【摘要】 目的:观察西妥昔单抗联合低温热疗诱导人鼻咽癌细胞株CNE凋亡的效果,并初步探讨其可能的机制。方法:试验分对照组、单靶组、单热组及热靶组,MTT法测定西妥昔单抗对CNE细胞株48h20～30%抑制的药物浓度;以该浓度药物与低温热疗(43℃,30分钟)联合,Hoechst33258荧光染色法观察细胞凋亡形态学变化;流式细胞术检测24h、48h凋亡率;western blot检测Bax、Bcl-2、EGFR蛋白的表达。结果:以48h20～30%抑制率的药物浓度(IC20～30)为试验的工作浓度,确定西妥昔单抗对CNE细胞株的工作浓度为10ug/ml;荧光染色法观察到热靶组CNE细胞发生典型的凋亡形态学改变;流式凋亡检测显示24、48h热靶组凋亡率显著高于相应单靶组、单热组及对照组(P<0.05)。western blot检测显示各处理组较之对照组都有上调Bax、下调Bcl-2、EGFR蛋白表达的作用,以热靶组最为显著(P<0.05);热疗后EGFR蛋白表达逐渐下调。结论:西妥昔单抗联合低温热疗能显著增加CNE细胞的凋亡率,这可能与EGFR的下调与受抑,进而上调Bax、下调Bcl-2蛋白的表达促进凋亡有关。更多还原

【Abstract】 Objective:To investigate the apoptosis and its mechanism induced by cetuximab combined with hypothermia in CNE cells.Methods:The working concentration of cetuximab was defined as its inhibiting concentration(IC)(20～30%) at 48 hours action a-gainst CNE which was determined by MTT assay.Apoptosis was assayed by fluorescent Hocehst 33258 staining and flow cytometry(FCM) in four experimental groups:control group without treatment,cetuximab(T) or hyperthermia(H)(43℃,30min)alone,cetuximab combined with hypothermia(TH).The expression of Bcl-2,Bax,EGFR proteins were determined by Western Blot.Results:A working concentration of Cetuximab at 10 μg/ml was obtained and subsequently used in all experiments.Characteristical changes of apoptosis in cells were observed in all the experient groups,especially in TH group;FCM also showed more prominent apoptosis induced by TH group than the control,T and H group.Western Blot analysis indicated that the expression of the proteins Bax has significantly increased while Bcl-2 decreased by the treatment.EGFR decreased gradually after treatment by hypothermia.Conclusion:Cetuximab combined with hypothermia synergistically increases the apoptosis in CNE cells,possibly through the Bax up-regulation and Bcl-2 down-regulation by EGFR down-regulation.更多还原