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Almuqbil M, Alshaikh FY, Altwaijri W, Baarmah D, Hommady RH, Alshaikh MY, Alammari F, Alhussain M, Almotawa R, Alqarny F, Kashgari A, Alkhodair R, Alkhater JN, Alkhater LN, Alharthi SA, Alsadi MA, AlRumayyan A. Epidemiology and Outcomes of Neurofibromatosis Type 1 (NF-1): Multicenter Tertiary Experience. J Multidiscip Healthc 2024; 17:1303-1314. [PMID: 38533410 PMCID: PMC10964784 DOI: 10.2147/jmdh.s454921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Accepted: 03/13/2024] [Indexed: 03/28/2024] Open
Abstract
Purpose The aim of this manuscript was to assess the epidemiology and clinical features of Neurofibromatosis type 1 (NF-1) based on the newly published revised NF-1 diagnostic criteria and to evaluate complications of NF-1 including neurodevelopmental disorders. Patients and methods A retrospective cross-sectional observational study was conducted in the Ministry of National Guard Health Affairs (MNGHA) healthcare organization branches including four tertiary hospitals and 51 primary health care centers in different regions in Saudi Arabia. This study included all patients diagnosed with NF1 using the revised NIH diagnostic criteria published in 2021 that were registered at the electronic medical records (EMR) from 2015 to 2021. Results A total of 184 patients fulfilled the diagnostic criteria and were included in this study. The median age at diagnosis was 11 years (IQR: 4.00-20.25). The most encountered diagnostic criteria in this study were Café-au-lait macules (85.3%), and (42.9%) were found to have two or more neurofibromas with plexiform neurofibroma being the most common subtype (23.36%), approximately (36.4%) of the patient with optic pathway glioma. Nearby (26.6%) of the patients displayed different type of tumors. Iris Lisch nodules were presented in 36.4% of patients at a median age of 12 years (IQR: 9.0-21.8). Cardiovascular abnormality was encountered in 9.8% of the patients. Around 27.7% of the patients reported headache and 11.4% of the patient suffered from different type of epilepsy. Besides, 10.5% of the patients had intellectual disability, 33.8% suffered from communication disorders, and 4.9% patients had ADHD. Conclusion The results of this study will enable practitioners to adopt a more holistic approach and prioritize numerous attributes, which they can subsequently incorporate into their therapeutic methodologies. Furthermore, the identification of these attributes will facilitate an expeditious and accurate diagnosis. Hence, the implementation of intervention during its nascent phase may result in a more advantageous consequence.
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Affiliation(s)
- Mohammed Almuqbil
- College of Medicine, King Saud Bin Abdulaziz University for Health Sciences (KSAU-HS), Riyadh, Saudi Arabia
- King Abdullah International Medical Research Center (KAIMRC), Ministry of National Guard, Riyadh, Saudi Arabia
- Division of Pediatric Neurology, Department of Pediatrics, King Abdullah Specialist Children’s Hospital (KASCH), National Guard Health Affairs (NGHA), Riyadh, Saudi Arabia
| | | | - Waleed Altwaijri
- College of Medicine, King Saud Bin Abdulaziz University for Health Sciences (KSAU-HS), Riyadh, Saudi Arabia
- King Abdullah International Medical Research Center (KAIMRC), Ministry of National Guard, Riyadh, Saudi Arabia
- Division of Pediatric Neurology, Department of Pediatrics, King Abdullah Specialist Children’s Hospital (KASCH), National Guard Health Affairs (NGHA), Riyadh, Saudi Arabia
| | - Duaa Baarmah
- Department of Pediatrics, King Abdullah Bin Abdulaziz University Hospital, Princess Nourah Bint Abdulrahman University, Riyadh, Saudi Arabia
| | - Raid Harb Hommady
- King Abdullah International Medical Research Center (KAIMRC), Ministry of National Guard, Riyadh, Saudi Arabia
- Division of Pediatric Neurology, Department of Pediatrics, King Abdullah Specialist Children’s Hospital (KASCH), National Guard Health Affairs (NGHA), Riyadh, Saudi Arabia
| | - Maryam Yaseen Alshaikh
- College of Medicine, King Saud Bin Abdulaziz University for Health Sciences (KSAU-HS), Riyadh, Saudi Arabia
| | - Fares Alammari
- College of Medicine, Almaarefa University, Riyadh, Saudi Arabia
| | | | | | - Faris Alqarny
- College of Dentistry, King Saud Bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia
| | - Amna Kashgari
- College of Medicine, King Saud Bin Abdulaziz University for Health Sciences (KSAU-HS), Riyadh, Saudi Arabia
- Department of Radiology, King Abdullah Specialist Children’s Hospital (KASCH), National Guard Health Affairs (NGHA), Riyadh, Saudi Arabia
| | - Rayan Alkhodair
- College of Medicine, King Saud Bin Abdulaziz University for Health Sciences (KSAU-HS), Riyadh, Saudi Arabia
- King Abdullah International Medical Research Center (KAIMRC), Ministry of National Guard, Riyadh, Saudi Arabia
- Division of Dermatology, King Abdulaziz Medical City, Riyadh, Saudi Arabia
| | - Jumanah N Alkhater
- College of Medicine, King Saud Bin Abdulaziz University for Health Sciences (KSAU-HS), Riyadh, Saudi Arabia
| | | | - Sawsan A Alharthi
- Division of Dermatology, King Abdulaziz Medical City, Riyadh, Saudi Arabia
| | - Mada Abdulkarim Alsadi
- Division of Otolaryngology, Head and Neck Surgery, King Abdulaziz University Hospital, Riyadh, Saudi Arabia
| | - Ahmed AlRumayyan
- College of Medicine, King Saud Bin Abdulaziz University for Health Sciences (KSAU-HS), Riyadh, Saudi Arabia
- King Abdullah International Medical Research Center (KAIMRC), Ministry of National Guard, Riyadh, Saudi Arabia
- Division of Pediatric Neurology, Department of Pediatrics, King Abdullah Specialist Children’s Hospital (KASCH), National Guard Health Affairs (NGHA), Riyadh, Saudi Arabia
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Fowlkes JL, Thrailkill KM, Bunn RC. RASopathies: The musculoskeletal consequences and their etiology and pathogenesis. Bone 2021; 152:116060. [PMID: 34144233 PMCID: PMC8316423 DOI: 10.1016/j.bone.2021.116060] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 06/07/2021] [Accepted: 06/10/2021] [Indexed: 01/07/2023]
Abstract
The RASopathies comprise an ever-growing number of clinical syndromes resulting from germline mutations in components of the RAS/MAPK signaling pathway. While multiple organs and tissues may be affected by these mutations, this review will focus on how these mutations specifically impact the musculoskeletal system. Herein, we review the genetics and musculoskeletal phenotypes of these syndromes in humans. We discuss how mutations in the RASopathy syndromes have been studied in translational mouse models. Finally, we discuss how signaling molecules within the RAS/MAPK pathway are involved in normal and abnormal bone biology in the context of osteoblasts, osteoclasts and chondrocytes.
