title: Osteoprotegerin in breast cancer: beyond bone remodeling.
abstract: Osteoprotegerin (OPG) is a secreted protein and member of the Tumor Necrosis Factor (TNF) Receptor superfamily. OPG has been well characterized as a regulator of bone metabolism which acts by blocking osteoclast maturation and preventing bone breakdown. Given this role, early studies on OPG in breast cancer focused on the administration of OPG in order to prevent the osteolysis observed with bone metastases. However OPG is also produced by the breast tumor cells themselves. Research focusing on OPG produced by breast tumor cells has revealed actions of OPG which promote tumor progression. In vitro studies into the role of OPG produced by breast tumor cells have demonstrated that OPG can block TNF-related apoptosis inducing ligand (TRAIL)-mediated apoptosis. Furthermore, in vivo studies show that OPG expression by breast tumors can promote tumor growth and metastasis. In addition it has been shown that OPG stimulates endothelial cell survival and tube formation thus it may indirectly promote breast tumor progression through impacting angiogenesis. This article will present a summary of the data concerning the tumor-promoting effects of OPG in breast cancer.
authors.affiliation: Division of Natural Science and Mathematics, Chaminade University of Honolulu, 3140 Waialae Avenue, Honolulu, HI, 96816, USA. michael.weichhaus@chaminade.edu.
authors.forename: Michael
authors.initials: M
authors.lastname: Weichhaus
authors.affiliation: Department of Pharmaceutical Sciences, Daniel K. Inouye College of Pharmacy, University of Hawaii at Hilo, Hilo, HI, 96720, USA. stmc@hawaii.edu.
authors.forename: Stephanie Tsang Mui
authors.initials: ST
authors.lastname: Chung
authors.affiliation: Department of Pharmaceutical Sciences, Daniel K. Inouye College of Pharmacy, University of Hawaii at Hilo, Hilo, HI, 96720, USA. lindacon@hawaii.edu.
authors.forename: Linda
authors.initials: L
authors.lastname: Connelly
mesh_terms: D000818:Animals; D001859:Bone Neoplasms / Q000556:secondary; D016723:Bone Remodeling; D001943:Breast Neoplasms / Q000378:metabolism*; D042783:Endothelial Cells / Q000378:metabolism; D005260:Female; D006801:Humans; D053244:Osteoprotegerin / Q000235:genetics / Q000378:metabolism*; D053221:TNF-Related Apoptosis-Inducing Ligand / Q000378:metabolism
chemical_list: D053244:Osteoprotegerin; D053221:TNF-Related Apoptosis-Inducing Ligand