1
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Zhu S, Chen W, Masson A, Li YP. Cell signaling and transcriptional regulation of osteoblast lineage commitment, differentiation, bone formation, and homeostasis. Cell Discov 2024; 10:71. [PMID: 38956429 PMCID: PMC11219878 DOI: 10.1038/s41421-024-00689-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Accepted: 05/04/2024] [Indexed: 07/04/2024] Open
Abstract
The initiation of osteogenesis primarily occurs as mesenchymal stem cells undergo differentiation into osteoblasts. This differentiation process plays a crucial role in bone formation and homeostasis and is regulated by two intricate processes: cell signal transduction and transcriptional gene expression. Various essential cell signaling pathways, including Wnt, BMP, TGF-β, Hedgehog, PTH, FGF, Ephrin, Notch, Hippo, and Piezo1/2, play a critical role in facilitating osteoblast differentiation, bone formation, and bone homeostasis. Key transcriptional factors in this differentiation process include Runx2, Cbfβ, Runx1, Osterix, ATF4, SATB2, and TAZ/YAP. Furthermore, a diverse array of epigenetic factors also plays critical roles in osteoblast differentiation, bone formation, and homeostasis at the transcriptional level. This review provides an overview of the latest developments and current comprehension concerning the pathways of cell signaling, regulation of hormones, and transcriptional regulation of genes involved in the commitment and differentiation of osteoblast lineage, as well as in bone formation and maintenance of homeostasis. The paper also reviews epigenetic regulation of osteoblast differentiation via mechanisms, such as histone and DNA modifications. Additionally, we summarize the latest developments in osteoblast biology spurred by recent advancements in various modern technologies and bioinformatics. By synthesizing these insights into a comprehensive understanding of osteoblast differentiation, this review provides further clarification of the mechanisms underlying osteoblast lineage commitment, differentiation, and bone formation, and highlights potential new therapeutic applications for the treatment of bone diseases.
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Affiliation(s)
- Siyu Zhu
- Division in Cellular and Molecular Medicine, Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, Tulane University, New Orleans, LA, USA
| | - Wei Chen
- Division in Cellular and Molecular Medicine, Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, Tulane University, New Orleans, LA, USA.
| | - Alasdair Masson
- Division in Cellular and Molecular Medicine, Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, Tulane University, New Orleans, LA, USA
| | - Yi-Ping Li
- Division in Cellular and Molecular Medicine, Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, Tulane University, New Orleans, LA, USA.
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2
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Wu M, Wu S, Chen W, Li YP. The roles and regulatory mechanisms of TGF-β and BMP signaling in bone and cartilage development, homeostasis and disease. Cell Res 2024; 34:101-123. [PMID: 38267638 PMCID: PMC10837209 DOI: 10.1038/s41422-023-00918-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2023] [Accepted: 12/15/2023] [Indexed: 01/26/2024] Open
Abstract
Transforming growth factor-βs (TGF-βs) and bone morphometric proteins (BMPs) belong to the TGF-β superfamily and perform essential functions during osteoblast and chondrocyte lineage commitment and differentiation, skeletal development, and homeostasis. TGF-βs and BMPs transduce signals through SMAD-dependent and -independent pathways; specifically, they recruit different receptor heterotetramers and R-Smad complexes, resulting in unique biological readouts. BMPs promote osteogenesis, osteoclastogenesis, and chondrogenesis at all differentiation stages, while TGF-βs play different roles in a stage-dependent manner. BMPs and TGF-β have opposite functions in articular cartilage homeostasis. Moreover, TGF-β has a specific role in maintaining the osteocyte network. The precise activation of BMP and TGF-β signaling requires regulatory machinery at multiple levels, including latency control in the matrix, extracellular antagonists, ubiquitination and phosphorylation in the cytoplasm, nucleus-cytoplasm transportation, and transcriptional co-regulation in the nuclei. This review weaves the background information with the latest advances in the signaling facilitated by TGF-βs and BMPs, and the advanced understanding of their diverse physiological functions and regulations. This review also summarizes the human diseases and mouse models associated with disordered TGF-β and BMP signaling. A more precise understanding of the BMP and TGF-β signaling could facilitate the development of bona fide clinical applications in treating bone and cartilage disorders.
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Affiliation(s)
- Mengrui Wu
- Department of Cell and Developmental Biology, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China.
| | - Shali Wu
- Department of Cell and Developmental Biology, College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Wei Chen
- Division in Cellular and Molecular Medicine, Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, Tulane University, New Orleans, LA, USA
| | - Yi-Ping Li
- Division in Cellular and Molecular Medicine, Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, Tulane University, New Orleans, LA, USA.
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3
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Loh HY, Norman BP, Lai KS, Cheng WH, Nik Abd Rahman NMA, Mohamed Alitheen NB, Osman MA. Post-Transcriptional Regulatory Crosstalk between MicroRNAs and Canonical TGF-β/BMP Signalling Cascades on Osteoblast Lineage: A Comprehensive Review. Int J Mol Sci 2023; 24:ijms24076423. [PMID: 37047394 PMCID: PMC10094338 DOI: 10.3390/ijms24076423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 12/22/2022] [Accepted: 12/22/2022] [Indexed: 04/14/2023] Open
Abstract
MicroRNAs (miRNAs) are a family of small, single-stranded, and non-protein coding RNAs about 19 to 22 nucleotides in length, that have been reported to have important roles in the control of bone development. MiRNAs have a strong influence on osteoblast differentiation through stages of lineage commitment and maturation, as well as via controlling the activities of osteogenic signal transduction pathways. Generally, miRNAs may modulate cell stemness, proliferation, differentiation, and apoptosis by binding the 3'-untranslated regions (3'-UTRs) of the target genes, which then can subsequently undergo messenger RNA (mRNA) degradation or protein translational repression. MiRNAs manage the gene expression in osteogenic differentiation by regulating multiple signalling cascades and essential transcription factors, including the transforming growth factor-beta (TGF-β)/bone morphogenic protein (BMP), Wingless/Int-1(Wnt)/β-catenin, Notch, and Hedgehog signalling pathways; the Runt-related transcription factor 2 (RUNX2); and osterix (Osx). This shows that miRNAs are essential in regulating diverse osteoblast cell functions. TGF-βs and BMPs transduce signals and exert diverse functions in osteoblastogenesis, skeletal development and bone formation, bone homeostasis, and diseases. Herein, we highlighted the current state of in vitro and in vivo research describing miRNA regulation on the canonical TGF-β/BMP signalling, their effects on osteoblast linage, and understand their mechanism of action for the development of possible therapeutics. In this review, particular attention and comprehensive database searches are focused on related works published between the years 2000 to 2022, using the resources from PubMed, Google Scholar, Scopus, and Web of Science.
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Affiliation(s)
- Hui-Yi Loh
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang 43400, Selangor, Malaysia
| | - Brendan P Norman
- Department of Musculoskeletal and Ageing Science, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool L7 8TX, UK
| | - Kok-Song Lai
- Health Sciences Division, Abu Dhabi Women's College, Higher Colleges of Technology, Abu Dhabi 41012, United Arab Emirates
| | - Wan-Hee Cheng
- Faculty of Health and Life Sciences, INTI International University, Persiaran Perdana BBN, Putra Nilai, Nilai 71800, Negeri Sembilan, Malaysia
| | - Nik Mohd Afizan Nik Abd Rahman
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang 43400, Selangor, Malaysia
| | - Noorjahan Banu Mohamed Alitheen
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang 43400, Selangor, Malaysia
| | - Mohd Azuraidi Osman
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang 43400, Selangor, Malaysia
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4
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Mesenchymal Stem Cells and Their Exocytotic Vesicles. Int J Mol Sci 2023; 24:ijms24032085. [PMID: 36768406 PMCID: PMC9916886 DOI: 10.3390/ijms24032085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 01/16/2023] [Accepted: 01/18/2023] [Indexed: 01/21/2023] Open
Abstract
Mesenchymal stem cells (MSCs), as a kind of pluripotent stem cells, have attracted much attention in orthopedic diseases, geriatric diseases, metabolic diseases, and sports functions due to their osteogenic potential, chondrogenic differentiation ability, and adipocyte differentiation. Anti-inflammation, anti-fibrosis, angiogenesis promotion, neurogenesis, immune regulation, and secreted growth factors, proteases, hormones, cytokines, and chemokines of MSCs have been widely studied in liver and kidney diseases, cardiovascular and cerebrovascular diseases. In recent years, many studies have shown that the extracellular vesicles of MSCs have similar functions to MSCs transplantation in all the above aspects. Here we review the research progress of MSCs and their exocrine vesicles in recent years.
