Effect of SIRT1 gene silencing on radiosensitivity of diffuse large B-cell lymphoma cells / 中华放射肿瘤学杂志

ABSTRACT

Objective To explore the effect of SIRT1 gene silencing on the radiosensitivity of diffuse large B-cell lymphoma (DLBCL) cells.Methods Immunohistochemistry was used to measure the protein expression of SIRT1 in DLBCL tissues.Western blot was used to measure the expression of SIRT1 in DLBCL cell lines (OCI-Ly3,SU-DHL-2,and SU-DHL-4) and the immortalized B cell line HMy2.CIR.After SU-DHL-4 cells were transfected with si-SIRT1 and si-NC using Lipofectamine 2000,the expression of SIRT1 was determined by Western blot.MTT assay and colony-forming assay were used to assess the cell growth and colony formation ability of SU-DHL-4 cells treated with radiation.The group t-test or univariate analysis of variance was used for comparison between groups.Results The expression rate of SIRT1 in DLBCL tissues was 72.6%(103/140),which was significantly higher than that in reactive lymphoid hyperplasia (RLH) tissues (26.5%,8/25)(P=0.001).The SIRT1 expression was significantly higher in DLBCL cells than in HMy2.CIR cells (P=0.020).After SIRT1 gene silencing by si-SIRT1,the expression of SIRT1 was significantly reduced in SU-DHL-4 cells (P=0.008).Besides,SIRT1 gene silencing significantly reduced the growth rate and colony formation ability of SU-DHL-4 cells treated with radiation (P=0.030).Conclusions SIRT1 gene silencing enhances the radiosensitivity of DLBCL cells,providing a novel target for the radiotherapy of DLBCL.