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Karanth DS, Martin ML, Holliday LS. Plasma Membrane Receptors Involved in the Binding and Response of Osteoclasts to Noncellular Components of the Bone. Int J Mol Sci 2021; 22:ijms221810097. [PMID: 34576260 PMCID: PMC8466431 DOI: 10.3390/ijms221810097] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 09/13/2021] [Accepted: 09/16/2021] [Indexed: 12/21/2022] Open
Abstract
Osteoclasts differentiate from hematopoietic cells and resorb the bone in response to various signals, some of which are received directly from noncellular elements of the bone. In vitro, adherence to the bone triggers the reduction of cell–cell fusion events between osteoclasts and the activation of osteoclasts to form unusual dynamic cytoskeletal and membrane structures that are required for degrading the bone. Integrins on the surface of osteoclasts are known to receive regulatory signals from the bone matrix. Regulation of the availability of these signals is accomplished by enzymatic alterations of the bone matrix by protease activity and phosphorylation/dephosphorylation events. Other membrane receptors are present in osteoclasts and may interact with as yet unidentified signals in the bone. Bone mineral has been shown to have regulatory effects on osteoclasts, and osteoclast activity is also directly modulated by mechanical stress. As understanding of how osteoclasts and other bone cells interact with the bone has emerged, increasingly sophisticated efforts have been made to create bone biomimetics that reproduce both the structural properties of the bone and the bone’s ability to regulate osteoclasts and other bone cells. A more complete understanding of the interactions between osteoclasts and the bone may lead to new strategies for the treatment of bone diseases and the production of bone biomimetics to repair defects.
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Affiliation(s)
- Divakar S. Karanth
- Department of Orthodontics, College of Dentistry, University of Florida, Gainesville, FL 32610, USA; (D.S.K.); (M.L.M.)
| | - Macey L. Martin
- Department of Orthodontics, College of Dentistry, University of Florida, Gainesville, FL 32610, USA; (D.S.K.); (M.L.M.)
| | - Lexie S. Holliday
- Department of Orthodontics, College of Dentistry, University of Florida, Gainesville, FL 32610, USA; (D.S.K.); (M.L.M.)
- Department of Anatomy & Cell Biology, College of Medicine, University of Florida, Gainesville, FL 32610, USA
- Correspondence:
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Cohen K, Ellis M, Shinderman E, Khoury S, Davis PJ, Hercbergs A, Ashur-Fabian O. Relevance of the thyroid hormones-αvβ3 pathway in primary myeloma bone marrow cells and to bortezomib action. Leuk Lymphoma 2014; 56:1107-14. [PMID: 25058375 DOI: 10.3109/10428194.2014.947612] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Thyroid hormones (T3 and T4) induce proliferation in multiple myeloma (MM) cell lines via the αvβ3 integrin-mitogen-activated protein kinase (MAPK) pathway. We further show in primary MM bone marrow (BM) samples (n = 9) induction of cell viability by 1 nM T3 (13%, p < 0.002) and more potently by 100 nM T4 (21-45%, p < 0.0002) and a quick (1 h) and long-lasting (24 h) pERK activation, which was inhibited in the presence of β3 but not β1 blocking antibodies. Involvement of the integrin was further shown by two disintegrins, Arg-Gly-Asp (RGD) and echistatin peptides, which occluded the effects of T3/T4 on viability, proliferating cell nuclear antigen (PCNA) (proliferation marker) and apoptotic gene expression. Lastly, T3/T4 significantly opposed bortezomib (25 nM) cytotoxicy, as confirmed by several methods. In summary, our results imply that endogenous thyroid hormones in myeloma are factors that may support cell growth, with relevance to bortezomib action.