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Smith SS, Chu D, Qu T, Aggleton JA, Schneider RA. Species-specific sensitivity to TGFβ signaling and changes to the Mmp13 promoter underlie avian jaw development and evolution. eLife 2022; 11:e66005. [PMID: 35666955 PMCID: PMC9246370 DOI: 10.7554/elife.66005] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Accepted: 06/03/2022] [Indexed: 12/02/2022] Open
Abstract
Precise developmental control of jaw length is critical for survival, but underlying molecular mechanisms remain poorly understood. The jaw skeleton arises from neural crest mesenchyme (NCM), and we previously demonstrated that these progenitor cells express more bone-resorbing enzymes including Matrix metalloproteinase 13 (Mmp13) when they generate shorter jaws in quail embryos versus longer jaws in duck. Moreover, if we inhibit bone resorption or Mmp13, we can increase jaw length. In the current study, we uncover mechanisms establishing species-specific levels of Mmp13 and bone resorption. Quail show greater activation of and sensitivity to transforming growth factor beta (TGFβ) signaling than duck; where intracellular mediators like SMADs and targets like Runt-related transcription factor 2 (Runx2), which bind Mmp13, become elevated. Inhibiting TGFβ signaling decreases bone resorption, and overexpressing Mmp13 in NCM shortens the duck lower jaw. To elucidate the basis for this differential regulation, we examine the Mmp13 promoter. We discover a SMAD-binding element and single nucleotide polymorphisms (SNPs) near a RUNX2-binding element that distinguish quail from duck. Altering the SMAD site and switching the SNPs abolish TGFβ sensitivity in the quail Mmp13 promoter but make the duck promoter responsive. Thus, differential regulation of TGFβ signaling and Mmp13 promoter structure underlie avian jaw development and evolution.
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Affiliation(s)
- Spenser S Smith
- Department of Orthopaedic Surgery, University of California, San FranciscoSan FranciscoUnited States
| | - Daniel Chu
- Department of Orthopaedic Surgery, University of California, San FranciscoSan FranciscoUnited States
| | - Tiange Qu
- Department of Orthopaedic Surgery, University of California, San FranciscoSan FranciscoUnited States
| | - Jessye A Aggleton
- Department of Orthopaedic Surgery, University of California, San FranciscoSan FranciscoUnited States
| | - Richard A Schneider
- Department of Orthopaedic Surgery, University of California, San FranciscoSan FranciscoUnited States
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6
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MicroRNAs and osteosarcoma: Potential targets for inhibiting metastasis and increasing chemosensitivity. Biochem Pharmacol 2022; 201:115094. [PMID: 35588853 DOI: 10.1016/j.bcp.2022.115094] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 05/10/2022] [Accepted: 05/11/2022] [Indexed: 12/12/2022]
Abstract
Osteosarcoma (OS) is the third most common cancer in young adults after lymphoma and brain cancer. Metastasis, like other cellular events, is dependent on signaling pathways; a series of changes in some proteins and signaling pathways pave the way for OS cells to invade and migrate. Ezrin, TGF-β, Notch, RUNX2, matrix metalloproteinases (MMPs), Wnt/β-catenin, and phosphoinositide 3-kinase (PI3K)/AKT are among the most important of these proteins and signaling pathways. Despite the improvements in treating OS, the overall survival of patients suffering from the metastatic disease has not experienced any significant change after surgical treatments and chemotherapy and 5-years overall survival in patients with metastatic OS is about 20%. Studies have shown that overexpression or inhibition of some microRNAs (miRNAs) has significant effects in limiting the invasion and migration of OS cells. The results of these studies highlight the potential of the clinical application of some miRNA mimics and miRNA inhibitors (antagomiRs) to inhibit OS metastasis in the future. In addition, some studies have shown that miRNAs are associated with the most important drug resistance mechanisms in OS, and some miRNAs are highly effective targets to increase chemosensitivity. The results of these studies suggest that miRNA mimics and antagomiRs may be helpful to increase the efficacy of conventional chemotherapy drugs in the treatment of metastatic OS. In this article, we discussed the role of various signaling pathways and the involved miRNAs in the metastasis of OS, attempting to provide a comprehensive review of the literature on OS metastasis and chemosensitivity.
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7
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Zhang Y, Lu W, Zhao Q, Chen J, Wang T, Ji J. The role of the protein tyrosine phosphatase SHP2 in ossification. Dev Dyn 2021; 251:748-758. [PMID: 34962674 DOI: 10.1002/dvdy.449] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 12/09/2021] [Accepted: 12/21/2021] [Indexed: 12/16/2022] Open
Abstract
SHP2, encoded by the PTPN11 gene, participates in multiple cell functions including cell proliferation, movement, and differentiation. PTPN11 loss-of-function and gain-of-function mutations are both associated with diseases, such as Noonan syndrome, whose manifestations include bone defects, suggesting a crucial role for SHP2 in the skeleton. However, the exact mechanisms by which SHP2 regulates bone development remain unclear. This review focuses on the current understanding of the regulation of SHP2 and highlights the vital roles of SHP2 in skeletal development, especially its roles in ossification. Overall, a better understanding of the functions of SHP2 in ossification will provide a new avenue to treat-related skeletal diseases.
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Affiliation(s)
- Yuan Zhang
- Department of Orthodontics, Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing, People's Republic of China.,Nanjing Key Laboratory, Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing, People's Republic of China
| | - Wei Lu
- Department of Prosthodontics, Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing, People's Republic of China
| | - Qing Zhao
- Department of Orthodontics, Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing, People's Republic of China.,Nanjing Key Laboratory, Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing, People's Republic of China
| | - Jindong Chen
- Department of Orthodontics, Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing, People's Republic of China
| | - Tiancong Wang
- Department of Orthodontics, Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing, People's Republic of China
| | - Jun Ji
- Department of Orthodontics, Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing, People's Republic of China.,Nanjing Key Laboratory, Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing, People's Republic of China
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8
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Peng CH, Lin WY, Yeh KT, Chen IH, Wu WT, Lin MD. The molecular etiology and treatment of glucocorticoid-induced osteoporosis. Tzu Chi Med J 2021; 33:212-223. [PMID: 34386357 PMCID: PMC8323641 DOI: 10.4103/tcmj.tcmj_233_20] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 11/19/2020] [Accepted: 12/30/2020] [Indexed: 12/30/2022] Open
Abstract
Glucocorticoid-induced osteoporosis (GIOP) is the most common form of secondary osteoporosis, accounting for 20% of osteoporosis diagnoses. Using glucocorticoids for >6 months leads to osteoporosis in 50% of patients, resulting in an increased risk of fracture and death. Osteoblasts, osteocytes, and osteoclasts work together to maintain bone homeostasis. When bone formation and resorption are out of balance, abnormalities in bone structure or function may occur. Excess glucocorticoids disrupt the bone homeostasis by promoting osteoclast formation and prolonging osteoclasts' lifespan, leading to an increase in bone resorption. On the other hand, glucocorticoids inhibit osteoblasts' formation and facilitate apoptosis of osteoblasts and osteocytes, resulting in a reduction of bone formation. Several signaling pathways, signaling modulators, endocrines, and cytokines are involved in the molecular etiology of GIOP. Clinically, adults ≥40 years of age using glucocorticoids chronically with a high fracture risk are considered to have medical intervention. In addition to vitamin D and calcium tablet supplementations, the major therapeutic options approved for GIOP treatment include antiresorption drug bisphosphonates, parathyroid hormone N-terminal fragment teriparatide, and the monoclonal antibody denosumab. The selective estrogen receptor modulator can only be used under specific condition for postmenopausal women who have GIOP but fail to the regular GIOP treatment or have specific therapeutic contraindications. In this review, we focus on the molecular etiology of GIOP and the molecular pharmacology of the therapeutic drugs used for GIOP treatment.
