Objective:To study the effect of transcription factor FOXO3a on acute myeloblastic leukemia HL60 cell line proliferation

apoptosis and the possible molecular mechanism.Methods: The FOXO3a expression plasmid pcDNA3.1-FOXO3a and the no-load control plasmid pcDNA3.1 were separately transfected to HL60 cells mediated by cationic lipid body.The FOXO3a stable expression cell line was screened with G418.HL60 cell proliferation was assayed by Trypan blue exclusion staining and MTT.Cell cycle and apoptosis were analyzed by flow cytometry.The expressions of Bim and bcl-2 genes were detected by RT-PCR and Western blot method.Results: The stable cell lines HL60/FOXO3a cells were screened

which significantly inhibited the growth and proliferation ability of HL60 cells compared with the empty vector transfection group(HL60/empty) and untreated control group(HL60/untreated) cells

and were accompanied with G1 phase block and apoptotic cell increase.The gene FOXO3a significantly up-regulated Bim gene mRNA and protein expression

while inhibited the bcl-2 gene mRNA and protein expression.Conclusion: Transcription factor FOXO3a could inhibit HL60 cell growth and proliferation

and induce apoptosis.Its possible mechanism may be involved in the regulation of apoptosis-related genes and prevention of cell cycle progression.