title: Contribution of reactive oxygen species to migration/invasion of human glioblastoma cells U87 via ERK-dependent COX-2/PGE(2) activation.
abstract: In the presence of 12-O-tetradecanoylphorbol-13-acetate (TPA) stimulation, an increase in the migration/invasion of U87 glioblastoma cells was detected by a wound healing assay, transwell analysis, and spheroid formation assay by inducing matrix metalloproteinase-9 (MMP-9) enzyme activity via a gelatin zymographic analysis. A dose- and time-dependent increase in cyclooxygenase-2 (COX-2) gene expression with elevated prostaglandin E(2) (PGE(2)) production was identified in TPA- but not in 4alpha-TPA (a respective inactive compound)-treated U87 cells TPA-induced migration/invasion was significantly blocked by adding the COX-2-specific inhibitor, NS398, through a reduction in PGE(2) production. Data from the pharmacological studies using specific chemical inhibitors showed that activation of protein kinase C (PKC) and extracellular signal-regulated kinases (ERKs) was involved in TPA-induced migration/invasion, COX-2 protein expression, and MMP-9 activation. Stimulation of intracellular peroxide production by TPA was detected by a DCHF-DA assay, and the addition of superoxide dismutase (SOD) or tempol significantly inhibited TPA-induced migration/invasion and COX-2 protein expression accompanied by a decrease in peroxide production. An increase in NADPH oxidase activity by TPA was examined, and TPA-induced migration/invasion was blocked by adding DPI, an NADPH oxidase inhibitor. Additionally, the natural flavonoids quercetin (QE), baicalein (BE), and myricetin (ME) effectively blocked TPA-induced migration/invasion while simultaneously inhibiting COX-2/PGE(2) production, MMP-9 enzyme activity, and peroxide production in U87 cells. The contribution of ROS production to the migration/invasion of U87 glioblastoma cells via ERK-activated COX-2/PGE(2) and MMP-9 induction was first investigated here, and agents such as QE, BE, and ME with the ability to block these events possess the potential to be developed for use against migration/invasion by glioblastomas.
authors.affiliation: Department of Neurosurgery, Taipei Medical University-Shuang Ho Hospital, Taipei, Taiwan.
authors.forename: Wen-Ta
authors.initials: WT
authors.lastname: Chiu
authors.forename: Shing-Chuan
authors.initials: SC
authors.lastname: Shen
authors.forename: Jyh-Ming
authors.initials: JM
authors.lastname: Chow
authors.forename: Cheng-Wei
authors.initials: CW
authors.lastname: Lin
authors.forename: Ling-Tin
authors.initials: LT
authors.lastname: Shia
authors.forename: Yen-Chou
authors.initials: YC
authors.lastname: Chen
mesh_terms: D045744:Cell Line, Tumor; D002465:Cell Movement / Q000187:drug effects / Q000502:physiology; D051546:Cyclooxygenase 2 / Q000378:metabolism*; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology; D015232:Dinoprostone / Q000378:metabolism*; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism*; D005909:Glioblastoma / Q000188:drug therapy / Q000503:physiopathology*; D006801:Humans; D042541:Intracellular Space / Q000187:drug effects / Q000502:physiology; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism*; D019255:NADPH Oxidases / Q000037:antagonists & inhibitors / Q000378:metabolism; D010545:Peroxides / Q000378:metabolism; D011493:Protein Kinase C / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism*; D015398:Signal Transduction; D013997:Time Factors
chemical_list: D016861:Cyclooxygenase Inhibitors; D010545:Peroxides; D017382:Reactive Oxygen Species; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human; D019255:NADPH Oxidases; D011493:Protein Kinase C; D048049:Extracellular Signal-Regulated MAP Kinases; D020780:Matrix Metalloproteinase 9; D015232:Dinoprostone