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Affiliation(s)
- John L Fowlkes
- University of Kentucky Barnstable Brown Diabetes Center, Department of Pediatrics, University of Kentucky College of Medicine, Lexington, KY 40536, United States of America.
| | - Kathryn M Thrailkill
- University of Kentucky Barnstable Brown Diabetes Center, Department of Pediatrics, University of Kentucky College of Medicine, Lexington, KY 40536, United States of America
| | - R Clay Bunn
- University of Kentucky Barnstable Brown Diabetes Center, Department of Pediatrics, University of Kentucky College of Medicine, Lexington, KY 40536, United States of America
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Toro G, Santoro C, Ambrosio D, Landi G, Scilipoti M, Moretti A, Paoletta M, Liguori S, Schiavone Panni A, Picariello S, Iolascon G. Natural History of Scoliosis in Children with NF1: An Observation Study. Healthcare (Basel) 2021; 9:healthcare9070881. [PMID: 34356257 PMCID: PMC8303287 DOI: 10.3390/healthcare9070881] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 06/25/2021] [Accepted: 07/09/2021] [Indexed: 02/05/2023] Open
Abstract
(1) Background. Scoliosis is the most common musculoskeletal manifestation of Neurofibromatosis type 1 (NF1), and it might be dystrophic (D) or non-dystrophic (ND) depending on the presence of dysplastic changes of the spine. The aim of our study was to describe the characteristics and natural history of patients with NF1 and scoliosis. (2) Methods. We retrospectively reviewed records from patients with NF1 and scoliosis. Scoliosis was classified as D if at least two dystrophic changes were documented at imaging. (3) Results. Of the 438 patients reviewed, 43 fulfilled inclusion criteria; 17 were classified in D group and 26 in ND. The groups did not differ in age and localization of scoliosis curvature. Surgery was needed more often in D group, but the between-group difference was not significant. Male-to-female ratios of 3:1 and 4:1 were reported in surgically treated NF1 patients with ND and D scoliosis, respectively. (4) Conclusions. Our data suggests independently by the presence of dysplastic changes affecting the spine that males with NF1 are more often affected by scoliosis that requires surgery.
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Affiliation(s)
- Giuseppe Toro
- Department of Medical and Surgical Specialties and Dentistry, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (G.T.); (D.A.); (G.L.); (A.M.); (S.L.); (A.S.P.); (G.I.)
- Department of Clinical Sciences and Translational Medicine, University of Rome Tor Vergata, 00133 Rome, Italy
| | - Claudia Santoro
- Department of Woman, Child and of General and Specialised Surgery, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (C.S.); (M.S.); (S.P.)
- Department of Mental Health, Physical and Preventive Medicine, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy
| | - Daniele Ambrosio
- Department of Medical and Surgical Specialties and Dentistry, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (G.T.); (D.A.); (G.L.); (A.M.); (S.L.); (A.S.P.); (G.I.)
| | - Giovanni Landi
- Department of Medical and Surgical Specialties and Dentistry, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (G.T.); (D.A.); (G.L.); (A.M.); (S.L.); (A.S.P.); (G.I.)
| | - Martina Scilipoti
- Department of Woman, Child and of General and Specialised Surgery, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (C.S.); (M.S.); (S.P.)
| | - Antimo Moretti
- Department of Medical and Surgical Specialties and Dentistry, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (G.T.); (D.A.); (G.L.); (A.M.); (S.L.); (A.S.P.); (G.I.)
| | - Marco Paoletta
- Department of Medical and Surgical Specialties and Dentistry, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (G.T.); (D.A.); (G.L.); (A.M.); (S.L.); (A.S.P.); (G.I.)
- Correspondence:
| | - Sara Liguori
- Department of Medical and Surgical Specialties and Dentistry, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (G.T.); (D.A.); (G.L.); (A.M.); (S.L.); (A.S.P.); (G.I.)
| | - Alfredo Schiavone Panni
- Department of Medical and Surgical Specialties and Dentistry, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (G.T.); (D.A.); (G.L.); (A.M.); (S.L.); (A.S.P.); (G.I.)
| | - Stefania Picariello
- Department of Woman, Child and of General and Specialised Surgery, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (C.S.); (M.S.); (S.P.)
| | - Giovanni Iolascon
- Department of Medical and Surgical Specialties and Dentistry, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy; (G.T.); (D.A.); (G.L.); (A.M.); (S.L.); (A.S.P.); (G.I.)
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Etani Y, Ebina K, Hirao M, Kitaguchi K, Kashii M, Ishimoto T, Nakano T, Okamura G, Miyama A, Takami K, Goshima A, Kanamoto T, Nakata K, Yoshikawa H. Combined effect of teriparatide and an anti-RANKL monoclonal antibody on bone defect regeneration in mice with glucocorticoid-induced osteoporosis. Bone 2020; 139:115525. [PMID: 32645445 DOI: 10.1016/j.bone.2020.115525] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 06/21/2020] [Accepted: 07/02/2020] [Indexed: 01/23/2023]
Abstract
OBJECTIVE The purpose of this study was to examine the effect of single or combination therapy of teriparatide (TPTD) and a monoclonal antibody against the murine receptor activator of nuclear factor κB ligand (anti-RANKL Ab) on cancellous and cortical bone regeneration in a mouse model of glucocorticoid-induced osteoporosis (GIOP). METHODS C57BL/6 J mice (24 weeks of age) were divided into five groups: (1) the SHAM group: sham operation + saline; (2) the prednisolone (PSL) group: PSL + saline; (3) the TPTD group: PSL + TPTD; (4) the Ab group: PSL + anti-RANKL Ab; and (5) the COMB group: PSL + TPTD + anti-RANKL Ab (n = 8 per group). With the exception of the SHAM group, 7.5 mg of PSL was inserted subcutaneously into mice, to generate a mouse model of GIOP. Four weeks after insertion, bone defects with a diameter of 0.9 mm were created to assess bone regeneration on both femoral metaphysis (cancellous bone) and diaphysis (cortical bone). After surgery, therapeutic intervention was continued for 4 weeks. Saline (200 μl) or TPTD (40 μg/kg) was injected subcutaneously five times per week, whereas the anti-RANKL Ab (5 mg/kg) was injected subcutaneously once on the day after surgery. Subsequently, the following analyses were performed: microstructural assessment of bone regeneration and bone mineral density (BMD) measurement via micro-computed tomography, and histological, histomorphometrical, and biomechanical analyses with nanoindentation. RESULTS The COMB group showed the highest lumbar spine BMD increase (vs. the PSL, TPTD, and Ab groups). The volume of regenerated cancellous bone at the bone defect site was higher in the COMB group compared with the PSL, TPTD, and Ab group. The volume of the regenerated cortical bone was significantly higher in the COMB group compared with the PSL group, and its hardness was significantly higher in the COMB group compared with the PSL and TPTD groups. CONCLUSION In a mouse model of glucocorticoid-induced osteoporosis, the combination therapy of TPTD plus the anti-RANKL Ab increased bone mineral density in the lumbar spine and regenerated cancellous bone volume compared with single administration of each agent, and also increased regenerated cortical bone strength compared with single administration of TPTD.
