- Author:
	        		
		        		
		        		
			        		Songyi HAN
			        		
			        		
			        		
			        			1
			        			
			        		
			        		
			        		
			        		
			        		;
		        		
		        		
		        		
			        		Jeongsoon HUH
			        		
			        		;
		        		
		        		
		        		
			        		Wooseong KIM
			        		
			        		;
		        		
		        		
		        		
			        		Seongkeun JEONG
			        		
			        		;
		        		
		        		
		        		
			        		Do Sik MIN
			        		
			        		;
		        		
		        		
		        		
			        		Yunjin JUNG
			        		
			        		
		        		
		        		
		        		
			        		
			        		Author Information
			        		
 - Publication Type:Original Article ; Research Support, Non-U.S. Gov't
 - MeSH: Cell Line, Tumor; Epidermal Growth Factor/metabolism; Gene Expression Regulation, Neoplastic; Glioma/genetics/*metabolism; Humans; Hypoxia-Inducible Factor 1, alpha Subunit/genetics/metabolism; Phosphatidic Acids/*metabolism; Phospholipase D/genetics/*metabolism; *Signal Transduction; Transfection; Vascular Endothelial Growth Factor A/*metabolism
 - From:Experimental & Molecular Medicine 2014;46(12):e126-
 - CountryRepublic of Korea
 - Language:English
 - Abstract: Growth factor-stimulated phospholipase D (PLD) catalyzes the hydrolysis of phosphatidylcholine (PC), generating phosphatidic acid (PA) which may act as a second messenger during cell proliferation and survival. Therefore, PLD is believed to play an important role in tumorigenesis. In this study, a potential mechanism for PLD-mediated tumorigenesis was explored. Ectopic expression of PLD1 or PLD2 in human glioma U87 cells increased the expression of hypoxia-inducible factor-1alpha (HIF-1alpha) protein. PLD-induced HIF-1 activation led to the secretion of vascular endothelial growth factor (VEGF), a HIF-1 target gene involved in tumorigenesis. PLD induction of HIF-1alpha was significantly attenuated by 1-butanol which blocks PA production by PLD, and PA per se was able to elevate HIF-1alpha protein level. Inhibition of mTOR, a PA-responsive kinase, reduced the levels of HIF-1alpha and VEGF in PLD-overexpressed cells. Epidermal growth factor activated PLD and increased the levels of HIF-1alpha and VEGF in U87 cells. A specific PLD inhibitor abolished expression of HIF-1alpha and secretion of VEGF. PLD may utilize HIF-1-VEGF pathway for PLD-mediated tumor cell proliferation and survival.
 
            
