The Death Mechanism of LoVo Cells Transfected with Cytosine Deaminase Suicide Gene / 中国医师杂志

ABSTRACT

Objective To study the death mechanism of LoVo cells transfected with retroviral vector carrying cytosine deaminase (CD) suicide gene(G1CEACDNa). Methods Plasmid G1CEACDNa was transferred into the LoVo cells using liposomes method. RT-PCR was performed to detect CD mRNA expression using the total RNA extracted with TRIzol reagent. After exposed to 5-FC (1mmol?L -1 ), the cell growth inhibition rate and the “bystander effect” were determined by MTT, the cell ultramicroscopic structure was observed by electron microscope, and cell apoptosis was detected by flow cytometry. Results RT-PCR detection showed that there was 1.5kb band of CD product. The growth of the trasfected LoVo cells started to be inhibited after exposed 5-FC for 48h, and the inhibition rates at 72h,96h and 120h were 30%,50% and 80%, respetively.Electron microscope examination showed that there were apoptotic body. Meanwhile,a few cells showed necrosis alteration.Flow cytometry analysis showed that a few cells appeared apoptosis after exposed to 5-FC for 48h, the apoptotic rate and the necrosis rate at 72h and 96h were 23.8%, 35.1% and 20.4%, 26.0%, respectively. Conclusion The death mechanism of LoVo cells transfected with plasmid G1CEACDNa followed 5-FC treatment was involved in both necrosis and apoptosis. Apoptosis possibly was a mechanism of the bystander effect.