ABSTRACT
Objective@#To investigate the effect of silencing the high-mobility group box-1 protein (HMGB1) combined with docetaxel (DTX) on the proliferation and apoptosis of PCa cells and its possible action mechanism.@*METHODS@#The expression of HMGB1 mRNA in different PCa cell lines and normal prostatic epithelial cells was detected by RT-qPCR. The PC-3 cells were transfected with different HMGB1 small interfering RNAs (si-HMGB1, si-HMGB1-2 and si-HMGB1-3), and the silencing effect was detected. The effects of different concentrations of DTX on the proliferation of the PC-3 cells was determined by MTT. Then the PC-3 cells were randomly divided into five groups: control (conventional culture), si-HMGB1-NC (si-HMGB1-NC transfection), si-HMGB1 (si-HMGB1-3 transfection), DTX (20 nmol/L DTX), and si-HMGB1+DTX (si-HMGB1-3+20 nmol/L DTX transfection), followed by measurement of the survival rate of the cells by MTT, their apoptosis rate by flow cytometry, and the expressions of HMGB1, B-cell lymphoma-2 (Bcl-2) and Bcl-2-associated X (Bax) proteins in different groups by Western blot.@*RESULTS@#The expression of HMGB1 mRNA in the PC-3 cells was the highest and the lowest after transfection with si-HMGB1-3. DTX inhibited the proliferation of the PC-3 cells at various concentrations. Compared with the control group, the si-HMGB1 and DTX groups showed significantly decreased A values, cell survival rates and HMGB1 and Bcl-2 expressions, but increased cell apoptosis rates and Bax expressions (P < 0.05). In comparison with the si-HMGB1 and DTX groups, the si-HMGB1+DTX group exhibited a remarkably decreased A value, cell survival rate and Bcl-2 expression, but increased cell apoptosis and Bax expression. The expression of the HMGB1 protein was markedly lower in the si-HMGB1+DTX than in the DTX group (P < 0.05).@*CONCLUSIONS@#Silencing HMGB1 combined with DTX chemotherapy can inhibit the proliferation and promote the apoptosis of PCa cells, which may be attributed to its regulatory effect on the expressions of the Bcl-2 family-related proteins.、.