摘要
目的 研究阻断泛素 蛋白酶体通路对胃癌细胞增殖的抑制作用及其机制。方法 将泛素 蛋白酶体通路特异性阻断剂MG 132加入胃癌细胞株SGC 790 1,四甲基偶氮唑蓝 (MTT)法测定细胞抑制效应 ,流式细胞仪 (FCM )检测细胞周期及凋亡 ,DNA片段分析进一步证实凋亡的存在 ,TRAPPCR ELISA法检测端粒酶活性 ,免疫细胞化学检测 p2 7kip1的表达。 结果 MG 132对SGC 790 1细胞有显著抑制作用 ;FCM显示对照组胃癌细胞G0 /G1期比例为 (46 .3± 4 .1) % ,MG 132作用后为 (72 .1± 5 .0 ) % ,较对照组增加 (P <0 .0 1) ,并有明显的亚二倍体凋亡峰 ;细胞DNA抽提电泳后发现特征性凋亡梯状条带 ,TRAPPCR ELISA法检测示MG 132作用胃癌细胞 2 4、4 8、72、96h时A值分别为 0 .197± 0 .0 0 7、0 .0 81± 0 .0 0 5、0 .0 74± 0 .0 0 4、0 .0 6 3± 0 .0 0 2 ,对照组A值分别为 1.80 1± 0 .0 4 8、1.887± 0 .0 72、2 .0 4 7± 0 .0 85、2 .131± 0 .0 76 ;端粒酶活性显著受抑制 (P <0 .0 1) ;p2 7kip1在胃癌细胞中为胞质表达 ,经MG 132作用后 ,胞质、胞核均有表达。结论 MG 132能显著抑制胃癌细胞株SGC 790 1的增殖、诱导其凋亡 ,其机制是增强 p2 7kip1表达 ,使细胞产生G1期阻滞 ,并抑制端粒酶活性。
Objective To investigate the effects of inhibiting ubiquitin proteasome pathway(UPP) on proliferation of gastric carcinoma cells and the possible mechanism was discussed. Methods The gastric carcinoma cell strain SGC 7901 was treated with MG 132 to inhibit its UPP specially. The effect of growth suppression on cells was evaluated with MTT assay. Cell cycle and apoptosis were detected by flow cytometry(FCM). DNA fragment analysis was used for confirming the presence of apoptosis. The activity of telomerase was examined by TRAP PCR ELISA. Expression of p27kip1 was detected by immunocytochemical technique. Results MG 132 had great inhibitory effect on the growth of SGC 7901 cells. The FCM analysis showed that the ratio of G0/G1 phase of control group was (46.3±4.1)%, the ratio of G0/G1 phase of SGC 7901 cells treated with MG 132 increased to (72.1±5.0)% ( P <0.01) and obviously apoptotic sub G1 peak was noticed. Agarose electrophoresis showed marked ladder. TRAP PCR ELISA showed that light absorptions(value A ) of SGC 7901 cells treated with MG 132 after 24 h, 48h, 72 h and 96 h were 0.197 ± 0.007 , 0.081± 0.005, 0.074±0.004 and 0.063±0.002 respectively, light absorptions of control group were 1.801 ±0.048, 1.887±0.072, 2.047±0.085 and 2.131±0.076 respectively. The activity of telomerase was greatly inhibited ( P <0.01). Expression of p27kip1 was positive in plasma of SGC 7901 cells and it was positive in plasma and nuclei of cells treated with MG 132. Conclusions MG 132 can significantly inhibit proliferation of SGC 7901 cells and induce its apoptosis. The mechanisms may possibly relate to enhancing expression of p27kip1, G1 blocking and inhibiting the activity of telomerase.
出处
《中华消化杂志》
CAS
CSCD
北大核心
2004年第2期102-105,共4页
Chinese Journal of Digestion
