ABSTRACT
This study was purposed to investigate the effects of siRNA targeting c-myc on apoptosis induction, proliferation in inhibition as well as c-myc protein and mRNA expression in human myeloid leukemia cell line HL-60 cells. C-myc siRNA synthesized in vitro was transfected into HL-60 cells by liposome. Changes of cell morphology were observed. Growth inhibition was detected by MTT assay and colony formation assay, and cell apoptosis was determined by DNA ladder. The expressions of c-myc mRNA and protein were detected by RT-PCR and Western-blot respectively. The results indicated that c-myc siRNA remarkably inhibited the cell proliferation, with an IC(50) value of 150 nmol/L. Data of DNA ladder showed that HL-60 cells apoptosis could be efficiently induced by c-myc siRNA, the apoptosis rate positively correlated with the time duration of treatment with drugs. The c-myc mRNA and protein expressions on HL-60 cells decreased after treatment with c-myc siRNA, which negatively correlated with time duration of treatment. It is concluded that c-myc siRNA can efficiently induce growth inhibition, decrease the expressions of c-myc mRNA and protein, and induce apoptosis in HL-60 cells.