title: Insufficient radiofrequency ablation promotes epithelial-mesenchymal transition of hepatocellular carcinoma cells through Akt and ERK signaling pathways.
abstract: BACKGROUND
  Residual tumor progression after insufficient radiofrequency ablation (RFA) has been recently reported. However, whether epithelial-mesenchymal transition (EMT), which is a key process that drives cancer metastasis, is involved in the tumor progression after insufficient RFA is not well understood.
  
  
  METHODS
  Human hepatocellular carcinoma (HCC) cell lines SMMC7721 and Huh7 were used. Insufficient RFA was simulated using a water bath (47°C 5 min, 10 min, 15 min, 20 min and 25 min gradually). MTT assay was used to evaluate the proliferation of HCC cells in vitro. Migration and invasion of HCC cells were determined by transwell assay. The molecular changes in HCC cells after insufficient RFA were evaluated by western blot. LY294002 and PD98059 were used to treat HCC cells. An ectopic nude mice model and a tail vein metastatic assay were used to evaluate the growth and metastatic potential of SMMC7721 cells in vivo after insufficient RFA.
  
  
  RESULTS
  SMMC7721 and Huh7 cells after insufficient RFA (named as SMMC7721-H and Huh7-H respectively) exhibited enhanced proliferation, migration and invasion (6.4% and 23.6%, 33.2% and 66.1%, and 44.1% and 57.4% increase respectively) in vitro. Molecular changes of EMT were observed in SMMC7721-H and Huh7-H cells. LY294002 and PD98059 inhibited the EMT of SMMC7721-H and Huh7-H cells. SMMC7721-H cells also exhibited larger tumor size (1440.8±250.3 mm3 versus 1048.56±227.6 mm3) and more lung metastasis (97.4% increase) than SMMC7721 cells in vivo. Higher expression of PCNA, N-cadherin and MMP-2 and MMP-9, was also observed in SMMC7721-H tumors.
  
  
  CONCLUSIONS
  Insufficient RFA could directly promote the invasiveness and metastasis of HCC cells. Insufficient RFA may promote the EMT of HCC cells through Akt and ERK signaling pathways.
authors.forename: Shuying
authors.initials: S
authors.lastname: Dong
authors.forename: Jian
authors.initials: J
authors.lastname: Kong
authors.forename: Fandong
authors.initials: F
authors.lastname: Kong
authors.forename: Jinge
authors.initials: J
authors.lastname: Kong
authors.forename: Jun
authors.initials: J
authors.lastname: Gao
authors.forename: Shan
authors.initials: S
authors.lastname: Ke
authors.forename: Shaohong
authors.initials: S
authors.lastname: Wang
authors.forename: Xuemei
authors.initials: X
authors.lastname: Ding
authors.affiliation: Department of Hepatobiliary Surgery, Beijing Chaoyang Hospital, Capital Medical University, Beijing, 100043, China. wb.sun@yahoo.com.cn.
authors.forename: Wenbing
authors.initials: W
authors.lastname: Sun
authors.forename: Lemin
authors.initials: L
authors.lastname: Zheng
mesh_terms: D000818:Animals; D006528:Carcinoma, Hepatocellular / Q000201:enzymology / Q000473:pathology / Q000628:therapy*; D017115:Catheter Ablation / Q000379:methods*; D045744:Cell Line, Tumor; D002867:Chromones / Q000494:pharmacology; D018450:Disease Progression; D058750:Epithelial-Mesenchymal Transition; D005419:Flavonoids / Q000494:pharmacology; D006801:Humans; D008113:Liver Neoplasms / Q000201:enzymology / Q000473:pathology / Q000628:therapy*; D020935:MAP Kinase Signaling System; D051379:Mice; D008819:Mice, Nude; D009025:Morpholines / Q000494:pharmacology; D009362:Neoplasm Metastasis; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*
chemical_list: D002867:Chromones; D005419:Flavonoids; D009025:Morpholines; C085911:2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one; D051057:Proto-Oncogene Proteins c-akt; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one