title: [Deferoxamine induces apoptosis of K562 cells].
abstract: OBJECTIVE
  To study the molecular mechanism of apoptosis of leukemic cells (K562 cells) induced by iron chelating agent deferoxamine (DFO).
  
  
  METHODS
  The exponentially growing K562 cells were used (1×10(6)/mL) in this study. The K562 cells were treated with different concentrations of DFO (10, 50 and 100 mmol/L), DFO+FeCl3 (10 μmol/L each) or normal saline (blank control). The cellular labile iron pool was measured with a fluorimetric assay using the metalsensitive probe calcein-AM. The viable count and cell viability were determined by typanblue assay. Cell apoptosis was determined by morphological study and flow cytometry assay. Caspase-3 activity in K562 cells was detected by colorimetry.
  
  
  RESULTS
  After DFO treatment, the cellular labile iron pool and the viability of K562 cells were reduced and the cell apoptosis increased in a time- and dose-dependent manner compared with the blank control group. The apoptosis rate of K562 cells in the DFO+FeCl3 treatment group was not significantly different from that in the blank control group. The caspase-3 activity in K562 cells increased significantly 24 hrs after 50 and 100 μmmol DFO treatment when compared with the blank control group (P<0.01). There was a negative correlation between cellular labile iron pool and caspase-3 activity of K562 cells (r=-0.894, P<0.05).
  
  
  CONCLUSIONS
  DFO induces apoptosis of leukemic cells possibly through decreasing cellular labile iron pool and increasing caspase-3 activity of the cells.
authors.affiliation: Department of Hematology, Zhengzhou Children's Hospital, Zhengzhou, China.
authors.forename: Guo-Cun
authors.initials: GC
authors.lastname: Jia
authors.forename: You-Cai
authors.initials: YC
authors.lastname: Tang
authors.forename: Feng-Yi
authors.initials: FY
authors.lastname: Li
authors.forename: Qing-Kui
authors.initials: QK
authors.lastname: Liao
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D053148:Caspase 3 / Q000378:metabolism; D003676:Deferoxamine / Q000494:pharmacology*; D005434:Flow Cytometry; D006801:Humans; D007502:Iron Chelating Agents / Q000494:pharmacology*; D020014:K562 Cells
chemical_list: D007502:Iron Chelating Agents; D053148:Caspase 3; D003676:Deferoxamine