Effect of SALL4 on radiosensitivity of leukemia cell line HL-60 / 中华放射肿瘤学杂志

ABSTRACT

Objective To evaluate the effect of down-regulating SALL4 on the radiosensitivity of leukemia cells,aiming to provide new ideas for improving radiosensitivity of leukemia patients.Methods Human acute myeloid leukemia cell line HL-60 infected with shRNA SALL4 and shRNA control lentivirus was classified into the Lv-shSALL4 group and Lv-shNC group.The levels of SALL4 mRNA and protein in cells were detected by RT-PCR and Western blot.The infected cells treated with 8 Gy dose irradiation were assigned into the Lv-shSALL4 + radiation and Lv-shNC+radiation groups.The cell apoptosis was detected by flow cytometry.The levels of cleaved Caspase-3,cleaved Caspase-9 and Bax proteins in cells were determined by Western blot.The cells in the Lv-shSALL4 and Lv-shNC groups were exposed to 0,2,4,6 and 8 Gy irradiation.The radiosensitivity ratio was determined by cell clone test.Results The level of SALL4 in the Lv-shSALL4 group was significantly lower than that in the Lv-shNC group (P＜0.05).The cell apoptosis rate was significantly increased,the levels of cleaved Caspase-3,cleaved Caspase-9 and Bax proteins were remarkably up-regulated in cells compared with those in the Lv-shNC group (all P＜ 0.05).The cell proliferation ability in the Lv-shSALL4 + radiation was significantly reduced,the cell apoptosis rate was considerably increased,the levels of cleaved Caspase-3,cleaved Caspase-9 and Bax proteins were significantly up-regulated compared with those in the Lv-shSALL4 and Lv-shNC+ radiation groups (all P＜0.05).The cell radiosensitization ratio in the Lv-shSALL4 group was 1.323.Conclusion Down-regulating SALL4 can increase the radiosensitivity of leukemic cells,inhibit the cell proliferation and induce the apoptosis of leukemic cells.