title: Immunohistochemical study of receptor activator of nuclear factor kappa-B ligand (RANK-L) in human osteolytic bone tumors.
abstract: OBJECTIVE
  Osteolytic bone tumors produce intercellular signaling proteins that regulate bone remodeling by altering the rates of osteoclast and osteoblast differentiation and activity. This report examines osteolytic bone tumor expression of receptor activator of nuclear factor B-ligand (RANK-L), a cytokine that is arguably the most critical regulator of osteoclast differentiation and activation.
  
  
  METHODS
  This prospective immunohistochemical study examined RANK-L expression in frozen tissues from sixteen surgical specimens of patients who underwent surgery for the treatment of osteolytic bone tumors between 1999 and 2000.
  
  
  RESULTS
  RANK-L was positive in 13 of the 16 cases. Primary benign bone tumors, primary malignant bone tumors, and metastasis to bone were positive for RANK-L.
  
  
  CONCLUSIONS
  The cells in some, but not all, osteolytic tumors produce the cytokine RANK-L. Further study is necessary to determine in which specific tumors RANK-L is the cytokine responsible for increased osteoclastic activity, and to develop possible therapeutic use of RANK-L antagonists such as osteoprotegerin (OPG).
authors.affiliation: Department of Orthopaedics, University of Rochester School of Medicine, Rochester, New York 14642, USA.
authors.forename: Christopher R
authors.initials: CR
authors.lastname: Good
authors.forename: Regis J
authors.initials: RJ
authors.lastname: O'Keefe
authors.forename: J Edward
authors.initials: JE
authors.lastname: Puzas
authors.forename: Edward M
authors.initials: EM
authors.lastname: Schwarz
authors.forename: Randy N
authors.initials: RN
authors.lastname: Rosier
mesh_terms: D001859:Bone Neoplasms / Q000378:metabolism* / Q000473:pathology; D002352:Carrier Proteins / Q000096:biosynthesis* / Q000502:physiology; D002454:Cell Differentiation; D002467:Cell Nucleus / Q000378:metabolism; D018214:Fibroma, Ossifying / Q000378:metabolism; D018219:Histiocytoma, Benign Fibrous / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D008562:Membrane Glycoproteins / Q000096:biosynthesis* / Q000502:physiology; D010006:Osteoblasts / Q000166:cytology; D010010:Osteoclasts / Q000166:cytology; D010014:Osteolysis; D011446:Prospective Studies; D053245:RANK Ligand; D053246:Receptor Activator of Nuclear Factor-kappa B
chemical_list: D002352:Carrier Proteins; D008562:Membrane Glycoproteins; D053245:RANK Ligand; D053246:Receptor Activator of Nuclear Factor-kappa B; C505686:TNFRSF11A protein, human; C505688:TNFSF11 protein, human