小鼠金属硫蛋白-I的表达对HeLa细胞耐药性的影响

Effects of the expression of mouse metallothionein gene in human HeLa cell line on drug resistance

Hp SV2 - neo质粒作为载体 ,在 Eco RI酶切位点上插入小鼠金属硫蛋白 (MT- I)基因 ,然后用 DNA-磷酸钙介导的基因转移法将重组质粒转染 He L a细胞 ,经筛选得到表达 MT- I的抗性细胞克隆。经检测 ,G418抗性细胞内有 MT的特异性表达 ,表达量是未转染细胞的 2 .6倍。用不同浓度顺铂、阿霉素处理细胞 ,观察 MT- I基因的表达与 He L a细胞耐药性的关系。结果表明 :0 .1μmol/ ml顺铂作用细胞 72 h后 ,顺铂对转染和未转染 MT细胞的生长抑制率分别为 34%和 82 % (P<0 .0 5 ) ;半数细胞生长抑制浓度 (IC5 0 )分别为0 .144和 0 .0 6 1μmol/ ml,二者相差 2 .36倍。用 0 .2μmol/ ml阿霉素作用细胞 72 h后 ,对转染和未转染细胞的生长抑制率分别为 18%和 2 5 % ,差异无显著性 (P>0 .0 5 )。结果表明 。

Metallothionein I(MT I) gene was inserted into EcoRIsite by using pSV2 neo plasmid vector. Recombiant plasmid was transfected into HeLa cells by DNA calcium phosphate precipitation technique. MT I expression colones were growing in medium including G418. The amount of MT I expression in transfected cells was found 2 6 times higher than that of non transfected ones. In order to observe the relationship between the expression of MT I gene in cells and drug resistance, cells were treated with different concentrations of cisplatin and adriamycin respectively. The results indicated that cisplatin(0 1μmol/ml) inhibited the growth of both transfected and non transfected cells. The inhibitory rates were 34% and 82% respectively( P <0 05). IC 50 (50% inhibitory concentration for cell growing) was 0 144μmol/ml and 0 061 μmol/ml and the ratio of them was 2 36: 1 after the treatment of cisplatin 72h later. The cells were treated with adriamycin 72h later, the inhibitory rates of transfected and non transfected cells were 18% and 25% separately. The rates showed no significant difference ( P>0 05 ). The results indicated that MT was related to drug resistance of tumor cells. WTHZ