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Affiliation(s)
- Keren Cohen
- Translational Hemato-Oncology Laboratory, The Hematology Institute and Blood Bank, Meir Medical Center , Kfar-Saba , Israel
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Mochizuki A, Takami M, Miyamoto Y, Nakamaki T, Tomoyasu S, Kadono Y, Tanaka S, Inoue T, Kamijo R. Cell adhesion signaling regulates RANK expression in osteoclast precursors. PLoS One 2012; 7:e48795. [PMID: 23139818 PMCID: PMC3490906 DOI: 10.1371/journal.pone.0048795] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Accepted: 10/01/2012] [Indexed: 11/30/2022] Open
Abstract
Cells with monocyte/macrophage lineage expressing receptor activator of NF-κB (RANK) differentiate into osteoclasts following stimulation with the RANK ligand (RANKL). Cell adhesion signaling is also required for osteoclast differentiation from precursors. However, details of the mechanism by which cell adhesion signals induce osteoclast differentiation have not been fully elucidated. To investigate the participation of cell adhesion signaling in osteoclast differentiation, mouse bone marrow-derived macrophages (BMMs) were used as osteoclast precursors, and cultured on either plastic cell culture dishes (adherent condition) or the top surface of semisolid methylcellulose gel loaded in culture tubes (non-adherent condition). BMMs cultured under the adherent condition differentiated into osteoclasts in response to RANKL stimulation. However, under the non-adherent condition, the efficiency of osteoclast differentiation was markedly reduced even in the presence of RANKL. These BMMs retained macrophage characteristics including phagocytic function and gene expression profile. Lipopolysaccharide (LPS) and tumor necrosis factor –αTNF-α activated the NF-κB-mediated signaling pathways under both the adherent and non-adherent conditions, while RANKL activated the pathways only under the adherent condition. BMMs highly expressed RANK mRNA and protein under the adherent condition as compared to the non-adherent condition. Also, BMMs transferred from the adherent to non-adherent condition showed downregulated RANK expression within 24 hours. In contrast, transferring those from the non-adherent to adherent condition significantly increased the level of RANK expression. Moreover, interruption of cell adhesion signaling by echistatin, an RGD-containing disintegrin, decreased RANK expression in BMMs, while forced expression of either RANK or TNFR-associated factor 6 (TRAF6) in BMMs induced their differentiation into osteoclasts even under the non-adherent condition. These results suggest that cell adhesion signaling regulates RANK expression in osteoclast precursors.
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Affiliation(s)
- Ayako Mochizuki
- Department of Biochemistry, School of Dentistry, Showa University, Shinagawa, Tokyo, Japan
- Department of Oral Physiology, School of Dentistry, Showa University, Shinagawa, Tokyo, Japan
| | - Masamichi Takami
- Department of Biochemistry, School of Dentistry, Showa University, Shinagawa, Tokyo, Japan
- * E-mail:
| | - Yoichi Miyamoto
- Department of Biochemistry, School of Dentistry, Showa University, Shinagawa, Tokyo, Japan
| | - Tsuyoshi Nakamaki
- Division of Hematology, Department of Medicine, Showa University School of Medicine, Shinagawa, Tokyo, Japan
| | - Shigeru Tomoyasu
- Division of Hematology, Department of Medicine, Showa University School of Medicine, Shinagawa, Tokyo, Japan
| | - Yuho Kadono
- Department of Orthopaedic Surgery, Faculty of Medicine, The University of Tokyo, Bunkyo, Tokyo, Japan
| | - Sakae Tanaka
- Department of Orthopaedic Surgery, Faculty of Medicine, The University of Tokyo, Bunkyo, Tokyo, Japan
| | - Tomio Inoue
- Department of Oral Physiology, School of Dentistry, Showa University, Shinagawa, Tokyo, Japan
| | - Ryutaro Kamijo
- Department of Biochemistry, School of Dentistry, Showa University, Shinagawa, Tokyo, Japan
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ROSENTHAL MA, DAVIDSON P, ROLLAND F, CAMPONE M, XUE L, HAN TH, MEHTA A, BERD Y, HE W, LOMBARDI A. Evaluation of the safety, pharmacokinetics and treatment effects of an ανβ3integrin inhibitor on bone turnover and disease activity in men with hormone-refractory prostate cancer and bone metastases. Asia Pac J Clin Oncol 2010; 6:42-8. [DOI: 10.1111/j.1743-7563.2009.01266.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Heckmann D, Laufer B, Marinelli L, Limongelli V, Novellino E, Zahn G, Stragies R, Kessler H. Breaking the dogma of the metal-coordinating carboxylate group in integrin ligands: introducing hydroxamic acids to the MIDAS to tune potency and selectivity. Angew Chem Int Ed Engl 2009; 48:4436-40. [PMID: 19343753 DOI: 10.1002/anie.200900206] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
A suitable substitute: All integrin receptors bind their ligands, which contain an aspartate residue, in the metal-ion- dependent adhesion site (MIDAS). So far all attempts to replace the carboxyl group of aspartate with other, pharmacologically favorable isosteric groups have failed. Now it has been shown that a hydroxamic acid group can replace the carboxyl group; the resulting ligand retains its high binding activity. The picture shows one such ligand in the binding site of alphavbeta3.
