title: Expression of osteoprotegerin and RANK ligand in breast cancer bone metastasis.
abstract: Bone destruction is primarily mediated by osteoclastic bone resorption, and cancer cells stimulate the formation and activation of osteoclasts next to metastatic foci. Accumulating evidences indicate that receptor activator of NF-kB ligand (RANKL) is the ultimate extracellular mediator that stimulates osteoclast differentiation into mature osteoclasts. In contrast, osteoprotegerin (OPG) inhibits osteoclast development. In order to elucidate a mechanism for cancer-induced osteoclastogenesis, cells from a human breast cancer line, MDA-MB-231, were directly co-cultured with ST2, MC3T3-E1, or with primary mouse calvarial cells. Osteoclast-like cells and tartarate resistant acid phosphatase (TRAP) activities were then quantitated. We examined these cell lines and samples from breast cancer by RT-PCR for the expressions of OPG and RANKL mRNA. Compared to controls, co-culture of MDA-MB-231 cells with stromal or osteoblastic cells induced an increase in number of osteoclasts and TRAP activities. MDA-MB-231 cells alone or breast cancer samples did not express RANKL mRNA. However, co-culture of these cancer cells with stromal or osteoblastic cells induced RANKL mRNA expression and decreased OPG mRNA expression. These experiments demonstrate that direct interactions between breast cancer and stromal or osteoblastic cells induce osteoclastogenesis in vitro through modulating RANKL expression.
authors.affiliation: Department of Pathology, College of Medicine, Hallym University, Chuncheon, Korea. hyerim@chol.com
authors.forename: Hye-Rim
authors.initials: HR
authors.lastname: Park
authors.forename: Soo-Kee
authors.initials: SK
authors.lastname: Min
authors.forename: Hyun-Deuk
authors.initials: HD
authors.lastname: Cho
authors.forename: Duck-Hwan
authors.initials: DH
authors.lastname: Kim
authors.forename: Hyung Sik
authors.initials: HS
authors.lastname: Shin
authors.forename: Young Euy
authors.initials: YE
authors.lastname: Park
mesh_terms: D016475:3T3 Cells; D000135:Acid Phosphatase / Q000378:metabolism; D000818:Animals; D001859:Bone Neoplasms / Q000378:metabolism* / Q000556:secondary*; D001943:Breast Neoplasms / Q000473:pathology*; D002352:Carrier Proteins / Q000096:biosynthesis*; D002454:Cell Differentiation; D045744:Cell Line, Tumor; D002478:Cells, Cultured; D018920:Coculture Techniques; D017077:Culture Media, Conditioned / Q000494:pharmacology; D006023:Glycoproteins / Q000096:biosynthesis*; D006801:Humans; D007527:Isoenzymes / Q000378:metabolism; D008297:Male; D008562:Membrane Glycoproteins / Q000096:biosynthesis*; D051379:Mice; D008810:Mice, Inbred C57BL; D009362:Neoplasm Metastasis; D010006:Osteoblasts / Q000378:metabolism; D010010:Osteoclasts / Q000378:metabolism; D053244:Osteoprotegerin; D011485:Protein Binding; D053245:RANK Ligand; D012333:RNA, Messenger / Q000378:metabolism; D053246:Receptor Activator of Nuclear Factor-kappa B; D018160:Receptors, Cytoplasmic and Nuclear / Q000096:biosynthesis*; D018124:Receptors, Tumor Necrosis Factor; D020133:Reverse Transcriptase Polymerase Chain Reaction; D000071681:Tartrate-Resistant Acid Phosphatase; D013997:Time Factors
chemical_list: D002352:Carrier Proteins; D017077:Culture Media, Conditioned; D006023:Glycoproteins; D007527:Isoenzymes; D008562:Membrane Glycoproteins; D053244:Osteoprotegerin; D053245:RANK Ligand; D012333:RNA, Messenger; D053246:Receptor Activator of Nuclear Factor-kappa B; D018160:Receptors, Cytoplasmic and Nuclear; D018124:Receptors, Tumor Necrosis Factor; C505686:TNFRSF11A protein, human; C506030:TNFRSF11B protein, human; C505688:TNFSF11 protein, human; C505687:Tnfrsf11a protein, mouse; C506031:Tnfrsf11b protein, mouse; C505689:Tnfsf11 protein, mouse; D000135:Acid Phosphatase; C000605511:Acp5 protein, mouse; D000071681:Tartrate-Resistant Acid Phosphatase