title: Lysophosphatidic acid upregulates vascular endothelial growth factor-C and tube formation in human endothelial cells through LPA(1/3), COX-2, and NF-kappaB activation- and EGFR transactivation-dependent mechanisms.
abstract: Lysophosphatidic acid (LPA) is a lipid bioactive mediator which binds to G-protein-coupled receptors and activates a variety of cellular functions. LPA modulates multiple behaviors in endothelial cells, including cell proliferation and migration, capillary-like tube formation in vitro, activation of proteases, interactions with leukocytes, and expressions of inflammation-related genes, thereby regulating vessel formation. LPA has been reported to modulate the angiogenesis process. However, the role of LPA in the lymphangiogenesis process has not been studied. In this study, we showed that LPA upregulated vascular endothelial growth factor-C (VEGF-C) mRNA expression in human umbilical vein endothelial cells (HUVECs) and subsequent endothelial cell tube formation in vitro and in vivo. These enhancement effects were LPA(1)- and LPA(3)-dependent and required cyclooxygenase-2 (COX-2), endothelial growth factor receptor (EGFR) transactivation and activation of nuclear factor kappaB (NF-kappaB). Moreover, LPA induced the protein expressions of the lymphatic markers, Prox-1, LYVE-1, and podoplanin, in HUVECs, and these enhancement effects were dependent on LPA(1) and LPA(3) activation and EGFR transactivation. Our results demonstrated that LPA might regulate VEGF-C and lymphatic marker expression in endothelial cells, which contributes to endothelial cell tube formation in vitro and in vivo, thus facilitating endothelial cell participation in the lymphangiogenesis process. This study clarifies the signaling mechanism of LPA-regulated VEGF-C expression and lymphatic marker expressions in endothelial cells, which suggest that LPA may be a suitable target for generating therapeutics against lymphangiogenesis and tumor metastasis.
authors.affiliation: Institute of Zoology, National Taiwan University, Taipei 106, Taiwan.
authors.forename: Chi-Iou
authors.initials: CI
authors.lastname: Lin
authors.forename: Chiung-Nien
authors.initials: CN
authors.lastname: Chen
authors.forename: Miao-Tzu
authors.initials: MT
authors.lastname: Huang
authors.forename: Shyh-Jye
authors.initials: SJ
authors.lastname: Lee
authors.forename: Chih-Hsin
authors.initials: CH
authors.lastname: Lin
authors.forename: Cheng-Chi
authors.initials: CC
authors.lastname: Chang
authors.forename: Hsinyu
authors.initials: H
authors.lastname: Lee
mesh_terms: D015415:Biomarkers / Q000378:metabolism; D002478:Cells, Cultured; D051546:Cyclooxygenase 2 / Q000378:metabolism*; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology; D042783:Endothelial Cells / Q000166:cytology / Q000187:drug effects / Q000201:enzymology*; D004789:Enzyme Activation / Q000187:drug effects; D018398:Homeodomain Proteins / Q000378:metabolism; D006801:Humans; D008246:Lysophospholipids / Q000494:pharmacology*; D008954:Models, Biological; D016328:NF-kappa B / Q000037:antagonists & inhibitors / Q000378:metabolism; D018919:Neovascularization, Physiologic / Q000187:drug effects*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering / Q000378:metabolism; D049368:Receptors, Lysophosphatidic Acid / Q000037:antagonists & inhibitors / Q000378:metabolism*; D040262:Receptors, Vascular Endothelial Growth Factor / Q000037:antagonists & inhibitors / Q000235:genetics; D015533:Transcriptional Activation / Q000187:drug effects; D025521:Tumor Suppressor Proteins / Q000378:metabolism; D015854:Up-Regulation / Q000187:drug effects*; D042582:Vascular Endothelial Growth Factor C / Q000235:genetics* / Q000378:metabolism; D000098551:Prospero-Related Homeobox 1 Protein
chemical_list: D015415:Biomarkers; D016861:Cyclooxygenase Inhibitors; D018398:Homeodomain Proteins; D008246:Lysophospholipids; D016328:NF-kappa B; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D049368:Receptors, Lysophosphatidic Acid; D025521:Tumor Suppressor Proteins; D042582:Vascular Endothelial Growth Factor C; D000098551:Prospero-Related Homeobox 1 Protein; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D040262:Receptors, Vascular Endothelial Growth Factor; C032881:lysophosphatidic acid