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Affiliation(s)
- Dominik Heckmann
- Institute for Advanced Study, TU München, Department Chemie, Lichtenbergstrasse 4, 85747 Garching, Germany
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Bruch mit dem Dogma metallkoordinierender Carbonsäuren in Integrinliganden: Änderung von Selektivität und Aktivität durch Hydroxamsäuren als MIDAS-Binder. Angew Chem Int Ed Engl 2009. [DOI: 10.1002/ange.200900206] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Choi H, Jackson NL, Shaw DR, Emanuel PD, Liu YL, Tousson A, Meng Z, Blume SW. mrtl-A translation/localization regulatory protein encoded within the human c-myc locus and distributed throughout the endoplasmic and nucleoplasmic reticular network. J Cell Biochem 2009; 105:1092-108. [PMID: 18816594 DOI: 10.1002/jcb.21909] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
mrtl (myc-related translation/localization regulatory factor) is a previously uncharacterized protein synthesized from the first open reading frame contained within the human c-myc P0 transcript, approximately 800 nucleotides upstream of the Myc coding sequence. The mrtl protein, 114 amino acids in length, is projected to contain an N-terminal transmembrane domain and a highly charged C-terminal interaction domain with homology to numerous RNA-binding proteins. Using monoclonal antibodies raised against the hydrophilic C-terminal domain, endogenous mrtl was visualized in human breast tumor cell lines and primary mammary epithelial cells at the nuclear envelope and contiguous endoplasmic/nucleoplasmic reticulum. mrtl colocalizes and coimmunoprecipitates with translation initiation factor eIF2alpha and the 40S ribosomal protein RACK1, and appears capable of binding specifically to the c-myc RNA. Inducible ectopic overexpression of wild-type mrtl interferes with the function of endogenous mrtl, which results in loss of Myc from the nucleus. Furthermore, treatment of cells with a peptide derived from the C-terminal domain displaces endogenous mrtl and causes a dramatic reduction in total cellular Myc protein levels. Together with our previous work demonstrating complete loss of tumorigenicity in association with ectopic expression of the c-myc P0 5'-UTR (containing the mrtl coding sequence), these results suggest that mrtl may serve an important function in regulating Myc translation and localization to the nucleus, perhaps ultimately contributing to the role of the c-myc locus in oncogenesis.
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Affiliation(s)
- Hyoungsoo Choi
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama 35294, USA
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8
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A new era in prostate cancer therapy: new targets and novel therapeutics. Target Oncol 2007. [DOI: 10.1007/s11523-007-0067-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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9
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Bradley DA, Hussain M, Dipaola RS, Kantoff P. Bone Directed Therapies for Prostate Cancer. J Urol 2007; 178:S42-8. [PMID: 17644119 DOI: 10.1016/j.juro.2007.04.035] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2007] [Accepted: 04/20/2007] [Indexed: 11/29/2022]
Abstract
PURPOSE Bone is the most common site of metastatic disease in prostate cancer and the lead cause of significant morbidity. Preclinical and clinical studies have provided insight into the pathophysiology of bone metastases and the changes that occur in the bone microenvironment that result in a favorable site of growth for prostate cancer. We provide an overview of recent advances in understanding bone biology, and bone targeted therapy research and development. MATERIALS AND METHODS We reviewed recent research findings related to the biology of bone metastases, approaches to targeting osteoclast function, approaches to targeting osteoblasts and advances in assessing the treatment response to bone targeted therapies in the context of prostate cancer management. RESULTS To date targeting some of the key players in the bone microenvironment has not been associated with a significant antitumor effect or with meaningful clinical benefit in phase III randomized trials. A significant limitation in the development of bone targeted therapy has been the inability to objectively assess treatment response. Investigation of improved imaging techniques are ongoing to provide better treatment assessment and, therefore, allow more rapid drug screening and development. CONCLUSIONS It is our recommendation that future therapy development should be combination based, focusing on simultaneous targeting of multiple relevant pathways. Most important of all is the direct targeting of prostate cancer cells.
