title: ERK2 but not ERK1 mediates HGF-induced motility in non-small cell lung carcinoma cell lines.
abstract: Aberrant signalling of receptor tyrosine kinases (RTKs), such as c-Met, the receptor for hepatocyte growth factor (HGF), has been implicated in the oncogenesis of various tumours including non-small cell lung carcinoma (NSCLC). Through its pro-migratory properties, c-Met has been implicated specifically in the process of tumour metastasis, demanding a better understanding of the underlying signalling pathways. Various players downstream of c-Met have been well characterised, including the extracellular-signal-regulated kinases (ERKs) 1 and 2. In a small interfering RNA (siRNA)-based high-throughput wound healing screen performed in A549 lung carcinoma cells, we identified ERK2 but not ERK1 as a strong mediator of HGF-induced motility. This finding was confirmed in several NSCLC cell lines as well as in HeLa cells. One known substrate for ERK kinases in cell migration, the focal adhesion protein paxillin, was also one of the hits identified in the screen. We demonstrate that HGF stimulation results in a time-dependent phosphorylation of paxillin on serine 126, a process that can be blocked by inhibition of the ERK1/2 upstream kinase mitogen-activated protein kinase/ERK kinase 1 (MEK1) or inhibition of glycogen synthase kinase 3 (GSK3). Further, we show that paxillin turnover at focal adhesions is increased upon stimulation by HGF, an effect that is dependent on serine residues 126 (GSK3 site) and 130 (ERK site) within paxillin. In line with the isoform-specific requirement of ERK2 for HGF-mediated migration in lung tumour cell models, ERK2 but not ERK1 is shown to be responsible for paxillin serine 126 phosphorylation and its increased turnover at focal adhesions.
authors.affiliation: London Research Institute, 44 Lincoln's Inn Fields, London WC2A 3LY, UK. s.kermorgant@qmul.ac.uk
authors.forename: Simone
authors.initials: S
authors.lastname: Radtke
authors.forename: Mina
authors.initials: M
authors.lastname: Milanovic
authors.forename: Carine
authors.initials: C
authors.lastname: Rossé
authors.forename: Manu
authors.initials: M
authors.lastname: De Rycker
authors.forename: Sylvie
authors.initials: S
authors.lastname: Lachmann
authors.forename: Andrew
authors.initials: A
authors.lastname: Hibbert
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Kermorgant
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Parker
mesh_terms: D002289:Carcinoma, Non-Small-Cell Lung / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D002465:Cell Movement; D022001:Focal Adhesions / Q000235:genetics / Q000378:metabolism; D038362:Glycogen Synthase Kinase 3 / Q000235:genetics / Q000378:metabolism; D006367:HeLa Cells; D017228:Hepatocyte Growth Factor / Q000378:metabolism* / Q000494:pharmacology; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D048369:MAP Kinase Kinase 1 / Q000235:genetics / Q000378:metabolism; D020935:MAP Kinase Signaling System; D019950:Mitogen-Activated Protein Kinase 1 / Q000235:genetics / Q000378:metabolism*; D048052:Mitogen-Activated Protein Kinase 3 / Q000235:genetics / Q000378:metabolism*; D051419:Paxillin / Q000235:genetics / Q000378:metabolism; D019859:Proto-Oncogene Proteins c-met / Q000235:genetics / Q000378:metabolism
chemical_list: C066855:HGF protein, human; C496061:PXN protein, human; D051419:Paxillin; D017228:Hepatocyte Growth Factor; D019859:Proto-Oncogene Proteins c-met; C535150:MAPK1 protein, human; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D038362:Glycogen Synthase Kinase 3; D048369:MAP Kinase Kinase 1; C482125:MAP2K1 protein, human
keywords: ERK2; HGF; High-throughput screen; Motility; Paxillin; Signalling; Wound healing; c-Met; siRNA