title: TRAIL-Mediated Apoptosis in Human Liver Chang Cells.
abstract: OBJECTIVE
  Tumor necrosis factor (TNF)-related apoptosis inducing ligand (TRAIL)/APO-2L is a member of the TNF family that can kill a wide variety of tumor cells, but not normal cells. This study was designed to investigate the down stream target proteins in TRAIL-mediated apoptosis of human liver, Chang cells.
  
  
  METHODS
  The expressions of DR4/DR5 in hepatoma cells, including Chang, HepG2 and Hep3B cells, were determined by RT-PCR. Cell viability was measured by MTT assay and apoptosis was assessed by DNA fragmentation assay. The catalytic activity of caspase- family proteases, including caspase-3 and -9, was tested by using fluorogenic biosubstrates. Expression of apoptotic mediators, including procaspase-3 and PARP proteins, was measured by Western blotting. The expression profile of proteins in Chang cells by using two-dimensional (2-D) gel electrophoresis and MALDI-TOF.
  
  
  RESULTS
  The results demonstrated that TRAIL (100 ng/ml) induced the apoptotic death of Chang cells, as characterized by the ladder-pattern fragmentation of genomic DNA. TRAIL increased the enzymatic activity of caspase- 3, corresponding to the time of appearance of cleaved PARP and caspase-9. In 2-D gel electrophoresis and MALDI- TOF analysis, the comparison of control versus apoptotic cells in the protein expressions revealed that signal intensity of 7 spots were decreased, whereas 6 spots were increased among 300 spots. These spots were resolved and identified as a protein information by MALDI-TOF.
  
  
  CONCLUSIONS
  We suggested that TRAIL induces the apoptotic death of Chang cells via proteome alterations inducing caspase cascade.
authors.forename: Channy
authors.initials: C
authors.lastname: Park
authors.forename: Sung Wook
authors.initials: SW
authors.lastname: Hong
authors.forename: Sung Ho
authors.initials: SH
authors.lastname: Jin
authors.forename: Nam Song
authors.initials: NS
authors.lastname: Kim
authors.forename: Kyung Ho
authors.initials: KH
authors.lastname: Cho
authors.forename: Jin Ho
authors.initials: JH
authors.lastname: Cheon
authors.forename: Jae Yeon
authors.initials: JY
authors.lastname: Ahn
authors.forename: Jung Ku
authors.initials: JK
authors.lastname: Yang
authors.forename: Raekil
authors.initials: R
authors.lastname: Park
keywords: 2-D; Apoptosis; Caspase; Hepatoma; Tumor necrosis factor