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Affiliation(s)
- Deborah A Bradley
- Division of Hematology and Oncology, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan 48109, USA
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Zhou Y, Peng H, Ji Q, Qi J, Zhu Z, Yang C. Discovery of small molecule inhibitors of integrin αvβ3 through structure-based virtual screening. Bioorg Med Chem Lett 2006; 16:5878-82. [PMID: 16982193 DOI: 10.1016/j.bmcl.2006.08.061] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2006] [Revised: 07/28/2006] [Accepted: 08/11/2006] [Indexed: 11/15/2022]
Abstract
Inhibitors of integrin alphavbeta3 have been implicated in the treatment of a variety of diseases, including tumor metastasis, neovascularization, osteoporosis, and rheumatoid arthritis. It is therefore desirable to develop new types of small molecule inhibitors of integrin alphavbeta3. Here we describe the discovery of novel classes of small molecule inhibitors, via structure-based virtual screening, that target the ligand binding site of integrin alphavbeta3. Application of the docking procedure for screening of a commercially available compound database resulted in a 1774-fold reduction in the size of the screening set (88695 to 50 compounds) and gave a hit-rate of 14% upon biological evaluation (IC50 value ranging from 30 to 200 microM). The best hit, compound 37, 3,4-dichloro-phenylbiguanide, showed inhibitory activity, in a time- and dose-dependent manner, in both cell motility and angiogenesis assays. Based on the best hit, compound 37, a more effective derivative compound 62 has been identified. Furthermore, molecular graphics analyses of a series of substituted phenylbiguanides were carried out to predict the binding mode between the active compounds and integrin alphavbeta3. Our results indicate that the substituted phenylbiguanides might be involved in the inhibition of bivalent cation-mediated ligand binding of integrin alphavbeta3.
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Affiliation(s)
- Yuan Zhou
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 288 Nanjing Road, Tianjin 300020, PR China
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11
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Talic NF, Evans C, Zaki AM. Inhibition of orthodontically induced root resorption with echistatin, an RGD-containing peptide. Am J Orthod Dentofacial Orthop 2006; 129:252-60. [PMID: 16473718 DOI: 10.1016/j.ajodo.2004.11.030] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2004] [Revised: 11/08/2004] [Accepted: 11/08/2004] [Indexed: 01/08/2023]
Abstract
INTRODUCTION Induced dental root resorption is a common side effect of orthodontic treatment. It is an unpredictable phenomenon, and its etiology is unknown. Odontoclasts responsible for the resorption of the dental tissues--ie, cementum and dentin--share many cytochemical and morphological characteristics with osteoclasts, which are responsible for bone resorption. The aim of this study was to explore cellular mechanisms that decrease induced root resorption in orthodontically treated teeth. METHODS The effects of targeting the alphavbeta3 integrin receptor, expressed by odontoclasts, on induced root resorption surface areas and the number of root resorption lacunae were investigated by using an RGD-containing peptide, echistatin. The effect of echistatin on the number of clast cells in the periodontium was also examined. Tooth movement was achieved in 14 Sprague-Dawley rats by placing elastic bands between the right maxillary first and second molars for 24 hours. The animals were equally divided into 2 groups; the experimental animals received echistatin intravenously for 8 hours (0.8 microg/kg/min), and the controls received sterile water. The specimens obtained were processed for light microscopy. The surface area and the number of root resorption lacunae were measured histomorphometrically by using digital photomicrographs. Echistatin labeled with a fluorescent marker was used to confirm its presence in clast cells with fluorescent microscopy. Cytochemically, tartrate-resistant acid phosphatase was used to quantify mature and committed clast cells. Echistatin was localized in targeted cells in the periodontium. RESULTS Echistatin significantly decreased root resorption surface areas (P < .01) and reduced the number of root resorption lacunae (P < .01). There was no statistically significant difference in clast cell numbers. CONCLUSIONS Targeting alphavbeta3 integrin receptor expressed by odontoclasts can be effective in reducing root resorption during tooth movement. Further studies are needed to elucidate the mechanism of this inhibition.