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Affiliation(s)
- Cheng-Huan Peng
- Department of Orthopedics, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Hualien, Taiwan.,Institute of Medical Sciences, Tzu Chi University, Hualien, Taiwan.,School of Medicine, Tzu Chi University, Hualien, Taiwan
| | - Wen-Ying Lin
- Department of Orthopedics, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Hualien, Taiwan
| | - Kuang-Ting Yeh
- Department of Orthopedics, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Hualien, Taiwan.,School of Medicine, Tzu Chi University, Hualien, Taiwan
| | - Ing-Ho Chen
- Department of Orthopedics, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Hualien, Taiwan.,School of Medicine, Tzu Chi University, Hualien, Taiwan
| | - Wen-Tien Wu
- Department of Orthopedics, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Hualien, Taiwan.,Institute of Medical Sciences, Tzu Chi University, Hualien, Taiwan.,School of Medicine, Tzu Chi University, Hualien, Taiwan
| | - Ming-Der Lin
- Institute of Medical Sciences, Tzu Chi University, Hualien, Taiwan.,Department of Molecular Biology and Human Genetics, Tzu Chi University, Hualien, Taiwan
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9
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Montecino M, Carrasco ME, Nardocci G. Epigenetic Control of Osteogenic Lineage Commitment. Front Cell Dev Biol 2021; 8:611197. [PMID: 33490076 PMCID: PMC7820369 DOI: 10.3389/fcell.2020.611197] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 12/11/2020] [Indexed: 12/22/2022] Open
Abstract
Within the eukaryotic nucleus the genomic DNA is organized into chromatin by stably interacting with the histone proteins as well as with several other nuclear components including non-histone proteins and non-coding RNAs. Together these interactions distribute the genetic material into chromatin subdomains which can exhibit higher and lower compaction levels. This organization contributes to differentially control the access to genomic sequences encoding key regulatory genetic information. In this context, epigenetic mechanisms play a critical role in the regulation of gene expression as they modify the degree of chromatin compaction to facilitate both activation and repression of transcription. Among the most studied epigenetic mechanisms we find the methylation of DNA, ATP-dependent chromatin remodeling, and enzyme-mediated deposition and elimination of post-translational modifications at histone and non-histone proteins. In this mini review, we discuss evidence that supports the role of these epigenetic mechanisms during transcriptional control of osteoblast-related genes. Special attention is dedicated to mechanisms of epigenetic control operating at the Runx2 and Sp7 genes coding for the two principal master regulators of the osteogenic lineage during mesenchymal stem cell commitment.
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Affiliation(s)
- Martin Montecino
- Faculty of Medicine and Faculty of Life Sciences, Institute of Biomedical Sciences and FONDAP Center for Genome Regulation, Universidad Andres Bello, Santiago, Chile
| | - Margarita E Carrasco
- Faculty of Medicine and Faculty of Life Sciences, Institute of Biomedical Sciences and FONDAP Center for Genome Regulation, Universidad Andres Bello, Santiago, Chile
| | - Gino Nardocci
- Faculty of Medicine, Universidad de los Andes, Santiago, Chile.,Molecular Biology and Bioinformatic Lab, Program in Molecular Biology and Bioinformatics, Center for Biomedical Research and Innovation (CIIB), Universidad de los Andes, Santiago, Chile
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10
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Jiang X, Zhang Z, Song C, Deng H, Yang R, Zhou L, Sun Y, Zhang Q. Glaucocalyxin A reverses EMT and TGF-β1-induced EMT by inhibiting TGF-β1/Smad2/3 signaling pathway in osteosarcoma. Chem Biol Interact 2019; 307:158-166. [PMID: 31059706 DOI: 10.1016/j.cbi.2019.05.005] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 04/27/2019] [Accepted: 05/03/2019] [Indexed: 02/07/2023]
Abstract
Metastatic osteosarcoma usually has an unsatisfactory response to the current standard chemotherapy and causes poor prognosis. Currently, epithelial-mesenchymal transition (EMT) is reported as a critical event in osteosarcoma metastasis. Glaucocalyxin A, a bioactive ent-kauranoid diterpenoid, exerts anti-cancer effect on osteosarcoma by inducing apoptosis in previous study. However, the effect of Glaucocalyxin A on EMT and metastasis of osteosarcoma is unclear. In this study, we investigated the potential mechanisms of Glaucocalyxin A on EMT and metastasis of osteosarcoma. We found that Glaucocalyxin A inhibited migration and invasion of MG-63 and 143B cells. Moreover, Glaucocalyxin A increased the protein and mRNA levels of E-cadherin and decreased the protein and transcription expression of N-cadherin, Vimentin. Glaucocalyxin A also inhibited the protein and mRNA levels of EMT-associated transcription factor including Snail and Slug. Furthermore, Glaucocalyxin A inhibited transforming growth factor-β1 (TGF-β1)-induced migration, invasion and EMT of low-metastatic osteosarcoma U2OS cells. Glaucocalyxin A inhibited TGF-β-induced phosphorylation of Smad 2/3 in osteosarcoma U2OS cells. Finally, we established transplanted metastatic models of highly metastatic osteosarcoma 143B cells. Glaucocalyxin A inhibited lung metastasis in vivo. Interestingly, Glaucocalyxin A increased the protein expression of E-cadherin and reduced the protein expression of N-cadherin and Vimentin. Glaucocalyxin A inhibited the protein expression of Snail and Slug in vivo. In summary, this study demonstrated that Glaucocalyxin A inhibited EMT and TGF-β1-induced EMT by inhibiting TGF-β1/Smad2/3 signaling pathway in osteosarcoma. Therefore, Glaucocalyxin A might be a promising candidate against the metastasis of human osteosarcoma.
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Affiliation(s)
- Xiubo Jiang
- School of Pharmaceutical Sciences, Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing 211816, People's Republic of China
| | - Zhenhao Zhang
- The First Clinical Medical College, Nanjing Medical University, 101Longmian Avenue, Jiangning District, Nanjing 211166, People's Republic of China
| | - Changqin Song
- School of Pharmaceutical Sciences, Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing 211816, People's Republic of China
| | - Hanzhi Deng
- School of Pharmaceutical Sciences, Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing 211816, People's Republic of China
| | - Runyu Yang
- School of Pharmaceutical Sciences, Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing 211816, People's Republic of China
| | - Lvqi Zhou
- School of Pharmaceutical Sciences, Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing 211816, People's Republic of China
| | - Yang Sun
- School of Pharmaceutical Sciences, Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing 211816, People's Republic of China.
| | - Qi Zhang
- School of Pharmaceutical Sciences, Nanjing Tech University (NanjingTech), 30 South Puzhu Road, Nanjing 211816, People's Republic of China.
