Osteoclast differentiation is associated with transient upregulation of cyclin-dependent kinase inhibitors p21(WAF1/CIP1) and p27(KIP1).
Osteoclasts, bone-resorbing multinucleated cells, develop from monocyte-macrophage lineage cells in the presence of osteoclast differentiation factor (ODF, also called RANKL/TRANCE/OPGL) and macrophage colony-stimulating factor (M-CSF). M-CSF-dependent bone marrow macrophages (M-BMMPhis) from mouse bone marrow cells have been shown to differentiate into osteoclast-like multinucleated cells (OCLs) in the presence of soluble ODF/RANKL (sODF/RANKL) and M-CSF within 3 days. In this study, we found that stimulation of M-BMMPhis with sODF/RANKL induced a transient expression of cyclin-dependent kinase inhibitors (CDK inhibitors) p21(WAF1/CIP1) and p27(KIP1) by 24 h. The CDK inhibitor proteins disappeared by 48 h. Tumor necrosis factor alpha (TNF-alpha), which is reported to stimulate OCL differentiation, stimulated p21(WAF1/CIP1) and p27(KIP1) expression in M-BMMPhis as well. However, M-CSF alone did not stimulate the expression of the two CDK inhibitors. To clarify the role of p21(WAF1/CIP1) and p27(KIP1) in osteoclastogenesis, accumulation of these CDK inhibitors was aborted by antisense oligonucleotides. Treatment with p21(WAF1/CIP1) antisense oligonucleotide alone, or p27(KIP1) antisense oligonucleotide alone, showed a limited inhibitory effect on OCL formation. However, treatment with a mixture of these two antisense oligonucleotides strongly inhibited OCL formation. These results suggest that a combined modulation of the CDK inhibitors p21(WAF1/CIP1) and p27(KIP1) may be involved in osteoclast differentiation induced by ODF/RANKL.
Okahashi
N
N
Department of Oral Science, National Institute of Infectious Diseases, Tokyo, Japan.
Murase
Y
Y
Koseki
T
T
Sato
T
T
Yamato
K
K
Nishihara
T
T
D000818:Animals; D001483:Base Sequence; D001854:Bone Marrow Cells / Q000166:cytology; D018797:Cell Cycle Proteins; D002454:Cell Differentiation / Q000187:drug effects; D002478:Cells, Cultured; D050759:Cyclin-Dependent Kinase Inhibitor p21; D050760:Cyclin-Dependent Kinase Inhibitor p27; D016213:Cyclins / Q000235:genetics / Q000378:metabolism*; D017931:DNA Primers; D004791:Enzyme Inhibitors / Q000378:metabolism*; D005260:Female; D008264:Macrophages / Q000166:cytology; D051379:Mice; D008869:Microtubule-Associated Proteins / Q000235:genetics / Q000378:metabolism*; D016376:Oligonucleotides, Antisense / Q000494:pharmacology; D010010:Osteoclasts / Q000166:cytology* / Q000187:drug effects; D025521:Tumor Suppressor Proteins; D015854:Up-Regulation
C493957:Cdkn1a protein, mouse; C493961:Cdkn1b protein, mouse; D018797:Cell Cycle Proteins; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins; D017931:DNA Primers; D004791:Enzyme Inhibitors; D008869:Microtubule-Associated Proteins; D016376:Oligonucleotides, Antisense; D025521:Tumor Suppressor Proteins; D050760:Cyclin-Dependent Kinase Inhibitor p27