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Affiliation(s)
- Yuki Etani
- Department of Orthopaedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Kosuke Ebina
- Department of Musculoskeletal Regenerative Medicine, Osaka University Graduate School of Medicine, 2-2 Yamada-oka, Suita, Osaka 565-0871, Japan.
| | - Makoto Hirao
- Department of Orthopaedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Kazuma Kitaguchi
- Department of Orthopaedic Surgery, Toyonaka Municipal Hospital, 4-14-1 Shibaharacho, Toyonaka, Osaka 560-8565, Japan
| | - Masafumi Kashii
- Department of Orthopaedic Surgery, Toyonaka Municipal Hospital, 4-14-1 Shibaharacho, Toyonaka, Osaka 560-8565, Japan
| | - Takuya Ishimoto
- Division of Materials and Manufacturing Science, Osaka University Graduate School of Engineering, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Takayoshi Nakano
- Division of Materials and Manufacturing Science, Osaka University Graduate School of Engineering, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Gensuke Okamura
- Department of Orthopaedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Akira Miyama
- Department of Orthopaedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Kenji Takami
- Department of Orthopaedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Atsushi Goshima
- Department of Orthopaedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Takashi Kanamoto
- Department of Health and Sport Sciences, Osaka University Graduate School of Medicine, 2-2 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Ken Nakata
- Department of Health and Sport Sciences, Osaka University Graduate School of Medicine, 2-2 Yamada-oka, Suita, Osaka 565-0871, Japan
| | - Hideki Yoshikawa
- Department of Orthopaedic Surgery, Toyonaka Municipal Hospital, 4-14-1 Shibaharacho, Toyonaka, Osaka 560-8565, Japan
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5
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Kitaguchi K, Kashii M, Ebina K, Kaito T, Okada R, Makino T, Etani Y, Ishimoto T, Nakano T, Yoshikawa H. The combined effects of teriparatide and anti-RANKL monoclonal antibody on bone defect regeneration in ovariectomized mice. Bone 2020; 130:115077. [PMID: 31622773 DOI: 10.1016/j.bone.2019.115077] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 09/23/2019] [Accepted: 09/23/2019] [Indexed: 01/01/2023]
Abstract
OBJECTIVE The purpose of this study was to investigate the combined effects of teriparatide (TPTD) and anti-murine receptor activator of nuclear factor-κB ligand monoclonal antibody (anti-RANKL Ab) on both cancellous and cortical bone healing in ovariectomized mice. METHODS Thirteen-week-old mice were divided into the sham-operated group (n=11) or the ovariectomized group (n=44). At 1 month post-operation, all mice underwent bone defect surgery on the left femoral metaphysis (cancellous bone healing model) and right femoral mid-diaphysis (cortical bone healing model). After creating the bone defects, all ovariectomized mice were assigned to one of four groups to receive 1) saline (5 times a week; CNT group), 2) TPTD (40μg/kg 5 times a week; TPTD group), 3) anti-RANKL Ab (5mg/kg once; Ab group), or 4) a combination of TPTD and anti-RANKL Ab (COMB group). The following analyses were performed: Time-course microstructural analysis of healing in both cancellous and cortical bone in the bone defect, measuring the volumetric bone mineral density and the cortical bone thickness of the tibia as a representative of whole body bone with the use of micro-computed tomography, and histological analysis. RESULTS Regeneration of cancellous bone volume in the COMB group was the highest among the four groups, and combined treatment accelerated the formation of medullary callus during the early phase of bone regeneration. On the other hand, there were no significant differences in the regeneration of cortical bone volume during the early phase of bone regeneration among the four groups. Furthermore, lamellar bone was not well identified in the all four groups. Volumetric bone mineral density in the tibia in the COMB group was significantly higher compared with that in the CNT and TPTD groups and tended to be higher compared with that in the Ab group. The mean values of cortical bone thickness in the TPTD and COMB groups were significantly higher than that in the CNT group. CONCLUSION In a mouse model of postmenopausal osteoporosis, combination therapy of TPTD and anti-RANKL Ab accelerates regeneration of cancellous bone more effectively than either agent alone during the early phase of bone regeneration.
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Affiliation(s)
- Kazuma Kitaguchi
- Department of Orthopedic Surgery, Toyonaka Municipal Hospital, 4-14-1 Shibaharamachi, Toyonaka, 560-8565, Japan; Department of Orthopedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan.
| | - Masafumi Kashii
- Department of Orthopedic Surgery, Toyonaka Municipal Hospital, 4-14-1 Shibaharamachi, Toyonaka, 560-8565, Japan; Department of Orthopedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan.
| | - Kosuke Ebina
- Department of Orthopedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan.
| | - Takashi Kaito
- Department of Orthopedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan.
| | - Rintaro Okada
- Department of Orthopedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan.
| | - Takahiro Makino
- Department of Orthopedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan.
| | - Yuki Etani
- Department of Orthopedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan.
| | - Takuya Ishimoto
- Division of Materials and Manufacturing Science, Graduate School Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka, 565-0871, Japan.
| | - Takayoshi Nakano
- Division of Materials and Manufacturing Science, Graduate School Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka, 565-0871, Japan.
| | - Hideki Yoshikawa
- Department of Orthopedic Surgery, Toyonaka Municipal Hospital, 4-14-1 Shibaharamachi, Toyonaka, 560-8565, Japan; Department of Orthopedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan.
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Yang S, Liu H, Zhu L, Li X, Liu D, Song X, Yokota H, Zhang P. Ankle loading ameliorates bone loss from breast cancer-associated bone metastasis. FASEB J 2019; 33:10742-10752. [PMID: 31266364 PMCID: PMC8793785 DOI: 10.1096/fj.201900306rr] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Accepted: 06/04/2019] [Indexed: 02/15/2024]
Abstract
Breast cancer is a serious health problem that preferentially metastasizes to bone. We have previously shown that bone loss can be prevented by mechanical loading, but the efficacy of ankle loading for metastasis-linked bone loss has not been investigated. This study showed that body weight was decreased after inoculation of tumor cells, but ankle loading restored a rapid weight loss. The nonloading group exhibited a decrease in bone volume/tissue volume (BV/TV), trabecular thickness, and trabecular number (all P < 0.01) as well as an increase in trabecular separation (P < 0.001). However, ankle loading improved those changes (all P < 0.05). Furthermore, although the nonloading group increased the tumor bearing as well as expression of IL-8 and matrix metalloproteinase 9, ankle loading decreased them. Induction of tumor in the bone elevated the osteoclast number (P < 0.05) as well as the levels of nuclear factor of activated T-cells cytoplasmic 1, NF-κB ligand, cathepsin K, and serum tartrate-resistant acid phosphatase type 5b, but ankle loading reduced osteoclast activity and those levels (all P < 0.05). Tumor bearing was positively correlated with the osteoclast number (P < 0.01) and negatively correlated with BV/TV and the osteoblast number (both P < 0.01). Collectively, these findings demonstrate that ankle loading suppresses tumor growth and osteolysis by inhibiting bone resorption and enhancing bone formation.-Yang, S., Liu, H., Zhu, L., Li, X., Liu, D., Song, X., Yokota, H., Zhang, P. Ankle loading ameliorates bone loss from breast cancer-associated bone metastasis.
