The anti-tumor effect of Cytochrome oxidase P450 3A4 combined with Cyclophosphamide in vitro / 复旦学报（医学版）

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.

Tumor targeted gene therapy / 핵의학분자영상

Knowledge of molecular mechanisms governing malignant transformation brings new opportunities for therapeutic intervention against cancer using novel approaches. One of them is gene therapy based on the transfer of genetic material to an organism with the aim of correcting a disease. The application of gene therapy to the cancer treatment has led to the development of new experimental approaches such as suicidal gene therapy, inhibition of oncogenes and restoration of tumor-suppressor genes. Suicidal gene therapy is based on the expression in tumor cells of a gene encoding an enzyme that converts a prodrug into a toxic product. Representative suicidal genes are Herpes simplex virus type 1 thymidine kinase (HSV1-tk) and cytosine deaminase (CD). Especially, physicians and scientists of nuclear medicine field take an interest in suicidal gene therapy because they can monitor the location and magnitude, and duration of expression of HSV1-tk and CD by PET scanner.