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Affiliation(s)
- Nabeel F Talic
- Orthodontic Division, Department of Preventive Dentistry, King Saud University, Riyadh, Saudi Arabia
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Schaller S, Henriksen K, Hoegh-Andersen P, Søndergaard BC, Sumer EU, Tanko LB, Qvist P, Karsdal MA. In Vitro, Ex Vivo, andIn VivoMethodological Approaches for Studying Therapeutic Targets of Osteoporosis and Degenerative Joint Diseases: How Biomarkers Can Assist? Assay Drug Dev Technol 2005; 3:553-80. [PMID: 16305312 DOI: 10.1089/adt.2005.3.553] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Although our approach to the clinical management of osteoporosis (OP) and degenerative joint diseases (DJD)-major causes of disability and morbidity in the elderly-has greatly advanced in the past decades, curative treatments that could bring ultimate solutions have yet to be found or developed. Effective and timely development of candidate drugs is a critical function of the availability of sensitive and accurate methodological arsenal enabling the recognition and quantification of pharmacodynamic effects. The established concept that both OP and DJD arise from an imbalance in processes of tissue formation and degradation draws attention to need of establishing in vitro, ex vivo, and in vivo experimental settings, which allow obtaining insights into the mechanisms driving increased bone and cartilage degradation at cellular, organ, and organism levels. When addressing changes in bone or cartilage turnover at the organ or organism level, monitoring tools adequately reflecting the outcome of tissue homeostasis become particularly critical. In this context, bioassays targeting the quantification of various degradation and formation products of bone and cartilage matrix elements represent a useful approach. In this review, a comprehensive overview of widely used and recently established in vitro, ex vivo, and in vivo set-ups is provided, which in many cases effectively take advantage of the potentials of biomarkers. In addition to describing and discussing the advantages and limitations of each assay and their methods of evaluation, we added experimental and clinical data illustrating the utility of biomarkers for these methodological approaches.
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Nakagawa H, Takami M, Udagawa N, Sawae Y, Suda K, Sasaki T, Takahashi N, Wachi M, Nagai K, Woo JT. Destruxins, cyclodepsipeptides, block the formation of actin rings and prominent clear zones and ruffled borders in osteoclasts. Bone 2003; 33:443-55. [PMID: 13678787 DOI: 10.1016/s8756-3282(03)00201-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Bone-resorbing osteoclasts exhibit polarized morphological structures such as actin rings, clear zones, and ruffled borders. To gain insight into the mechanism of bone-resorbing activity of osteoclast and to discover new types of anti-resorptive agents, we have screened for natural compounds that inhibit the bone-resorbing activity of osteoclast-like multinucleated cells (OCLs). Destruxin B (DestB) and E (DestE), cyclodepsipeptides, were found to inhibit pit formation without affecting osteoclast differentiation and survival. Destruxins reversibly induced morphological changes in OCLs in a dose-dependent manner (DestB, 0.2-1 microM; DestE, 0.01-0.05 microM) and inhibited pit formation. Destruxin-induced morphological changes were accompanied by disruption of the actin rings in OCLs. The formation of actin rings in OCLs after adhesion was also inhibited by destruxins. Electron microscopical analysis revealed that destruxin-treated OCLs on dentine slices have no prominent clear zones and ruffled borders. The effective concentrations of destruxins on the morphological changes were almost the same as those that inhibited bone resorption in organ culture system. These results suggest that the anti-resorptive effects of destruxins result from induction of a disorder of the morphological structures in polarized OCLs.
