title: Expression of the Components of the Renin-Angiotensin System in Venous Malformation.
abstract: BACKGROUND
  Venous malformation (VM) is the most common form of vascular malformation, consisting of a network of thin-walled ectatic venous channels with deficient or absent media. This study investigated the expression of the components of the renin-angiotensin system (RAS), namely, (pro)renin receptor (PRR), angiotensin-converting enzyme (ACE), angiotensin II receptor 1 (ATIIR1), and angiotensin II receptor 2 (AIITR2) in subcutaneous (SC) and intramuscular (IM) VM.
  
  
  METHODS
  SC (n = 7) and IM (n = 7) VM were analyzed for the expression of PRR, ACE, ATIIR1, and ATIIR2 using 3,3-diaminobenzidine and immunofluorescent (IF) immunohistochemical (IHC) staining and NanoString gene expression analysis.
  
  
  RESULTS
  IHC staining showed expression of PRR, ACE, and ATIIR1, and faint expression of ATIIR2 in the endothelium of SC and IM VM. Furthermore, ATIIR2 was expressed by cells away from the endothelium in both SC and IM VM lesions examined. NanoString analysis demonstrated the presence of PRR, ACE, and ATIIR1 but not ATIIR2.
  
  
  CONCLUSIONS
  The presence of PRR, ACE, ATIIR1, and potentially ATIIR2, in both SC and IM VM, suggests a role for the RAS in the biology of VM. This novel finding may lead to a mechanism-based therapy for VM.
authors.affiliation: Gillies McIndoe Research Institute , Wellington , New Zealand.
authors.forename: Sam
authors.initials: S
authors.lastname: Siljee
authors.affiliation: Gillies McIndoe Research Institute , Wellington , New Zealand.
authors.forename: Emily
authors.initials: E
authors.lastname: Keane
authors.affiliation: Gillies McIndoe Research Institute, Wellington, New Zealand; University of Auckland, Auckland, New Zealand.
authors.forename: Reginald
authors.initials: R
authors.lastname: Marsh
authors.affiliation: Gillies McIndoe Research Institute, Wellington, New Zealand; Department of Pathology, Hutt Hospital, Wellington, New Zealand.
authors.forename: Helen D
authors.initials: HD
authors.lastname: Brasch
authors.affiliation: Gillies McIndoe Research Institute, Wellington, New Zealand; Centre for the Study and Treatment of Vascular Birthmarks, Wellington Regional Plastic, Maxillofacial and Burns Unit, Hutt Hospital, Wellington, New Zealand.
authors.forename: Swee T
authors.initials: ST
authors.lastname: Tan
authors.affiliation: Gillies McIndoe Research Institute , Wellington , New Zealand.
authors.forename: Tinte
authors.initials: T
authors.lastname: Itinteang
keywords: angiotensin; malformation; pro-renin; receptors; renin; system; venous