Effects of Iron Chelators on Labile lron Pool and Apoptosis Related Genes Ex pression in K562 Cells

Objective To explore the effect of iron chelators on labile iron pool and expression of apoptosis associated genes in cells of K562, an erythroleukemia cell line.Methods K562 cells were incubated at 37 ℃ in RPMI 1640 containing 10% heat-inactived fetal bovine serum in an saturated humidity and 5% CO_2 incubator. K562 cells were incubated with different concentrations of desferro-(xamine(DFO)). The study groups were divided as following: DFO group, iron+DFO group and the control group. Following indices were detected which included apoptosis by flow cytometry (FCM) assay, expression of Rb, c-myc, bax mRNA by RT-PCR. The intracellular LIP was measured with a fluorimetric assay using the metalsensitive probe calcein-AM.Results 1. The viability of K562 cells incubated with different concentrations of DFO was lower than that of control group at 12 h,24 h and 48 h (P0.05). 2.The percentages of K562 cells incubated at different concentrations of DFO showed dose-time-dependent and much higher apoptosis than that of control group (P0.01). FCM assay showed that apoptosis of cells occurred mainly in the G1-period and S-period. 3. Expressions of bax, c-myc, Rb mRNA level in K562 cells were higher than those of the control group, when these cells were incubated with 50 μmol/L or 100 μmol/L DFO for 12 h,24 h and 48 h,respectively (P0.05).Conclusions Iron-deprivation could inhibit prolife-(ration) and induce apoptosis in leukemic cells. DFO inducing apoptosis of leukemic cells may be through up-regulated the expression of apoptosis-related genes.