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Affiliation(s)
- Shuang Yang
- Department of Anatomy and HistologySchool of Basic Medical SciencesTianjin Medical UniversityTianjinChina
- Key Laboratory of Hormones and Development, Ministry of HealthTianjin Key Laboratory of Metabolic DiseasesTianjin Medical UniversityTianjinChina
| | - Hong Liu
- Key Laboratory of Cancer Prevention and Therapy, Ministry of EducationTianjin Medical UniversityTianjinChina
- Department of Breast SurgeryTianjin Medical UniversityCancer Institute and HospitalTianjinChina
- Key Laboratory of Cancer Prevention and TherapyTianjinChina
- Tianjin's Clinical Research Center for CancerTianjinChina
| | - Lei Zhu
- Department of Molecular Imaging and Nuclear MedicineNational Clinical Research Center for CancerTianjin Medical UniversityCancer Institute and HospitalTianjinChina
- Key Laboratory of Cancer Prevention and TherapyTianjinChina
| | - Xinle Li
- Department of Anatomy and HistologySchool of Basic Medical SciencesTianjin Medical UniversityTianjinChina
- Key Laboratory of Hormones and Development, Ministry of HealthTianjin Key Laboratory of Metabolic DiseasesTianjin Medical UniversityTianjinChina
| | - Daquan Liu
- Department of Anatomy and HistologySchool of Basic Medical SciencesTianjin Medical UniversityTianjinChina
- Key Laboratory of Hormones and Development, Ministry of HealthTianjin Key Laboratory of Metabolic DiseasesTianjin Medical UniversityTianjinChina
| | - Xiaomeng Song
- Department of Anatomy and HistologySchool of Basic Medical SciencesTianjin Medical UniversityTianjinChina
| | - Hiroki Yokota
- Department of Biomedical EngineeringIndiana University-Purdue University IndianapolisIndianapolisIndianaUSA
| | - Ping Zhang
- Department of Anatomy and HistologySchool of Basic Medical SciencesTianjin Medical UniversityTianjinChina
- Key Laboratory of Hormones and Development, Ministry of HealthTianjin Key Laboratory of Metabolic DiseasesTianjin Medical UniversityTianjinChina
- Tianjin Key Laboratory of Spine and Spinal CordTianjin Medical UniversityTianjinChina
- Tianjin's Clinical Research Center for CancerTianjinChina
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7
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Brekelmans C, Hollants S, De Groote C, Sohier N, Maréchal M, Geris L, Luyten FP, Ginckels L, Sciot R, de Ravel T, De Smet L, Lammens J, Legius E, Brems H. Neurofibromatosis type 1-related pseudarthrosis: Beyond the pseudarthrosis site. Hum Mutat 2019; 40:1760-1767. [PMID: 31066482 DOI: 10.1002/humu.23783] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Revised: 05/03/2019] [Accepted: 05/04/2019] [Indexed: 12/23/2022]
Abstract
Neurofibromatosis type 1 (NF1) is an autosomal dominant disorder affecting approximately 1 in 2,000 newborns. Up to 5% of NF1 patients suffer from pseudarthrosis of a long bone (NF1-PA). Current treatments are often unsatisfactory, potentially leading to amputation. To gain more insight into the pathogenesis we cultured cells from PA tissue and normal-appearing periosteum of the affected bone for NF1 mutation analysis. PA cells were available from 13 individuals with NF1. Biallelic NF1 inactivation was identified in all investigated PA cells obtained during the first surgery. Three of five cases sampled during a later intervention showed biallelic NF1 inactivation. Also, in three individuals, we examined periosteum-derived cells from normal-appearing periosteum proximal and distal to the PA. We identified the same biallelic NF1 inactivation in the periosteal cells outside the PA region. These results indicate that NF1 inactivation is required but not sufficient for the development of NF1-PA. We observed that late-onset NF1-PA occurs and is not always preceded by congenital bowing. Furthermore, the failure to identify biallelic inactivation in two of five later interventions and one reintervention with a known somatic mutation indicates that NF1-PA can persist after the removal of most NF1 negative cells.
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Affiliation(s)
- Carlijn Brekelmans
- Department of Human Genetics, KU Leuven-University of Leuven, Leuven, Belgium
| | - Silke Hollants
- Clinical Department of Human Genetics, KU Leuven-University of Leuven, University Hospitals Leuven, Leuven, Belgium
| | - Caroline De Groote
- Clinical Department of Human Genetics, KU Leuven-University of Leuven, University Hospitals Leuven, Leuven, Belgium
| | - Natalie Sohier
- Clinical Department of Human Genetics, KU Leuven-University of Leuven, University Hospitals Leuven, Leuven, Belgium
| | - Marina Maréchal
- Department of Development and Regeneration, Prometheus LRD Division of Skeletal Tissue Engineering, KU Leuven-University of Leuven, Leuven, Belgium
| | - Liesbet Geris
- Department of Mechanical Engineering, Prometheus LRD Division of Skeletal Tissue Engineering, KU Leuven-University of Leuven, Leuven, Belgium.,GIGA In Silico Medicine, University of Liège, Liège, Belgium
| | - Frank P Luyten
- Department of Development and Regeneration, Prometheus LRD Division of Skeletal Tissue Engineering, KU Leuven-University of Leuven, Leuven, Belgium.,Department of Rheumatology, KU Leuven-University Hospitals Leuven, Leuven, Belgium
| | - Lieve Ginckels
- Department of Orthopaedic Surgery, KU Leuven-University of Leuven, University Hospitals Leuven, Leuven, Belgium
| | - Raf Sciot
- Department of Imaging and Pathology, KU Leuven-University of Leuven, Leuven, Belgium.,Department of Pathology, KU Leuven-University of Leuven, University Hospitals Leuven, Leuven, Belgium
| | - Thomy de Ravel
- Department of Human Genetics, KU Leuven-University of Leuven, Leuven, Belgium.,Clinical Department of Human Genetics, KU Leuven-University of Leuven, University Hospitals Leuven, Leuven, Belgium
| | - Luc De Smet
- Department of Orthopaedic Surgery, KU Leuven-University of Leuven, University Hospitals Leuven, Leuven, Belgium.,Department of Development and Regeneration, KU Leuven-University of Leuven, Leuven, Belgium
| | - Johan Lammens
- Department of Development and Regeneration, Prometheus LRD Division of Skeletal Tissue Engineering, KU Leuven-University of Leuven, Leuven, Belgium.,Department of Orthopaedic Surgery, KU Leuven-University of Leuven, University Hospitals Leuven, Leuven, Belgium
| | - Eric Legius
- Department of Human Genetics, KU Leuven-University of Leuven, Leuven, Belgium.,Clinical Department of Human Genetics, KU Leuven-University of Leuven, University Hospitals Leuven, Leuven, Belgium
| | - Hilde Brems
- Department of Human Genetics, KU Leuven-University of Leuven, Leuven, Belgium.,Clinical Department of Human Genetics, KU Leuven-University of Leuven, University Hospitals Leuven, Leuven, Belgium
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Tajan M, Paccoud R, Branka S, Edouard T, Yart A. The RASopathy Family: Consequences of Germline Activation of the RAS/MAPK Pathway. Endocr Rev 2018; 39:676-700. [PMID: 29924299 DOI: 10.1210/er.2017-00232] [Citation(s) in RCA: 135] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Accepted: 06/13/2018] [Indexed: 12/13/2022]
Abstract
Noonan syndrome [NS; Mendelian Inheritance in Men (MIM) #163950] and related syndromes [Noonan syndrome with multiple lentigines (formerly called LEOPARD syndrome; MIM #151100), Noonan-like syndrome with loose anagen hair (MIM #607721), Costello syndrome (MIM #218040), cardio-facio-cutaneous syndrome (MIM #115150), type I neurofibromatosis (MIM #162200), and Legius syndrome (MIM #611431)] are a group of related genetic disorders associated with distinctive facial features, cardiopathies, growth and skeletal abnormalities, developmental delay/mental retardation, and tumor predisposition. NS was clinically described more than 50 years ago, and disease genes have been identified throughout the last 3 decades, providing a molecular basis to better understand their physiopathology and identify targets for therapeutic strategies. Most of these genes encode proteins belonging to or regulating the so-called RAS/MAPK signaling pathway, so these syndromes have been gathered under the name RASopathies. In this review, we provide a clinical overview of RASopathies and an update on their genetics. We then focus on the functional and pathophysiological effects of RASopathy-causing mutations and discuss therapeutic perspectives and future directions.
