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Badea CT. Principles of Micro X-ray Computed Tomography. Mol Imaging 2021. [DOI: 10.1016/b978-0-12-816386-3.00006-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Wada M, Shimada Y, Iizuka S, Ishii N, Hiraki H, Tachibana T, Maeda K, Saito M, Arakawa S, Ishimoto T, Nakano T, Ida H, Ohashi T, Kobayashi H. Ex Vivo Gene Therapy Treats Bone Complications of Mucopolysaccharidosis Type II Mouse Models through Bone Remodeling Reactivation. Mol Ther Methods Clin Dev 2020; 19:261-274. [PMID: 33102618 PMCID: PMC7567932 DOI: 10.1016/j.omtm.2020.09.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 09/16/2020] [Indexed: 01/22/2023]
Abstract
Mucopolysaccharidosis type II is a disease caused by organ accumulation of glycosaminoglycans due to iduronate 2-sulfatase deficiency. This study investigated the pathophysiology of the bone complications associated with mucopolysaccharidosis II and the effect of lentivirus-mediated gene therapy of hematopoietic stem cells on bone lesions of mucopolysaccharidosis type II mouse models in comparison with enzyme replacement therapy. Bone volume, density, strength, and trabecular number were significantly higher in the untreated mucopolysaccharidosis type II mice than in wild-type mice. Accumulation of glycosaminoglycans caused reduced bone metabolism. Specifically, persistent high serum iduronate 2-sulfatase levels and release of glycosaminoglycans from osteoblasts and osteoclasts in mucopolysaccharidosis type II mice that had undergone gene therapy reactivated bone lineage remodeling, subsequently reducing bone mineral density, strength, and trabecular number to a similar degree as that observed in wild-type mice. Bone formation, resorption parameters, and mineral density in the diaphysis edge did not appear to have been affected by the irradiation administered as a pre-treatment for gene therapy. Hence, the therapeutic effect of gene therapy on the bone complications of mucopolysaccharidosis type II mice possibly outweighed that of enzyme replacement therapy in many aspects.
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Affiliation(s)
- Miho Wada
- Department of Pediatrics, The Jikei University School of Medicine, Tokyo, Japan.,Division of Gene Therapy, Research Center for Medicine Sciences, The Jikei University School of Medicine, Tokyo, Japan
| | - Yohta Shimada
- Division of Gene Therapy, Research Center for Medicine Sciences, The Jikei University School of Medicine, Tokyo, Japan
| | - Sayoko Iizuka
- Division of Gene Therapy, Research Center for Medicine Sciences, The Jikei University School of Medicine, Tokyo, Japan
| | - Natsumi Ishii
- Division of Gene Therapy, Research Center for Medicine Sciences, The Jikei University School of Medicine, Tokyo, Japan
| | - Hiromi Hiraki
- Division of Gene Therapy, Research Center for Medicine Sciences, The Jikei University School of Medicine, Tokyo, Japan
| | - Toshiaki Tachibana
- Division of Molecular Cell Biology, Research Center for Medical Science, The Jikei University School of Medicine, Tokyo, Japan
| | - Kazuhiro Maeda
- Department of Orthopaedic Surgery, The Jikei University School of Medicine, Tokyo, Japan
| | - Mitsuru Saito
- Department of Orthopaedic Surgery, The Jikei University School of Medicine, Tokyo, Japan
| | - Shoutaro Arakawa
- Department of Orthopaedic Surgery, The Jikei University School of Medicine, Tokyo, Japan
| | - Takuya Ishimoto
- Biomaterials & Structural Materials Design Area, Course of Materials Science & Engineering, Division of Materials & Manufacturing Science, Graduate School of Engineering, Osaka University, Osaka, Japan
| | - Takayoshi Nakano
- Biomaterials & Structural Materials Design Area, Course of Materials Science & Engineering, Division of Materials & Manufacturing Science, Graduate School of Engineering, Osaka University, Osaka, Japan
| | - Hiroyuki Ida
- Department of Pediatrics, The Jikei University School of Medicine, Tokyo, Japan.,Division of Gene Therapy, Research Center for Medicine Sciences, The Jikei University School of Medicine, Tokyo, Japan
| | - Toya Ohashi
- Department of Pediatrics, The Jikei University School of Medicine, Tokyo, Japan.,Division of Gene Therapy, Research Center for Medicine Sciences, The Jikei University School of Medicine, Tokyo, Japan
| | - Hiroshi Kobayashi
- Department of Pediatrics, The Jikei University School of Medicine, Tokyo, Japan.,Division of Gene Therapy, Research Center for Medicine Sciences, The Jikei University School of Medicine, Tokyo, Japan