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11
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Wang L, Huang J, Moore DC, Song Y, Ehrlich MG, Yang W. SHP2 regulates intramembranous ossification by modifying the TGFβ and BMP2 signaling pathway. Bone 2019; 120:327-335. [PMID: 30471432 PMCID: PMC6360127 DOI: 10.1016/j.bone.2018.11.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 11/07/2018] [Accepted: 11/20/2018] [Indexed: 02/05/2023]
Abstract
SHP2 is a ubiquitously expressed protein tyrosine phosphatase, which is involved in many signaling pathways to regulate the skeletal development. In endochondral ossification, SHP2 is known to modify the osteogenic fate of osteochondroprogenitors and to impair the osteoblastic transdifferentiation of hypertrophic chondrocytes. However, how SHP2 regulates osteoblast differentiation in intramembranous ossification remains incompletely understood. To address this question, we generated a mouse model to ablate SHP2 in the Prrx1-expressing mesenchymal progenitors by using "Cre-loxP"-mediated gene excision and examined the development of calvarial bone, in which the main process of bone formation is intramembranous ossification. Phenotypic characterization showed that SHP2 mutants have severe defects in calvarial bone formation. Cell lineage tracing and in situ hybridization data showed less osteoblast differentiation of mesenchymal cells and reduced osteogenic genes expression, respectively. Further mechanistic studies revealed enhanced TGFβ and suppressed BMP2 signaling in SHP2 ablated mesenchymal progenitors and their derivatives. Our study uncovered the critical role of SHP2 in osteoblast differentiation through intramembranous ossification and might provide a potential target to treat craniofacial skeleton disorders.
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Affiliation(s)
- Lijun Wang
- Department of Orthopaedics, Brown University Alpert Medical School and Rhode Island Hospital, Providence, RI 02903, United States of America
| | - Jiahui Huang
- Department of Orthopaedics, Brown University Alpert Medical School and Rhode Island Hospital, Providence, RI 02903, United States of America
| | - Douglas C Moore
- Department of Orthopaedics, Brown University Alpert Medical School and Rhode Island Hospital, Providence, RI 02903, United States of America
| | - Yueming Song
- Department of Orthopedic Surgery, West China Hospital of Sichuan University, Chengdu 610041, P.R. China
| | - Michael G Ehrlich
- Department of Orthopaedics, Brown University Alpert Medical School and Rhode Island Hospital, Providence, RI 02903, United States of America
| | - Wentian Yang
- Department of Orthopaedics, Brown University Alpert Medical School and Rhode Island Hospital, Providence, RI 02903, United States of America.
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12
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Li H, Fan J, Fan L, Li T, Yang Y, Xu H, Deng L, Li J, Li T, Weng X, Wang S, Chunhua Zhao R. MiRNA-10b Reciprocally Stimulates Osteogenesis and Inhibits Adipogenesis Partly through the TGF-β/SMAD2 Signaling Pathway. Aging Dis 2018; 9:1058-1073. [PMID: 30574418 PMCID: PMC6284771 DOI: 10.14336/ad.2018.0214] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 02/14/2018] [Indexed: 12/15/2022] Open
Abstract
As the population ages, the medical and socioeconomic impact of age-related bone disorders will further increase. An imbalance between osteogenesis and adipogenesis of mesenchymal stem cells (MSCs) can lead to various bone and metabolic diseases such as osteoporosis. Thus, understanding the molecular mechanisms underlying MSC osteogenic and adipogenic differentiation is important for the discovery of novel therapeutic paradigms for these diseases. miR-10b has been widely reported in tumorigenesis, cancer invasion and metastasis. However, the effects and potential mechanisms of miR-10b in the regulation of MSC adipogenic and osteogenic differentiation have not been explored. In this study, we found that the expression of miR-10b was positively correlated with bone formation marker genes ALP, RUNX2 and OPN, and negatively correlated with adipogenic markers CEBPα, PPARγ and AP2 in clinical osteoporosis samples. Overexpression of miR-10b enhanced osteogenic differentiation and inhibited adipogenic differentiation of human adipose-derived mesenchymal stem cells (hADSCs) in vitro, whereas downregulation of miR-10b reversed these effects. Furthermore, miR-10b promoted ectopic bone formation in vivo. Target prediction and dual luciferase reporter assays identified SMAD2 as a potential target of miR-10b. Silencing endogenous SMAD2 expression in hADSCs enhanced osteogenesis but repressed adipogenesis. Pathway analysis indicated that miR-10b promotes osteogenic differentiation and bone formation via the TGF-β signaling pathway, while suppressing adipogenic differentiation may be primarily mediated by other pathways. Taken together, our findings imply that miR-10b acts as a critical regulator for balancing osteogenic and adipogenic differentiation of hADSCs by repressing SMAD2 and partly through the TGF-β pathway. Our study suggests that miR-10b is a novel target for controlling bone and metabolic diseases.
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Affiliation(s)
- Hongling Li
- 1Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Center of Excellence in Tissue Engineering Chinese Academy of Medical Sciences, Beijing Key Laboratory (No. BZO381), Beijing 100005, China
| | - Junfen Fan
- 1Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Center of Excellence in Tissue Engineering Chinese Academy of Medical Sciences, Beijing Key Laboratory (No. BZO381), Beijing 100005, China
| | - Linyuan Fan
- 1Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Center of Excellence in Tissue Engineering Chinese Academy of Medical Sciences, Beijing Key Laboratory (No. BZO381), Beijing 100005, China
| | - Tangping Li
- 1Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Center of Excellence in Tissue Engineering Chinese Academy of Medical Sciences, Beijing Key Laboratory (No. BZO381), Beijing 100005, China
| | - Yanlei Yang
- 1Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Center of Excellence in Tissue Engineering Chinese Academy of Medical Sciences, Beijing Key Laboratory (No. BZO381), Beijing 100005, China
| | - Haoying Xu
- 1Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Center of Excellence in Tissue Engineering Chinese Academy of Medical Sciences, Beijing Key Laboratory (No. BZO381), Beijing 100005, China
| | - Luchan Deng
- 1Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Center of Excellence in Tissue Engineering Chinese Academy of Medical Sciences, Beijing Key Laboratory (No. BZO381), Beijing 100005, China
| | - Jing Li
- 1Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Center of Excellence in Tissue Engineering Chinese Academy of Medical Sciences, Beijing Key Laboratory (No. BZO381), Beijing 100005, China
| | - Tao Li
- 2Department of Orthopaedic Surgery, Peking Union Medical College Hospital, Peking Union Medical College, Beijing 100730, China.,3Current address: Department of Orthopaedic Surgery, The Affiliated Hospital of Qingdao University, Qingdao 266003, China
| | - Xisheng Weng
- 2Department of Orthopaedic Surgery, Peking Union Medical College Hospital, Peking Union Medical College, Beijing 100730, China
| | - Shihua Wang
- 1Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Center of Excellence in Tissue Engineering Chinese Academy of Medical Sciences, Beijing Key Laboratory (No. BZO381), Beijing 100005, China
| | - Robert Chunhua Zhao
- 1Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Center of Excellence in Tissue Engineering Chinese Academy of Medical Sciences, Beijing Key Laboratory (No. BZO381), Beijing 100005, China
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Grafe I, Alexander S, Peterson JR, Snider TN, Levi B, Lee B, Mishina Y. TGF-β Family Signaling in Mesenchymal Differentiation. Cold Spring Harb Perspect Biol 2018; 10:a022202. [PMID: 28507020 PMCID: PMC5932590 DOI: 10.1101/cshperspect.a022202] [Citation(s) in RCA: 160] [Impact Index Per Article: 26.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Mesenchymal stem cells (MSCs) can differentiate into several lineages during development and also contribute to tissue homeostasis and regeneration, although the requirements for both may be distinct. MSC lineage commitment and progression in differentiation are regulated by members of the transforming growth factor-β (TGF-β) family. This review focuses on the roles of TGF-β family signaling in mesenchymal lineage commitment and differentiation into osteoblasts, chondrocytes, myoblasts, adipocytes, and tenocytes. We summarize the reported findings of cell culture studies, animal models, and interactions with other signaling pathways and highlight how aberrations in TGF-β family signaling can drive human disease by affecting mesenchymal differentiation.
