Apoptotic sensitivity to irradiation increased after transfection of chk1 antisense chain to HL-60 cell line

Abstract

The HL-60 cells were transfected with chk1 antisense and sense chain, and 24 h later subjected to irradiation. Twenty-four h after irradiation, the changes in the chk1 protein expression was assayed by Western blot, and the cell cycles and apoptosis rate detected by FCM. The irradiated apoptosis sensitivity was increased by antisense blocking of chk1 gene in HL-60 cell line with the apoptosis rate being 26.31%, significantly higher than that by the sense blocking (10.34%, 0.025<P<0.05). In HL-60 cells transfected with chk1 antisense chain, the G₂/M phase arrest was attenuated and the cells in G₂/M phase were accounted for 38.42%, significantly lower than those of the cells transfected with chk1 sense chain (54.64%, 0.005<P<0.01). It was concluded that antisense blocking of chk1 gene could increase the apoptosis sensitivity to irradiation.

Keywords

antisense oligonucleotide / chk1 gene / HL-60 cell line / radiation sensitivity

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