title: In vitro and in vivo effects of suppressor of cytokine signalling 7 knockdown in breast cancer: the influence on cellular response to hepatocyte growth factor.
abstract: OBJECTIVE
  Suppressor of cytokine signaling 7 (SOCS7) is a member of the SOCS family and is known to interact with phospholipase Cγ-1 (PLCγ-1), a key downstream mediator of the hepatocyte growth factor (HGF)/C-MET axis. Here, we report our observations of the effect of knocking down SOCS7 gene on the behaviour of breast cancer cells both in vitro and in vivo and to elucidate whether this involves HGF/C-MET pathway using the PLCγ-1 blocker U73122.
  
  
  METHODS
  MCF7 and MDA-MB-231 breast cancer cells were transfected with anti-SOCS7 ribozymal transgene, to create sublines with SOCS7 knockdown. The in vitro growth and migration of the cells were evaluated in basic conditions and with HGF and U73122 treatment using growth assays, scratch-wound, and electrical cell impedance sensing (ECIS) migration assays. MCF7 and MDA-MB-231 in vivo tumour xenograft growth were also studied.
  
  
  RESULTS
  Basal in vitro growth and migration of both cellular lines and the in vivo MCF7 xenograft growth were significantly enhanced with SOCS7 knockdown. In vitro HGF treatment has further influenced the growth and migration when SOCS7 gene was knocked-down in both cellular lines (P < 0.05). PLCγ-1 pharmacological inhibition of the HGF/C-MET cascade during their in vitro growth and migration seemed to only occur when SOCS7 gene was knocked down.
  
  
  CONCLUSIONS
  We report a unique regulatory role for SOCS7 in controlling the malignant behaviour of breast cancer lines MCF7 and MDA-MB-231 in vitro and the MCF7 tumour xenografts in vivo. We also report a regulatory role for SOCS7 during the in vitro HGF-induced growth and migration in these cells as HGF treatment and SOCS7 loss have synergistically enhanced these functions. This SOCS7 knockdown-attributed effect could be due to a precise anti-PLCγ-1 role.
authors.affiliation: St. George's University of London, London SW17 0RE, UK.
authors.forename: Walid
authors.identifier: 0000-0002-6924-8528
authors.initials: W
authors.lastname: Sasi
authors.affiliation: Cardiff University, Cardiff CF10 3XQ, UK.
authors.forename: Lin
authors.initials: L
authors.lastname: Ye
authors.affiliation: Cardiff University, Cardiff CF10 3XQ, UK.
authors.forename: Wen G
authors.initials: WG
authors.lastname: Jiang
authors.affiliation: St. George's University of London, London SW17 0RE, UK.
authors.forename: Anup K
authors.initials: AK
authors.lastname: Sharma
authors.affiliation: St. George's University of London, London SW17 0RE, UK ; The London Breast Institute, The Princess Grace Hospital, London W1U 5NY, UK.
authors.forename: Kefah
authors.initials: K
authors.lastname: Mokbel
mesh_terms: D000818:Animals; D001943:Breast Neoplasms / Q000188:drug therapy / Q000235:genetics* / Q000473:pathology; D004963:Estrenes / Q000008:administration & dosage; D005260:Female; D055785:Gene Knockdown Techniques; D017228:Hepatocyte Growth Factor / Q000235:genetics / Q000378:metabolism; D006801:Humans; D061986:MCF-7 Cells; D051379:Mice; D009687:Nuclear Proteins / Q000235:genetics*; D051966:Phospholipase C gamma / Q000037:antagonists & inhibitors; D019859:Proto-Oncogene Proteins c-met / Q000378:metabolism; D011760:Pyrrolidinones / Q000008:administration & dosage; D015398:Signal Transduction / Q000187:drug effects; D050826:Suppressor of Cytokine Signaling Proteins / Q000235:genetics*; D023041:Xenograft Model Antitumor Assays
chemical_list: D004963:Estrenes; D009687:Nuclear Proteins; D011760:Pyrrolidinones; C108775:SOCS7 protein, human; D050826:Suppressor of Cytokine Signaling Proteins; C060229:1-(6-((3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione; D017228:Hepatocyte Growth Factor; D019859:Proto-Oncogene Proteins c-met; D051966:Phospholipase C gamma