title: Correlation of osteoprotegerin and sRANKL concentrations in serum and bone marrow of multiple myeloma patients.
abstract: BACKGROUND
  Recent studies suggest that multiple myeloma (MM) triggers osteoclastogenesis by disrupting the balance between the receptor activator of NF-kappaB ligand (RANKL) and osteoprotegerin (OPG), its natural antagonist.
  
  
  METHODS
  Determinations of bone marrow (BM) and serum OPG and sRANKL concentrations were performed in 133 MM patients and 42 healthy subjects by the ELISA method using Osteoprotegerin ELISA and sRANKL ELISA kits.
  
  
  RESULTS
  MM patients had elevated serum levels of OPG compared with controls (p<0.0001) and OPG levels were higher in patients with renal failure and patients with hipercalcemia (p<0.001 and p=0.04, respectively). Serum OPG levels correlated with age, serum beta 2-microglobulin, and BM OPG concentrations and did not correlate with the presence of osteolysis or with stage of disease. sRANKL serum levels in MM patients and in controls were not statistically different (p=0.42). In MM patients, serum OPG and sRANKL levels were similar at diagnosis and in the plateau phase of disease. There was a correlation between BM and serum sRANKL concentrations (p<0.001). Median values of the sRANKL/OPG ratio for BM and serum of MM patients were 0.14 and 0.11, respectively. The median value of the sRANKL/OPG ratio for the serum of controls was 0.11.
  
  
  CONCLUSIONS
  In 20% of MM patients, serum OPG levels are elevated, and this may be a compensative reaction related to increased bone destruction. There is not statistically significant relationship between sRANKL serum and BM levels and the main clinical and laboratory parameters of the disease. Determination of BM and the serum sRANKL/OPG ratio seems to have no clinical value.
authors.affiliation: Department of Hematology, Institute of Hematology and Blood Transfusion, Warsaw, Poland. mkraj@ihit.waw.pl
authors.forename: Maria
authors.initials: M
authors.lastname: Kraj
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Owczarska
authors.forename: Urszula
authors.initials: U
authors.lastname: Sokołowska
authors.forename: Piotr
authors.initials: P
authors.lastname: Centkowski
authors.forename: Ryszard
authors.initials: R
authors.lastname: Pogłód
authors.forename: Barbara
authors.initials: B
authors.lastname: Kruk
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001853:Bone Marrow / Q000737:chemistry*; D002352:Carrier Proteins / Q000032:analysis / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006023:Glycoproteins / Q000032:analysis / Q000097:blood*; D006801:Humans; D008297:Male; D008562:Membrane Glycoproteins / Q000032:analysis / Q000097:blood*; D008875:Middle Aged; D009101:Multiple Myeloma / Q000378:metabolism*; D053244:Osteoprotegerin; D053245:RANK Ligand; D053246:Receptor Activator of Nuclear Factor-kappa B; D018160:Receptors, Cytoplasmic and Nuclear / Q000032:analysis / Q000097:blood*; D018124:Receptors, Tumor Necrosis Factor / Q000032:analysis / Q000097:blood*
chemical_list: D002352:Carrier Proteins; D006023:Glycoproteins; D008562:Membrane Glycoproteins; D053244:Osteoprotegerin; D053245:RANK Ligand; D053246:Receptor Activator of Nuclear Factor-kappa B; D018160:Receptors, Cytoplasmic and Nuclear; D018124:Receptors, Tumor Necrosis Factor; C505686:TNFRSF11A protein, human; C506030:TNFRSF11B protein, human; C505688:TNFSF11 protein, human