17-AAG联合EGCG对人鼻咽癌细胞株增殖和凋亡的影响及机制研究

目的　研究17-烯丙胺-17-去甲氧基格尔德霉素（17-allyamino-17-demethoxygeldanamycin，17-AAG）和表没食子儿茶素没食子酸酯（epigallocatechin-3-gallate，EGCG）单药或联合使用对人鼻咽癌细胞CNE的凋亡诱导作用，寻找鼻咽癌治疗的新方向。方法　MTT法和荧光染色分别检测CNE增殖抑制率及细胞形态的变化；RT-PCR检测Bcl-2、Bax和Caspase-3 mRNA的表达。结果　①17-AAG、EGCG单独作用于CNE细胞24、48、72 h，均有抑制作用，与时间和剂量相关（P＜0.01）；两者联合抑制作用显著增加，且表现出时间、剂量依赖性（P＜0.01）。②RT-PCR检测联合用药时Caspase-3和Bax的mRNA表达明显高于单独用药组，Bcl-2 mRNA明显低于单独用药组。结论　17-AAG联合EGCG可显著抑制CNE细胞增殖，其可能与上调Bax和Caspase-3的表达发挥其抗鼻咽癌细胞的生长增殖作用。

Effect and mechanism of heat shock protein inhibitors on cell proliferation and apoptosis in human nasopharyngeal carcinoma

OBJECTIVE To study the effect of different concentrations of 17-AAG and EGCG monotherapy or in combination on the induced apoptosis in human nasopharyngeal carcinoma, and to explore new molecular targets for the treatment of nasopharyngeal carcinoma. METHODS MTT colorimetric method and fluorescent staining were used to detect the change of CNE proliferation inhibition rate and cell morphology. And furthermore, the expression level of Bcl-2, Bax, Caspase-3 were detected by RT-PCR. RESULTS 1. 17-AAG or EGCG alone had inhibitory effect on the human nasopharyngeal carcinoma CNE cells at 24 h, 48h and 72 h, and it was related with time and dose(P<0.01). The inhibition effect of combination of 17-AAG and EGCG was significantly increased,which was time and dose dependent(P<0.01). 2. RT-PCR was used to detect the mRNA expression level of Bcl-2, Bax and caspase-3. The level of Caspase-3 and Bax mRNA expression after treated by 17-AAG and EGCG was significantly higher, and the level of bcl-2 mRNA expression was lower than that after treated by 17-AAG or EGCG alone. CONCLUSION Our investigation implied that 17-AAG and EGCG in combination can effectively inhibit the proliferation of human nasopharyngeal carcinoma CNE cells. The involved mechanisms may be associated with the upregulation of Bax and Caspase-3 expression.