The influence of heparin on the apoptosis and proliferation for K562 cells induced by vincristine

Abstract

Objective To investigate the effect of heparin on the apoptosis and proliferation of human myeloid leukemia cell line K562 induced by vincristine.Methods K562 cells were pretreated by heparin for 1h,then cultured with 0.05 mg/L vincristine in 37℃ 5% CO2 for 24 h.Apoptosis of KS62 cells was evaluated by Hoechst 33342 staining,flow cytometer and DNA agarose gel electrophoresis after culture for 24 hours.The effect of heparin on KS62 cell proliferation and toxicitv was determined by Trypan blue staining and MTT assay.Results In the apeptosis induced group,the apeptosis rate was 40.10% dected by Hoechst 33342 fluorescence staining.The hepafin in different concentrations was found to be able to inhibit the apoptosis of K562 cells triggered by vincristine and the apoptosis rate was 32.47%,29.7%,25.5%,19.53% in the heparin groups of 25,50,100,200 U/ml,respectively.The apeptosis rate was significantly lower in the apeptosis induced group than in the heparin groups of 25,50,100,200 U/ml(P＜0.05).The typical DNA ladder could be found in the apoptosis-induced group,and the DNA ladder gradually disappeared along with the increase of heparin(5～200 U/ml).The sub-G1 peak of K562 cells could be found in the induced group by FACS and the apoptosis rate was 21.61%.In the heparin groups of 25,50,100,200 U/ml,the sub-G1 Peak of K562 cells gradually dropped and the apoptosis rate was 13.64%,11.75%,8.59%,6.03%(P＜0.05),respectively.After K562 cells were incubated with different hepafin concentrations(5～200 U/ml)for 24 hours,there was no difference compared with the normal control group in both the total live cell numbers and the cell proliferation rate measured by trypan blue staining and MTT assay(P＞0.05).Conclusion The results suggested that heparin had no influence on KS62 cell toxicity and proliferation,but may inhibit the apoptosis of KS62 cells induced by vincristine. Key words: Apoptosis; K562 cell; Heparin; Vincristine