抗凋亡基因survivin在食管癌中的表达及其意义

目的　检测抗凋亡基因survivin在食管癌中的表达情况 ,并初步探讨survivin表达与食管癌的关系。方法　 2 7例新鲜的食管癌组织提取RNA ,利用半定量RT PCR方法 ,检测食管癌中survivin的mRNA表达水平 ,与其相配对的正常组织进行比较分析。通过在食管癌细胞系中转染survivin的显性负突变体 (surT34A) ,观察食管癌细胞在软琼脂中的集落形成能力 ,并利用流式细胞仪分析食管癌细胞对抗凋亡能力。结果　 2 7例食管癌组织中 ,有 18例survivin的表达高于配对的正常组织 ,食管癌组织中survivin的表达水平 (2 .0 8± 1.32 )明显高于正常对照组织 (1.2 2± 1.0 9)。在食管癌细胞系中也检测到survivin的表达。转染surT34A的EC970 6细胞在软琼脂中形成的集落数目明显少于对照细胞。survivin过表达可以使得EC970 6细胞在撤血清后凋亡减少 ,而surT34A则使EC970 6细胞凋亡增多。结论　survivin异常高表达与食管癌具有密切相关性。SurT34A可以抑制食管癌细胞的软琼脂集落形成能力 ,并使其对抗凋亡能力减弱 ,部分抑制食管癌细胞的恶性表型。

Expression of survivin and its significance in esophageal cancer

OBJECTIVE: To detect the expression of survivin in esophageal cancer and elucidate its function in esophageal cancer. METHODS: Expression of surviv in was detected in paired normal and tumor tissues from patients with esophageal cancer by semi-quantitative RT-PCR. A dominant-negative survivin (surT34A) was transfected into esophageal cancer EC9706 cells (EC9706surT34A). Colony formation and apoptosis of the parental and surT34A-transfected EC9706 cells were examined in soft agar and by flow cytometry, respectively. RESULTS: Survivin mRNA expression of tumor tissues was higher than normal tissues in 18/27 (66.7%) samples. The expression level of survivin mRNA in tumor tissues (2.08 +/- 1.32) was significantly higher than that in normal tissues (1.22 +/- 1.09). EC9706 surT34A cells formed fewer colonies on agar than the non-transfected ones. After serum withdrawal, EC9706surT34A had higher apoptotic ratio than control, but survivin could reduce the apoptotic ratio. CONCLUSION: Overexpression of survivin is a common eventin esophageal cancer. The dominant-negative survivin can partially inhibit the malignant phenotype of esophageal cancer.