MicroRNA-524-5p increases cisplatin-sensitivity of gastric cancer cells by targeting SOX9 gene 
	    		
		   		
		   			
		   		
	    	
    	 
    	10.3781/j.issn.1000-7431.2019.11.230
   		
        
        	
        	
        	
        		- Author:
	        		
		        		
		        		
			        		Guoan HUA
			        		
			        		
			        		
			        			1
			        			
			        		
			        		
			        		
			        		
			        		
		        		
		        		
		        		
		        		
		        			
			        		
			        		Author Information
			        		
		        		
		        		
			        		
			        		
			        			1. Department of Digestive Medicine, Guangming Chinese Medicine Hospital of Pudong New Area
			        		
		        		
	        		
        		 
        	
        	
        	
        		- Publication Type:Journal Article
 
        	
        	
        		- Keywords:
        			
	        			
	        				
	        				
			        		
				        		Cisplatin;
			        		
			        		
			        		
				        		Drug resistance;
			        		
			        		
			        		
				        		MicroRNA-524-5p;
			        		
			        		
			        		
				        		Neoplasm;
			        		
			        		
			        		
				        		SOX transcription factors;
			        		
			        		
			        		
				        		Stomach neoplasms
			        		
			        		
	        			
        			
        		
 
        	
            
            
            	- From:
	            		
	            			Tumor
	            		
	            		 2019;39(8):606-615
	            	
            	
 
            
            
            	- CountryChina
 
            
            
            	- Language:Chinese
 
            
            
            	- 
		        	Abstract:
			       	
			       		
				        
				        	 Objective: To investigate the mechanism of microRNA (miR)-524-5p mediating the effect of cisplatin in the treatment of gastric cancer. Methods: The level of miR-524-5p in gastric cancer tissues, the matched non-tumor tissues, cisplatin-resistant and parental gastric cancer cell lines was measured by real-time fluorescent quantitative PCR. The viability of cisplatin-resistant gastric cancer SGC-7901 and MKN-45 cells transfected with miR-524-5p mimics or the control RNA was detected by CCK-8 method. The expression of SRY-related high mobility group-box gene 9 (SOX9), a targeting protein of miR-524-5p, was identified by luciferase reporter assay and Western blotting. The “rescue” assay was used to explore the effect of SOX9 overexpression on the cisplatin-resistance of gastric cancer cells induced by miR-524-5p. Results: Compared with the normal gastric epithelial GES1 cells, the level of miR-524-5p in gastric cancer SGC-7901 and MKN-45 cells was significantly down-regulated (both P < 0.05); while the level of miR-524-5p in gastric cancer tissues was significantly lower than that in the adjacent non-tumor tissues (P < 0.05). After the treatment of cisplatin, the expression level of miR-524-5p in cisplatin-resistant gastric cancer SGC-7901 and MKN-45 cells was decreased as compared with the sensitive parental cells (both P< 0.05). After the transfection of miR-524-5p mimics, the sensitivity of cisplatin-resistant gastric cancer SGC-7901 and MKN-45 cells was significantly enhanced (both P< 0.05). Subsequently, SOX9 was identified as a functional target gene of miR-524-5p. Overexpression of SOX9 could counteract the chemosensitizing effect of miR-524-5p, in other words, the cisplatin-sensitivity of SGC-7901 and MKN-45 cells transfected with SOX9 overexpression plasmids and miR-524-5p mimics was significantly lower than that in single miR-524-5p mimics transfection group (both P< 0.05). Conclusion: The expression of miR-524-5p influences the sensitivity of human gastric cancer cells to cisplatin, suggesting that miR-524-5p has the potential to be a novel target for the treatment of chemoresistant gastric cancer patients.