title: Activation of HGF/c-Met pathway contributes to the reactive oxygen species generation and motility of small cell lung cancer cells.
abstract: Small cell lung cancer (SCLC) is a difficult disease to treat and sometimes has overexpression or mutation of c-Met receptor tyrosine kinase. The effects of c-Met/hepatocyte growth factor (c-Met/HGF, ligand for c-Met) on activation of reactive oxygen species (ROS) was determined. HGF stimulation of c-Met-overexpressing H69 SCLC cells (40 ng/ml, 15 min) resulted in an increase of ROS, measured with fluorescent probe 2'-7'-dichlorofluorescein diacetate (DCFH-DA) or dihydroethidine (DHE) but not in c-Met-null H446 cells. ROS was increased in juxtamembrane (JM)-mutated variants (R988C and T1010I) of c-Met compared with wild-type c-Met-expressing cells. ROS was significantly inhibited by preincubation of SCLC cells with pyrrolidine dithiocarbamate (PDTC, 100 microM) and/or SU11274 (small molecule c-Met tyrosine kinase inhibitor, 2 microM) for 3 h. PDTC and SU11274 also abrogated the HGF proliferative signal and cell motility in a cooperative fashion. H(2)O(2) treatment of SCLC cells (over 15 min) led to phosphorylation of c-Met receptor tyrosine kinase and further upregulated downstream phosphorylation of phospho-AKT, ERK1/2, and paxillin in a dose-dependent manner (125 microM to 500 microM). c-Met is an important target in lung cancer, and the pathways responsible for ROS generation together may provide novel therapeutic intervention.
authors.affiliation: Section of Hematology/Oncology, Department of Medicine, University of Chicago, Chicago, Illinois 60637, USA.
authors.forename: Ramasamy
authors.initials: R
authors.lastname: Jagadeeswaran
authors.forename: Sujatha
authors.initials: S
authors.lastname: Jagadeeswaran
authors.forename: Vytas P
authors.initials: VP
authors.lastname: Bindokas
authors.forename: Ravi
authors.initials: R
authors.lastname: Salgia
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000494:pharmacology; D002289:Carcinoma, Non-Small-Cell Lung / Q000378:metabolism* / Q000473:pathology; D002455:Cell Division / Q000187:drug effects / Q000502:physiology; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000502:physiology; D002470:Cell Survival / Q000502:physiology; D015972:Gene Expression Regulation, Neoplastic; D017228:Hepatocyte Growth Factor / Q000378:metabolism*; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism; D007211:Indoles / Q000494:pharmacology; D008175:Lung Neoplasms / Q000378:metabolism* / Q000473:pathology; D009115:Muridae; D010766:Phosphorylation; D010879:Piperazines / Q000494:pharmacology; D011392:Proline / Q000031:analogs & derivatives / Q000494:pharmacology; D019859:Proto-Oncogene Proteins c-met / Q000235:genetics / Q000378:metabolism*; D017382:Reactive Oxygen Species / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology; D013449:Sulfonamides / Q000494:pharmacology; D013859:Thiocarbamates / Q000494:pharmacology; D014443:Tyrosine / Q000378:metabolism
chemical_list: C478479:((3Z)-N-(3-chlorophenyl)-3-((3,5-dimethyl-4-((4-methylpiperazin-1-yl)carbonyl)-1H-pyrrol-2-yl)methylene)-N-methyl-2-oxo-2,3-dihydro-1H-indole-5-sulfonamide); D000975:Antioxidants; D007211:Indoles; D010879:Piperazines; D017382:Reactive Oxygen Species; D013449:Sulfonamides; D013859:Thiocarbamates; C066229:prolinedithiocarbamate; D014443:Tyrosine; D017228:Hepatocyte Growth Factor; D011392:Proline; D006861:Hydrogen Peroxide; D019859:Proto-Oncogene Proteins c-met