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Affiliation(s)
- Mylène Tajan
- INSERM UMR 1048, Institute of Cardiovascular and Metabolic Diseases (I2MC), University of Toulouse Paul Sabatier, Toulouse, France
| | - Romain Paccoud
- INSERM UMR 1048, Institute of Cardiovascular and Metabolic Diseases (I2MC), University of Toulouse Paul Sabatier, Toulouse, France
| | - Sophie Branka
- INSERM UMR 1048, Institute of Cardiovascular and Metabolic Diseases (I2MC), University of Toulouse Paul Sabatier, Toulouse, France
| | - Thomas Edouard
- Endocrine, Bone Diseases, and Genetics Unit, Children's Hospital, Toulouse University Hospital, Toulouse, France
| | - Armelle Yart
- INSERM UMR 1048, Institute of Cardiovascular and Metabolic Diseases (I2MC), University of Toulouse Paul Sabatier, Toulouse, France
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9
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Apolipoprotein E plays crucial roles in maintaining bone mass by promoting osteoblast differentiation via ERK1/2 pathway and by suppressing osteoclast differentiation via c-Fos, NFATc1, and NF-κB pathway. Biochem Biophys Res Commun 2018; 503:644-650. [DOI: 10.1016/j.bbrc.2018.06.055] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 06/11/2018] [Indexed: 12/27/2022]
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10
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She D, Zhang K. Fibrodysplasia ossificans progressiva in China. Bone 2018; 109:101-103. [PMID: 29175272 DOI: 10.1016/j.bone.2017.11.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 11/19/2017] [Accepted: 11/20/2017] [Indexed: 11/23/2022]
Abstract
Fibrodysplasia ossificans progressiva (FOP) is an ultra-rare and devastating disorder characterized by cumulative episodes of progressive heterotopic ossification. It is estimated that there exist 600-700 patients in Mainland China. Nevertheless, due to the rarity, many FOP patients were initially misdiagnosed. Until now fewer than 150 patients have been identified in Mainland China. This review summarizes the epidemiology and clinical features of FOP patients, the progress of clinical and basic research in China, and the future of FOP care in China.
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Affiliation(s)
- Dunmin She
- Department of Endocrinology and Metabolism, Tongji Hospital, Tongji University School of Medicine, Shanghai, People's Republic of China
| | - Keqin Zhang
- Department of Endocrinology and Metabolism, Tongji Hospital, Tongji University School of Medicine, Shanghai, People's Republic of China.
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11
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Shih YT, Hsueh YP. The involvement of endoplasmic reticulum formation and protein synthesis efficiency in VCP- and ATL1-related neurological disorders. J Biomed Sci 2018; 25:2. [PMID: 29310658 PMCID: PMC5757295 DOI: 10.1186/s12929-017-0403-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Accepted: 12/26/2017] [Indexed: 12/13/2022] Open
Abstract
The endoplasmic reticulum (ER) is the biggest organelle in cells and is involved in versatile cellular processes. Formation and maintenance of ER morphology are regulated by a series of proteins controlling membrane fusion and curvature. At least six different ER morphology regulators have been demonstrated to be involved in neurological disorders-including Valosin-containing protein (VCP), Atlastin-1 (ATL1), Spastin (SPAST), Reticulon 2 (RTN2), Receptor expression enhancing protein 1 (REEP1) and RAB10-suggesting a critical role of ER formation in neuronal activity and function. Among these genes, mutations in VCP gene involve in inclusion body myopathy with Paget disease of bone and frontotemporal dementia (IBMPFD), familial amyotrophic lateral sclerosis (ALS), autism spectrum disorders (ASD), and hereditary spastic paraplegia (HSP). ATL1 is also one of causative genes of HSP. RAB10 is associated with Parkinson's disease (PD). A recent study showed that VCP and ATL1 work together to regulate dendritic spine formation by controlling ER formation and consequent protein synthesis efficiency. RAB10 shares the same function with VCP and ATL1 to control ER formation and protein synthesis efficiency but acts independently. Increased protein synthesis by adding extra leucine to cultured neurons ameliorated dendritic spine deficits caused by VCP and ATL1 deficiencies, strengthening the significance of protein synthesis in VCP- and ATL1-regulated dendritic spine formation. These findings provide new insight into the roles of ER and protein synthesis in controlling dendritic spine formation and suggest a potential etiology of neurodegenerative disorders caused by mutations in VCP, ATL1 and other genes encoding proteins regulating ER formation and morphogenesis.
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Affiliation(s)
- Yu-Tzu Shih
- Institute of Molecular Biology, Academia Sinica, 128, Academia Rd., Sec. 2, Taipei, 11529, Taiwan
| | - Yi-Ping Hsueh
- Institute of Molecular Biology, Academia Sinica, 128, Academia Rd., Sec. 2, Taipei, 11529, Taiwan.
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12
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Kitaguchi K, Kashii M, Ebina K, Kaito T, Okada R, Makino T, Noguchi T, Ishimoto T, Nakano T, Yoshikawa H. Effects of single or combination therapy of teriparatide and anti-RANKL monoclonal antibody on bone defect regeneration in mice. Bone 2018; 106:1-10. [PMID: 28978416 DOI: 10.1016/j.bone.2017.09.021] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Revised: 09/15/2017] [Accepted: 09/30/2017] [Indexed: 01/24/2023]
Abstract
OBJECTIVE The purpose of this study is to investigate the effects of a single or combination therapy of teriparatide (TPTD) and anti-RANKL Ab (anti-murine receptor activator of nuclear factor κB ligand monoclonal antibody) on the regeneration of both cancellous and cortical bone. METHODS Nine-week-old mice underwent bone defect surgery on the left femoral metaphysis (cancellous-bone healing model) and right femoral mid-diaphysis (cortical-bone healing model). After surgery, the mice were assigned to 1 of 4 groups to receive 1) saline (5 times a week; CNT group), 2) TPTD (40μg/kg 5 times a week; TPTD group), 3) anti-RANKL Ab (5mg/kg once; Ab group), or 4) a combination of TPTD and anti-RANKL Ab (COMB group). The following analyses were performed: Time-course microstructural analysis of healing in both cancellous and cortical bone in the bone defect, the volumetric bone mineral density of the tibia with micro-computed tomography, histological, histomorphometrical, and biomechanical analysis of regenerated bone. RESULTS Regeneration of cancellous bone volume in the COMB group was the highest among the 4 groups, and this combined administration prompted medullary callus formation in the early phase of bone regeneration. On the other hand, regeneration of cortical bone volume in the COMB group was significantly higher than in the Ab group and was almost same as in the TPTD group. Histological analysis showed remaining woven bones, cartilage matrix, and immature lamellar bone in the COMB and Ab groups. However, biomechanical analysis showed that hardness and Young's modulus of regenerated cortical bone in the COMB group was not lower than in both the CNT and TPTD groups. Volumetric bone mineral density in the tibia was significantly increased in the COMB group compared with the other 3 groups. CONCLUSION In the early phase of bone regeneration, the combination of TPTD and anti-RANKL Ab accelerates regeneration of cancellous bone in bone defects and increases cancellous bone mass in the tibia more effectively than either agent does individually, but these additive effects are not observed in the regeneration of cortical bone.
