核酶对人肺腺癌细胞多药耐药的逆转

Reversion of multidrug resistance in vitro of lung adenocarcinoma by mdr1 ribozyme

目的 探讨针对多药耐药基因 (mdr1)的核酶对肺腺癌细胞多药耐药的逆转作用。方法以mdr1mRNA 880位点为靶位点 ,通过脂质体介导 ,将抗mdr1核酶表达质粒 (pHβApr 1neo/mdr1 Rb)导入肺腺癌耐药细胞株A5 49/R。分别采用RT PCR、流式细胞仪检测术、罗丹明聚集及MTT方法 ,观察细胞的mdr1mRNA、P糖蛋白 (P glycoprotein ,Pgp)表达和对阿霉素敏感性的变化。结果 经抗mdr1核酶处理的细胞 ,mdr1mRNA、Pgp明显降低 ,细胞内罗丹明聚集 ,对阿霉素的敏感性提高 2 0 0倍。结论 针对多药耐药基因mdr1的核酶可明显降解mdr1mRNA ,抑制Pgp的表达 。

Objective To investigate the possibility of reversion of multidrug resistant (MDR) in lung adenocarcinoma resistant cell line A549/R by mdr1 ribozyme.Methods With GUC at 880 site of mdr1 mRNA selected as target point, plasmid expressing mdr1 ribozyme (pH β Apr 1 neo/mdr1 Rb) was transduced to A549/R by lipofectin. The expression of mdr1 mRNA and Pgp, cellular rhodamine accumulation and sensitivity to doxorubicin were examined in ribozyme transduced and non transduced cells.Results Transduction of mdr1 ribozyme to A549/R cells led to decrease in mdr1 mRNA and Pgp expression; increase in rhodamine accumulation. The sensitivity of the ribozyme transduced cells to doxorubicin was 200 fold as high as that of the parental drug resistant cells.Conclusion MDR of lung adenocarcinoma resistant cell line A549/R can be effectively reversed with mdr1 ribozyme by cleavage of mdr1 mRNA and inhibition of Pgp expression.