Killing effects of PNP-CD chimeric suicide gene vector on HCC cells / 中华肝胆外科杂志

ABSTRACT

Objective To investigate the cytotoxic effects and mechanism of PNP-CD chimeric gene vector originated from PNP/MeP-dR system on HCC cells. Methods The fusion suicide gene PNP-CD obtained by site directed mutagenesis technique was subcloned into pcDNA3.0 to construct a eukaryotic expression vector containing a chimeric gene, pcDNA3.0/ PNP-CD. After being identified by recombinant enzyme, PCR and subsequent sequencing, it was transfected into HepG2 cells by liposome-mediation method. The G418-resistant cellular clone with stable transfection of pcDNA3.0/PNP-CD, HepG2/PNP-CD was established by selection. The expression of PNP-CD gene was also verified by RT-PCR and Western blotting. The curve of cellular growth was assayed by Trypan blue exclusion. The cellular sensitivity of HepG2/PNP-CD to its specific prodrugs and its bystander effects were also assayed by MTT method. Results The chimeric gene, PNP-CD, was inserted into pcDNA3.0 correctly, and the stable expression of pcDNA3.0/PNP-CD in HepG2 cells was confirmed.This cellular clone was highly sensitive to its corresponding prodrugs. It was indicated that its bystander effects with the synergetic treatment of its specific prodrugs were substantially higher than those caused by the same vector with the administration of only a single prodrug, MeP-dR. Conclusion The bi-functional fusion suicide gene vector, pcDNA3.0/PNP-CD, yields powerful cytotoxic effects on HCC cells in the presence of the synergetic treatment of its specific prodrugs, which would be a high-performance therapeutic vector in gene therapy for liver cancer.