虫草素诱导人肝癌HepG-2细胞凋亡及对端粒酶活性影响的研究  

Cordycepin induced apoptosis and affected activity of telomerase in HepG-2 cell line

作　　者：丁向萍 马力[2] 魏书堂[3] 冯国燕 

机构地区：[1]甘肃省第二人民医院消化科,甘肃兰州730000 [2]兰州大学第二医院消化科,甘肃兰州730030 [3]河南大学附属一院消化科,河南开封475000 [4]兰西铁路医院传染科,甘肃兰州730050

出　　处：《中华肿瘤防治杂志》2008年第2期109-113,共5页Chinese Journal of Cancer Prevention and Treatment

摘　　要：目的:研究虫草素(Cordycepin)对人肝癌细胞HepG-2诱导凋亡作用及对端粒酶活性的影响。方法:虫草素处理人肝癌HepG-2细胞株后,用四甲基偶氮唑蓝(MTT)法测定细胞生长抑制效应;倒置相差显微镜下观察肝癌细胞形态变化;用透射电镜观察超微结构的变化及荧光显微镜观察细胞凋亡效应;应用流式细胞仪(FCM)检测细胞周期变化及凋亡率;免疫组化方法测定NF-κBp65的表达;用TRAP-PCR-银染法对肝癌细胞端粒酶活性进行检测。结果:不同浓度的虫草素对HepG-2有明显抑制作用,P=0.002,且呈剂量依赖性;形态学观察也发现,大量细胞的染色质边集、凝聚、核碎裂及凋亡小体产生;免疫组化示,NF-κBp65的表达下调,P=0.0001;FCM检测结果显示虫草素作用后,使细胞阻滞于S期,P=0.0001,并出现典型的"亚二倍体"凋亡峰,同时伴随端粒酶活性下调,P=0.0001。结论:虫草素对人肝癌细胞具有明显抑制作用,其诱导细胞凋亡的机制可能与下调NF-κB的表达并抑制端粒酶活性有关;虫草素与5-FU联合对肝癌细胞无明显协同抑制作用。OBJECTIVE：To explore the effect of Cordycepin on the apoptosis and inhibition of activity telomerase of in HepG-2 cells. METHODS： HepG-2 cells cultured in vitro were acted as the target cells. The proliferation of HepG-2 cells were determined with an methyl thiazolyl tetrazolium （MTT） colorimetric assay. The morphology of HepG-2 cells were observed under a light microscope, fluorescence microscope and transmission electron microscope, respectively. Flow cytometry （FCM） was used to detect cell cycle distribution and apoptotic rates. The expression of NF-κBp65 was examined by the immunohistochemistry method. TRAP silver staining telomerase detection was used to show the activity of telomerase. RESULTS： MTT showed that Cordycepin inhibited proliferation of HepG-2 cells, P = 0. 002. After exposure to Cordycepin, the typical morphological features of apoptosis were observed, including cell shrinkage, plasma membrane blebbing and nuclear condensation. The cell cycle analysis indicated the increased Sub-G1 proportion and apoptotic rate, as well as apparent S phase arrest, P=0. 000 1, and that the expression of NF-κBp65 decreased significantly, P = 0. 000 1, and the activity of telomerase reduced, P= 0. 000 1. CONCLUSION： Cordycepin inhibits the proliferation of HepG-2 cells and induces apoptosis, which may be associated with the downregulation of the expression of NF-κBp65 and decreased activity of telomerase.

关 键 词：虫草素 肝癌细胞HEPG-2 细胞凋亡 端粒酶 NF-ΚBP65 

分 类 号：R735.7[医药卫生—肿瘤]