title: OPG, RANK and RANK ligand expression in thyroid lesions.
abstract: Receptor activator of NF-kappaB (RANK), RANK ligand (RANKL) and osteoprotegerin (OPG) play essential roles in bone metabolism. RANKL binds to RANK, which is expressed by osteoclasts whereas OPG acts as its decoy receptor blocking the RANK-RANKL interaction. OPG/RANK/RANKL are produced by variety of tissues including epithelial and mesenchymal cells. However, the role of RANKL/OPG in thyroid pathophysiology remains unclear. The aim of this study was to determine the expression pattern of RANK/RANKL/OPG in primary neoplastic thyroid lesions and in lymph node metastases. 27 specimens from total thyroidectomy were studied by immunohistochemistry: 9 papillary carcinomas (PC), 9 medullary carcinomas (MC), 9 macrovesicular adenomas (MA). Immunohistochemical evidence of RANKL was found in 30 % of MC, 22% of PC while RANKL has never been detected in PC. The expression of RANK is closely related to RANKL. OPG was restricted to the cytoplasm of epithelial in 1 MA and 1 MC. In contrast to pathological tissues, any expression of OPG/RANK/RANKL was detected in healthy thyroid tissue. This work reveals for the first time that OPG/RANK/RANKL are expressed in the pathological thyroid gland by follicular cells, by malignant parafollicular cells as well as in metastatic lymph node microenvironment. Thus OPG/RANK/RANKL molecular triad might play a role during pathogenesis of follicular and parafollicular tumors.
authors: INSERM, ERI 7, Nantes, F-44035, France.
authors: Marie-Françoise
authors: MF
authors: Heymann
authors: Anne
authors: A
authors: Riet
authors: Benoît
authors: B
authors: Le Goff
authors: Séverine
authors: S
authors: Battaglia
authors: Jacques
authors: J
authors: Paineau
authors: Dominique
authors: D
authors: Heymann
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D018276:Carcinoma, Medullary / Q000378:metabolism / Q000473:pathology; D002291:Carcinoma, Papillary / Q000378:metabolism / Q000473:pathology; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008198:Lymph Nodes / Q000378:metabolism / Q000473:pathology; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D053244:Osteoprotegerin / Q000378:metabolism*; D053245:RANK Ligand / Q000378:metabolism*; D053246:Receptor Activator of Nuclear Factor-kappa B / Q000378:metabolism*; D013961:Thyroid Gland / Q000378:metabolism / Q000473:pathology; D013964:Thyroid Neoplasms / Q000378:metabolism* / Q000473:pathology
chemical_list: D053244:Osteoprotegerin; D053245:RANK Ligand; D053246:Receptor Activator of Nuclear Factor-kappa B