A preliminary study on the mechanism of VP_3 inducing apoptosis in the multidrug-resistant model of human osteosarcoma cell line

ObjectiveTo study the mechanism of VP 3 inducing apoptosis in the multidrug-resistant model of human osteosarcoma cell line (R-OS-732).Methods363 bp VP 3 gene was cloned into the vector pIRES1 and the recombinant eukaryon expression vector pIRVP 3 was transfected into R-OS-732 cells with liposome.The expression of VP 3 gene at transcription level was proved by RT-PCR.The transfected R-OS-732 cells were collected after they were cultivated 48 hours.The genomic DNA extracted from the cells were observed by agarose gel electrophoresis.The apoptosis rate of the cells was analysed by flow cytometry.The expression of p53 and bcl-2 was determined by Western-blot.ResultsThe transfected R-OS-732 cells were collected after they were cultivated 48 hours,many typical apoptosis cells in the transfected group were observed under electronmicroscope,DNA ladder of them was observed through agarose gel electrophoresis,and only one band was observed in the control group.Flow cytometry analysis showed that the apoptosis rate of the cells in the transfected group was relatively higher than that in the control group(P0.01).There was no difference in the expression of p53 and bcl-2 of the two groups.ConclusionApoptin can induce apoptosis in the multidurg-resistant model of human osteosarcoma cell line(R-OS-732) without p53 and bcl-2.