曲古菌素A诱导前列腺癌DU-145细胞有丝分裂的灾变

Trichostatin A induces mitotic catastrophe of prostate cancer DU145 cells

目的:研究组蛋白去乙酰化酶抑制剂(histone deacetylase inhibitor,HDACi)曲古菌素(trichostatina A,TSA)对前列腺癌DU145细胞有丝分裂的影响,探讨HDACi杀伤肿瘤细胞的新机制。方法:将前列腺癌DC-145细胞分成不加药对照组和不同剂量(100、200、300、400nmol/L)TSA加药组,药物作用一定时间后,MTT法检测TSA对DU145细胞的杀伤效应,瑞氏-姬姆萨染色观察细胞形态的变化,流式细胞术分析细胞周期的改变,免疫荧光染色观察DU145细胞异常的有丝分裂现象,Western blotting检测TSA处理对DU145细胞某些调控蛋白表达的影响。结果:TSA处理诱导DU145细胞发生有丝分裂,TSA处理24h后多核细胞数目由0.24%增加至1.21%。细胞周期计数结果显示,TSA处理后有丝分裂各期细胞比例发生明显改变,表现为有丝分裂前中期细胞所占比例增加,后末期细胞所占比例减少。免疫荧光染色显示,细胞出现多极纺锤体、染色体分离滞后等异常有丝分裂现象。TSA作用于DU145细胞后,能明显抑制Survivin蛋白的表达,增强细胞骨架蛋白Tubulin的乙酰化,并诱导P21蛋白高表达。结论:TSA能够诱使DU145细胞发生有丝分裂灾变,其机制可能与TSA降低Survivin蛋白的表达以及增强微管蛋白的乙酰化有关。

Objective： To investigate the effect of trichostatina A （ TSA）, a histone deacetylase inhibitor, on the mitosis of the prostate cancer cell line DU145 and to elucidate the possible mechanism of TSA anti-tumor activity. Methods： The inhibitory effects of TSA（ 100, 200, 300, and 400 nmol/L）on DU145 cell growth were determined by MTT assay. Wright-Giemsa staining was used to examine the morphological changes of cells. Cell cycle arrest was detected by flow cytometry assay. The abnormalities of mitosis were observed by immunofluorescence staining. Western blotting was used to examine the effect of TSA on expression of the some regulatory protein in DU145 cells. Results： TSA treatment induced mitotic catastrophe of DU145 cells, including morphological changes, cell cycle arrest at G0/G1 phase, and abnormalities of mitosis and cytokinesis forming multipolar spindle and lagging chromosome. After 24 h treatment with TSA, the multinuclear cells increased from 0.24% to 1.21%. The ratios of cells of prophase and metaphase were increased, while the ratios of anaphase and telophase were decreased. The results of Western blotting indicated that TSA treatment inhibited survivin protein expression, enhanced the acetylation of tubulin and increased the expression of P21 protein. Conclusion： Our data indicate that TSA can induce the mitotic catastrophe in the prostate cancer DU145 cells, possibly because TSA can decrease survivin level and enhance the acetylation of tubulin.