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Affiliation(s)
- Ingo Grafe
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030
| | - Stefanie Alexander
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030
| | - Jonathan R Peterson
- Department of Surgery, University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - Taylor Nicholas Snider
- Department of Biologic and Materials Sciences, School of Dentistry, University of Michigan, Ann Arbor, Michigan 48109
| | - Benjamin Levi
- Department of Surgery, University of Michigan Medical School, Ann Arbor, Michigan 48109
| | - Brendan Lee
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas 77030
| | - Yuji Mishina
- Department of Biologic and Materials Sciences, School of Dentistry, University of Michigan, Ann Arbor, Michigan 48109
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Song C, Liu W, Li J. USP17 is upregulated in osteosarcoma and promotes cell proliferation, metastasis, and epithelial–mesenchymal transition through stabilizing SMAD4. Tumour Biol 2017; 39:1010428317717138. [PMID: 28670958 DOI: 10.1177/1010428317717138] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
USP17 is upregulated in several cancers, indicating that USP17 might play essential functions in tumor development. However, the function of USP17 in osteosarcoma is still unknown. Our work aimed to investigate the function of USP17 in osteosarcoma. We found that the expression of USP17 was upregulated in osteosarcoma tissues and cell lines, including MG-63 and U2OS. Several functional experiments, such as colony formation analysis, Cell Counting Kit-8 assay, wound healing analysis, and transwell assay, showed that USP17 promoted cell proliferation, migration, and invasion. Moreover, we found that USP17 facilitated migration and invasion through promoting epithelial–mesenchymal transition. SMAD4 has been found to regulate epithelial–mesenchymal transition, co-immunopurification, and glutathione S-transferase pull-down analysis demonstrated that USP17 interacted with SMAD4. Furthermore, USP17 stabilized SMAD4 through its deubiquitinase activity. In conclusion, this study shows that USP17 enhances osteosarcoma cell proliferation and invasion through stabilizing SMAD4.
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Affiliation(s)
- Chenyang Song
- Department of Orthopedics, Fujian Medical University Union Hospital, Fuzhou, China
| | - Wenge Liu
- Department of Orthopedics, Fujian Medical University Union Hospital, Fuzhou, China
| | - Jiandong Li
- Department of Orthopedics, Fujian Medical University Union Hospital, Fuzhou, China
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15
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Wu M, Chen G, Li YP. TGF-β and BMP signaling in osteoblast, skeletal development, and bone formation, homeostasis and disease. Bone Res 2016; 4:16009. [PMID: 27563484 PMCID: PMC4985055 DOI: 10.1038/boneres.2016.9] [Citation(s) in RCA: 1009] [Impact Index Per Article: 126.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Revised: 03/04/2016] [Accepted: 03/07/2016] [Indexed: 12/11/2022] Open
Abstract
Transforming growth factor-beta (TGF-β) and bone morphogenic protein (BMP) signaling has fundamental roles in both embryonic skeletal development and postnatal bone homeostasis. TGF-βs and BMPs, acting on a tetrameric receptor complex, transduce signals to both the canonical Smad-dependent signaling pathway (that is, TGF-β/BMP ligands, receptors, and Smads) and the non-canonical-Smad-independent signaling pathway (that is, p38 mitogen-activated protein kinase/p38 MAPK) to regulate mesenchymal stem cell differentiation during skeletal development, bone formation and bone homeostasis. Both the Smad and p38 MAPK signaling pathways converge at transcription factors, for example, Runx2 to promote osteoblast differentiation and chondrocyte differentiation from mesenchymal precursor cells. TGF-β and BMP signaling is controlled by multiple factors, including the ubiquitin–proteasome system, epigenetic factors, and microRNA. Dysregulated TGF-β and BMP signaling result in a number of bone disorders in humans. Knockout or mutation of TGF-β and BMP signaling-related genes in mice leads to bone abnormalities of varying severity, which enable a better understanding of TGF-β/BMP signaling in bone and the signaling networks underlying osteoblast differentiation and bone formation. There is also crosstalk between TGF-β/BMP signaling and several critical cytokines’ signaling pathways (for example, Wnt, Hedgehog, Notch, PTHrP, and FGF) to coordinate osteogenesis, skeletal development, and bone homeostasis. This review summarizes the recent advances in our understanding of TGF-β/BMP signaling in osteoblast differentiation, chondrocyte differentiation, skeletal development, cartilage formation, bone formation, bone homeostasis, and related human bone diseases caused by the disruption of TGF-β/BMP signaling.
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Affiliation(s)
- Mengrui Wu
- Department of Pathology, University of Alabama at Birmingham , Birmingham, USA
| | - Guiqian Chen
- Department of Pathology, University of Alabama at Birmingham, Birmingham, USA; Department of neurology, Bruke Medical Research Institute, Weil Cornell Medicine of Cornell University, White Plains, USA
| | - Yi-Ping Li
- Department of Pathology, University of Alabama at Birmingham , Birmingham, USA
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16
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Grilli A, Sciandra M, Terracciano M, Picci P, Scotlandi K. Integrated approaches to miRNAs target definition: time-series analysis in an osteosarcoma differentiative model. BMC Med Genomics 2015; 8:34. [PMID: 26123714 PMCID: PMC4486310 DOI: 10.1186/s12920-015-0106-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Accepted: 06/03/2015] [Indexed: 12/25/2022] Open
Abstract
Background microRNAs (miRs) are small non-coding RNAs involved in the fine regulation of several cellular processes by inhibiting their target genes at post-transcriptional level. Osteosarcoma (OS) is a tumor thought to be related to a molecular blockade of the normal process of osteoblast differentiation. The current paper explores temporal transcriptional modifications comparing an osteosarcoma cell line, Saos-2, and clones stably transfected with CD99, a molecule which was found to drive OS cells to terminally differentiate. Methods Parental cell line and CD99 transfectants were cultured up to 14 days in differentiating medium. In this setting, OS cells were profiled by gene and miRNA expression arrays. Integration of gene and miRNA profiling was performed by both sequence complementarity and expression correlation. Further enrichment and network analyses were carried out to focus on the modulated pathways and on the interactions between transcriptome and miRNome. To track the temporal transcriptional modification, a PCA analysis with differentiated human MSC was performed. Results We identified a strong (about 80 %) gene down-modulation where reversion towards the osteoblast-like phenotype matches significant enrichment in TGFbeta signaling players like AKT1 and SMADs. In parallel, we observed the modulation of several cancer-related microRNAs like miR-34a, miR-26b or miR-378. To decipher their impact on the modified transcriptional program in CD99 cells, we correlated gene and microRNA time-series data miR-34a, in particular, was found to regulate a distinct subnetwork of genes with respect to the rest of the other differentially expressed miRs and it appeared to be the main mediator of several TGFbeta signaling genes at initial and middle phases of differentiation. Integration studies further highlighted the involvement of TGFbeta pathway in the differentiation of OS cells towards osteoblasts and its regulation by microRNAs. Conclusions These data underline that the expression of miR-34a and down-modulation of TGFbeta signaling emerge as pivotal events to drive CD99-mediated reversal of malignancy and activation of differentiation in OS cells. Our results describe crucial and specific interacting actors providing and supporting their relevance as potential targets for therapeutic differentiative strategies. Electronic supplementary material The online version of this article (doi:10.1186/s12920-015-0106-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- A Grilli
- Laboratory of Experimental Oncology, CRS Development of Biomolecular Therapies, Rizzoli Orthopedic Institute, Via di Barbiano 1/10, 40136, Bologna, Italy.
| | - M Sciandra
- Laboratory of Experimental Oncology, CRS Development of Biomolecular Therapies, Rizzoli Orthopedic Institute, Via di Barbiano 1/10, 40136, Bologna, Italy. .,PROMETEO, STB, RIT Department, Rizzoli Orthopedic Institute, Bologna, Italy.
| | - M Terracciano
- Laboratory of Experimental Oncology, CRS Development of Biomolecular Therapies, Rizzoli Orthopedic Institute, Via di Barbiano 1/10, 40136, Bologna, Italy.
| | - P Picci
- Laboratory of Experimental Oncology, CRS Development of Biomolecular Therapies, Rizzoli Orthopedic Institute, Via di Barbiano 1/10, 40136, Bologna, Italy.
| | - K Scotlandi
- Laboratory of Experimental Oncology, CRS Development of Biomolecular Therapies, Rizzoli Orthopedic Institute, Via di Barbiano 1/10, 40136, Bologna, Italy. .,PROMETEO, STB, RIT Department, Rizzoli Orthopedic Institute, Bologna, Italy.