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Govey PM, Zhang Y, Donahue HJ. Mechanical Loading Attenuates Radiation-Induced Bone Loss in Bone Marrow Transplanted Mice. PLoS One 2016; 11:e0167673. [PMID: 27936104 PMCID: PMC5147933 DOI: 10.1371/journal.pone.0167673] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Accepted: 11/20/2016] [Indexed: 12/16/2022] Open
Abstract
Exposure of bone to ionizing radiation, as occurs during radiotherapy for some localized malignancies and blood or bone marrow cancers, as well as during space travel, incites dose-dependent bone morbidity and increased fracture risk. Rapid trabecular and endosteal bone loss reflects acutely increased osteoclastic resorption as well as decreased bone formation due to depletion of osteoprogenitors. Because of this dysregulation of bone turnover, bone’s capacity to respond to a mechanical loading stimulus in the aftermath of irradiation is unknown. We employed a mouse model of total body irradiation and bone marrow transplantation simulating treatment of hematologic cancers, hypothesizing that compression loading would attenuate bone loss. Furthermore, we hypothesized that loading would upregulate donor cell presence in loaded tibias due to increased engraftment and proliferation. We lethally irradiated 16 female C57Bl/6J mice at age 16 wks with 10.75 Gy, then IV-injected 20 million GFP(+) total bone marrow cells. That same day, we initiated 3 wks compression loading (1200 cycles 5x/wk, 10 N) in the right tibia of 10 of these mice while 6 mice were irradiated, non-mechanically-loaded controls. As anticipated, before-and-after microCT scans demonstrated loss of trabecular bone (-48.2% Tb.BV/TV) and cortical thickness (-8.3%) at 3 wks following irradiation. However, loaded bones lost 31% less Tb.BV/TV and 8% less cortical thickness (both p<0.001). Loaded bones also had significant increases in trabecular thickness and tissue mineral densities from baseline. Mechanical loading did not affect donor cell engraftment. Importantly, these results demonstrate that both cortical and trabecular bone exposed to high-dose therapeutic radiation remain capable of an anabolic response to mechanical loading. These findings inform our management of bone health in cases of radiation exposure.
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Affiliation(s)
- Peter M. Govey
- Division of Musculoskeletal Sciences, Department of Orthopaedics and Rehabilitation, Penn State College of Medicine, Hershey, PA, United States of America
- Department of Biomedical Engineering, Penn State College of Engineering, University Park, PA, United States of America
| | - Yue Zhang
- Division of Musculoskeletal Sciences, Department of Orthopaedics and Rehabilitation, Penn State College of Medicine, Hershey, PA, United States of America
- Department of Biomedical Engineering, Virginia Commonwealth College of Engineering, Richmond, VA, United States of America
| | - Henry J. Donahue
- Division of Musculoskeletal Sciences, Department of Orthopaedics and Rehabilitation, Penn State College of Medicine, Hershey, PA, United States of America
- Department of Biomedical Engineering, Penn State College of Engineering, University Park, PA, United States of America
- Department of Cellular and Molecular Physiology, Penn State College of Medicine, Hershey, PA, United States of America
- Department of Biomedical Engineering, Virginia Commonwealth College of Engineering, Richmond, VA, United States of America
- * E-mail:
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Abstract
Computed tomography (CT) is one of the most valuable modalities for in vivo imaging because it is fast, high-resolution, cost-effective, and non-invasive. Moreover, CT is heavily used not only in the clinic (for both diagnostics and treatment planning) but also in preclinical research as micro-CT. Although CT is inherently effective for lung and bone imaging, soft tissue imaging requires the use of contrast agents. For small animal micro-CT, nanoparticle contrast agents are used in order to avoid rapid renal clearance. A variety of nanoparticles have been used for micro-CT imaging, but the majority of research has focused on the use of iodine-containing nanoparticles and gold nanoparticles. Both nanoparticle types can act as highly effective blood pool contrast agents or can be targeted using a wide variety of targeting mechanisms. CT imaging can be further enhanced by adding spectral capabilities to separate multiple co-injected nanoparticles in vivo. Spectral CT, using both energy-integrating and energy-resolving detectors, has been used with multiple contrast agents to enable functional and molecular imaging. This review focuses on new developments for in vivo small animal micro-CT using novel nanoparticle probes applied in preclinical research.