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Affiliation(s)
- H Nakagawa
- Department of Bioengineering, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan
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Moalli MR, Wang S, Caldwell NJ, Patil PV, Maynard CR. Mechanical stimulation induces pp125(FAK) and pp60(src) activity in an in vivo model of trabecular bone formation. J Appl Physiol (1985) 2001; 91:912-8. [PMID: 11457810 DOI: 10.1152/jappl.2001.91.2.912] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Utilizing an in vivo model of trabecular bone formation, we demonstrated the temporal and spatial activation of pp125(FAK) in response to specific mechanical load stimuli. Bone chambers equipped with hydraulic actuators were aseptically inserted into each proximal tibial metaphysis of adult, male dogs under general anesthesia. The load stimulus consisted of a trapezoidal waveform, with a maximum compressive load of 17.8 N, loading rate of 89 N/s, at 1 Hz frequency. One chamber was loaded for 2 (120 cycles), 15 (900 cycles), or 30 min (1,800 cycles), whereas the contralateral chamber served as unloaded control. Bone chambers were biopsied at postload time points of 0, 15, and 45 min. Load-induced activation of FAK was rapid, and the duration of activation was dependent on the number of applied load cycles. Mechanical stimulation increased the association of FAK with Src and the time course of complex formation paralleled the temporal activation of FAK. Evaluation of cryosections revealed prominent FAK immunoreactivity among marrow fibroblasts and stromal cells.
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Affiliation(s)
- M R Moalli
- Orthopaedic Research Laboratories, Department of Orthopaedic Surgery, University of Michigan, Ann Arbor, Michigan 48109, USA.
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Violette SM, Guan W, Bartlett C, Smith JA, Bardelay C, Antoine E, Rickles RJ, Mandine E, van Schravendijk MR, Adams SE, Lynch BA, Shakespeare WC, Yang M, Jacobsen VA, Takeuchi CS, Macek KJ, Bohacek RS, Dalgarno DC, Weigele M, Lesuisse D, Sawyer TK, Baron R. Bone-targeted Src SH2 inhibitors block Src cellular activity and osteoclast-mediated resorption. Bone 2001; 28:54-64. [PMID: 11165943 DOI: 10.1016/s8756-3282(00)00427-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Src, a nonreceptor tyrosine kinase, is an important regulator of osteoclast-mediated resorption. We have investigated whether compounds that bind to the Src SH2 domain inhibit Src activity in cells and decrease osteoclast-mediated resorption. Compounds were examined for binding to the Src SH2 domain in vitro using a fluorescence polarization binding assay. Experiments were carried out with compounds demonstrating in vitro binding activity (nmol/L range) to determine if they inhibit Src SH2 binding and Src function in cells, demonstrate blockade of Src signaling, and lack cellular toxicity. Cell-based assays included: (1) a mammalian two-hybrid assay; (2) morphological reversion and growth inhibition of cSrcY527F-transformed cells; and (3) inhibition of cortactin phosphorylation in csk-/- cells. The Src SH2 binding compounds inhibit Src activity in all three of these mechanism-based assays. The compounds described were synthesized to contain nonhydrolyzable phosphotyrosine mimics that bind to bone. These compounds were further tested and found to inhibit rabbit osteoclast-mediated resorption of dentine. These results indicate that compounds that bind to the Src SH2 domain can inhibit Src activity in cells and inhibit osteoclast-mediated resorption.
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Affiliation(s)
- S M Violette
- ARIAD Pharmaceuticals Inc., Cambridge, MA 02139, USA
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An adherent condition is required for formation of multinuclear osteoclasts in the presence of macrophage colony-stimulating factor and receptor activator of nuclear factor κB ligand. Blood 2000. [DOI: 10.1182/blood.v96.13.4335.h8004335_4335_4343] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Identification of receptor activator of nuclear factor-κB (RANK) and RANK-ligand (RANKL) has provided new insights into the osteoclast differentiation pathway. Osteoclast precursor cells were isolated using monoclonal antibodies against c-Fms and RANK, and the effect of adherence on the in vitro differentiation and proliferation of these cells was examined in 2 different types of stromal-cell–free culture systems: a semisolid culture medium (a nonadherent system) and a liquid culture medium (an adherent system). Osteoclast precursor cells were not able to differentiate into mature osteoclasts efficiently in the semisolid culture system. Trimerized RANKL enhanced osteoclast differentiation in semisolid cultures, but not to the extent seen when cells were allowed to adhere to plastic. Initial precursor cells were capable of differentiating into macrophages or osteoclasts. Once these cells were transferred to adherent conditions, striking differentiation was induced. Multinuclear cells were observed even after they had displayed phagocytic activity, which suggests that cell adhesion plays an important role in the differentiation of osteoclast precursor cells. Integrins, especially the arginine-glycine-aspartic acid (RGD)–recognizing integrins αv and β3, were needed for osteoclast-committed precursor cells to proliferate in order to form multinuclear osteoclasts, and the increase in cell density affected the formation of multinuclear cells. A model of osteoclast differentiation with 2 stages of precursor development is proposed: (1) a first stage, in which precursor cells are bipotential and capable of anchorage-independent growth, and (2) a second stage, in which the further proliferation and differentiation of osteoclast-committed precursor cells is anchorage-dependent.