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Przybylowski C, Quinn T, Callahan A, Kaplan M, Golding A, Alesi C, Ammar M, LeBlon CE, Guo Y, Zhang X, Jedlicka SS. MC3T3 preosteoblast differentiation on bone morphogenetic protein-2 peptide ormosils. ACTA ACUST UNITED AC 2012. [DOI: 10.1039/c2jm16490f] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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18
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Pino AM, Rosen CJ, Rodríguez JP. In osteoporosis, differentiation of mesenchymal stem cells (MSCs) improves bone marrow adipogenesis. Biol Res 2012; 45:279-87. [PMID: 23283437 PMCID: PMC8262098 DOI: 10.4067/s0716-97602012000300009] [Citation(s) in RCA: 146] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Accepted: 08/23/2012] [Indexed: 01/01/2023] Open
Abstract
The formation, maintenance, and repair of bone tissue involve close interlinks between two stem cell types housed in the bone marrow: the hematologic stem cell originating osteoclasts and mesenchymal stromal cells (MSCs) generating osteoblasts. In this review, we consider malfunctioning of MSCs as essential for osteoporosis. In osteoporosis, increased bone fragility and susceptibility to fractures result from increased osteoclastogenesis and insufficient osteoblastogenesis. MSCs are the common precursors for both osteoblasts and adipocytes, among other cell types. MSCs' commitment towards either the osteoblast or adipocyte lineages depends on suitable regulatory factors activating lineage-specific transcriptional regulators. In osteoporosis, the reciprocal balance between the two differentiation pathways is altered, facilitating adipose accretion in bone marrow at the expense of osteoblast formation; suggesting that under this condition MSCs activity and their microenvironment may be disturbed. We summarize research on the properties of MSCs isolated from the bone marrow of control and osteoporotic post-menopausal women. Our observations indicate that intrinsic properties of MSCs are disturbed in osteoporosis. Moreover, we found that the regulatory conditions in the bone marrow fluid of control and osteoporotic patients are significantly different. These conclusions should be relevant for the use of MSCs in therapeutic applications.
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Affiliation(s)
- Ana María Pino
- Laboratorio de Biología Celular y Molecular, INTA, Universidad de Chile
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19
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Antisense targeting of TGF-beta1 augments BMP-induced upregulation of osteopontin, type I collagen and Cbfa1 in human Saos-2 cells. Exp Cell Res 2007; 313:1415-25. [PMID: 17359969 DOI: 10.1016/j.yexcr.2007.01.014] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2006] [Revised: 12/15/2006] [Accepted: 01/21/2007] [Indexed: 10/23/2022]
Abstract
Despite commonalities in signal transduction in osteoblasts from different species, the role of TGF-beta1 on bone formation remains elusive. In particular, the role of autocrine TGF-beta1 on human osteoblasts is largely unknown. Here we show the effect of TGF-beta1 knock-down on the proliferation and differentiation of osteoblasts induced by BMP2. Treatment with antisense TGF-beta1 moderately increased the rate of cell proliferation, which was completely reversed by the exogenous addition of TGF-beta1. Notably, TGF-beta1 blockade significantly enhanced BMP2-induced upregulation of mRNAs encoding osteopontin, type I collagen and Cbfa1, which was suppressed by exogenous TGF-beta1. Moreover, TGF-beta1 knock-down increased BMP2-induced phosphorylation of Smad1/5 as well as their nuclear import, which paralleled a reduction of inhibitory Smad6. These data suggest autocrine TGF-beta1 antagonizes BMP signaling through modulation of inducible Smad6 and the activity of BMP specific Smad1/5.
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20
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Baumert U, Golan I, Redlich M, Aknin JJ, Muessig D. Cleidocranial dysplasia: molecular genetic analysis and phenotypic-based description of a Middle European patient group. Am J Med Genet A 2006; 139A:78-85. [PMID: 16222673 DOI: 10.1002/ajmg.a.30927] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Cleidocranial dysplasia (CCD) (OMIM 119600) is a rare dysplasia of osseous and dental tissue. Characteristic features are typical facial and dental appearance plus morphologic anomalies. RUNX2 (OMIM 600211), the responsible gene for CCD, is considered to be a master gene for bone development and bone homeostasis. This study describes the genotype-phenotype correlation based on craniofacial features involving an interdisciplinary approach. Our patient cohort consisted of 31 CCD patients from 20 families; five patients from two families were unavailable for clinical examination. Since CCD mostly affects the craniofacial region, phenotypic characterization of each individual focused on craniofacial and dental aspects. After recording patient medical and family history, the phenotypic data was analyzed using homogeneity analysis (HOMALS), a statistical procedure for data reduction in categorical data analysis. The coding sequence of the RUNX2 gene was analyzed using PCR, direct sequencing, and restriction endonuclease digestion. Eight unpublished and four known heterozygous mutations in a total of 14/20 index patients (70%) were identified. In total, we detected 7 missense mutations, 5 frameshift mutations, and 2 nonsense mutations in 14 index patients (35%, 25%, 10%, respectively). The overall CCD phenotype varied from mild to fullblown expression. Using HOMALS, we were able to discriminate four groups of patients showing significant differences in phenotypic expressivity, thereby simplifying the grouping of our large patient cohort into clear distinguishable entities. Analysis of the mutation patterns revealed that mutational frequency and types of mutations found can be attributed to the gene's structure and function.
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Affiliation(s)
- Uwe Baumert
- Department of Orthodontics, Center for Craniofacial Genetics, University of Regensburg, Regensburg, Germany.
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21
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Abstract
TGF-beta1 is a ubiquitous growth factor that is implicated in the control of proliferation, migration, differentiation, and survival of many different cell types. It influences such diverse processes as embryogenesis, angiogenesis, inflammation, and wound healing. In skeletal tissue, TGF-beta1 plays a major role in development and maintenance, affecting both cartilage and bone metabolism, the latter being the subject of this review. Because it affects both cells of the osteoblast and osteoclast lineage, TGF-beta1 is one of the most important factors in the bone environment, helping to retain the balance between the dynamic processes of bone resorption and bone formation. Many seemingly contradictory reports have been published on the exact functioning of TGF-beta1 in the bone milieu. This review provides an overall picture of the bone-specific actions of TGF-beta1 and reconciles experimental discrepancies that have been reported for this multifunctional cytokine.
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Affiliation(s)
- Katrien Janssens
- Department of Medical Genetics, University of Antwerp, Campus Drie Eiken, 2610 Antwerp, Belgium
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22
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Stock M, Otto F. Control of RUNX2 isoform expression: The role of promoters and enhancers. J Cell Biochem 2005; 95:506-17. [PMID: 15838892 DOI: 10.1002/jcb.20471] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The three mammalian RUNX genes constitute the family of runt domain transcription factors that are involved in the regulation of a number of developmental processes such as haematopoiesis, osteogenesis and neuronal differentiation. All three genes show a complex temporo-spatial pattern of expression. Since the three proteins are probably mutually interchangeable with regard to function, most of the specificity of each family member seems to be based on a tightly controlled regulation of expression. While RUNX gene expression is driven by two promoters for each gene, the promoter sequence alone does not seem to suffice for a proper expressional control. This review focuses on the available evidence for the existence of such control mechanisms and studies aiming at discovering cis-acting regulatory sequences of the RUNX2 gene.
