The Effect Of HMGB 1 On Proliferation And Apoptosis Of Bladder Cancer Cells

Objective:To explore the effect of HMGB1 on proliferation and apoptosis of bladder cancer cells and the mechanism by detecting the expression of HMGB1 in bladder cancer cell lines (BIU-87,5637, T24, and EJ) and human normal bladder epithelial cells (SV-HUC-1).Methods:The first part:endogenous detection1. The expression of HMGB1 in bladder cancer cell lines (BIU-87,5637, T24, and EJ) and human normal bladder epithelial cells was detected by using bladder cancer tissue microarray technology.2. Bladder cancer cell lines (BIU-87,5637, T24, and EJ) and human normal bladder epithelial cells (SV-HUC-1) were used respect-ively. The level of mRNA for HMGB1 in bladder cancer cell lines (BIU-87,5637, T24,and EJ) and human normal bladder epithelial-cells was detected by using Quantitative Real-time PCR.The second part:function modeling1. Over-expression of HMGB1 and recombinant plasmids transfected bladder cancer cell lines (BIU-87 and T24)2. Targeted knockout plasmid of HMGB1 was designed and contrasted. Then bladder cancer cell lines (BIU-87 and T24) were transfe-cted with it. Finally, the stable cell lines were screened.3. The expression of HMGB1 protein in cell model was measured by using Western Blot.Different groups:Con, over-expression of NC, over-expressionof HMGB1, pTalen NC, and pTalen-HMGB1The third part:functional experiment1. The proliferation was detected by MTT.Different groups:The Con group, the scrambled siRNA group, the HMGB1 siRNA group, the NC group, the pTalen NC group, the pTalen-HMGB1 group.2. The metastasis and invasion was detected by Transwell.Different groups:Con, over-expression of NC, over-expression of HMGB1, pTalen NC, and pTalen-HMGB1.3. The apoptosis was detected by flow cytometry.Different groups:Con, over-expression of NC, over-expression of HMGB1, pTalen NC, and pTalen-HMGB1.Results:This study shows that the expression of HMGB1 protein in bladder cancer cell lines (BIU-87,5637, T24, and EJ) was higher than that in human normal bladder epithelial cells. After being transfected with HMGB1 siRNA, the growth of bladder cancer cell lines T24 and BIU-87 was inhibited. After being transfected with pTalen-HMGB1, the growth of bladder cancer cell lines T24 and BIU-87 was also inhibited. After being transfected with HMGB1 siRNA, the invasion ability of bladder cancer cell lines T24 and BIU-87 decreased. After being transfected with pTalen-HMGBl, the invasion abilityof bladder cancer cell lines T24 and BIU-87 also decreased. Afterbeing transfected with HMGB1 siRNA, the cell apoptosis rate increased. After being transfected with pTalen-HMGB1, the cell apoptosis rate also increased, but higher than HMGB1 siRNA group.Conclusions:1. The expression of HMGB1 in bladder cancer cell lines is higher than that in human normal bladder epithelial cells.2. The proliferation and invasion of bladder cancer cell lines is inhibited following HMGB1 knockout/silence.3. The apoptosis of bladder cancer cell lines is induced HMGB1 knockout/silence.4. The apoptosis of bladder cancer cell lines is induced by Bax/Bcl-2 following HMGB1 knockout/silence.