HSP70 Antisense Oligodeoxynucleotides Induce Senescence Of Cell Line MRC-5

[ Objectives ] The study was designed to investigate the HSP70 expression, cell apoptosis and the percentage of the G1 phase of cell line MRC-5 at different times, using a specific anti-sense oligodeoxynucleotides which is matched with human HSP70mRNA, and to research whether the reduced expression of HSP70 will induce the cell senescence.[Methods] 1)21 groups were designed according to the different ODN and liposome concentration and MTT method was used to investigate the cell proliferation of different groups. 2)Flow cytometry, fluorescence microscope were applied to measure fluorescence intensity, apoptosis and cell cycle distribution in 12 hours, lday,3days,and 5 days respectively after transfection. 3)Three groups, which were control, sense and anti-sense oligodeoxynucleotides group, were set up. SA- β -Gal staining was used to detect the senescence cells at different time points.[Results] l)At each time point, average fluorescence intensity of the anti-sense ODN group were significantly lower than that of the sense group(P<0.05).While the strongest inhibit effect of HSP70 anti-sense oligodeoxynucleotides was at 12 hours after transfection. Both sense and anti-sense ODN showed the peak of the protein expression, but the peak of the anti-sense group(l day after transfection) was in advance to the sense group(3 days after transfection). 2)The percentage of the apoptosis cells inthe anti-sense group was significantly higher than that of the sense group at each time point(P<0.05),both groups reached the peak in 1 day after transfection, then gradually descended. 3) Cells arrested in the Gl phase were increasing with time, the anti-sense group has significantly higher percentage than the sense group(P<0.05). 4)SA- P -Gal staining showed that the number of positive cells in the anti-sense group was more than those in sense or control group, and that the positive cells were increasing with time in every group.[Conclusions] HSP70 anti-sense oligodeoxynucleotides can block the HSP70 protein expression, interrupt the cell cycle and induce the cell senescence.