Study on the roles of SDF-1/CXCR4 axis in imatinib resistance of K562 cells co-cultured with the bone marrow stromal cells
	    		
		   		
		   			
		   		
	    	
    	 
    	10.3760/cma.j.issn.1008-1372.2014.10.013
   		
        
        	
        		- VernacularTitle:SDF-1/CXCR4轴在骨髓基质细胞共培养介导K562细胞伊马替尼耐药的作用研究
 
        	
        	
        	
        		- Author:
	        		
		        		
		        		
			        		Jigang WANG
			        		
			        		;
		        		
		        		
		        		
			        		Fan ZHOU
			        		
			        		;
		        		
		        		
		        		
			        		Yanqin LIU
			        		
			        		;
		        		
		        		
		        		
			        		Ying BAI
			        		
			        		;
		        		
		        		
		        		
			        		Jinghua LIU
			        		
			        		;
		        		
		        		
		        		
			        		Minyan LI
			        		
			        		
		        		
		        		
		        		
		        		
		        		
			        		
			        		
		        		
	        		
        		 
        	
        	
        	
        		- Publication Type:Journal Article
 
        	
        	
        		- Keywords:
        			
	        			
	        				
	        				
			        		
				        		Leukemia,myelogenous,chronic,BCR-ABL positive/drug therapy;
			        		
			        		
			        		
				        		Coculture techniques;
			        		
			        		
			        		
				        		Chemokine CXCL12;
			        		
			        		
			        		
				        		Receptors,CXCR4;
			        		
			        		
			        		
				        		Bone marrow cells;
			        		
			        		
			        		
				        		K562 cells;
			        		
			        		
			        		
				        		Drug tolerance;
			        		
			        		
			        		
				        		Piperazines/therapeutic use;
			        		
			        		
			        		
				        		Pyrimidines/therapeutic use
			        		
			        		
	        			
        			
        		
 
        	
            
            
            	- From:
	            		
	            			Journal of Chinese Physician
	            		
	            		 2014;16(10):1353-1357
	            	
            	
 
            
            
            	- CountryChina
 
            
            
            	- Language:Chinese
 
            
            
            	- 
		        	Abstract:
			       	
			       		
				        
				        	Objective To investigate influences of co-culture with the bone marrow stromal cells (BMSCs) on imatinib sensitivity,and the role of stromal cell-derived factor-1 (SDF-1)/chemokine receptor 4 (CXCR4) axis in imatinib resistance of K562 cells in the co-culture model.Methods The model was constructed by co-culturing K562 cells with BMSCs isolated and cultured from the patients with chronic myeloid leukemia.The apoptosis rate and the CXCR4 expressing rate of the K562 cells exposed to 0.5 μmol/L imatinib for 72 hours were detected by fluorescent-activated cell scanning (FACS) machine.The K562 cells were exposed to 0.5 μmol/L imatinib for 4 hours,and labelled by calckin-AM fluorescent labeling sytem.The adhesion rate of the K562 cells co-cultured with BMSCs for 24 hours was calculated with fluorescence intensity.The IC50 value of K562 cells exposed to imatinib was detected by methyl thiazolyl tetrazolium (MTT) assay while the SDF-1/CXCR4 axis was blocked by 10 μg/ml monoclonal antibody of CXCR4.Results The apoptosis rate of K562 cells exposed to 0.5 μmol/L imatinib for 72 hours in co-culture group and suspension culture group was (15.48 ±4.17) % and (32.01 ±6.83) %,respectively.The apoptosis rates of K562 cells in the two groups were significantly different (t =5.587,P =0.001).For the co-culture group,the CXCR4 expressing rates of K562 cells unexposed and exposed to 0.5 μmol/L imatinib for 72 hours were (20.31 ± 3.76) % (suspension cultured:11.28% ± 3.44%) and (53.64 ± 5.35) % (suspension cultured:25.34% ± 3.21%),respectively.Those results showed that co-culture with BMSCs and exposure to imatinib induced the K562 cells to express CXCR4.The adhesion rates of the K562 cells to the BMSCs were elevated from (42.18 ± 6.17) % to (68.97 ± 11.08) % when the K562 cells were exposed to 0.5 μmol/L imatinib for 4 hours.The IC50 values of block group (the SDF-1/CXCR4 axis was blocked by 10 μg/ml monoclonal antibody of CXCR4) and unblock group were (0.68 ± 0.04) μmol/L and (1.27 ± 0.05) μmol/L,respectively.The IC50 values of two groups were significantly different(t =4.869,P =0.001).Conclusions The K562 cells co-cultured with the BMSCs from the patients with chronic myeloid leukemia can obtain resistance to imatinib,which was related with that co-culture with the BMSCs and exposure to imatinib can induce the K562 cells to express CXCR4.To a certain extent,the imatinib resistance mediated by co-culture with BMSCs can be reversed by monoclonal antibody of CXCR4.