title: Targeting Cx43 and N-cadherin, which are abnormally upregulated in venous leg ulcers, influences migration, adhesion and activation of Rho GTPases.
abstract: BACKGROUND
  Venous leg ulcers can be very hard to heal and represent a significant medical need with no effective therapeutic treatment currently available.
  
  
  RESULTS
  In wound edge biopsies from human venous leg ulcers we found a striking upregulation of dermal N-cadherin, Zonula Occludens-1 and the gap junction protein Connexin43 (Cx43) compared to intact skin, and in stark contrast to the down-regulation of Cx43 expression seen in acute, healing wounds. We targeted the expression of these proteins in 3T3 fibroblasts to evaluate their role in venous leg ulcers healing. Knockdown of Cx43 and N-cadherin, but not Zonula Occludens-1, accelerated cell migration in a scratch wound-healing assay. Reducing Cx43 increased Golgi reorientation, whilst decreasing cell adhesion and proliferation. Furthermore, Connexin43 and N-cadherin knockdown led to profound effects on fibroblast cytoskeletal dynamics after scratch-wounding. The cells exhibited longer lamelipodial protrusions lacking the F-actin belt seen at the leading edge in wounded control cells. This phenotype was accompanied by augmented activation of Rac-1 and RhoA GTPases, as revealed by Förster Resonance Energy Transfer and pull down experiments.
  
  
  CONCLUSIONS
  Cx43 and N-cadherin are potential therapeutic targets in the promotion of healing of venous leg ulcers, by acting at least in part through distinct contributions of cell adhesion, migration, proliferation and cytoskeletal dynamics.
authors.affiliation: Department of Cell and Developmental Biology, University College London, London, United Kingdom. a.mendoza@ucl.ac.uk
authors.forename: Ariadna
authors.initials: A
authors.lastname: Mendoza-Naranjo
authors.forename: Peter
authors.initials: P
authors.lastname: Cormie
authors.forename: Antonio E
authors.initials: AE
authors.lastname: Serrano
authors.forename: Rebecca
authors.initials: R
authors.lastname: Hu
authors.forename: Shay
authors.initials: S
authors.lastname: O'Neill
authors.forename: Chiuhui Mary
authors.initials: CM
authors.lastname: Wang
authors.forename: Christopher
authors.initials: C
authors.lastname: Thrasivoulou
authors.forename: Kieran T
authors.initials: KT
authors.lastname: Power
authors.forename: Alexis
authors.initials: A
authors.lastname: White
authors.forename: Thomas
authors.initials: T
authors.lastname: Serena
authors.forename: Anthony R J
authors.initials: AR
authors.lastname: Phillips
authors.forename: David L
authors.initials: DL
authors.lastname: Becker
mesh_terms: D016475:3T3 Cells; D000818:Animals; D015820:Cadherins / Q000502:physiology*; D002448:Cell Adhesion / Q000235:genetics; D002465:Cell Movement / Q000235:genetics; D049109:Cell Proliferation / Q000187:drug effects; D018031:Connexin 43 / Q000502:physiology*; D031541:Fluorescence Resonance Energy Transfer; D006801:Humans; D007866:Leg; D008565:Membrane Proteins / Q000235:genetics; D051379:Mice; D010750:Phosphoproteins / Q000235:genetics; D015854:Up-Regulation; D014647:Varicose Ulcer / Q000235:genetics / Q000503:physiopathology*; D014945:Wound Healing / Q000502:physiology; D062826:Zonula Occludens-1 Protein; D020741:rho GTP-Binding Proteins / Q000378:metabolism
chemical_list: D015820:Cadherins; D018031:Connexin 43; D008565:Membrane Proteins; D010750:Phosphoproteins; C569042:TJP1 protein, human; C569043:Tjp1 protein, mouse; D062826:Zonula Occludens-1 Protein; D020741:rho GTP-Binding Proteins