Effect of α-tocopherol associated protein in the regulation of the apoptosis induced by oxidative stress in prostate cancer cells

Abstract

Objective To investigate the effect of α-tocopherol associated protein (TAP) gene in the regulation of the apoptosis induced by oxidative stress.Methods The plasmid pEGFP-N3-TAP expressing human TAP gene was transfected into PC-3 cells by the transfection reagent DMRIEC,and the expression of TAP was detected by Western blotting.Reverse transcription-polymerase chain reaction ( RT-PCR) and Western blotting were used to detect the change of TAP gene expression in the oxidative stress cell model established by using hydrogen peroxide ( H2O2 ).The apoptosis rate under oxidative stress in PC-3 cells was evaluated by the flow cytometry.Results After transfection,the expression level of TAP gene was significantly higher than the wild type PC-3 cell line.The TAP mRNA expression level in the groups of hydrogen peroxide alone (2.457 ± 0.113 ) or hydrogen peroxide combined with 250 μmol/L BSO (3.643 ± 0.162) was significantly higher than in control group (0.721 ± 0.048 ) ( P< 0.01 ).The flow cytometry suggested that in control group,the apoptosis rate in PC-3 cells,PC-3-TAP cells,PC-3-vector cells was 2.42%,3.69% and 15.37% respectively; In the hydrogen peroxide-stimulated groups,the apoptosis rate was 7.56%,16.71% and 43.93%,respectively; In the group of BSO combined with hydrogen peroxide,the apoptosis rate was 13.73%,26.36% and 49.19%,respectively.Conclusion TAP gene was involved in the response of oxidative stress in prostate cancer cells,and could promote the apoptosis induced by oxidative stress. Key words: Prostate carcinoma; Oxidative stress; Tocopherol associated protein; Apoptosis