title: 12(S)-HETE promotes tumor-cell adhesion by increasing surface expression of alpha V beta 3 integrins on endothelial cells.
abstract: The present work was undertaken to investigate the regulatory role of 12(S)-HETE, a lipoxygenase metabolite of arachidonic acid, in the surface expression of alpha v beta 3 integrin receptors in endothelial cells (rat aortic endothelial cells, or RAEC). Several monoclonal and polyclonal antibodies localized alpha v beta 3 in focal adhesions in both subconfluent and post-confluent RAEC. RAEC alpha v beta 3 integrins were further characterized by immunoblotting and immunoprecipitation. 12(S)-HETE, but not 12(R)-HETE or other lipoxygenase-derived hydroxy fatty acids, induced a dose-dependent increase in alpha v beta 3 surface expression in RAEC, which was antagonized by prostacyclin or its analog iloprost as well as by 13-HODE, a 15-lipoxygenase product of linoleic acid. 12(S)-HETE promoted RAEC adhesion to vitronectin, an effect inhibited by antibodies against alpha v beta 3. 12(S)-HETE also promoted tumor-cell (W256 carcinosarcoma) adhesion to vitronectin, which was inhibited by various antibodies against alpha IIb beta 3 but not by an antibody against alpha v. W256 adhesion to 12(S)-HETE-treated RAEC demonstrated a significant increase, which was inhibited by anti-alpha v, -beta 3, or -alpha v beta 3 antibodies and by 13-HODE. Western blotting, immunoprecipitation and reverse transcription-polymerase chain reaction indicated that W256 carcinosarcoma cells expressed alpha IIb beta 3 integrins but not alpha v beta 3. The results suggest that the lipoxygenase metabolites [i.e., 12(S)-HETE and 13-HODE] play a significant role in modulating tumor-cell interactions with endothelium by enhancing endothelial cell integrin (e.g., alpha v beta 3) expression.
authors: Department of Radiation Oncology, Wayne State University, Detroit, MI 48202.
authors: D G
authors: DG
authors: Tang
authors: I M
authors: IM
authors: Grossi
authors: Y Q
authors: YQ
authors: Chen
authors: C A
authors: CA
authors: Diglio
authors: K V
authors: KV
authors: Honn
mesh_terms: D019377:12-Hydroxy-5,8,10,14-eicosatetraenoic Acid; D008841:Actin Cytoskeleton / Q000378:metabolism; D000818:Animals; D001483:Base Sequence; D015153:Blotting, Western; D002279:Carcinoma 256, Walker / Q000473:pathology*; D002448:Cell Adhesion / Q000187:drug effects; D002451:Cell Compartmentation; D002462:Cell Membrane / Q000378:metabolism; D004730:Endothelium, Vascular / Q000166:cytology* / Q000378:metabolism; D015870:Gene Expression; D006893:Hydroxyeicosatetraenoic Acids / Q000494:pharmacology*; D066298:In Vitro Techniques; D016023:Integrins / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D009838:Oligodeoxyribonucleotides / Q000737:chemistry; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats
chemical_list: D006893:Hydroxyeicosatetraenoic Acids; D016023:Integrins; D009838:Oligodeoxyribonucleotides; D012333:RNA, Messenger; D019377:12-Hydroxy-5,8,10,14-eicosatetraenoic Acid