蟾蜍灵联合阿霉素对人肺癌A549细胞体外增殖和凋亡的影响

目的：探讨天然药物蟾蜍灵、阿霉素以及两者联用对非小细胞肺癌A549细胞增殖、凋亡和细胞周期的影 响。方法：采用四甲基偶氮唑盐(methyl thiazolyl tetrazolium，MTT )法观察蟾蜍灵、阿霉素以及两者联用对A549细胞增 殖的影响；采用赫斯特(Hoechst 33342)染色法观察细胞核形态变化；采用流式细胞仪检测蟾蜍灵、阿霉素以及两者联 用对A549细胞凋亡和细胞周期的影响；采用Western印迹检测凋亡蛋白的表达。结果：蟾蜍灵和阿霉素单独用药均能 抑制A549细胞的增殖，且呈剂量与时间依赖关系；与蟾蜍灵和阿霉素单独用药相比，1，20，100 nmol/L蟾蜍灵分别 与1.0 μg/mL阿霉素联合作用A549细胞24，48，72 h的抑制率显著升高(均P<0.05)。蟾蜍灵和阿霉素均可在一定程度上 诱导细胞凋亡，两药联用后诱导细胞凋亡作用显著增强。蟾蜍灵和阿霉素联用可将细胞周期阻滞在S期，并上调凋亡 蛋白caspase-3的表达。结论：蟾蜍灵联合阿霉素可显著抑制A549细胞的增殖，其抗肿瘤的机制可能与诱导细胞凋亡、 细胞周期S期阻滞及凋亡蛋白caspase-3的上调有关。

Effects of bufalin combined with doxorubicin on the proliferation and apoptosis of human lung cancer cell line A549 in vitro

Objective: To explore the effects of bufalin (BUF) combined with doxorubicin (DOX) on the proliferation and apoptosis in human lung cancer cell line A549 in vitro. Methods: Methyl thiazolyl tetrazolium (MTT ) assay was used to measure the inhibitory eff ects of BUF, DOX and their combination on the growth of A549 cells. Hoechst 33342 staining was used to observe the changes of nucleus. Flow cytometry was used to investigate the apoptosis and cell cycle distribution of A549 cells. Western blot was used to examine the expression of apoptotic protein. Results: BUF and DOX showed inhibitory effect on the A549 cells in a dose and time-dependent manner. Compared with BUF or DOX alone, combination of BUF (1, 20, 100 nmol/L) with DOX (1.0 μg/mL) could significantly increase the growth inhibition rate of A549 cells at 24, 36, 72 h, respectively (all P<0.05). BUF and DOX alone could induce apoptosis, and their combination could significantly increase the apoptosis ratio. In addition, BUF combined with DOX could block the cell stage of A549 cells, keep the cell stage stay in S stage and up-regulate the expression of caspase-3. Conclusion: BUF combined with DOX can significantly inhibit the proliferation of A549 cells, which might be related to the induction of apoptosis, cell cycle S phase arrest and caspase-3 upregulation.