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Affiliation(s)
- Jeffrey R Ashton
- Department of Biomedical Engineering, Duke University, Durham NC, USA ; Department of Radiology, Center for In Vivo Microscopy, Duke University Medical Center, Durham NC, USA
| | - Jennifer L West
- Department of Biomedical Engineering, Duke University, Durham NC, USA
| | - Cristian T Badea
- Department of Radiology, Center for In Vivo Microscopy, Duke University Medical Center, Durham NC, USA
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Kłodowski K, Kamiński J, Nowicka K, Tarasiuk J, Wroński S, Świętek M, Błażewicz M, Figiel H, Turek K, Szponder T. Micro-imaging of implanted scaffolds using combined MRI and micro-CT. Comput Med Imaging Graph 2014; 38:458-68. [DOI: 10.1016/j.compmedimag.2014.06.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Revised: 04/15/2014] [Accepted: 06/13/2014] [Indexed: 11/19/2022]
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Abstract
Micron-scale computed tomography (micro-CT) is an essential tool for phenotyping and for elucidating diseases and their therapies. This work is focused on preclinical micro-CT imaging, reviewing relevant principles, technologies, and applications. Commonly, micro-CT provides high-resolution anatomic information, either on its own or in conjunction with lower-resolution functional imaging modalities such as positron emission tomography (PET) and single-photon emission computed tomography (SPECT). More recently, however, advanced applications of micro-CT produce functional information by translating clinical applications to model systems (e.g., measuring cardiac functional metrics) and by pioneering new ones (e.g. measuring tumor vascular permeability with nanoparticle contrast agents). The primary limitations of micro-CT imaging are the associated radiation dose and relatively poor soft tissue contrast. We review several image reconstruction strategies based on iterative, statistical, and gradient sparsity regularization, demonstrating that high image quality is achievable with low radiation dose given ever more powerful computational resources. We also review two contrast mechanisms under intense development. The first is spectral contrast for quantitative material discrimination in combination with passive or actively targeted nanoparticle contrast agents. The second is phase contrast which measures refraction in biological tissues for improved contrast and potentially reduced radiation dose relative to standard absorption imaging. These technological advancements promise to develop micro-CT into a commonplace, functional and even molecular imaging modality.
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Affiliation(s)
- D P Clark
- Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Box 3302, Durham, NC 27710, USA
| | - C T Badea
- Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Box 3302, Durham, NC 27710, USA.
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Campbell GM, Sophocleous A. Quantitative analysis of bone and soft tissue by micro-computed tomography: applications to ex vivo and in vivo studies. Bonekey Rep 2014; 3:564. [PMID: 25184037 DOI: 10.1038/bonekey.2014.59] [Citation(s) in RCA: 93] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Accepted: 06/12/2014] [Indexed: 12/20/2022]
Abstract
Micro-computed tomography (micro-CT) is a high-resolution imaging modality that is capable of analysing bone structure with a voxel size on the order of 10 μm. With the development of in vivo micro-CT, where disease progression and treatment can be monitored in a living animal over a period of time, this modality has become a standard tool for preclinical assessment of bone architecture during disease progression and treatment. For meaningful comparison between micro-CT studies, it is essential that the same parameters for data acquisition and analysis methods be used. This protocol outlines the common procedures that are currently used for sample preparation, scanning, reconstruction and analysis in micro-CT studies. Scan and analysis methods for trabecular and cortical bone are covered for the femur, tibia, vertebra and the full neonate body of small rodents. The analysis procedures using the software provided by ScancoMedical and Bruker are discussed, and the routinely used bone architectural parameters are outlined. This protocol also provides a section dedicated to in vivo scanning and analysis, which covers the topics of anaesthesia, radiation dose and image registration. Because of the expanding research using micro-CT to study other skeletal sites, as well as soft tissues, we also provide a review of current techniques to examine the skull and mandible, adipose tissue, vasculature, tumour severity and cartilage. Lists of recommended further reading and literature references are included to provide the reader with more detail on the methods described.
