硫链丝菌肽抑制FoxM1表达后对鼻咽癌细胞凋亡的影响及机制探讨

Effect of thiostrepton on the apoptosis of nasopharyngeal carcinoma CNE-2 cell line

摘要:

目的：探讨硫链丝菌肽（thiostrepton，TST）抑制鼻咽癌（nasopharyngeal carcinoma，NPC）细胞CNE-2中叉头框M1（fork－head box M1，FoxM1）表达后凋亡作用的增强及可能机制。方法：细胞培养传代后过夜培养，将细胞分为3组：对照组未加TST、只加0.1%二甲基亚砜（dimethyl sulfoxide，DMSO）的培养液，4 μmol/L TST组， 8 μmol/L TST组，培养48 h后，进行不同的实验手段观察处理。显微镜下观察TST作用CNE-2后细胞形态学改变；Hoechst33342染色后显微镜下计数凋亡细胞个数，检测TST对CNE-2细胞凋亡的影响；流式细胞术检测TST作用CNE-2细胞后，细胞凋亡率的变化；Western blot检测TST作用CNE-2后细胞中FoxM1及凋亡相关蛋白的表达变化。结果：TST作用CNE-2细胞后细胞形态逐渐向凋亡发展，呈剂量依赖性；Hoechst33342染色检测凋亡结果显示各组凋亡细胞数为：对照组（0.1% DMSO），4 μmol/L TST组和8 μmol/L TST组细胞凋亡数目分别为：0.60±0.55，3.60±0.89，7.00±1.58，TST对CNE-2细胞凋亡的影响呈剂量依赖性增加，对照组与TST组比较差别有统计学意义（F=42.72，P<0.01）；流式细胞术检测凋亡结果显示：对照组（0.1% DMSO）（1.87±0.74）%；4 μmol/L TST组（10.55±0.75）%；8 μmol/L TST组（19.35±2.49）%，随着TST浓度增加，CNE-2细胞凋亡率增加，对照组与TST组比较差别有统计学意义（F=94.50，P<0.01）；Western blot检测发现TST作用CNE-2后细胞中FoxM1蛋白表达下降，凋亡相关蛋白表达发生变化。结论：硫链丝菌肽在体外可以有效降低NPC CNE-2细胞中FoxM1表达，并抑制NPC CNE-2细胞生长，诱导其凋亡。

Abstract:

Objective：To investigate the effect of thiostrepton（TST） on the apoptosis of nasopharyngeal carcinoma CNE-2 cell line. Methods：CNE-2 cells were delivered into a control group and a group treated with 4 μmol/L or 8 μmol/L of TST for 48 h. Then CNE-2 cell morphology was observed by inverted phase contrast microscope. The apoptosis rate was analyzed by Hoechst33342 and flow cytometry. Expressions of FoxM1 protein and apoptosis protein were detected by Western blot. Results：CNE-2 cells underwent dra－matic changes in morphology after being treated with different concentrations of TST. Hoechst33342 assay showed that exposure to TST resulted in dose-dependent increase of CNE-2 cell apoptosis. Apoptosis cell numbers of control group，4 μmol/L TST group，8 μmol/L TST group were 0.60±0.55，3.60±0.89，7.00±1.58. Flow cytometry assay indicated that the apoptosis rate was increased with the increase of TST concentration；apotosis pencentages of control group，4 μmol/L TST group，8 μmol/L TST group were （1.87±0.74）%，（10.55±0.75）%，（19.35±2.49）%. Western blot showed that the expression levels of FoxM1 protein and apoptosis associated proteins decreased with the increase of TST concentration. Conclusion：TST can effectively inhibit CNE-2 cell proliferation and induce apoptosis in nasopharyngeal carcinoma.