RESUMO
Objective: To study the effects of vitamin E and selenium on apoptosis and c-Myc expression in human leukemia cells. Methods: DNA gel electrophoresis and Northern blotting hybridization were used to detect the apoptosis and the expression of c-Myc gene, respectively. Human leukemia cell line HL-60 and K562 were cultured in vitro. Results: The apoptosis of HL-60 and K562 cells were induced after being exposed to vitamin E (100 ?mol/L) and selenium (8 ?mol/L) for 24 hours, respectively. In HL-60 cell line, c-Myc mRNA was down-regulated significantly by vitamin E(100 ?mol/L),but not selenium(8 ?mol/L).In contrast, the expression of c-Myc gene was repressed by selenium(8 ?mol/L) and not by vitamin E(100 ?mol/L) in K562 cell. Conclusion: Our observations suggest that c-Myc down-regulation and induction of apoptosis by selenium and vitamin E are important pathways in repressing leukemia cell proliferation.The results suggest there are different mechanisms of repressing leukemia cell proliferation for selenium and vitamin E.