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Hsu JT, Wang SP, Huang HL, Chen YJ, Wu J, Tsai MT. The assessment of trabecular bone parameters and cortical bone strength: A comparison of micro-CT and dental cone-beam CT. J Biomech 2013; 46:2611-8. [DOI: 10.1016/j.jbiomech.2013.08.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2013] [Revised: 08/15/2013] [Accepted: 08/16/2013] [Indexed: 11/26/2022]
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Hsu JT, Chen YJ, Tsai MT, Lan HHC, Cheng FC, Chen MYC, Wang SP. Predicting cortical bone strength from DXA and dental cone-beam CT. PLoS One 2012; 7:e50008. [PMID: 23226234 PMCID: PMC3511426 DOI: 10.1371/journal.pone.0050008] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2012] [Accepted: 10/15/2012] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE This study compared the capabilities of dual-energy X-ray absorptiometry (DXA) and dental cone-beam computed tomography (CBCT) for predicting the cortical bone strength of rat femurs and tibias. MATERIALS AND METHODS Specimens of femurs and tibias obtained from 14 rats were first scanned with DXA to obtain the areal bone mineral density (BMD) of the midshaft cortical portion of the bones. The bones were then scanned using dental CBCT to measure the volumetric cortical bone mineral density (vCtBMD) and the cross-sectional moment of inertia (CSMI) for calculating the bone strength index (BSI). A three-point bending test was conducted to measure the fracture load of each femur and tibia. Bivariate linear Pearson analysis was used to calculate the correlation coefficients (r values) among the CBCT measurements, DXA measurements, and three-point bending parameters. RESULTS The correlation coefficients for the associations of the fracture load with areal BMD (measured using DXA), vCtBMD (measured using CBCT), CSMI (measured using CBCT), and BSI were 0.585 (p = 0.028) and 0.532 (p = 0.050) (for the femur and tibia, respectively), 0.638 (p = 0.014) and 0.762 (p = 0.002), 0.778 (p = 0.001) and 0.792 (p<0.001), and 0.822 (p<0.001) and 0.842 (p<0.001), respectively. CONCLUSIONS CBCT was found to be superior to DXA for predicting cortical bone fracture loads in rat femurs and tibias. The BSI, which is a combined index of densitometric and geometric parameters, was especially useful. Further clinical studies are needed to validate the predictive value of BSI obtained from CBCT and should include testing on human cadaver specimens.