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An adherent condition is required for formation of multinuclear osteoclasts in the presence of macrophage colony-stimulating factor and receptor activator of nuclear factor κB ligand. Blood 2000. [DOI: 10.1182/blood.v96.13.4335] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
Identification of receptor activator of nuclear factor-κB (RANK) and RANK-ligand (RANKL) has provided new insights into the osteoclast differentiation pathway. Osteoclast precursor cells were isolated using monoclonal antibodies against c-Fms and RANK, and the effect of adherence on the in vitro differentiation and proliferation of these cells was examined in 2 different types of stromal-cell–free culture systems: a semisolid culture medium (a nonadherent system) and a liquid culture medium (an adherent system). Osteoclast precursor cells were not able to differentiate into mature osteoclasts efficiently in the semisolid culture system. Trimerized RANKL enhanced osteoclast differentiation in semisolid cultures, but not to the extent seen when cells were allowed to adhere to plastic. Initial precursor cells were capable of differentiating into macrophages or osteoclasts. Once these cells were transferred to adherent conditions, striking differentiation was induced. Multinuclear cells were observed even after they had displayed phagocytic activity, which suggests that cell adhesion plays an important role in the differentiation of osteoclast precursor cells. Integrins, especially the arginine-glycine-aspartic acid (RGD)–recognizing integrins αv and β3, were needed for osteoclast-committed precursor cells to proliferate in order to form multinuclear osteoclasts, and the increase in cell density affected the formation of multinuclear cells. A model of osteoclast differentiation with 2 stages of precursor development is proposed: (1) a first stage, in which precursor cells are bipotential and capable of anchorage-independent growth, and (2) a second stage, in which the further proliferation and differentiation of osteoclast-committed precursor cells is anchorage-dependent.
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Violette SM, Shakespeare WC, Bartlett C, Guan W, Smith JA, Rickles RJ, Bohacek RS, Holt DA, Baron R, Sawyer TK. A Src SH2 selective binding compound inhibits osteoclast-mediated resorption. CHEMISTRY & BIOLOGY 2000; 7:225-35. [PMID: 10712930 DOI: 10.1016/s1074-5521(00)00090-9] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
BACKGROUND The observations that Src(-/-) mice develop osteopetrosis and Src family tyrosine kinase inhibitors decrease osteoclast-mediated resorption of bone have implicated Src in the regulation of osteoclast-resorptive activity. We have designed and synthesized a compound, AP22161, that binds selectively to the Src SH2 domain and demonstrated that it inhibits Src-dependent cellular activity and inhibits osteoclast-mediated resorption. RESULTS AP22161 was designed to bind selectively to the Src SH2 domain by targeting a cysteine residue within the highly conserved phosphotyrosine-binding pocket. AP22161 was tested in vitro for binding to SH2 domains and was found to bind selectively and with high affinity to the Src SH2 domain. AP22161 was further tested in mechanism-based cellular assays and found to block Src SH2 binding to peptide ligands, inhibit Src-dependent cellular activity and diminish osteoclast resorptive activity. CONCLUSIONS These results indicate that a compound that selectively inhibits Src SH2 binding can be used to inhibit osteoclast resorption. Furthermore, AP22161 has the potential to be further developed for treating osteoporosis.
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Affiliation(s)
- S M Violette
- ARIAD Pharmaceuticals Inc., Biogen, Cambridge, Cambridge, MA 02139, USA.
