Silencing TIGAR Gene Increase Apoptosis Of HepG2 Cells Induced By Epirubicin

Objective: To study whether the inhibition of TIGAR gene expression could strengthen the apoptosis effect induced by Epirubicin.Method: To chemosynthesize a fluorescently-labeled TIGAR-small interfering RNA targeting TIGAR mRNA.The interfering efficacy was tested by Western blot analysis.MTT assay was used to determine the 50% inhibiting concentration(IC50) that Epirubicin acts on HepG2 cells.Using western blot method to examine the expression of TIGAR protein in HepG2 cells treated with Epirubicin and/or RNAi.DAPI was used to stain the cells to observe apoptosis .For cell apoptosis assay ,flow cytometry was used.Results: Analysis by Western blot showed the basic expression of TIGAR protein is high. The TIGAR-siRNA interfering effect is fine.Analysis of MTT assay showed,the IC50, Epirubicin acting on HepG2 cells,is 1.916μg/ml.The result of Western blot showed in one group treated with Epirubicin,the expression of TIGAR protein upgraded with increase of Epirubicin concentration.;by contrast,in the other group treated with Epirubicin and RNAi,the expression decreased dramatically,and bare no relation with the time course of Epirubicin concentration.With analysis of FCM and Hoechst staining,it was shown that TIGAR RNAi itself was not able to induce significant apoptosis on HepG2 cells,but it could increase the apoptosis induced by EPI.Conclusion:Scilecing the TIGAR gene can increase the apoptosis of HepG2 cells induced by Epirubicin .