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Affiliation(s)
- Michael Stock
- Division of Hematology/Oncology, Medical Center, University of Freiburg, 79106 Freiburg, Germany
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Boumah CE, Selvamurugan N, Partridge NC. Transcription in the osteoblast: regulatory mechanisms utilized by parathyroid hormone and transforming growth factor-beta. PROGRESS IN NUCLEIC ACID RESEARCH AND MOLECULAR BIOLOGY 2005; 80:287-321. [PMID: 16164977 DOI: 10.1016/s0079-6603(05)80007-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Christine E Boumah
- Department of Physiology and Biophysics, University of Medicine and Dentistry of New Jersey-Robert Wood Johnson Medical School, Piscataway, New Jersey 08854, USA
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Li TF, O'Keefe RJ, Chen D. TGF-beta signaling in chondrocytes. FRONTIERS IN BIOSCIENCE : A JOURNAL AND VIRTUAL LIBRARY 2005; 10:681-8. [PMID: 15569609 PMCID: PMC2647990 DOI: 10.2741/1563] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Transforming growth factor-beta (TGF-beta) regulates a large variety of cellular activities. Binding of TGF- beta to its cell surface receptor triggers several signaling cascades, among which the TGF- beta -Smad pathway is the most extensively studied. TGF- beta also activates protein kinases, including MAPK, PKA and PKC, and modulates gene expression via its delicate interaction with other signaling pathways. During endochondral bone formation, TGF- beta acts as a potent inhibitor of the terminal differentiation of epiphyseal growth plate chondrocytes. This effect appears to be primarily mediated by Smad molecules, although MAPK-ATF2 signaling is also involved. The rate of chondrocyte maturation is tightly regulated through the interactions of Smad-mediated signaling, the Wnt signaling pathway, and the transcription factor Runx2. Improving our understanding of the exact mechanisms underlying TGF- beta -mediated signaling pathways and their effects may greatly impact the diagnosis and treatment of many common orthopaedic diseases.
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Affiliation(s)
- Tian-Fang Li
- Center for Musculoskeletal Research, Department of Orthopaedics, University of Rochester School of Medicine, Rochester, NY 14642, USA
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25
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Abstract
The RUNX are key regulators of lineage-specific gene expression in major developmental pathways. The expression of RUNX genes is tightly regulated, leading to a highly specific spatio/temporal expression pattern and to distinct phenotypes of gene knockouts. This review highlights the extensive structural similarities between the three mammalian RUNX genes and delineates how regulation of their expression at the levels of transcription and translation are orchestrated into the unique RUNX expression pattern.
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Affiliation(s)
- Ditsa Levanon
- Department of Molecular Genetics, The Weizmann Institute of Science, Rehovot 76100, Israel
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26
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Sowa H, Kaji H, Yamaguchi T, Sugimoto T, Chihara K. Activations of ERK1/2 and JNK by transforming growth factor beta negatively regulate Smad3-induced alkaline phosphatase activity and mineralization in mouse osteoblastic cells. J Biol Chem 2002; 277:36024-31. [PMID: 12130649 DOI: 10.1074/jbc.m206030200] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Transforming growth factor (TGF) beta inhibits alkaline phosphatase (ALP) activity and mineralization in mouse osteoblastic MC3T3-E1 cells, whereas local administration of TGF-beta stimulates bone formation in vivo. We recently demonstrated that Smad3, a TGF-beta signaling molecule, promotes ALP activity and mineralization in MC3T3-E1 cells. Moreover, the target disruption of Smad3 in mouse is reported to cause a decrease in bone mineral density. These findings indicate that Smad3 plays an important role in the regulation of bone formation. However, why the effects of TGF-beta and Smad3 on ALP activity and mineralization are different remains unknown. The purpose of the present study is to clarify the role of mitogen-activated protein kinase (MAPK) in TGF-beta and Smad3 pathways in osteoblast. TGF-beta activated extracellular signal-regulated kinases/p42/p44 (ERK1/2), p38 MAPK, and c-Jun N-terminal kinase (JNK) in mouse osteoblastic MC3T3-E1 cells. The expression of dominant negative type Smad3, Smad3DeltaC, affected neither TGF-beta-activated MAPKs nor TGF-beta-inhibited ALP activity. Specific inhibitors of ERK1/2 activation (PD98059 and U0126), as well as JNK inhibitors (curcumin and dicumarol) antagonized the inhibitory effects of TGF-beta on ALP activity and mineralization, whereas the specific inhibitor of p38 MAPK (SB203580) did not affect them. PD98059 and curcumin enhanced Smad3-induced ALP activity and mineralization, whereas SB203580 inhibited them. In the luciferase reporter assay using 3TP-lux with the specific Smad3-responsive element, PD98059, and curcumin enhanced TGF-beta- and Smad3-induced transcriptional activity in MC3T3-E1 cells. On the other hand, TGF-beta-induced production of type I collagen was antagonized by curcumin but not by PD98059. The present study indicated that TGF-beta-responsive ERK1/2 and JNK cascades negatively regulate Smad3-induced transcriptional activity as well as ALP activity and mineralization in osteoblasts.
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Affiliation(s)
- Hideaki Sowa
- Division of Endocrinology/Metabolism, Neurology and Hematology/Oncology, Department of Clinical Molecular Medicine, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-Cho, Chuo-ku, Kobe 650-0017, Japan
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Fukuchi M, Masuda N, Miyazaki T, Nakajima M, Osawa H, Kato H, Kuwano H. Decreased Smad4 expression in the transforming growth factor-beta signaling pathway during progression of esophageal squamous cell carcinoma. Cancer 2002; 95:737-43. [PMID: 12209716 DOI: 10.1002/cncr.10727] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND Transforming growth factor-beta (TGF-beta) has antiproliferative effects in various cells, and inactivation of the TGF-beta signaling pathway contributes to tumor progression or development. Smad4, a tumor suppressor gene, is a central mediator in the signaling pathways of the TGF-beta superfamily. This study was undertaken to clarify the correlation between Smad4 expression and the clinicopathologic characteristics of patients with esophageal squamous cell carcinoma (SCC). The authors also investigated the expression of components of the TGF-beta signaling pathway in seven established cell lines derived from esophageal SCC. METHODS Immunohistochemistry for Smad4 using monoclonal anti-Smad4 antibody was performed on surgical specimens obtained from 80 patients with esophageal SCC. In seven cell lines, the authors examined the expression of components of the TGF-beta signaling pathway using Western and Northern blot analyses. RESULTS There was a significant inverse correlation between Smad4 expression and both depth of invasion (P = 0.0008) and pathologic stage (P = 0.0079). The expression of Smad4 proteins could be detected in five of seven cell lines. The expression of TGF-beta type II receptor protein was decreased in two of seven cell lines, and the expression of both Smad2 and Smad3 proteins was decreased in only one cell line. The level of expression of Smad4 mRNA did not differ dramatically between cell lines and was not correlated with the quantity of Smad4 protein. CONCLUSIONS In this study, the expression of Smad4 protein appeared to be correlated with the depth of invasion of esophageal SCC. The loss of Smad4 expression was not regulated at the level of transcription.
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Affiliation(s)
- Minoru Fukuchi
- Department of Surgery, Gunma University Faculty of Medicine, Maebashi, Japan.
