title: Markers of bone metastases in breast and lung cancers.
abstract: OBJECTIVE
  The aim of the present study was to evaluate correlations between serum osteocalcin, osteoprotegerin and NTX (Cross-linked N-telopeptides of Type I Collagen) and urinary NTX in breast and lung cancer patients with bone metastases. These four markers are considered to have important roles in bone formation, resorption and metastases.
  
  
  METHODS
  Four markers were determined in the sera of 60 breast cancer and 21 lung cancer patients and healthy controls (n=30). Serum levels were studied using ELISA and EIA.
  
  
  RESULTS
  The median levels of serum osteoprotegerin (p<0.001) and osteocalcin (p=0.003) were higher in patients. Significant correlations were observed between the serum NTX-osteocalcin (r=0.431; p<0.001), serum NTX- osteoprotegerin (r=0.42; p=0.003) and serum NTX - urine NTX (r=0.255; p=0.022).
  
  
  CONCLUSIONS
  We conclude that osteocalcin, osteoprotegerin and NTX are independent diagnostic tools. Due to the ease of urine collection, urine NTX may be applied routinely to allow early detection of bone metastases and indicate progression of the disease.
authors.affiliation: Basic Oncology, Istanbul University Oncology Institute, Istanbul-Turkey.
authors.forename: Elif
authors.initials: E
authors.lastname: Bilgin
authors.forename: Vildan
authors.initials: V
authors.lastname: Yasasever
authors.forename: Hilal Oguz
authors.initials: HO
authors.lastname: Soydinc
authors.forename: Ceren Tilgen
authors.initials: CT
authors.lastname: Yasasever
authors.forename: Nakiye
authors.initials: N
authors.lastname: Ozturk
authors.forename: Derya
authors.initials: D
authors.lastname: Duranyildiz
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood* / Q000652:urine*; D001859:Bone Neoplasms / Q000097:blood / Q000556:secondary* / Q000652:urine; D001943:Breast Neoplasms / Q000473:pathology*; D016022:Case-Control Studies; D024042:Collagen Type I / Q000097:blood / Q000652:urine; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D015675:Osteocalcin / Q000097:blood; D053244:Osteoprotegerin / Q000097:blood; D010455:Peptides / Q000097:blood / Q000652:urine
chemical_list: D014408:Biomarkers, Tumor; D024042:Collagen Type I; D053244:Osteoprotegerin; D010455:Peptides; C052929:collagen type I trimeric cross-linked peptide; D015675:Osteocalcin