title: Regulation of vascular endothelial cell growth factor expression in mouse mammary tumor cells by the EP2 subtype of the prostaglandin E2 receptor.
abstract: Prostaglandin E(2) (PGE(2)), a major metabolite of the cyclooxygenase pathway in the mammary gland, induces angiogenesis during mammary tumor progression. To better define the molecular mechanisms involved, we examined the role of the G protein-coupled receptors (GPCR) for PGE(2) in mammary tumor cell lines isolated from MMTV-cyclooxygenase-2 (COX-2) transgenic mice. Expression of the EP2 subtype of the PGE(2) receptor was correlated with the tumorigenic phenotype and the ability to induce vascular endothelial growth factor (VEGF). Overexpression of EP2 by adenoviral transduction into EP2-null cells resulted in the induction of VEGF expression in response to PGE(2) and CAY10399, an EP2 receptor agonist. The induction of VEGF by the EP2 receptor did not require the hypoxia inducible factor (HIF)-1alpha pathway, MAP kinase pathway, or phosphoinositide-3-kinase/Akt pathway, but required the cAMP/protein kinase A pathway. These results suggest that EP2 receptor is a critical element for PGE(2) mediated VEGF induction in mouse mammary tumor cells.
authors.affiliation: Center for Vascular Biology, Department of Cell Biology, University of Connecticut Health Center, Farmington, 06030-3501, USA.
authors.forename: Sung-Hee
authors.initials: SH
authors.lastname: Chang
authors.forename: Catherine H
authors.initials: CH
authors.lastname: Liu
authors.forename: Ming-Tao
authors.initials: MT
authors.lastname: Wu
authors.forename: Timothy
authors.initials: T
authors.lastname: Hla
mesh_terms: D000818:Animals; D001483:Base Sequence; D015153:Blotting, Western; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism; D017931:DNA Primers; D005260:Female; D047468:Immunoprecipitation; D008325:Mammary Neoplasms, Experimental / Q000201:enzymology / Q000378:metabolism* / Q000473:pathology; D051379:Mice; D018078:Receptors, Prostaglandin E / Q000378:metabolism*; D058307:Receptors, Prostaglandin E, EP2 Subtype; D014407:Tumor Cells, Cultured; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism*
chemical_list: D017931:DNA Primers; C545645:Ptger2 protein, mouse; D018078:Receptors, Prostaglandin E; D058307:Receptors, Prostaglandin E, EP2 Subtype; D042461:Vascular Endothelial Growth Factor A; D017868:Cyclic AMP-Dependent Protein Kinases