穿心莲内酯诱导人食管癌Ec9706细胞凋亡机制研究

Studies on the apoptosis induction mechanism of andrographolide in human esophageal cancer Ec9706 cells

目的在前期工作基础上进一步研究穿心莲内酯(an-drographolide,AD)抑制人食营癌Ec9706细胞增殖和诱导凋亡的机制。方法分光光度法分别检测AD处理Ec9706细胞6、12、18h对caspase-3活性的影响以及AD处理Ec9706细胞6h对caspase-8和caspase-9活性的影响,并用MTT法比较研究在有或无caspase广谱抑制剂Z-VAD-FMK时AD对Ec9706细胞增殖的影响;免疫组化法分析AD处理Ec9706细胞6h对bcl-2基因表达的影响。结果AD(30、60mg.L-1)下调bcl-2基因的表达(P<0.01),提高Ec9706细胞caspase-3和caspase-9活性,对caspase-8活性无明显影响,caspase广谱抑制剂Z-VAD-FMK减弱AD对Ec9706的细胞毒作用。结论AD通过下调bcl-2,激活caspase-9、caspase-3诱导Ec9706细胞凋亡。

Aim To study the mechanism of andrographolide （AD） on the proliferation and apoptosis induction in human esophageal cancer Ec9706 cells. Methods The spectrometry was used to detect the activity of easpase-3 in human esophageal cancer Ee9706 cells treated with or without AD for 6 h,12 h and 18 h,and to detect the activity of caspase-8 and caspase-9 in human esophageal cancer Ee9706 cells treated with or without AD for 6 h. The influence of AD on the proliferation of Ec9706 cells after treatment with or without Z-VAD-FMK （a broad-spectrum easpase inhibitor） was determined by MTT method and the result was compared. The changes of gene expression levels of bel- 2 were determined by immunohistochemical method.Results The expression level of bcl-2 gene was obviously lower in the ceils treated with AD （30 mg · L^-1, P 〈 0.01 ;60 mg · L^-1 ,P 〈 0.01）. The activities of caspase-3 and caspase-9 in Ec9706 cells were significantly increased by AD （30 mg· L^-1 ,60 mg · L^-1 ） , but the activity of caspase-8 wasn＇t significantly changed. The cytotoxicity of AD in human esophageal cancer Ec9706 cells was obviously reduced by Z-VAD- FMK. Conclusions AD induces apoptotic Ec9706 cells death through suppressing bcl-2 and then activa- ting caspase-9 and caspase-3.