title: Elevated serum angiotensin converting enzyme levels as a reflection of bone marrow renin-angiotensin system activation in multiple myeloma.
abstract: BACKGROUND
  Angiotensin converting enzyme (ACE) is a circulating enzyme that participates in the body's renin-angiotensin system (RAS) and is localized on the endothelial cell surface in the lung and other vascular beds. It catalyses the conversion of decapeptide angiotensin I to octapeptide angiotensin II. In the present study, we aimed to analyse the possible relationship between the levels of ACE in the context of RAS in multiple myeloma (MM) pathogenesis.
  
  
  METHODS
  The study was conducted on 25 MM patients (13 males, 12 females; median age 66 years, range 47-88) and 20 healthy controls. The clinical features of MM patients including demographics and laboratory findings were summarized. Serum ACE levels were measured by using commercially available kits.
  
  
  RESULTS
  The serum ACE levels of MM patients and controls were 32.60±20.26 and 15.35±6.47 respectively. Serum ACE levels were significantly higher in MM patients compared with control groups (p<0.001).
  
  
  CONCLUSIONS
  Being an important component of RAS, circulating ACE might be associated with clonal proliferation of malignant plasma cells in the bone marrow microenvironment. Identification of the pathobiological activity of the local RAS in MM would enlighten the biologic basis and clinical management of haematologic disorders.
authors.affiliation: Diskapi Education and Research Hospital, Department of Haematology, Ankara, Turkey.
authors.forename: Murat
authors.initials: M
authors.lastname: Albayrak
authors.forename: Harika
authors.initials: H
authors.lastname: Celebi
authors.forename: Aynur
authors.initials: A
authors.lastname: Albayrak
authors.forename: Abdurrahim
authors.initials: A
authors.lastname: Sayilir
authors.forename: Yusuf
authors.initials: Y
authors.lastname: Yesil
authors.forename: Ozlem Sahin
authors.initials: OS
authors.lastname: Balcik
authors.forename: Osman
authors.initials: O
authors.lastname: Yokus
authors.forename: Tugrul
authors.initials: T
authors.lastname: Celik
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001707:Biopsy, Needle; D001772:Blood Cell Count; D001853:Bone Marrow / Q000378:metabolism* / Q000473:pathology; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009101:Multiple Myeloma / Q000097:blood* / Q000201:enzymology* / Q000473:pathology; D007703:Peptidyl-Dipeptidase A / Q000097:blood*; D012084:Renin-Angiotensin System
chemical_list: C488034:ACE protein, human; D007703:Peptidyl-Dipeptidase A