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Affiliation(s)
- Kazuma Kitaguchi
- Department of Orthopedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Masafumi Kashii
- Department of Orthopedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Kosuke Ebina
- Department of Orthopedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Takashi Kaito
- Department of Orthopedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Rintaro Okada
- Department of Orthopedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Takahiro Makino
- Department of Orthopedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Takaaki Noguchi
- Department of Orthopedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Takuya Ishimoto
- Division of Materials and Manufacturing Science, Graduate School Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Takayoshi Nakano
- Division of Materials and Manufacturing Science, Graduate School Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Hideki Yoshikawa
- Department of Orthopedic Surgery, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan
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Abstract
The RAS/MAPK signaling pathway plays key roles in development, cell survival and proliferation, as well as in cancer pathogenesis. Molecular genetic studies have identified a group of developmental syndromes, the RASopathies, caused by germ line mutations in this pathway. The syndromes included within this classification are neurofibromatosis type 1 (NF1), Noonan syndrome (NS), Noonan syndrome with multiple lentigines (NS-ML, formerly known as LEOPARD syndrome), Costello syndrome (CS), cardio-facio-cutaneous syndrome (CFC), Legius syndrome (LS, NF1-like syndrome), capillary malformation-arteriovenous malformation syndrome (CM-AVM), and hereditary gingival fibromatosis (HGF) type 1. Although these syndromes present specific molecular alterations, they are characterized by a large spectrum of functional and morphological abnormalities, which include heart defects, short stature, neurocognitive impairment, craniofacial malformations, and, in some cases, cancer predisposition. The development of genetically modified animals, such as mice (Mus musculus), flies (Drosophila melanogaster), and zebrafish (Danio rerio), has been instrumental in elucidating the molecular and cellular bases of these syndromes. Moreover, these models can also be used to determine tumor predisposition, the impact of different genetic backgrounds on the variable phenotypes found among the patients and to evaluate preventative and therapeutic strategies. Here, we review a wide range of genetically modified mouse models used in the study of RASopathies and the potential application of novel technologies, which hopefully will help us resolve open questions in the field.
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14
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Jindal GA, Goyal Y, Burdine RD, Rauen KA, Shvartsman SY. RASopathies: unraveling mechanisms with animal models. Dis Model Mech 2016. [PMID: 26203125 PMCID: PMC4527292 DOI: 10.1242/dmm.020339] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
RASopathies are developmental disorders caused by germline mutations in the Ras-MAPK pathway, and are characterized by a broad spectrum of functional and morphological abnormalities. The high incidence of these disorders (∼1/1000 births) motivates the development of systematic approaches for their efficient diagnosis and potential treatment. Recent advances in genome sequencing have greatly facilitated the genotyping and discovery of mutations in affected individuals, but establishing the causal relationships between molecules and disease phenotypes is non-trivial and presents both technical and conceptual challenges. Here, we discuss how these challenges could be addressed using genetically modified model organisms that have been instrumental in delineating the Ras-MAPK pathway and its roles during development. Focusing on studies in mice, zebrafish and Drosophila, we provide an up-to-date review of animal models of RASopathies at the molecular and functional level. We also discuss how increasingly sophisticated techniques of genetic engineering can be used to rigorously connect changes in specific components of the Ras-MAPK pathway with observed functional and morphological phenotypes. Establishing these connections is essential for advancing our understanding of RASopathies and for devising rational strategies for their management and treatment. Summary: Developmental disorders caused by germline mutations in the Ras-MAPK pathway are called RASopathies. Studies with animal models, including mice, zebrafish and Drosophila, continue to enhance our understanding of these diseases.
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Affiliation(s)
- Granton A Jindal
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08544, USA Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA
| | - Yogesh Goyal
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08544, USA Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA
| | - Rebecca D Burdine
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
| | - Katherine A Rauen
- Department of Pediatrics, MIND Institute, Division of Genomic Medicine, University of California, Davis, Sacramento, CA 95817, USA
| | - Stanislav Y Shvartsman
- Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ 08544, USA Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ 08544, USA Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
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15
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Bakker AC, La Rosa S, Sherman LS, Knight P, Lee H, Pancza P, Nievo M. Neurofibromatosis as a gateway to better treatment for a variety of malignancies. Prog Neurobiol 2016; 152:149-165. [PMID: 26854064 DOI: 10.1016/j.pneurobio.2016.01.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Revised: 01/25/2016] [Accepted: 01/25/2016] [Indexed: 12/23/2022]
Abstract
The neurofibromatoses (NF) are a group of rare genetic disorders that can affect all races equally at an incidence from 1:3000 (NF1) to a log unit lower for NF2 and schwannomatosis. Since the research community is reporting an increasing number of malignant cancers that carry mutations in the NF genes, the general interest of both the research and pharma community is increasing and the authors saw an opportunity to present a novel, fresh approach to drug discovery in NF. The aim of the paper is to challenge the current drug discovery approach to NF, whereby existing targeted therapies that are either in the clinic or on the market for other disease indications are repurposed for NF. We offer a suggestion for an alternative drug discovery approach. In the new approach, selective and tolerable targeted therapies would be developed for NF and later expanded to patients with more complex diseases such as malignant cancer in which the NF downstream pathways are deregulated. The Children's Tumor Foundation, together with some other major NF funders, is playing a key role in funding critical initiatives that will accelerate the development of better targeted therapies for NF patients, while these novel, innovative treatments could potentially be beneficial to molecularly characterized cancer patients in which NF mutations have been identified.
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Affiliation(s)
- Annette C Bakker
- Children's Tumor Foundation, 120, Wall Street, 16th Floor, New York 10005, United States
| | - Salvatore La Rosa
- Children's Tumor Foundation, 120, Wall Street, 16th Floor, New York 10005, United States
| | - Larry S Sherman
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health & Science University, 505 NW 185th Avenue, Beaverton, OR 97006, United States
| | - Pamela Knight
- Children's Tumor Foundation, 120, Wall Street, 16th Floor, New York 10005, United States
| | - Hyerim Lee
- Children's Tumor Foundation, 120, Wall Street, 16th Floor, New York 10005, United States
| | - Patrice Pancza
- Children's Tumor Foundation, 120, Wall Street, 16th Floor, New York 10005, United States
| | - Marco Nievo
- Children's Tumor Foundation, 120, Wall Street, 16th Floor, New York 10005, United States.
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16
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Rhodes SD, Zhang W, Yang D, Yang H, Chen S, Wu X, Li X, Yang X, Mohammad KS, Guise TA, Bergner AL, Stevenson DA, Yang FC. Dystrophic spinal deformities in a neurofibromatosis type 1 murine model. PLoS One 2015; 10:e0119093. [PMID: 25786243 PMCID: PMC4364663 DOI: 10.1371/journal.pone.0119093] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Accepted: 01/16/2015] [Indexed: 12/28/2022] Open
Abstract
Despite the high prevalence and significant morbidity of spinal anomalies in neurofibromatosis type 1 (NF1), the pathogenesis of these defects remains largely unknown. Here, we present two murine models: Nf1flox/−;PeriCre and Nf1flox/−;Col.2.3Cre mice, which recapitulate spinal deformities seen in the human disease. Dynamic histomorphometry and microtomographic studies show recalcitrant bone remodeling and distorted bone microarchitecture within the vertebral spine of Nf1flox/−;PeriCre and Nf1flox/−;Col2.3Cre mice, with analogous histological features present in a human patient with dystrophic scoliosis. Intriguingly, 36–60% of Nf1flox/−;PeriCre and Nf1flox/−;Col2.3Cre mice exhibit segmental vertebral fusion anomalies with boney obliteration of the intervertebral disc (IVD). While analogous findings have not yet been reported in the NF1 patient population, we herein present two case reports of IVD defects and interarticular vertebral fusion in patients with NF1. Collectively, these data provide novel insights regarding the pathophysiology of dystrophic spinal anomalies in NF1, and provide impetus for future radiographic analyses of larger patient cohorts to determine whether IVD and vertebral fusion defects may have been previously overlooked or underreported in the NF1 patient population.
