Effect of Regulating A20 Expression on NF-κB Expression and Biological Characteristics of Jurkat Cells

Abstract

To explore the effect of regulating A20 expression on NF-κB and biological characteristics of Jurkat cells with glucocorticoid (GC) resistance. CCRF CEM and Jurkat cells were treated with dexamethasone (DEX) at concentrations of 100、10、1、0.1、0.01 and 0.001 μmol/L, and cultured for 24、48 and 72 h. The proliferation inhibition rate of Jurkat cell was detected by CCK-8. A20 plasmid was constructed, A20-siRNA was designed and synthesized, and transfected into Jurkat cells by liposome. CCK-8 was used to detect the proliferation rates of Jurkat cells in different concentrations of DEX group, DEX combined with A20 plasmid group and A20-siRNA group. The mRNA expression level of NF-κB was detected by RT-qPCR, the protein expression level of NF-κB was detected by Western blot, and the apoptosis of Jurkat cells was examined by flow cytometry. The inhibitory effects of DEX at different concentrations on the growth of CCRF CEM cells were time-dependent (r=0.984, P＜0.05) and concentration-dependent (r=0.966, P＜0.05). At the point of 24 hour, the IC50 approached 1 μmol/L in CCRF CEM cells. Great large differences began to appear between 1 and 10 μmol/L, the proliferation rate of Jurkat cells treated with 1 μmol/L DEX did not show a significant change. Therefore, 1 μmol/L was selected as control group. The cell proliferation rate of A20 plasmid transfection combined with different concentrations of DEX group was lower than that of DEX group and A20-siRNA combined with DEX group. After transfection of A20 plasmid, the expression level of NF-κB was significantly lower than that of control group (P＜0.05), and the apoptotic rate was significantly higher than that of control group (P＜0.05). After transfection of Jurkat cells with A20-siRNA, the expression level of NF-κB was significantly higher than that of control group (P＜0.05). The apoptotic rate of cells in A20-siRNA group was not significantly changed (P＞0.05). Jurkat cells are resistant to DEX. A20 overexpression combined with DEX can increase sensitivity of Jurkat cells with GC resistance and decrease the proliferation rate of Jurkat cells, down-regulate the expression level of NF-κB and promote the apoptosis of Jurkat cells.