中文摘要：

目的研究雷公藤红素对肝癌细胞SMMC-7721的增殖和凋亡的影响及机制。方法应用CCK8试剂检测雷公藤红素对SMMC-7721细胞的毒性和增殖影响,用软琼脂克隆形成试验检测药物对肝癌细胞的克隆形成能力的干预,通过核染色及检测活化caspase-3水平观察细胞凋亡情况,用流式细胞术检测药物干预对细胞周期分布的影响,并用Western blot检测细胞周期相关蛋白细胞周期素B1（cyclin B1）及细胞分裂周期蛋白2（cell division cycle protein 2,cdc2）水平。结果雷公藤红素以剂量依赖性方式使SMMC-7721细胞的增殖下降和克隆形成减少,使细胞凋亡增加及细胞周期阻滞在G2/M期,同时增加失活cdc2表达,并导致cyclin B1的积聚。结论雷公藤红素可显著抑制肝癌细胞SMMC-7721的增殖并促进细胞凋亡,对分裂周期相关蛋白调控导致的分裂阻滞可能是影响其对细胞凋亡和增殖作用的机制之一。

英文摘要：

AIM To study the effect and potential mechanism of celastrol on apoptosis and cell cycle of hepa- tocarcinoma cell line SMMC-7721. METHODS Cytotoxicity and the effect of celastrol on cell proliferation were assessed by CCK8 assay. Colony formation assay was used to determine the intervention of the compound for the a- bility of cell growth and tumorigenesis. The appearance of cellular nuclei was observed through DAPI stain. Cell cycle was determined using a flow cytometer after PI stain. And Western blot was used to detect protein level of cleaved caspase-3, cyclin B1 and phospho-cdc2. RESULTS Compared with control, celastrol decreased cell proliferation, retarded colony formation in a dose dependent manner. The compound increased cell apoptosis and cell cycle arrest at the G2/M phase. Simultaneously, it increased the level of inactive cdc2 and the expression of cyclin B1. CONCLUSION Celastrol could inhibit SMMC-7721 cell proliferation and promote cell apoptosis. The mitotic cycle arrest by this compound through regulation of cell cycle related proteins might partially contribute to the underlying mechanism.