title: Impairment of breast cancer cell invasion by COX-2-specific inhibitor NS398: roles of CXCR4 and of uPA system.
abstract: Inhibition of cyclooxygenase-2 (COX-2) is known to impair cancer cell metastatic behaviour, but the mechanisms involved largely remain elusive. We aimed to analyse whether the antimetastatic effect of COX-2 inhibition in breast cancer cells could be explained by variations in the expression levels of chemokine receptor CXCR4, vascular endothelium growth factor (VEGF) and UPA/UPAR components of the urokinase plasminogen activator system (uPAR). Breast cancer cell line MDA-MB-231 was exposed to COX-2-specific inhibitor NS398. Experimental data were assessed using Matrigel invasion tests, qRT-PCR, ELISA, flow cytometry and MTT test. Exposure to NS398 had no major effect on cell viability, apoptosis or VEGF production. Cell invasion was significantly decreased with reductions ranging from of 3.6% with 10 μM NS398 to 81.04% with 100 μM NS398. CXCR4 membrane expression was significantly reduced by 18% (P < 0.05) when cells were treated with 100 μM of NS398 for 72 h. UPA mRNA levels were significantly reduced to 78 and 63% after treatment with 10 μM NS398 for 48 and 72 h, respectively (P < 0.05). UPAR mRNA levels also decreased with mild NS398 concentrations, reaching the lowest level of 56% with 50 μM of NS398 for 48 h (P < 0.05). With NS398 higher concentrations, UPAR and UPA expression levels increased. According to our results, impairment of expression of CXCR4, UPA and UPAR differentially contribute to the antimetastatic effect of COX-2 inhibitors depending on drug concentration.
authors.affiliation: Department of Medical Genetics and CIMAGO, Faculty of Medicine, University of Coimbra, Pólo III, Azinhaga de Santa Comba, Celas, 3000-548 Coimbra, Portugal. hsilva@fmed.uc.pt
authors.forename: Henriqueta Coimbra
authors.initials: HC
authors.lastname: Silva
authors.forename: Vera
authors.initials: V
authors.lastname: Alves
authors.forename: Luis Alcides Mesquita
authors.initials: LA
authors.lastname: Nogueira
authors.forename: Manuel Santos
authors.initials: MS
authors.lastname: Rosa
authors.forename: Lina
authors.initials: L
authors.lastname: Carvalho
authors.forename: Fernando
authors.initials: F
authors.lastname: Regateiro
mesh_terms: D017209:Apoptosis; D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000187:drug effects*; D051546:Cyclooxygenase 2 / Q000378:metabolism; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D009361:Neoplasm Invasiveness / Q000473:pathology; D009578:Nitrobenzenes / Q000494:pharmacology*; D060888:Real-Time Polymerase Chain Reaction; D019718:Receptors, CXCR4 / Q000378:metabolism*; D055293:Receptors, Urokinase Plasminogen Activator / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013449:Sulfonamides / Q000494:pharmacology*; D014568:Urokinase-Type Plasminogen Activator / Q000378:metabolism*
chemical_list: C527276:CXCR4 protein, human; D016861:Cyclooxygenase Inhibitors; D009578:Nitrobenzenes; D019718:Receptors, CXCR4; D055293:Receptors, Urokinase Plasminogen Activator; D013449:Sulfonamides; C080955:N-(2-cyclohexyloxy-4-nitrophenyl)methanesulfonamide; D051546:Cyclooxygenase 2; D014568:Urokinase-Type Plasminogen Activator