title: The NF-κB pathway mediates lysophosphatidic acid (LPA)-induced VEGF signaling and cell invasion in epithelial ovarian cancer (EOC).
abstract: OBJECTIVE
  Our previous report has implicated the involvement of VEGF-VEGFR-2 h signaling in LPA-induced EOC invasion. However, the mechanism by which LPA regulates VEGF and VEGFR-2 expression remains to be elucidated. In the present study, we systematically examined the signal transduction pathways activated by LPA and further evaluated whether LPA's effect on VEGF-VEGFR-2 signaling and EOC invasion was mediated by the activation of NF-κB pathway.
  
  
  METHODS
  Using a signal transduction PathwayFinder PCR array, we examined the expression change of 86 key genes representing 18 signal transduction pathways in DOV13 and SKOV3 cells upon LPA (20 μM) treatment. We also used quantitative PCR, Western blotting and ELISA to evaluate the effect of NF-κB pathway inhibition on VEGF(121), VEGF(165) and VEGFR-2 mRNA and protein expression/secretion with or without the presence of LPA (20 μM) in SKOV3. Cell invasion under various treatment conditions was assessed by Matrigel invasion assay and MMP-2 secretion was detected by gelatin zymography.
  
  
  RESULTS
  Our results showed that in both DOV13 and SKOV3, several of the NF-κB pathway components, such as TNF, are consistently activated by LPA stimulation. In addition, treatment with an NF-κB pathway activation inhibitor, at 10 μM, significantly decreased LPA-induced VEGF(121), VEGF(165) and VEGFR-2 mRNA expression and VEGF secretion, as well as LPA-induced SKOV3 invasion (p<0.05). When combined with an EGFR inhibitor, NF-κB pathway inhibition exhibited a significantly stronger effect than used alone (p<0.05) on reducing LPA-induced VEGF secretion and cell invasion. Additionally, NF-κB inhibition also decreased LPA-induced MMP-2 secretion and MMP-1 expression (p<0.05).
  
  
  CONCLUSIONS
  These results suggest that the NF-κB pathway plays an important role in LPA-induced VEGF signaling and EOC invasion and targeting this pathway may reveal potential therapeutic options for metastatic EOC.
authors.affiliation: Department of Obstetrics, Gynecology and Reproductive Sciences, Mount Sinai School of Medicine, New York, NY 10029, USA.
authors.forename: Sonia
authors.initials: S
authors.lastname: Dutta
authors.forename: Feng-qiang
authors.initials: FQ
authors.lastname: Wang
authors.forename: Hai-shan
authors.initials: HS
authors.lastname: Wu
authors.forename: Thayer J
authors.initials: TJ
authors.lastname: Mukherjee
authors.forename: David A
authors.initials: DA
authors.lastname: Fishman
mesh_terms: D000077216:Carcinoma, Ovarian Epithelial; D045744:Cell Line, Tumor; D066246:ErbB Receptors / Q000037:antagonists & inhibitors / Q000378:metabolism; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006801:Humans; D008246:Lysophospholipids / Q000494:pharmacology*; D020782:Matrix Metalloproteinases / Q000378:metabolism; D016328:NF-kappa B / Q000037:antagonists & inhibitors / Q000378:metabolism*; D009361:Neoplasm Invasiveness; D009375:Neoplasms, Glandular and Epithelial / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D010051:Ovarian Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D015398:Signal Transduction / Q000187:drug effects / Q000235:genetics; D015854:Up-Regulation / Q000187:drug effects; D042461:Vascular Endothelial Growth Factor A / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism
chemical_list: D008246:Lysophospholipids; D016328:NF-kappa B; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A; D066246:ErbB Receptors; D040301:Vascular Endothelial Growth Factor Receptor-2; D020782:Matrix Metalloproteinases; C032881:lysophosphatidic acid