摘 要 目的: 研究去甲基化制剂5-氮-2′-脱氧胞苷（5-Aza-2′-deoxycytidine,5-Aza-CdR）和组蛋白去乙酰化酶抑制剂曲古抑菌素A（trichostatin A,TSA）在体内外对子宫内膜腺癌Ishikawa细胞的抑制作用。方法:以5-Aza-CdR和TSA单独或联合作用Ishikawa细胞，锥虫蓝拒染法观察药物对肿瘤细胞生长的影响，流式细胞仪检测细胞凋亡和分析细胞周期，Western blotting检测肿瘤细胞凋亡信号通路中caspase- 8活化及多聚ADP核糖聚合酶（PARP）裂解情况。建立裸鼠Ishikawa细胞移植瘤模型，观察两抑制剂作用下的移植成瘤率、肿瘤的体积和重量。结果: 5-Aza-CdR和 TSA对Ishikawa细胞增殖有明显的抑制作用，呈剂量、时间依赖性；两制剂联合作用时抑制作用更强（P<0.05）。5-Aza-CdR或TSA均可诱导细胞凋亡，联合作用后细胞的凋亡率更高（P<0.05）; 5-Aza-CdR和TSA联合应用使细胞发生明显的G1期阻滞；5-Aza-CdR和 TSA诱导了caspase-8活化及PARP裂解。荷瘤小鼠予5-Aza-CdR和 TSA治疗后移植瘤生长速度减慢，移植瘤体积和重量明显减少。结论: 5-Aza-CdR与TSA能抑制Ishikawa肿瘤细胞增殖、诱导细胞凋亡，两者联合作用时强度明显增加；其机制与两制剂诱导caspase-8活化及PARP裂解有关。

Abstract Objective: To study the inhibitory effect of demethylating agent 5Aza2′deoxycytidine（5AzaCdR）and trichostatin A (TSA) against human endometrial cancer cell line Ishikawa in vitro. Methods: Ishikawa cells were treated with 5AzaCdR, TSA or a combination of both and the growth curves of cells in each group were obtained by trypanblue exclusion assay and cell counting. The cell apoptosis was examined by Annexin V, cell cycle by flow cytometry, and cleavage of poly ADPribose polymerase (PARP) and activation of caspase8 by Western blotting. The effect of the 2 inhibitors on the survival rates of transplanted tumors, tumor sizes and weights were studied in mouse transplantation model of Ishikawa cells. Results: 5AzaCdR and TSA inhibited the growth of Ishikawa cells in a dose and timedependent manner. 5AzaCdR combined with TSA resulted in greater growth inhibition than they were used alone（P<0.05）. 5AzaCdR and TSA both induced apoptosis of Ishikawa cells, and a combination of the two caused higher apoptosis rate（P<0.05）. 5AzaCdR combined with TSA also induced the G1 phase arrest of Ishikawa cells. Caspase8 activation and cleavage of PARP were confirmed by Western blotting. 5AzaCdR and TSA inhibited the growth of transplanted tumors and reduced the volume and weight of tumors. Conclusion: 5AzaCdR and TSA can inhibit the growth of Ishikawa cells and induce their apoptosis, and combination of both has more potent effect, which might be related to the activation of caspase8 and the cleavage of PARP.

山东省引进国外智力项目基金资助(No.20083700340)