Serum osteoprotegerin levels in healthy controls and cancer patients.
OBJECTIVE
Osteoprotegerin (OPG) is a novel secreted member of the tumor necrosis factor receptor superfamily. In vitro, OPG blocks osteoclastogenesis in a dose-dependent manner. Serum OPG levels were assayed in cancer patients and healthy control subjects using an ELISA.


RESULTS
OPG levels in healthy controls were significantly higher in sera (0.17 ng/ml) than in plasma (0.14 ng/ml). OPG levels did not differ by age in either control group. Serum was available from patients with solid tumors (n = 145), hematological malignancies (n = 111), benign hematological disorders (n = 35), and rheumatologic diseases (n = 60). When adjusted for age and sex, there was no significant OPG elevation in the sera of patients with solid tumors compared with controls (0.2 versus 0.18 ng/ml). When analyzed by site of primary malignancy within the solid tumor patient group, serum OPG elevations were observed only in patients with colorectal cancer (0.29 ng/ml; P < 0.0001) and pancreatic cancer (0.35 ng/ml; P < 0.0001). When analyzed by site of metastasis within the solid tumor patient group, significant elevations in serum OPG were observed only in patients with liver metastases (0.29 ng/ml) and soft tissue metastases (0.21 ng/ml) but not in patients with bone or lung metastases. Within the hematological malignancy group, serum levels of OPG were significantly lower in patients with multiple myeloma (0.12 ng/ml) but were elevated in patients with Hodgkin's disease (0.29 ng/ml) and Non-Hodgkin's Lymphoma (0.24 ng/ml; P = 0.048).


CONCLUSIONS
Although some patients with malignancy have significant elevations of circulating OPG, these concentrations do not approach the level that would be expected to suppress osteoclast function.
Lipton
Allan
A
Division of Hematology, Milton S. Hershey Medical Center, Hershey, PA 17033, USA. alipton@psu.edu
Ali
Suhail M
SM
Leitzel
Kim
K
Chinchilli
Vernon
V
Witters
Lois
L
Engle
Linda
L
Holloway
Donna
D
Bekker
Pirow
P
Dunstan
Colin R
CR
D000293:Adolescent; D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006023:Glycoproteins / Q000097:blood*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000097:blood* / Q000473:pathology; D053244:Osteoprotegerin; D018160:Receptors, Cytoplasmic and Nuclear / Q000097:blood*; D018124:Receptors, Tumor Necrosis Factor / Q000097:blood*; D012216:Rheumatic Diseases / Q000097:blood / Q000473:pathology
D006023:Glycoproteins; D053244:Osteoprotegerin; D018160:Receptors, Cytoplasmic and Nuclear; D018124:Receptors, Tumor Necrosis Factor; C506030:TNFRSF11B protein, human