title: The molecular triad OPG/RANK/RANKL: involvement in the orchestration of pathophysiological bone remodeling.
abstract: The past decade has seen an explosion in the field of bone biology. The area of bone biology over this period of time has been marked by a number of key discoveries that have opened up entirely new areas for investigation. The recent identification of the receptor activator of nuclear factor kappaB ligand (RANKL), its cognate receptor RANK, and its decoy receptor osteoprotegerin (OPG) has led to a new molecular perspective on osteoclast biology and bone homeostasis. Specifically, the interaction between RANKL and RANK has been shown to be required for osteoclast differentiation. The third protagonist, OPG, acts as a soluble receptor antagonist for RANKL that prevents it from binding to and activating RANK. Any dysregulation of their respective expression leads to pathological conditions such as bone tumor-associated osteolysis, immune disease, or cardiovascular pathology. In this context, the OPG/RANK/RANKL triad opens novel therapeutic areas in diseases characterized by excessive bone resorption. The present article is an update and extension of an earlier review published by Kwan Tat et al. [Kwan Tat S, Padrines M, Theoleyre S, Heymann D, Fortun Y. IL-6, RANKL, TNF-alpha/IL-1: interrelations in bone resorption pathophysiology. Cytokine Growth Factor Rev 2004;15:49-60].
authors.affiliation: EA 3822, INSERM ESPRI, Physiopathologie de la Résorption Osseuse et Thérapie des Tumeurs Osseuses Primitives, Faculté de Médecine, 1 rue Gaston Veil, 44035 Nantes Cedex 1, France.
authors.forename: Sandrine
authors.initials: S
authors.lastname: Theoleyre
authors.forename: Yohann
authors.initials: Y
authors.lastname: Wittrant
authors.forename: Steeve Kwan
authors.initials: SK
authors.lastname: Tat
authors.forename: Yannick
authors.initials: Y
authors.lastname: Fortun
authors.forename: Francoise
authors.initials: F
authors.lastname: Redini
authors.forename: Dominique
authors.initials: D
authors.lastname: Heymann
mesh_terms: D000818:Animals; D001808:Blood Vessels / Q000033:anatomy & histology / Q000502:physiology; D001847:Bone Diseases / Q000473:pathology / Q000503:physiopathology / Q000628:therapy; D016723:Bone Remodeling / Q000502:physiology*; D001842:Bone and Bones / Q000473:pathology / Q000502:physiology; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D002454:Cell Differentiation; D006023:Glycoproteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007107:Immune System / Q000502:physiology; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism*; D010010:Osteoclasts / Q000502:physiology; D053244:Osteoprotegerin; D053245:RANK Ligand; D053246:Receptor Activator of Nuclear Factor-kappa B; D018160:Receptors, Cytoplasmic and Nuclear / Q000235:genetics / Q000378:metabolism*; D018124:Receptors, Tumor Necrosis Factor; D048029:TNF Receptor-Associated Factor 6 / Q000378:metabolism
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; D048029:TNF Receptor-Associated Factor 6; C505686:TNFRSF11A protein, human; C506030:TNFRSF11B protein, human; C505688:TNFSF11 protein, human