地塞米松联合顺铂对肺腺癌 A549 细胞增殖和凋亡的影响

目的：探讨地塞米松（dexamethasone，DEX）联合顺铂（cisplatin，DDP）在体外对肺腺癌2,549细胞增殖和凋亡的影响及可能的机制。方法：体外培养人肺腺癌A549细胞。MTF法检测DDP和DEX对A549细胞增殖的影响。流式细胞术分析细胞周期及细胞凋亡。Westernblot检测DEX和DDP对A549细胞内VDR表达水平的影响。结果：地塞米松≥500nmol／L浓度时对A549细胞有一定的增殖抑制作用（P〈0．05）；〈500nmol／L浓度时对A549细胞无明显抑制作用（P〉0．05）；DDP浓度在0．3125-10ug／ml范围内对A549细胞增殖有明显的抑制作用，并呈浓度及时间依赖性（P〈0．05）。流式细胞仪检测到DDP＋DEX组的G．期细胞比例下降，s期比例上升（P〈0．05），且细胞凋亡数目增加（P〈0．05）。Westernblot观察到DDP＋DEX组VDR表达水平明显升高（P〈0．05）。结论：DEX可能通过上调A549细胞内VDR表达水平，与顺铂协同促进细胞凋亡、诱导细胞周期阻滞，进而提高顺铂化疗敏感性。

Effects of dexamethasone combined with cisplatin on proliferation and apoptosis of hu- man pulmonary adenocarcinoma cell A549

Objective：To investigate the effects of proliferation and apoptosis and the mechanism induced by dexa- methasone （DEX） and cisplatin （DDP） in human pulmonary adenocarcinoma cell A549 and possible mechanism. Methods：Subculture human pulmonary adenocarcinoma cell A549 in vitro, and was treated with DEX and DDP. The proliferation ability of the A549 cells were detected by MTI7 method. The cell cycle and cell apoptosis were analyzed by flow cytometry. The expression level of vitamin D receptor was evaluated by Western blot. Results：The concentra- tion of DEX above 500nmol/L could inhibit the proliferation of A549 cells obviously, the inhibitory rate depends on the concentration and time （P 〈 0.05 ）. The concentration of DEX less than 500nmol/L couldn＇t inhibit the prolifera- tion of A549 cells （P 〉 O. 05 ）. The concentration of DDP in 0.3125 - lOp, g/ml could inhibit the proliferation of A549 cells obviously, the inhibitory rate depends on the concentration and time （ P 〈 0.05 ）. The cell cycle and cell apopto- sis analyzed by flow cytometry, the DDP ＋ DEX group G1 phase and S phase cell percentage drops to rise more obvious （P 〈 0.05）. Western blot observed the VDR expression level of DDP ＋ DEX group increased significantly （ P 〈 0.05）. Conclusion ： DEX combined with DDP could increace the expression of VDR on the proliferation of A549 cells, and promot the apoptosis and induce cell cycle arrest, and improve the cisplatin chemotherapy sensitivity.