Experimental Study On Inhibitory Effect Of Trichostatin A And Bacillus Calmette-Guerinon Growth Of Bladder Cancer Cells

Objective:To investigate the influence of histone deacetylase (HDAC) Inhibitor Trichostatin A and Bacillus Calmette-Guerin (BCG)on the growth of bladder cancer cell in vitro, and explore the mechanism involved. Methods:A human bladder cancer cell line, BIU-87, was treated with different concentrations of Trichostatin A (100 nmol/L,200nmol/L,400nmol/L,800nmol/L) and BCG(0.15 mg/ml,0.3 mg/ml,0.6mg/ml,1.2 mg/ml). The antitumor effect of HDAC inhibitor Trichostatin A and BCG on BIU-87 bladder cancer cells in vitro was measured with respect to cell morphology, cell cycle, apoptosis, gene expression. After treatment, cell growth was measured by MTT assay. cell cycle and cell apoptosis changes were examined by means of flow cytometry (FCM). mRNA expression of p27KIP1,cyclin D1,Fas and XIAP was assessed by differential reverse transcription-polymerase chain reaction. The expressional level of p27KIP1,cyclin D1,Fas and XIAP protein was detected by Western blot. Results: Trichostatin A and Bacillus Calmette-Guerin significantly inhibited the proliferation of bladder cancer cell in a time-and dose-dependent manner (p<0.05). When administered in moderate or higher concentration, TSA combined with BCG demonstrated synergic effect. Flow cytometry showed that the cells were blocked at G0-G1 phase (p<0.05).Percentage of G0-G1 phase cell increased from (44.39±3.42)% to (75.37±4.13)%(TSA) and to (65.59±3.43)%(BCG) and (87.97±3.53)%(TSA+BCG).After BIU-87 cells were treated with Trichostatin A and BCG, apoptotic cells of typical morphological changes appeared and apoptotic ratio was increased considerably (p<0.05). After treatment with TSA and BCG,total apoptosis was increased from 14.88±1.34(BCG) and 28.15±2.13(TSA)to 61.06±4.29(TSA+BCG)(P<0.01) and expressions of p27KIP1,cyclin D1,Fas and XIAP were up-regulated or down-regulated respectively by means of reverse transcription-polymerase chain reaction and western blot. Conclusion:HDAC inhibitor has antitumor effect on bladder cancer in vitro through inducing cell apoptosis and inhibiting cell proliferation, which might be related to the regulation of expression of genes(p27KIP1,cyclin D1,Fas and XIAP)involved. TSA combined with BCG is promising to be used as a new antitumor method to treat bladder neoplasms.