bcl-2核酶与Bax在诱导食管癌细胞凋亡中的协同作用

Synergy of Ribozyme Targeted to bcl-2 and Bax Protein in Inducing Apoptosis in Esophageal Carcinoma Cells

为了同时调节二种凋亡相关蛋白的表达诱导肿瘤细胞凋亡 ,探索肿瘤基因治疗的可能性 ,同时转入可诱导表达的特异性切割 bcl- 2的核酶基因及 bax基因 ,间接免疫荧光标记法检测 Bcl- 2及Bax蛋白的表达量 ,用 TUNEL、流式细胞术及琼脂糖凝胶电泳检测细胞凋亡 .共转染后 Bcl- 2蛋白表达下降 ,同时 Bax蛋白表达升高 ,导致 30 %左右细胞凋亡 ,并可使细胞对紫杉醇的敏感度增加近4倍 ,使紫杉醇有效作用时间缩短近一倍 .同时调节二个凋亡相关基因可导致细胞凋亡 ,并能有效促进化疗药物诱导的凋亡 .同时校正多个基因的异常表达 ,比仅仅改变单个基因可更有效地达到治疗肿瘤的目的 .

Apoptosis in tumor cells was induced by regulating the expression of two apoptosis\|associated proteins at the same time to investigate the possibility of curing tumor by gene therapy.The bax gene and hammerhead ribozyme specially targeted to bcl\|2 mRNA whose expression can be induced by ZnSO 4 were transfected into human esophageal carcinoma cell line Eca109 simultaneously and selected by G418.Transfectant was induced by 120 μmol/L ZnSO 4 for two days.The expression of the Bcl\|2 and Bax protein was identified by indirect immunofluorescent.Apoptosis was determined by TUNEL assay,apoptosis peak analysis and agarose gel electrophoresis.Results showed that the expression of Bcl\|2 was decreased whereas the expression of Bax was increased after being co\|transfected.30% or so apoptotic cells were induced.Moreover,the sensitivity to paclitaxel was enhanced 4 times and the effective time of paclitaxel was shortened nearly by half.These data demonstrate that regulating the expression of two apoptosis\|associated genes at the same time can induce apoptosis in tumor cells and accelerate apoptosis induced by chemotherapeutic drugs.It is more effective to cure tumor by correcting abnormal expression of multiple genes than by adjusting expression of single gene.