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Li P, Selvaraj P, Zhu C. Analysis of competition binding between soluble and membrane-bound ligands for cell surface receptors. Biophys J 1999; 77:3394-406. [PMID: 10585962 PMCID: PMC1300611 DOI: 10.1016/s0006-3495(99)77171-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Binding of the Fc portion of IgG coated on targets to Fcgamma receptors (e.g., CD16) expressed on leukocytes (i.e., 2D binding) is an initiating step for immune responses such as phagocytosis or antibody-dependent cellular cytotoxicity. In vivo, circulating leukocytes are exposed to plasma IgG. The competition from soluble IgG (i.e., 3D binding) may affect the 2D binding. Many cell surface receptors, CD16 included, have soluble counterparts. While their physiological significance is not clear, receptor-based competitive inhibition therapy, in which soluble receptors, ligands, and their analogs are employed to compete with surface-bound receptors and ligands to prevent unwanted adhesion, is widely used to treat various diseases. To provide a quantitative basis for design of these therapeutic approaches, we developed a mathematical model for 2D and 3D competition binding. The model relates cell-surface adhesion (in the presence and absence of dislodging forces) to the concentration of the soluble competitor, the densities of the surface-bound receptors and ligands, as well as the binding affinities of the 2D and 3D interactions. Binding of CD16-expressing cells to an IgG-coated surface in the presence of a soluble competitor (IgG or anti-CD16 antibody) was quantified by a centrifugation assay. The agreement between experiment and theory supports the validity of the model, which could be useful in predicting the efficacy of the competitor.
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Affiliation(s)
- P Li
- George W. Woodruff School of Mechanical Engineering and Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0363, USA
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Haubner R, Kessler IH. Stereoisomere Peptid-Bibliotheken und Peptidmimetika zum Design von selektiven Inhibitoren des αv β3-Integrins für eine neuartige Krebstherapie. Angew Chem Int Ed Engl 1997. [DOI: 10.1002/ange.19971091304] [Citation(s) in RCA: 77] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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21
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Corbett JW, Graciani NR, Mousa SA, DeGrado WF. Solid-phase synthesis of a selective αvβ3 integrin antagonist library. Bioorg Med Chem Lett 1997. [DOI: 10.1016/s0960-894x(97)00200-x] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Cao X, Teitelbaum SL, Zhu HJ, Zhang L, Feng X, Ross FP. Competition for a unique response element mediates retinoic acid inhibition of vitamin D3-stimulated transcription. J Biol Chem 1996; 271:20650-4. [PMID: 8702813 DOI: 10.1074/jbc.271.34.20650] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
We have identified a novel steroid hormone response element in the avian beta3 integrin promoter. This sequence, comprising three hexameric direct repeat half-sites separated by nine and three nucleotides binds vitamin D receptor (VDR)-retinoid X receptor (RXR) and retinoic acid receptor (RAR)-RXR heterodimers. VDR-RXR binds direct repeats separated by three base pairs, and RAR-RXR recognizes half-sites separated by nine bases, whereas the central half-site interacts with both heterodimers. Retinoic acid and 1, 25-dihydroxyvitamin D3 activate both a genomic fragment including the transcriptional start site and an oligonucleotide containing the three repeats, linked to a heterologous promoter. Co-addition of the steroids produces neither synergy nor an additive effect; rather the result equals that for retinoic acid alone. Scatchard analysis demonstrates that RAR-RXR has greater affinity than VDR-RXR for the composite element. Based on these findings we propose a model in which there is specific, polarity-defined binding of VDR-RXR and RAR-RXR to three half-sites, which form two overlapping steroid response elements, with the central half-site common to both. Our results identify a novel mechanism by which one steroid hormone can modulate the activity of a second, by competing for a shared half-site in a composite response element.
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Affiliation(s)
- X Cao
- Department of Pathology, Washington University School of Medicine, St. Louis, Missouri 63110, USA
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23
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Chapter 20. Cell Adhesion Integrins as Pharmaceutical Targets. ANNUAL REPORTS IN MEDICINAL CHEMISTRY 1996. [DOI: 10.1016/s0065-7743(08)60459-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register]
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