二烯丙基二硫诱导HL-60细胞G2/M期生长阻滞的分子机制研究

目的　探讨二烯丙基二硫 (DADS)诱导HL 6 0细胞G2 /M期细胞生长阻滞的分子机制。方法　用不同浓度的DADS处理HL 6 0细胞 ,分别作用 0 ,6 ,1 2 ,2 4 ,4 8h后用MTT法测定细胞增殖活性 ;用流式细胞术和有丝分裂指数测定细胞增殖周期 ;用Westernblot检测 p38丝裂原活化蛋白 (p38MAPK)及Cdc2 5B和Cdc2激酶的表达和磷酸化水平 ;用RT PCR检测p38MAPKmRNA的表达。结果　DADS抑制HL 6 0细胞增殖呈浓度依赖性 ,且DADS(2 0 μmol/L)与ATRA(1 0nmol/L)对HL 6 0细胞增殖活性影响相近 (P >0 .0 5 ) ;DADS 2 0 μmol/L作用HL 6 0细胞 1 2h后能引起G2 /M期细胞百分数增高并达到最大值 ,而此时有丝分裂指数明显下降 (P <0 .0 5 ) ;同时 ,磷酸化p38MAPK蛋白及p38MAPKmRNA的表达达到高峰 (P <0 .0 5 ) ,并引起Cdc2 5B和Cdc2磷酸化水平的相应变化。而p38特异性抑制剂SB2 0 2 1 90 (1 0 μmol/L)能阻断DADS对HL 6 0细胞增殖的抑制作用 (P <0 .0 5 )。结论　DADS能启动HL 6 0细胞G2 /M控制点 ,它的激活可能与磷酸化 p38MAPK的活化有关

The initiation of G2/M checkpoint by diallyl disulfide requires the activation of p38 MAP kinase in HL-60 cells

OBJECTIVE: To explore the molecular mechanisms of G(2)/M checkpoint initiated by diallyl disulfide (DADS) in HL-60 cells. METHODS: 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. RESULTS: 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). CONCLUSION: DADS could induce the G(2)/M arrest in HL-60 cells which may be involved in the activation of p38 MAP kinase.