羟基喜树碱诱导胃癌细胞凋亡的作用机制初步研究  

The mechanisms of apoptosis induced by hydroxycamptothecin in gastric cancer cells

作　　者：涂水平[1] 江石湖[1] 谭继宏[1] 钟捷[1] 乔敏敏[1] 蒋晓华[1] 章永平[1] 袁耀宗[1] 吴云林[1] 吴裕炘[1] 

机构地区：[1]上海第二医科大学瑞金医院消化科,200025

出　　处：《中华消化杂志》2001年第5期274-277,共4页Chinese Journal of Digestion

基　　金：上海市科学和技术发展基金!资助 (9641190 35 )

摘　　要：目的　研究羟基喜树碱 (HCPT)诱导胃癌细胞的凋亡作用及对凋亡相关基因 p5 3、c myc、bcl 2、bcl xl和bcl xs表达的影响 ,探讨其诱导胃癌细胞凋亡的作用机制。方法　应用TUNEL染色、流式细胞仪、免疫组化和RT PCR技术等研究HCPT对胃癌细胞SGC - 790 1和MKN 45的诱导凋亡作用和对凋亡相关基因表达的影响。结果　HCPT作用于细胞后 ,可看到较为典型的细胞凋亡的形态学变化 :细胞核固缩 ,染色质凝集 ,呈新月型紧贴于核膜周边 ,核碎裂 ,染色质片段化 ,凋亡小体形成等。流式细胞仪DNA直方图上出现典型的亚二倍体的“凋亡峰”。流式细胞仪计数显示 ,10 μg/ml的HCPT诱导胃癌细胞SGC 790 1和MKN 45的凋亡率为 2 1.88%和 12 .34%。TUNEL染色法显示 ,细胞凋亡指数在1.86 %～ 9.5 4%之间。免疫组化和RT PCR结果显示 :HCPT能够明显下调SGC 790 1细胞的 p5 3和bcl 2基因的蛋白和mRNA表达 ;对SGC 790 1细胞的c myc、bcl xl和bcl xs基因的蛋白表达无影响。HCPT作用后MKN 45细胞的p5 3蛋白和mRNA的表达增加 ;对MKN 45细胞的bcl 2、c myc、bcl xl和bcl xs基因的表达无影响。结论　HCPT能够诱导胃癌细胞凋亡 ,可能是通过调控胃癌细胞的 p5 3和bcl 2的表达而诱导胃癌细胞凋亡。Objective To study the mechanisms of Hydroxycamptothecin (HCPT) induced apoptosis of gastric cancer cells by detecting the expressions of p53, c myc, bcl 2, bcl xl, bcl xs genes. Methods Apoptosis of gastric cancer cells (SGC 7901,MKN 45) was measured by TUNEL and flow cytometry. The levels of mRNA and protein of p53, c myc, bcl 2, bcl xl,bcl xs genes were determined by reverse transcriptase polymerase chain reaction analysis and immunohistochemistry, respectively. Results Gastric cancer cells SGC 7901, MKN 45 presented some morphologic features of apoptosis, including cell shrinkage, nuclear condensation, DNA fragmentation, formation of apoptotic bodies, after 12 hours expourse to HCPT. Some typical subdiploid peaks before G0/G1 phase were observed. The apoptotic rates of SGC 7901, MKN 45 were 21.88% and 12.34%, respectively. The levels of p53 and bcl 2 mRNA and protein were downregulated after treated with HCPT in SGC 7901 cells. The levels proteins of c myc, bcl xl, bcl xs were unchanged after expourse to HCPT in SGC 7901 cells. The levels of p53 mRNA and protein were increased after treated with HCPT in MKN 45 cells. While the expressions of protein of bcl 2, c myc, bcl xl, bcl xs genes were not affected by HCPT in MKN 45 cells. Conclusion The results have showed HCPT induced apoptosis in gastric cancer cells might be regulated through influencing the expressions of p53 and bcl 2 genes.

关 键 词：胃癌细胞 羟基喜树碱 细胞凋亡 凋亡相关基因 

分 类 号：R735.2[医药卫生—肿瘤] R73－36[医药卫生—临床医学]