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Affiliation(s)
- Steven D. Rhodes
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Wei Zhang
- Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Hebei Medical University, The Third Hospital, Shijiazhuang, China
| | - Dalong Yang
- Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Hebei Medical University, The Third Hospital, Shijiazhuang, China
| | - Hao Yang
- Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Shi Chen
- Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Xiaohua Wu
- Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Xiaohong Li
- Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Xianlin Yang
- Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Khalid S. Mohammad
- Department of Endocrinology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Theresa A. Guise
- Department of Endocrinology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Amanda L. Bergner
- Department of Neurology, Johns Hopkins Hospital, Baltimore, Maryland, United States of America
| | - David A. Stevenson
- Division of Medical Genetics, Department of Pediatrics, Stanford University, Stanford, California, United States of America
| | - Feng-Chun Yang
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- * E-mail:
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18
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Rhodes SD, Wu X, He Y, Chen S, Yang H, Staser KW, Wang J, Zhang P, Jiang C, Yokota H, Dong R, Peng X, Yang X, Murthy S, Azhar M, Mohammad KS, Xu M, Guise TA, Yang FC. Hyperactive transforming growth factor-β1 signaling potentiates skeletal defects in a neurofibromatosis type 1 mouse model. J Bone Miner Res 2013; 28:2476-89. [PMID: 23703870 PMCID: PMC6774615 DOI: 10.1002/jbmr.1992] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2013] [Revised: 04/29/2013] [Accepted: 05/10/2013] [Indexed: 01/04/2023]
Abstract
Dysregulated transforming growth factor beta (TGF-β) signaling is associated with a spectrum of osseous defects as seen in Loeys-Dietz syndrome, Marfan syndrome, and Camurati-Engelmann disease. Intriguingly, neurofibromatosis type 1 (NF1) patients exhibit many of these characteristic skeletal features, including kyphoscoliosis, osteoporosis, tibial dysplasia, and pseudarthrosis; however, the molecular mechanisms mediating these phenotypes remain unclear. Here, we provide genetic and pharmacologic evidence that hyperactive TGF-β1 signaling pivotally underpins osseous defects in Nf1(flox/-) ;Col2.3Cre mice, a model which closely recapitulates the skeletal abnormalities found in the human disease. Compared to controls, we show that serum TGF-β1 levels are fivefold to sixfold increased both in Nf1(flox/-) ;Col2.3Cre mice and in a cohort of NF1 patients. Nf1-deficient osteoblasts, the principal source of TGF-β1 in bone, overexpress TGF-β1 in a gene dosage-dependent fashion. Moreover, Nf1-deficient osteoblasts and osteoclasts are hyperresponsive to TGF-β1 stimulation, potentiating osteoclast bone resorptive activity while inhibiting osteoblast differentiation. These cellular phenotypes are further accompanied by p21-Ras-dependent hyperactivation of the canonical TGF-β1-Smad pathway. Reexpression of the human, full-length neurofibromin guanosine triphosphatase (GTPase)-activating protein (GAP)-related domain (NF1 GRD) in primary Nf1-deficient osteoblast progenitors, attenuated TGF-β1 expression levels and reduced Smad phosphorylation in response to TGF-β1 stimulation. As an in vivo proof of principle, we demonstrate that administration of the TGF-β receptor 1 (TβRI) kinase inhibitor, SD-208, can rescue bone mass deficits and prevent tibial fracture nonunion in Nf1(flox/-) ;Col2.3Cre mice. In sum, these data demonstrate a pivotal role for hyperactive TGF-β1 signaling in the pathogenesis of NF1-associated osteoporosis and pseudarthrosis, thus implicating the TGF-β signaling pathway as a potential therapeutic target in the treatment of NF1 osseous defects that are refractory to current therapies.
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Affiliation(s)
- Steven D Rhodes
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, IN, USA; Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indiana University School of Medicine, Indianapolis, IN, USA
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Approaches to treating NF1 tibial pseudarthrosis: consensus from the Children's Tumor Foundation NF1 Bone Abnormalities Consortium. J Pediatr Orthop 2013; 33:269-75. [PMID: 23482262 DOI: 10.1097/bpo.0b013e31828121b8] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND Neurofibromatosis 1 (NF1) is an autosomal dominant disorder with various skeletal abnormalities occurring as part of a complex phenotype. Tibial dysplasia, which typically presents as anterolateral bowing of the leg with subsequent fracture and nonunion (pseudarthrosis), is a serious but infrequent osseous manifestation of NF1. Over the past several years, results from clinical and experimental studies have advanced our knowledge of the role of NF1 in bone. On the basis of current knowledge, we propose a number of concepts to consider as a theoretical approach to the optimal management of tibial pseudarthrosis. METHODS A literature review for both clinical treatment and preclinical models for tibial dysplasia in NF1 was performed. Concepts were discussed and developed by experts who participated in the Children's Tumor Foundation sponsored International Bone Abnormalities Consortium meeting in 2011. RESULTS Concepts for a theoretical approach to treating tibial pseudarthrosis include: bone fixation appropriate to achieve stability in any given case; debridement of the "fibrous pseudarthrosis tissue" between the bone segments associated with the pseudarthrosis; creating a healthy vascular bed for bone repair; promoting osteogenesis; controlling overactive bone resorption (catabolism); prevention of recurrence of the "fibrous pseudarthrosis tissue"; and achievement of long-term bone health to prevent recurrence. CONCLUSIONS Clinical trials are needed to assess effectiveness of the wide variation of surgical and pharmacologic approaches currently in practice for the treatment of tibial pseudarthrosis in NF1. LEVEL OF EVIDENCE Level V, expert opinion.
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Gutmann DH, Blakeley JO, Korf BR, Packer RJ. Optimizing biologically targeted clinical trials for neurofibromatosis. Expert Opin Investig Drugs 2013; 22:443-62. [PMID: 23425047 PMCID: PMC4009992 DOI: 10.1517/13543784.2013.772979] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
INTRODUCTION The neurofibromatoses (neurofibromatosis type 1, NF1 and neurofibromatosis type 2, NF2) comprise the most common inherited conditions in which affected children and adults develop tumors of the central and peripheral nervous system. In this review, the authors discuss how the establishment of the Neurofibromatosis Clinical Trials Consortium (NFCTC) has positively impacted on the design and execution of treatment studies for individuals with NF1 and NF2. AREAS COVERED Using an extensive PUBMED search in collaboration with select NFCTC members expert in distinct NF topics, the authors discuss the clinical features of NF1 and NF2, the molecular biology of the NF1 and NF2 genes, the development and application of clinically relevant Nf1 and Nf2 genetically engineered mouse models and the formation of the NFCTC to enable efficient clinical trial design and execution. EXPERT OPINION The NFCTC has resulted in a more seamless integration of mouse preclinical and human clinical trials efforts. Leveraging emerging enabling resources, current research is focused on identifying subtypes of tumors in NF1 and NF2 to deliver the most active compounds to the patients most likely to respond to the targeted therapy.
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Affiliation(s)
- David H Gutmann
- Washington University School of Medicine, Department of Neurology and Washington University Neurofibromatosis Center, 660 South Euclid Avenue, St. Louis, MO 63110, USA.
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Soucy EA, van Oppen D, Nejedly NL, Gao F, Gutmann DH, Hollander AS. Height assessments in children with neurofibromatosis type 1. J Child Neurol 2013; 28:303-7. [PMID: 22752476 PMCID: PMC3947790 DOI: 10.1177/0883073812446310] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Previous studies have suggested that children with neurofibromatosis type 1 (NF1) are shorter than their unaffected counterparts. Unfortunately, these reports did not consider other contributing factors that might also influence short stature. The purpose of the current study was to characterize the genetic influence of NF1 on the growth of children. Height data were measured and recorded for 170 patients, whereas parental measurements were obtained for 61 patients to calculate sex-corrected mid-parental target heights. Children with NF1 had population mean height and mid-parental height z scores statistically different from the general population. Importantly, these differences were pronounced when neither parent had NF1 but were not significant when one of the parents had NF1. Moreover, height z scores for children with NF1 were also statistically different than their unaffected siblings. Collectively, these data establish a clear effect of a germline NF1 gene mutation on stature in children with NF1.
