was against proliferation of a variety of tumor cells, but there were no studies in the effects of ESC on EMT in tumor cells. In this study, TGF-β was adopted to induce EMT in HepG2 cells and the influence of ESC on EMT was observed.
  
  
  METHODS
  MTT assay was used to observe the cell viability. Wound healing assay and transwell assay were used to observe the migration and invasion activities. Western blot and immunofluorescence methods were used to observe the expression of proteins.
  
  
  RESULTS
  We found that HepG2 cells induced by TGF-β showed mesenchymal morphology, down-regulation of epithelial marker E-cadherin and up-regulation of mesenchymal marker Vimentin, indicating that TGF-β could mediate epithelial mesenchymal induction in HepG2 cells. ESC could reverse the mesenchymal morphology and regulate expressions of marker proteins in HepG2 induced by TGF-β and significantly inhibit TGF-β induced HepG2 cell migration and invasion. We further found that ESC could also significantly depress Smad2 phosphorylation and nuclear translocation, and ESC had coordination with SB432542, a specific inhibitor of TβRI kinases.
  
  
  CONCLUSIONS
  These results suggested that the ESC could reverse epithelial mesenchymal transition induced by TGF-β via inhibition Smad2 signaling pathway.
authors.affiliation: Beijing Institute of Hepatology and Beijing YouAn Hospital, Capital Medical University, No 8 Xi Tou Tiao, You An Men Wai, Feng Tai Qu, Beijing, 100069 China.
authors.forename: Xiao-Ni
authors.initials: XN
authors.lastname: Liu
authors.affiliation: Beijing Institute of Hepatology and Beijing YouAn Hospital, Capital Medical University, No 8 Xi Tou Tiao, You An Men Wai, Feng Tai Qu, Beijing, 100069 China.
authors.forename: Shuang
authors.initials: S
authors.lastname: Wang
authors.affiliation: Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, No 16 Nan Xiao Jie, Dong Zhi Men Nei, Dong Cheng Qu, Beijing, 100700 China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Yang
authors.affiliation: Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, No 16 Nan Xiao Jie, Dong Zhi Men Nei, Dong Cheng Qu, Beijing, 100700 China.
authors.forename: Ya-Jie
authors.initials: YJ
authors.lastname: Wang
authors.affiliation: Beijing Institute of Hepatology and Beijing YouAn Hospital, Capital Medical University, No 8 Xi Tou Tiao, You An Men Wai, Feng Tai Qu, Beijing, 100069 China.
authors.forename: De-Xi
authors.initials: DX
authors.lastname: Chen
authors.affiliation: Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, No 16 Nan Xiao Jie, Dong Zhi Men Nei, Dong Cheng Qu, Beijing, 100700 China.
authors.forename: Xiao-Xin
authors.initials: XX
authors.lastname: Zhu
keywords: Epithelial mesenchymal transition; Hepatocellular carcinoma; Metastasis; Smad signaling pathway; Stellera chamaejasme L.; Transforming growth factor