Effects Of Methylation Inhibitors Combined With Simvastatin On Proliferation And Apoptosis Of Human Myeloma Cell Line RPMI8226

OBJECTIVE The experiment focuses on DNA methylation inhibitor 5-Aza-Cd R and Simvastatin(the reductase inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A)monotherapy or combination effect on multiple myeloma cell line RPMI8226 cells.METHODS We use DNA methylation inhibitor 5-Aza-CdR alone or in combination with3-hydroxy-3-methylglutaryl coenzyme A(HMG-COA)reductase inhibitor Simvastatin to process human multiple myeloma cell line RPMI8226 cells in logarithmic growth phase.The inhibition rate of cell proliferation was detected by CCK-8 method,Annexin-V/PI double staining flow cytometry to detect cell apoptosis,Western blotting(Western blot)to detect the expression of apoptosis related protein caspase-3 and protein c-myc proliferation.Experimental groups: DNA methylation inhibitor 5-Aza-Cd R group:0.5 mol/L,2 mol/L,5 mol/L;Simvastatin group: 1 mol/L,2.5 mol/L,5 mol/L;DNA methylation inhibitor 5-Aza-Cd R combined with Simvastatin group: 0.5 mol/L;5-Aza-Cd R combined 1 mol/L,2.5 mol/L,5 mol/L Simvastatin;Control group: no addition of any drugs.Statistical analysis results using SPSS18.0 statistical software;each group of experimental data is represented in ` x ± s,t test was used to compare the differences between the experimental group and control group,single factor analysis of variance statistical differences between groups in experiment group.P <0.05 showed the difference was statistically significant,P <0.01 showed there was a significant difference.RESULTS(1)The results of CCK-8 test showed that DNA methylation inhibitor5-Aza-Cd R or Simvastatin significantly inhibited cell proliferation of RPMI8226 cell line in a dose-depended manner(P<0.01),and these two drugs had a synergistic effect on cell proliferation inhibition;(2)The results of cell apoptosis by Annexin-V/PI double-staining method showed that DNA methylation inhibitor 5-Aza-Cd R or Simvastatin significantly induced the cell apoptosis of multiple myeloma cell line RPMI8226 cell line in a dose-depended manner(P<0.05),and these two drugs had a synergistic effect on inducing cell apoptosis;(3)DNA methylation inhibitor 5-Aza-Cd R or Simvastatin obviously up-regulated caspase-3 expression and down-regulated c-myc expression in a dose-depended manner detected by Western blot(P<0.05),and the synergistic role of these two drugs was more remarkable.CONCLUSIONS DNA methylation inhibitor5-Aza-Cd R or Simvastatin had a significant effect of cell proliferation inhibition and cell apoptosis induction in human multiple myeloma cell line multiple myeloma cell line RPMI8226 in a dose-depended manner,the role of DNA methylation inhibitor 5-Aza-Cd R in combination with Simvastatin was more significant.These results were consistent with caspase-3 expression up-regulation and c-myc expression down-regulation induced by DNA methylation inhibitor 5-Aza-Cd R and Simvastatin alone or in combination in dose-depended manner.These findings indicated that DNA methylation inhibitor 5-Aza-Cd R and Simvastatin may have synergistic effect against multipe myeloma.