Influence of mifepristone on DNA repair genes and cisplatin sensitivity in human ovarian cancer drug-resistance cells
	    		
		   		
	    	
    	
    	
   		
        
        	
        		- VernacularTitle:米非司酮对卵巢上皮性癌耐药细胞DNA修复基因表达和顺铂敏感性的影响
 
        	
        	
        	
        		- Author:
	        		
		        		
		        		
			        		Guoyan LIU
			        		
			        		;
		        		
		        		
		        		
			        		Quanxin QU
			        		
			        		;
		        		
		        		
		        		
			        		Ruoran MI
			        		
			        		;
		        		
		        		
		        		
			        		Jing QI
			        		
			        		
		        		
		        		
		        		
		        		
		        		
			        		
			        		
		        		
	        		
        		 
        	
        	
        	
        		- Publication Type:Journal Article
 
        	
        	
        		- Keywords:
        			
	        			
	        				
	        				
			        		
				        		Ovarian neoplasms;
			        		
			        		
			        		
				        		Mifepristone;
			        		
			        		
			        		
				        		Drug resistance,neoplasm;
			        		
			        		
			        		
				        		DNA repair;
			        		
			        		
			        		
				        		Cisplatin
			        		
			        		
	        			
        			
        		
 
        	
            
            
            	- From:
	            		
	            			Chinese Journal of Obstetrics and Gynecology
	            		
	            		 2008;43(2):132-135
	            	
            	
 
            
            
            	- CountryChina
 
            
            
            	- Language:Chinese
 
            
            
            	- 
		        	Abstract:
			       	
			       		
				        
				        	Objective To study the changes of DNA repair genes and enhanced anti-tumor effect of cisplatin induced by mifepristone in human ovarian cancer drug resistance cells.Methods The alterations of cisplatin concentration producing 50%inhibition(IC50)in the COC1/DDP cell lines were examined by methyl thiazolyl tetrazolium(MTT)assay.RT-PCR and flow cytometry were used to analyze the changes of the mRNA of ERCC1,BRCA1,hMLH1 genes and cell cycle and apoptosis.Subcutaneous implantation of COC1/DDP was established in nude mice and the enhanced anti-tumor effect of cisplatin by mifepristone was observed in vivo.ResultsCisplatin IC50 values of COC1/DDP cell were decreased from(3.71±0.38)μg/ml to(3.18±0.46),(1.95±0.14),(0.64±0,18)μg/ml respectively when treated with 2.5,5.0,10.0 μmol/L mifepristone.Mifepristone could down-regulate the mRNA levels of ERCC1,BRCA1,hMLH1 genes and enhance G0/G1 phase block effect pf cisplatin,and 2.5,5.0,10.0 μmol/L mifepristone combined with cisplatin increased rate of cell apoptosis from 0.08%to 5.11%,9.13%and 12.24% respectively.The percentage of inhibition of xenograft tumor volume in combined treatment group was 70.1%,which was significantly different(P<0.05).Conclusion By down-regulating ERCC1,BRCA1,hMLH1 genes,blocking G0/G1 phase,and increasing apoptosis rate,mifepristone could enhance anti-tumor effect of cisplatin.