title: Livin is associated with the invasive and oncogenic phenotypes of human hepatocellular carcinoma cells.
abstract: OBJECTIVE
  Livin, a member of the inhibitors of apoptosis proteins, is expressed in variable cancers, and its expression is considered a poor prognostic marker. The aims of this study were to observe the effect of Livin on the behaviors of hepatocellular carcinoma (HCC) cells and to evaluate its expression in HCC tissues and its relation to prognosis.
  
  
  METHODS
  The biological effects of Livin on tumor cell behavior were investigated using siRNA in HepG2 and Chang cells. Migration, invasion and proliferation assays were performed. Flow cytometric analyses and western blotting were used to evaluate the impact of Livin on apoptosis and the cell cycle. In addition, western blotting and immunohistochemistry were used to investigate Livin expression in HCC tissues.
  
  
  RESULTS
  Livin knockdown suppressed tumor cell migration, invasion and proliferation in HCC cells, and increased the proportion of apoptotic cells as compared with scrambled siRNA-transfected HCC cells. Furthermore, Livin knockdown resulted in the activation of caspases and increased apoptosis. In addition, Livin knockdown modulated cell cycle regulatory protein levels such as decrease of cyclins and cyclin-dependent kinase (CDK) level, and increase of CDK inhibitor (CDKI) level in HCC cells. The Livin protein level was significantly elevated in HCC tissues as compared with normal hepatic tissues. However, Livin expression was not found to be associated with clinicopathological parameters, which included patient survival.
  
  
  CONCLUSIONS
  These results suggest that Livin is associated with invasive and oncogenic phenotypes of human HCC cells.
authors.affiliation: Department of Internal Medicine, Chonnam National University Medical School, Gwangju, Korea.
authors.forename: Sung-Bum
authors.initials: SB
authors.lastname: Cho
authors.forename: Wan-Sik
authors.initials: WS
authors.lastname: Lee
authors.forename: Young-Lan
authors.initials: YL
authors.lastname: Park
authors.forename: Nuri
authors.initials: N
authors.lastname: Kim
authors.forename: Hyung-Hoon
authors.initials: HH
authors.lastname: Oh
authors.forename: Mi-Young
authors.initials: MY
authors.lastname: Kim
authors.forename: Chan-Young
authors.initials: CY
authors.lastname: Oak
authors.forename: Cho-Yun
authors.initials: CY
authors.lastname: Chung
authors.forename: Hyung-Chul
authors.initials: HC
authors.lastname: Park
authors.forename: Jong-Sun
authors.initials: JS
authors.lastname: Kim
authors.forename: Dae-Seong
authors.initials: DS
authors.lastname: Myung
authors.forename: Sang-Hoon
authors.initials: SH
authors.lastname: Kim
authors.forename: Kyung-Hwa
authors.initials: KH
authors.lastname: Lee
authors.forename: Sung-Kyu
authors.initials: SK
authors.lastname: Choi
authors.forename: Young-Eun
authors.initials: YE
authors.lastname: Joo
keywords: Livin; apoptosis; hepatocellular carcinoma; tumor progression