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Affiliation(s)
- Jui-Ting Hsu
- School of Dentistry, College of Medicine, China Medical University, Taichung, Taiwan
| | - Ying-Ju Chen
- Stem Cell Center, Department of Medical Research, Taichung Veterans General Hospital, Taichung, Taiwan
| | - Ming-Tzu Tsai
- Department of Biomedical Engineering, Hungkuang University, Taichung, Taiwan
| | - Howard Haw-Chang Lan
- Department of Radiology, Taichung Veterans General Hospital, Taichung, Taiwan
- School of Radiological Technology, Central Taiwan University of Science and Technology, Taichung, Taiwan
| | - Fu-Chou Cheng
- Stem Cell Center, Department of Medical Research, Taichung Veterans General Hospital, Taichung, Taiwan
| | - Michael Y. C. Chen
- School of Dentistry, College of Medicine, China Medical University, Taichung, Taiwan
| | - Shun-Ping Wang
- Department of Orthopaedics, Taichung Veterans General Hospital, Taichung, Taiwan
- * E-mail:
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Green DE, Adler BJ, Chan ME, Rubin CT. Devastation of adult stem cell pools by irradiation precedes collapse of trabecular bone quality and quantity. J Bone Miner Res 2012; 27:749-59. [PMID: 22190044 DOI: 10.1002/jbmr.1505] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Stem cell depletion and compromised bone marrow resulting from radiation exposure fosters long-term deterioration of numerous physiologic systems, with the degradation of the skeletal system ultimately increasing the risk of fractures. To study the interrelationship of damaged bone marrow cell populations with trabecular microarchitecture, 8- and 16-week-old C57BL/6 male mice were sublethally irradiated with 5 Gy of (137)Cs γ-rays, and adult stem cells residing in the bone marrow, as well as bone quantity and quality, were evaluated in the proximal tibia after 2 days, 10 days, and 8 weeks compared with age-matched controls. Total extracted bone marrow cells in the irradiated 8-week, young adult mice, including the hematopoietic cell niches, collapsed by 65% ± 11% after 2 days, remaining at those levels through 10 days, only recovering to age-matched control levels by 8 weeks. As early as 10 days, double-labeled surface was undetectable in the irradiated group, paralleled by a 41% ± 12% and 33% ± 4% decline in bone volume fraction (BV/TV) and trabecular number (Tb.N), respectively, and a 50% ± 10% increase in trabecular separation (Tb.Sp) compared with the age-matched controls, a compromised structure that persisted to 8 weeks postirradiation. Although the overall collapse of the bone marrow population and devastation of bone quality was similar between the "young adult" and "mature" mice, the impact of irradiation--and the speed of recovery--on specific hematopoietic subpopulations was dependent on age, with the older animals slower to restore key progenitor populations. These data indicate that, independent of animal age, complications arising from irradiation extend beyond the collapse of the stem cell population and extend toward damage to key organ systems. It is reasonable to presume that accelerating the recovery of these stem cell pools will enable the prompt repair of the skeletal system and ultimately reduce the susceptibility to fractures.
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Affiliation(s)
- Danielle E Green
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY 11794-2580, USA
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Levaot N, Simoncic PD, Dimitriou ID, Scotter A, La Rose J, Ng AHM, Willett TL, Wang CJ, Janmohamed S, Grynpas M, Reichenberger E, Rottapel R. 3BP2-deficient mice are osteoporotic with impaired osteoblast and osteoclast functions. J Clin Invest 2011; 121:3244-57. [PMID: 21765218 DOI: 10.1172/jci45843] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2010] [Accepted: 06/01/2011] [Indexed: 12/29/2022] Open
Abstract
A fine balance between bone resorption by osteoclasts and bone formation by osteoblasts maintains bone homeostasis. In patients with cherubism, gain-of-function mutations in 3BP2, which is encoded by SH3-domain binding protein 2 (SH3BP2), cause cystic lesions with activated osteoclasts that lead to craniofacial abnormalities. However, little is known about the function of wild-type 3BP2 in regulating bone homeostasis. Here we have shown that 3BP2 is required for the normal function of both osteoblasts and osteoclasts. Initial analysis showed that Sh3bp2-/-mice developed osteoporosis as a result of reduced bone formation despite the fact that bone resorption was impaired. We demonstrated using reciprocal bone marrow chimeras, a cell-intrinsic defect of the osteoblast and osteoclast compartments in vivo. Further, Sh3bp2-/- osteoblasts failed to mature and form mineralized nodules in vitro, while Sh3bp2-/- osteoclasts spread poorly and were unable to effectively degrade dentine matrix in vitro. Finally, we showed that 3BP2 was required for Abl activation in osteoblasts and Src activation in osteoclasts, and demonstrated that the in vitro defect of each cell type was restored by the respective expression of activated forms of these kinases. These findings reveal an unanticipated role for the 3BP2 adapter protein in osteoblast function and in coordinating bone homeostatic signals in both osteoclast and osteoblast lineages.
