Overproduction of vascular endothelial growth factor related to von Hippel-Lindau tumor suppressor gene mutations and hypoxia-inducible factor-1 alpha expression in renal cell carcinomas. - Na,X.; Wu,G.; Ryan,C.K.; Schoen,S.R.; di'Santagnese,P.A.; Messing,E.M. (J Urol, 2003)