ABSTRACT
<p><b>OBJECTIVE</b>To explore the molecular mechanisms of G(2)/M checkpoint initiated by diallyl disulfide (DADS) in HL-60 cells.</p><p><b>METHODS</b>Cell viability was determined by MTT assay. Cell cycle was assayed by flow cytometry. The expression of phospho-p38, Cdc25B and Cdc2, and p38 mRNA were measured by Western blotting and RT-PCR, respectively.</p><p><b>RESULTS</b>After treatment with DADS at 5 - 160 micro mol/L for 0 - 72 h, the growth of HL-60 cells were suppressed in a concentration-dependent manner and the inhibitory effect of DADS (20 micro mol/L) was similar to that of ATRA (10 nmol/L) (P > 0.05). Incubation of HL-60 cells with DADS (20 micro mol/L) for 12 h could activate G(2)/M checkpoint and increase the expression of phospho-p38 MAPK, followed by the expression of phospho-Cdc25B and phospho-Cdc2 (P < 0.05). SB202190, a specific inhibitor of p38 MAPK, markedly blocked the phosphorylation of p38 MAPK, Cdc25B and Cdc2 (P < 0.05).</p><p><b>CONCLUSION</b>DADS could induce the G(2)/M arrest in HL-60 cells which may be involved in the activation of p38 MAP kinase.</p>