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Affiliation(s)
- Noam Levaot
- Campbell Family Cancer Research Institute, Ontario Cancer Institute, Princess Margaret Hospital, University Health Network, Department of Medicine, University of Toronto, Toronto, Ontario, Canada
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Kagadis GC, Loudos G, Katsanos K, Langer SG, Nikiforidis GC. In vivosmall animal imaging: Current status and future prospects. Med Phys 2010; 37:6421-42. [DOI: 10.1118/1.3515456] [Citation(s) in RCA: 108] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
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Hirbe AC, Roelofs AJ, Floyd DH, Deng H, Becker SN, Lanigan LG, Apicelli AJ, Xu Z, Prior JL, Eagleton MC, Piwnica-Worms D, Rogers MJ, Weilbaecher K. The bisphosphonate zoledronic acid decreases tumor growth in bone in mice with defective osteoclasts. Bone 2009; 44:908-16. [PMID: 19442620 PMCID: PMC2782613 DOI: 10.1016/j.bone.2009.01.010] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2008] [Revised: 10/16/2008] [Accepted: 01/06/2009] [Indexed: 01/01/2023]
Abstract
Bisphosphonates (BPs), bone targeted drugs that disrupt osteoclast function, are routinely used to treat complications of bone metastasis. Studies in preclinical models of cancer have shown that BPs reduce skeletal tumor burden and increase survival. Similarly, we observed in the present study that administration of the Nitrogen-containing BP (N-BP), zoledronic acid (ZA) to osteolytic tumor-bearing Tax+ mice beginning at 6 months of age led to resolution of radiographic skeletal lesions. N-BPs inhibit farnesyl diphosphate (FPP) synthase, thereby inhibiting protein prenylation and causing cellular toxicity. We found that ZA decreased Tax+ tumor and B16 melanoma viability and caused the accumulation of unprenylated Rap1a proteins in vitro. However, it is presently unclear whether N-BPs exert anti-tumor effects in bone independent of inhibition of osteoclast (OC) function in vivo. Therefore, we evaluated the impact of treatment with ZA on B16 melanoma bone tumor burden in irradiated mice transplanted with splenic cells from src(-/-) mice, which have non-functioning OCs. OC-defective mice treated with ZA demonstrated a significant 88% decrease in tumor growth in bone compared to vehicle-treated OC-defective mice. These data support an osteoclast-independent role for N-BP therapy in bone metastasis.
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Affiliation(s)
- Angela C. Hirbe
- Department of Medicine, Division of Molecular Oncology, Washington University School of Medicine, St. Louis, MO, 63110
| | - Anke J. Roelofs
- Bone and Musculoskeletal Research Programme, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD Scotland
| | - Desiree H. Floyd
- Department of Medicine, Division of Molecular Oncology, Washington University School of Medicine, St. Louis, MO, 63110
| | - Hongju Deng
- Department of Medicine, Division of Molecular Oncology, Washington University School of Medicine, St. Louis, MO, 63110
| | - Stephanie N. Becker
- Department of Medicine, Division of Molecular Oncology, Washington University School of Medicine, St. Louis, MO, 63110
| | - Lisa G. Lanigan
- Department of Veterinary Biosciences, College of Veterinary Medicine, Ohio State University, Columbus, OH
| | - Anthony J. Apicelli
- Department of Medicine, Division of Molecular Oncology, Washington University School of Medicine, St. Louis, MO, 63110
| | - Zhiqiang Xu
- Department of Medicine, Division of Molecular Oncology, Washington University School of Medicine, St. Louis, MO, 63110
| | - Julie L. Prior
- Molecular Imaging Center, Department of Radiology, Washington University School of Medicine, St. Louis, MO, 63110
| | - Mark C. Eagleton
- Department of Medicine, Division of Molecular Oncology, Washington University School of Medicine, St. Louis, MO, 63110
| | - David Piwnica-Worms
- Molecular Imaging Center, Department of Radiology, Washington University School of Medicine, St. Louis, MO, 63110
| | - Michael J. Rogers
- Bone and Musculoskeletal Research Programme, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD Scotland
| | - Katherine Weilbaecher
- Department of Medicine, Division of Molecular Oncology, Washington University School of Medicine, St. Louis, MO, 63110
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