title: Pseudomonas aeruginosa lipopolysaccharide induction of keratinocyte proliferation, NF-kappa B, and cyclin D1 is inhibited by indomethacin.
abstract: NF-kappaB is activated during acute inflammatory states as well as in other injury response disease states. Several pathologic states in squamous tissue injury response are characterized by increased squamous proliferation. This study was performed to investigate the hypothesis that Pseudomonas aeruginosa LPS is able to activate a proliferative phenotype in squamous cells via NF-kappaB induction and that this NF-kappaB-mediated response may be abrogated with the classic anti-inflammatory agent indomethacin. EMSA, luciferase reporter gene experiments, Western blots, and cellular proliferation assays were performed in normal and transformed human keratinocytes after stimulation with P. aeruginosa LPS. EMSA and luciferase reporter gene assays showed a 3- to 5-fold induction of active NF-kappaB in human keratinocyte cell lines after stimulation with P. aeruginosa LPS. The stimulation correlated with significantly increased cellular proliferation. As one potential mechanism for this increase in proliferation, an NF-kappaB-specific activation of cyclin D1 was observed. Both the NF-kappaB induction and proliferation response were inhibited with indomethacin and in dominant negative stable transfection clones. P. aeruginosa LPS activates proliferation of human keratinocytes, potentially through the induction of NF-kappaB and cyclin D1. These findings suggest that bacterial components can contribute to proliferative disease states in squamous epithelium through NF-kappaB activation.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Molecular Oncology Program, University of Minnesota, Minneapolis, MN 55455, USA.
authors.forename: Diego
authors.initials: D
authors.lastname: Preciado
authors.forename: Emiro
authors.initials: E
authors.lastname: Caicedo
authors.forename: Rajat
authors.initials: R
authors.lastname: Jhanjee
authors.forename: Rob
authors.initials: R
authors.lastname: Silver
authors.forename: George
authors.initials: G
authors.lastname: Harris
authors.forename: Steven K
authors.initials: SK
authors.lastname: Juhn
authors.forename: Dan I
authors.initials: DI
authors.lastname: Choo
authors.forename: Frank
authors.initials: F
authors.lastname: Ondrey
mesh_terms: D015153:Blotting, Western; D002461:Cell Line, Transformed; D049109:Cell Proliferation / Q000187:drug effects*; D002999:Clone Cells; D019938:Cyclin D1 / Q000037:antagonists & inhibitors* / Q000096:biosynthesis / Q000235:genetics; D017930:Genes, Reporter; D006131:Growth Inhibitors / Q000494:pharmacology; D006801:Humans; D020672:I-kappa B Proteins / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D007213:Indomethacin / Q000494:pharmacology*; D015603:Keratinocytes / Q000166:cytology* / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism; D008070:Lipopolysaccharides / Q000037:antagonists & inhibitors / Q000276:immunology*; D008156:Luciferases / Q000235:genetics; D000072000:NF-KappaB Inhibitor alpha; D016328:NF-kappa B / Q000037:antagonists & inhibitors* / Q000096:biosynthesis / Q000378:metabolism; D011550:Pseudomonas aeruginosa / Q000276:immunology*; D013778:Tetrazolium Salts / Q000032:analysis; D013844:Thiazoles / Q000032:analysis; D013936:Thymidine / Q000378:metabolism; D014162:Transfection
chemical_list: D006131:Growth Inhibitors; D020672:I-kappa B Proteins; D008070:Lipopolysaccharides; D016328:NF-kappa B; C000606204:NFKBIA protein, human; D013778:Tetrazolium Salts; D013844:Thiazoles; D019938:Cyclin D1; D000072000:NF-KappaB Inhibitor alpha; D008156:Luciferases; C022616:thiazolyl blue; D013936:Thymidine; D007213:Indomethacin