title: [Role of caspase-8 in TRAIL-induced apoptosis of neuroblastoma cell lines].
abstract: OBJECTIVE
  The aim of this study was to investigate whether the induction of caspase-8 by γ-interferon (IFNγ) renders neuroblastoma (NB) cells sensitive to tumor necrosis factor related apoptosis inducing ligand(TRAIL).
  
  
  METHODS
  Caspase-8 mRNA expression was determined by RT-PCR. The effects of IFNγ, TRAIL, IFNγ +TRAIL and caspase-8 inhibitor+ TRAIL on the growth and apoptosis of NB cells were detected with the methods of reduction rate of Alamar Blue assay and flow cytometry. The relative caspase-8 activity was measured with colorimetric assay.
  
  
  RESULTS
  Caspase-8 expression was detectable in CHP212 cells which were sensitive to TRAIL, with an increased expression after treatment with IFNγ. Caspase-8 was undetectable in SH-SY5Y(SY5Y) cells which were resistant to TRAIL, but an increased expression of caspase-8 mRNA was found after treatment with IFNγ. Moreover, TRAIL combined with IFNγ induced apoptosis in SY5Y cells. The relative caspase-8 activity of CHP212 cells increased with the prolonged TRAIL action time. The relative caspase-8 activity of SY5Y cells in the IFNγ+TRAIL group was significantly higher than those of the control, IFNγ, TRAIL and inhibitor groups.
  
  
  CONCLUSIONS
  NB cells expressing caspase-8 are sensitive to TRAIL. TRAIL induces apoptosis in NB cells with an increase of relative caspase-8 activity.
authors.affiliation: Department of Blood Transfusion, Shengjing Hospital of China Medical University, Shenyang 110022, China. tonghaixia18@yahoo.com.cn
authors.forename: Hai-Xia
authors.initials: HX
authors.lastname: Tong
authors.forename: Chun-Wei
authors.initials: CW
authors.lastname: Lu
authors.forename: Li-Wei
authors.initials: LW
authors.lastname: Wang
authors.forename: Qiu-Shi
authors.initials: QS
authors.lastname: Wang
authors.forename: Ji-Hong
authors.initials: JH
authors.lastname: Zhang
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D053181:Caspase 8 / Q000502:physiology*; D045744:Cell Line, Tumor; D005434:Flow Cytometry; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology; D009447:Neuroblastoma / Q000188:drug therapy* / Q000473:pathology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D053221:TNF-Related Apoptosis-Inducing Ligand / Q000494:pharmacology*
chemical_list: D053221:TNF-Related Apoptosis-Inducing Ligand; D007371:Interferon-gamma; D053181:Caspase 8