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Affiliation(s)
- Elizabeth A. Soucy
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110
| | - Dorothy van Oppen
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110
| | - Nicole L. Nejedly
- Department of Pediatrics, Washington University School of Medicine, St. Louis, MO 63110
| | - Feng Gao
- Division of Biostatistics, Washington University School of Medicine, St. Louis, MO 63110
| | - David H. Gutmann
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110
| | - Abby S. Hollander
- Department of Pediatrics, Washington University School of Medicine, St. Louis, MO 63110
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He Y, Rhodes SD, Chen S, Wu X, Yuan J, Yang X, Jiang L, Li X, Takahashi N, Xu M, Mohammad KS, Guise TA, Yang FC. c-Fms signaling mediates neurofibromatosis Type-1 osteoclast gain-in-functions. PLoS One 2012; 7:e46900. [PMID: 23144792 PMCID: PMC3492362 DOI: 10.1371/journal.pone.0046900] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2012] [Accepted: 09/06/2012] [Indexed: 12/19/2022] Open
Abstract
Skeletal abnormalities including osteoporosis and osteopenia occur frequently in both pediatric and adult neurofibromatosis type 1 (NF1) patients. NF1 (Nf1) haploinsufficient osteoclasts and osteoclast progenitors derived from both NF1 patients and Nf1(+/-) mice exhibit increased differentiation, migration, and bone resorptive capacity in vitro, mediated by hyperactivation of p21(Ras) in response to limiting concentrations of macrophage-colony stimulating factor (M-CSF). Here, we show that M-CSF binding to its receptor, c-Fms, results in increased c-Fms activation in Nf1(+/) (-) osteoclast progenitors, mediating multiple gain-in-functions through the downstream effectors Erk1/2 and p90RSK. PLX3397, a potent and selective c-Fms inhibitor, attenuated M-CSF mediated Nf1(+/-) osteoclast migration by 50%, adhesion by 70%, and pit formation by 60%. In vivo, we administered PLX3397 to Nf1(+/-) osteoporotic mice induced by ovariectomy (OVX) and evaluated changes in bone mass and skeletal architecture. We found that PLX3397 prevented bone loss in Nf1(+/-)-OVX mice by reducing osteoclast differentiation and bone resorptive activity in vivo. Collectively, these results implicate the M-CSF/c-Fms signaling axis as a critical pathway underlying the aberrant functioning of Nf1 haploinsufficient osteoclasts and may provide a potential therapeutic target for treating NF1 associated osteoporosis and osteopenia.
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Affiliation(s)
- Yongzheng He
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Steven D. Rhodes
- Department of Anatomy and Cell Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Shi Chen
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Xiaohua Wu
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Jin Yuan
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Xianlin Yang
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Li Jiang
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Xianqi Li
- Division of Hard Tissue Research, Matsumoto Dental University, Shiojiri, Nagano, Japan
| | - Naoyuki Takahashi
- Division of Hard Tissue Research, Matsumoto Dental University, Shiojiri, Nagano, Japan
| | - Mingjiang Xu
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Khalid S. Mohammad
- Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Theresa A. Guise
- Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - Feng-Chun Yang
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
- * E-mail:
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Alanne MH, Siljamäki E, Peltonen S, Väänänen K, Windle JJ, Parada LF, Määttä JA, Peltonen J. Phenotypic characterization of transgenic mice harboring Nf1+/− or Nf1−/− osteoclasts in otherwise Nf1+/+ background. J Cell Biochem 2012; 113:2136-46. [DOI: 10.1002/jcb.24088] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Tong HX, Li M, Zhang Y, Zhu J, Lu WQ. A novel NF1 mutation in a Chinese patient with giant café-au-lait macule in neurofibromatosis type 1 associated with a malignant peripheral nerve sheath tumor and bone abnormality. GENETICS AND MOLECULAR RESEARCH 2012; 11:2972-8. [DOI: 10.4238/2012.july.10.6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Wang HF, Shih YT, Chen CY, Chao HW, Lee MJ, Hsueh YP. Valosin-containing protein and neurofibromin interact to regulate dendritic spine density. J Clin Invest 2011; 121:4820-37. [PMID: 22105171 DOI: 10.1172/jci45677] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2010] [Accepted: 09/21/2011] [Indexed: 01/11/2023] Open
Abstract
Inclusion body myopathy with Paget disease of bone and frontotemporal dementia (IBMPFD) is an autosomal dominant disorder characterized by progressive myopathy that is often accompanied by bone weakening and/or frontotemporal dementia. Although it is known to be caused by mutations in the gene encoding valosin-containing protein (VCP), the underlying disease mechanism remains elusive. Like IBMPFD, neurofibromatosis type 1 (NF1) is an autosomal dominant disorder. Neurofibromin, the protein encoded by the NF1 gene, has been shown to regulate synaptogenesis. Here, we show that neurofibromin and VCP interact and work together to control the density of dendritic spines. Certain mutations identified in IBMPFD and NF1 patients reduced the interaction between VCP and neurofibromin and impaired spinogenesis. The functions of neurofibromin and VCP in spinogenesis were shown to correlate with the learning disability and dementia phenotypes seen in patients with IBMPFD. Consistent with the previous finding that treatment with a statin rescues behavioral defects in Nf1(+/-) mice and providing further support for our hypothesis that there is crosstalk between neurofibromin and VCP, statin exposure neutralized the effect of VCP knockdown on spinogenesis in cultured hippocampal neurons. The data presented here demonstrate that there is a link between IBMPFD and NF1 and indicate a role for VCP in synapse formation.
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Affiliation(s)
- Hsiao-Fang Wang
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
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The haploinsufficient hematopoietic microenvironment is critical to the pathological fracture repair in murine models of neurofibromatosis type 1. PLoS One 2011; 6:e24917. [PMID: 21980365 PMCID: PMC3182976 DOI: 10.1371/journal.pone.0024917] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2011] [Accepted: 08/19/2011] [Indexed: 12/28/2022] Open
Abstract
Germline mutations in the NF1 tumor suppressor gene cause neurofibromatosis type 1 (NF1), a complex genetic disorder with a high predisposition of numerous skeletal dysplasias including short stature, osteoporosis, kyphoscoliosis, and fracture non-union (pseudoarthrosis). We have developed murine models that phenocopy many of the skeletal dysplasias observed in NF1 patients, including reduced bone mass and fracture non-union. We also show that the development of these skeletal manifestations requires an Nf1 haploinsufficient background in addition to nullizygous loss of Nf1 in mesenchymal stem/progenitor cells (MSCs) and/or their progenies. This is replicated in two animal models of NF1, PeriCre+;Nf1flox/− and Col2.3Cre+;Nf1flox/−mice. Adoptive transfer experiments demonstrate a critical role of the Nf1+/− marrow microenvironment in the impaired fracture healing in both models and adoptive transfer of WT bone marrow cells improves fracture healing in these mice. To our knowledge, this is the first demonstration of a non-cell autonomous mechanism in non-malignant NF1 manifestations. Collectively, these data provide evidence of a combinatory effect between nullizygous loss of Nf1 in osteoblast progenitors and haploinsufficiency in hematopoietic cells in the development of non-malignant NF1 manifestations.
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