冬凌草甲素诱导胃癌SGC-7901细胞凋亡及机制

Apoptosis induction of human gastric cancer SGC-7901 cells by oridonin and its mechanism

目的探讨冬凌草甲素体外诱导胃癌SGC-7901细胞凋亡和细胞周期阻滞的作用及其机制。方法10～80μmol／L冬凌草甲素分别处理SGC-7901细胞后，CCK8法检测冬凌草甲素体外对SGC-7901细胞抑制生长的作用；用流式细胞仪分别观察冬凌草甲素诱导凋亡及细胞周期阻滞。Westernblot测定凋亡相关蛋白的表达。结果冬凌草甲素对SGC-7901细胞有明显的生长抑制作用，并随着药物浓度的增加（10～80μmol／L）而逐渐增强，呈浓度、时间依赖关系。此外，流式细胞术检测发现，冬凌草甲素浓度为0、10、40、60、80μmol／L，作用24h后，G2／M期细胞数分别是（9．90±1．17）％、（9．94±0．27）％、（11．76±0．16）％、（15．64±1．48）％和（22．59±1．01）％；而S期细胞比例分别为（31．79±1．03）％、（30．90±0．47）％、（29．25±0．80）％、（21．46±1．61）％、（18．81±0．61）％，冬凌草甲素能够使得SGC-7901细胞周期呈剂量依赖性阻滞于G2／M期；冬凌草甲素浓度为80μmol／L，作用12、24h后，凋亡率分别为（12．78±1．54）％、（20．62±2．39）％，明显高于对照组的（9．92±0．55）％，其能使SGC-7901细胞发生凋亡。随着冬凌草甲素作用时间延长，SGC-7901细胞的bcl-2蛋白表达逐渐减弱，前体Caspase-3被激活。结论冬凌草甲素能够诱导SGC-7901细胞产生凋亡，并使细胞周期阻滞在G2／M期。其凋亡机制可能与下调bcl-2蛋白表达及Caspase-3的激活相关。

Objective To investigate the in vitro cell cycle arrest and apoptosis inducing effects of oridonin on SGC-7901 cell lines and the action mechanisms. Methods After administration of 10-80 μmol/L oridonin for 24-120 h, the CCK8 method was used to investigate the inhibitory effect of oridonin on SGC-7901 cells. Cell apoptosis and cell cycle arrest were investigated by flow cytometry （FCM）. The expression of apoptosis related proteins was detected using Western blotting. Results Oridonin could significantly inhibit the growth of SGC-7901 cells in both time-dependent and dose-dependent manners. FCM revealed that after treatment with different concentrations of oridonin （0, 10, 40, 60, 80 μmol/L） for 24 h, the number of G2/M stage cells was （9. 90 ± 1.17）%, （9. 94 ±0. 27）%, （11.76 ±0. 16）%, （15. 64 ＋ 1.48）%, （22.59±1.01）%, and that of S stage cells was （31.79±1.03）%, （30.90±0.47）%, （29. 25 ± 0. 80） %, （21.46 ± 1.61 ） %, （ 18.81 ± 0. 61 ） % respectively. The apoptotic rate was （9. 92 ± 0. 56） %, （ 12. 78 ± 1.54 ） % and （ 20. 62 ± 2. 39 ） % respectively within 0, 12 and 24 h after treatment with 80 μmol/L oridonin. With the extension of oridonin treatment, the bel-2 protein expression in SGC- 7901 cells was gradually reduced, and pro-caspase 3 was activated. Conclusion Oridonin can induce apoptosis and G2/M cell cycle arrest in SGC-7901 cells, which was probably contributed to the down-regulation of protein bcl-2 as well as activation of caspase-3.