细胞色素氧化酶P450 3A4基因联合环磷酰胺的体外抗肿瘤效应

目的 克隆细胞色素氧化酶P450 3A4（CYP3A4）基因，构建真核表达质粒并导入K562细胞进行表达，研究CYP3A4联合环磷酰胺（CPA）的体外抗肿瘤效应。方法 利用RT-PCR从人肝细胞中克隆CYP3A4基因，构建重组真核表达载体。脂质体法导入K562细胞，RT-PCR和Western blot检测CYP3A4基因在K562细胞中的表达并筛选稳定转染的细胞克隆。MTT法检测CYP3A4联合CPA对肿瘤细胞的抑制作用。结果 成功克隆CYP3A4基因并构建了真核表达质粒pcDNA3.1/myc-His A(+)-CYP3A4。RT-PCR和Western blot分别显示转基因组的CYP3A4 mRNA和蛋白质表达水平均显著高于转空载体组和对照组。MTT示转基因组IC₅₀值为1.090 16 mmol/L，明显低于转空载体组和对照组。酶诱导剂和抑制剂分别能够减低和增高转基因组IC₅₀。结论 CYP3A4体外具有联合CPA的抗肿瘤作用，这种作用能够被CYP3A4相应的诱导剂和抑制剂增强或减低。

The anti-tumor effect of Cytochrome oxidase P450 3A4 combined with Cyclophosphamide in vitro

Objective To clone CYP3A4 gene and to construct CYP3A4 recombinant mammalian expression vectors which are transferred into K562 cells for expression,and detect the anti-tumor effect of CYP3A4 combined with Cyclophosphamide (CPA) in vitro.Methods Mammalian expression vector containing CYP3A4 gene cloned from human hepatocytes by RT-PCR were constructed and transferred into K562 cells via liposome. The expression of CYP3A4 was detected by RT-PCR and Western blot respectively. MTT detected the anti-tumor effect of CYP3A4 recombinant mammalian expression vectors combined with CPA.Results We cloned CYP3A4 gene and constructed the recombinant mammalian expression vectors pcDNA3, 1/myc-His A (+)-CYP3A4 successfully. Both RT-PCR and Western blot showed significantly higher mRNA and protein expression of CYP3A4 in gene-transfected group than in empty vector-transfected controls and in empty cells controls. The IC_(50) values were 1. 090 16 mmol/L in gene-transfected group, which were significantly lower than in other two groups and could be reduced and increased by the revulsant and inhibitor respectively.Conclusions CYP3A4 recombinant mammalian expression vectors had anti-tumor effect cooperating with CPA, and the effect could be increased and reduced by the revulsant and inhibitor of CYP3A4 respectively.