title: [Photochemotherapy with psoralen and ultraviolet A induced apoptosis of NB4 cells and its effects on caspase-8 and caspase-8 protein expressions].
abstract: OBJECTIVE
  To study the regulatory effects of psoralen (PSO) plus ultraviolet A (UVA), which is PUVA, on cell apoptosis of human leukemia cell line NB4 and signal pathway of cell apoptosis.
  
  
  METHODS
  Human leukemia cell line NB4 was cultured in vitro. The NB4 cells were treated with PSO extracted from Chinese medicine psoralea fruits at different concentrations (0, 5, 10, 20 and 40 microL) plus UVA of wave length 360 nm at different irradiation time points (0 and 5 min). The apoptosis ratio was detected by flow cytometry (FCM). The ultrastructure changes were observed using transmission electron microscope (TEM). The expressions of Caspase-8 and Caspase-8 protein were detected by immunocytochemical method (ICC).
  
  
  RESULTS
  After treatment of PSO at different concentrations with a 0 and 5-min exposure of UVA, the apoptosis rate of NB4 cells increased dose-and time-dependently, and was up to peak after treatment of PSO at 40 microg/mL with 5-min exposure of UVA. An interaction was shown between the two factors (P <0. 01). There were obvious morphological apoptosis of NB4 cells under TEM after treated with PUVA. The expressions of Caspase-3 and Caspase-8 protein were up-regulated by PSO, UVA, and PUVA, but the effects of PUVA on Caspase-3 protein were stronger than PSO and UVA at 12 h time-dependently (P <0.01).An interaction was shown between the concentration of PSO and time of UVA (P <0.01).
  
  
  CONCLUSIONS
  The optimal combination of PUVA was PSO in 40 microg/mL and 5-min exposure of UVA. PUVA could induce the apoptosis of NB4 cells and in vitro activate Caspase-3 and Caspase-8 genes.
authors.affiliation: The Graduate School of the General Hospital of PLA, Beijing 100853 , China.
authors.forename: Shu-Jun
authors.initials: SJ
authors.lastname: Sun
authors.forename: Wei-jie
authors.initials: WJ
authors.lastname: Zhao
authors.forename: Yang
authors.initials: Y
authors.lastname: Xiang
authors.forename: Nan-Nan
authors.initials: NN
authors.lastname: Chen
authors.forename: Feng
authors.initials: F
authors.lastname: Sun
authors.forename: Xiao-Hui
authors.initials: XH
authors.lastname: Chang
authors.forename: Yu-Bin
authors.initials: YB
authors.lastname: Cheng
authors.forename: Shi-lin
authors.initials: SL
authors.lastname: Huang
mesh_terms: D017209:Apoptosis / Q000187:drug effects / Q000528:radiation effects; D053148:Caspase 3 / Q000378:metabolism; D053181:Caspase 8 / Q000378:metabolism; D045744:Cell Line, Tumor; D005363:Ficusin / Q000494:pharmacology* / Q000627:therapeutic use; D006801:Humans; D010778:Photochemotherapy / Q000379:methods; D014466:Ultraviolet Rays
chemical_list: C505407:CASP3 protein, human; C505530:CASP8 protein, human; D053148:Caspase 3; D053181:Caspase 8; D005363:Ficusin