突变型与野生型TNF-α诱导肿瘤细胞的凋亡  

Apoptosis of tumor cells induced by mutant and wild type TNF-α

作　　者：李瑶琛[1] 程碧珍[1] 李康生[1] 

机构地区：[1]汕头大学医学院微生物学与免疫学研究室,广东汕头515041

出　　处：《第四军医大学学报》2005年第24期2237-2240,共4页Journal of the Fourth Military Medical University

摘　　要：目的比较重组人突变型471rhTNF-α(mt471rhTNF-α)与野生型rhTNF-α(wt rhTNF-α)诱导肿瘤细胞发生凋亡的能力,并对mt471rhTNF-α诱导肿瘤细胞发生凋亡的作用机制进行初步研究.方法以乳腺癌细胞系ZR75-1细胞为靶细胞,应用基因组DNA琼脂糖凝胶电泳及流式细胞技术分析mt471rhTNF-α与wt rhTNF-α诱导肿瘤细胞凋亡的情况;利用以ELISA为基础的Trans AMTM NF-κB p65试剂盒检测经mt471rhTNF-α或wt rhTNF-α处理的ZR75-1细胞核因子NF-κB的活化情况,以便对其诱导凋亡的机制进行初步的研究.结果20g/L琼脂糖凝胶电泳显示,mt471rhTNF-α处理组的ZR75-1细胞基因组DNA呈现明显的ladder状分布,wtrhTNF-α处理组的“ladder”条带明显减弱;流式细胞仪分析显示,mt471rhTNF-α诱导的细胞凋亡峰面积高于wt rhTNF-α处理组.NF-κB活化检测结果显示,当两型rhTNF-α浓度增高到50μg/L时,wt rhTNF-α处理组的NF-κB的活化量明显高于同浓度的mt471rhTNF-α处理组(P=0.002).结论mt471rhTNF-α诱导肿瘤细胞凋亡的能力明显优于wt rhTNF-α;肿瘤细胞内NF-κB活化明显受抑是mt471rhTNF-α诱导凋亡能力增强的主要原因之一.AIM： To compare the apoptosis-induced ability of recombinant human mutant type 471 rhTNF-α（ mt 471- rhTNF-α） with that of wild type rhTNF-α （wt rhTNF-α and to study the apoptotic mechanism induced by mt 471rhTNF- α. METHODS. The apoptosis of ZR75-1 cells, a breast cancer cell line, induced by mt 471rhTNF-α or wt rhTNF-α was analyzed and compared by 20 g/L agarose gel electrophoresis and flow cytometry techniques. The activation profiles of nuclear factor NF-kB in ZR75-1 cells untreated and treated by mt 471rhTNF-α or wt rhTNF-α were detected using Trans AMTM NF-kB p65 kit based on ELISA for further study of the apoptotic mechanism induced by mt 471rhTNF- α. RESULTS： The results from 20 g/L agarose gel electrophoresis of genomic DNA indicated that ZR75-1 cells treated by mt 471rhTNF-α provided a typical apoptotic ladder pattern of DNA fragmentation, whereas weakened ladders were observed in ZR75-1 cells treated by wt rhTNF-α. Flow cytometry showed that the cell apoptotic rate in mt 471- rhTNF-α treated group was 43%, but 25% in wt rhTNF-α treated group, The mt 471rhTNF-α held a strong apoptosisinducible ability. The results of DNA-binding activity of NF- kB showed that NF-kB activation induced by wt rhTNF-α was significantly higher than that of mt 471rhTNF-α when the protein concentration of mt 471rhTNF-α or wt rhTNF-α reached 50 μg/L （ P =0.00：2）. CONCLUSION： The apoptosis-induced ability of mt 471rhTNF-α is superior to that of wt rhTNF-α. One of the possible reasons for the enhanced apoptosis-induced ability may be that NF-kB activation is inhibited in tumor cells treated with mt 471rhTNF-α.

关 键 词：肿瘤 突变型471 RHTNF-Α 野生型rhTNF—α NF—kB 细胞凋亡 

分 类 号：R73-3[医药卫生—肿瘤]