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28
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Kakonen SM, Selander KS, Chirgwin JM, Yin JJ, Burns S, Rankin WA, Grubbs BG, Dallas M, Cui Y, Guise TA. Transforming growth factor-beta stimulates parathyroid hormone-related protein and osteolytic metastases via Smad and mitogen-activated protein kinase signaling pathways. J Biol Chem 2002; 277:24571-8. [PMID: 11964407 DOI: 10.1074/jbc.m202561200] [Citation(s) in RCA: 229] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Transforming growth factor (TGF)-beta promotes breast cancer metastasis to bone. To determine whether the osteolytic factor parathyroid hormone-related protein (PTHrP) is the primary mediator of the tumor response to TGF-beta, mice were inoculated with MDA-MB-231 breast cancer cells expressing a constitutively active TGF-beta type I receptor. Treatment of the mice with a PTHrP-neutralizing antibody greatly decreased osteolytic bone metastases. There were fewer osteoclasts and significantly decreased tumor area in the antibody-treated mice. TGF-beta can signal through both Smad and mitogen-activated protein (MAP) kinase pathways. Stable transfection of wild-type Smad2, Smad3, or Smad4 increased TGF-beta-stimulated PTHrP secretion, whereas dominant-negative Smad2, Smad3, or Smad4 only partially reduced TGF-beta-stimulated PTHrP secretion. When the cells were treated with a variety of protein kinases inhibitors, only specific inhibitors of the p38 MAP kinase pathway significantly reduced both basal and TGF-beta-stimulated PTHrP production. The combination of Smad dominant-negative blockade and p38 MAP kinase inhibition resulted in complete inhibition of TGF-beta-stimulated PTHrP production. Furthermore, TGF-beta treatment of MDA-MB-231 cells resulted in a rapid phosphorylation of p38 MAP kinase. Thus, the p38 MAP kinase pathway appears to be a major component of Smad-independent signaling by TGF-beta and may provide a new molecular target for anti-osteolytic therapy.
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Affiliation(s)
- Sanna-Maria Kakonen
- Department of Molecular Medicine, University of Texas Health Science Center at San Antonio, Institute for Drug Development, Cancer Therapy and Research Center, San Antonio, Texas 78245-3217, USA
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29
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Sowa H, Kaji H, Yamaguchi T, Sugimoto T, Chihara K. Smad3 promotes alkaline phosphatase activity and mineralization of osteoblastic MC3T3-E1 cells. J Bone Miner Res 2002; 17:1190-9. [PMID: 12096832 DOI: 10.1359/jbmr.2002.17.7.1190] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Transforming growth factor (TGF) beta is abundantly stored in bone matrix and appears to regulate bone metabolism. Although the Smad family proteins are critical components of the TGF-beta signaling pathways, the roles of Smad3 in the expression of osteoblastic phenotypes remain poorly understood. Therefore, this study was performed to clarify the roles of Smad3 in the regulation of proliferation, expression of bone matrix proteins, and mineralization in osteoblasts by using mouse osteoblastic cell line MC3T3-E1 cells stably transfected with Smad3. Smad3 significantly inhibited [3H]thymidine incorporation and fluorescent intensity of the MTT-dye assay, compared with empty vector. Moreover, Smad3 increased the levels of type I procollagen, osteopontin (OPN), and matrix Gla protein (MGP) mRNA in Northern blotting. These effects of Smad3 mimicked the effects of TGF-beta on the same cells. On the other hand, Smad3 greatly enhanced ALP activity and mineralization of MC3T3-E1 cells compared with empty vector, although TGF-beta inhibited ALP activity and mineralization of wild-type MC3T3-E1 cells. A type I collagen synthesis inhibitor L-azetidine-2-carboxylic acid, as well as osteocalcin (OCN), significantly antagonized Smad3-stimulated ALP activity and mineralization of MC3T3-E1 cells. In conclusion, this study showed that in mouse osteoblastic cells, Smad3 inhibited proliferation, but it also enhanced ALP activity, mineralization, and the levels of bone matrix proteins such as type I collagen (COLI), OPN, and MGP. We propose that Smad3 plays an important role in osteoblastic bone formation and might help to elucidate the transcriptional mechanism of bone formation and possibly lead to the development of bone-forming drugs.
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Affiliation(s)
- Hideaki Sowa
- Third Department of Medicine, Kobe University School of Medicine, Japan
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30
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Affiliation(s)
- M M Cohen
- Department of Oral and Maxillofacial Sciences, Dalhousie University, Halifax, Nova Scotia, Canada B3H 3J5.
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31
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Affiliation(s)
- O Eickelberg
- Yale University School of Medicine, Department of Pathology, 310 Cedar Street, New Haven, CT 06520-9023, USA.
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32
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Ji C, Eickelberg O, McCarthy TL, Centrella M. Control and counter-control of TGF-beta activity through FAST and Runx (CBFa) transcriptional elements in osteoblasts. Endocrinology 2001; 142:3873-9. [PMID: 11517165 DOI: 10.1210/endo.142.9.8399] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
FAST and Runx (CBFa) transcription factors, which are expressed during specific phases of embryogenesis and tissue patterning, bind directly to Smad proteins and integrate effects induced by various TGF-beta gene family members. The DNA binding sequences for FAST and Runx differ only minimally. The isoform Runx2 (previously termed CBFa1) is highly expressed by osteoblasts and regulates expression of the TGF-beta receptor I in these cells. Here we show that FAST-dependent transcription is endogenously restricted in osteoblasts but can be significantly enhanced by disruption of Runx2 expression. Native and synthetic Runx2 bind to both Runx and FAST binding sequences, whereas FAST-1 efficiently binds only to the FAST binding sequence. However, overexpression of FAST-1 potently suppresses TGF-beta receptor I gene expression in osteoblasts and thereby reduces TGF-beta activity independently of competing for Runx2 at the level of DNA binding. These results provide a new example of how nuclear factors associated with specific developmental states or tissue lineages may influence TGF-beta-dependent events in restricted ways.
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Affiliation(s)
- C Ji
- Department of Surgery, Plastic Surgery Section, Yale University School of Medicine, New Haven, Connecticut 06520, USA
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33
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Ueno A, Kitase Y, Moriyama K, Inoue H. MC3T3-E1-conditioned medium-induced mineralization by clonal rat dental pulp cells. Matrix Biol 2001; 20:347-55. [PMID: 11566269 DOI: 10.1016/s0945-053x(01)00141-x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Dental pulp is thought to participate in supplementary mineralization, such as reparative dentin and pulp stones, but no direct proof of this has been reported. To study this process at a molecular level, we investigated the matrix mineralization of dental pulp using a clonal cell line (RPC-C2A) derived from rat incisor dental pulp. Mineralized nodules in extracellular matrix were formed by RPC-C2A cells cultured in the presence of conditioned medium (CM) from confluent osteoblastic MC3T3-E1 cells. These nodules were stained by the von Kossa method and with alizarin red S and quantified by the measurement of acid-soluble calcium deposition. This CM was most effective when collected 3-6 days after confluency and added at 50% to the culture medium. The CM-treated RPC-C2A cells showed high alkaline phosphatase activity, a high mRNA level of osteocalcin and decreases in the mRNA levels of osteopontin and osteonectin, but undetectable levels of mRNA of dentin sialophosphoprotein by Northern blot analyses. A pan-specific anti-transforming growth factor (TGF)-beta antibody and a soluble form of receptor for bone morphogenetic protein (BMP)-2/-4 did not neutralize the CM-induced mineralization. These results suggest that some soluble factor(s) other than TGF-beta or BMP-2/-4 in the CM from MC3T3-E1 cells cause differentiation of RPC-C2A cells to osteoblast-like cells.
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Affiliation(s)
- A Ueno
- Department of Biochemistry, School of Dentistry, The University of Tokushima, 3-18-15 Kuramoto-cho, Tokushima 770-8504, Japan.
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Ito Y, Sarkar P, Mi Q, Wu N, Bringas P, Liu Y, Reddy S, Maxson R, Deng C, Chai Y. Overexpression of Smad2 reveals its concerted action with Smad4 in regulating TGF-beta-mediated epidermal homeostasis. Dev Biol 2001; 236:181-94. [PMID: 11456453 DOI: 10.1006/dbio.2001.0332] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Members of the transforming growth factor-beta (TGF-beta) superfamily are critical regulators for epithelial growth and can alter the differentiation of keratinocytes. Transduction of TGF-beta signaling depends on the phosphorylation and activation of Smad proteins by heteromeric complexes of ligand-specific type I and II receptors. To understand the function of TGF-beta and activin-specific Smad, we generated transgenic mice that overexpress Smad2 in epidermis under the control of keratin 14 promoter. Overexpression of Smad2 increases endogenous Smad4 and TGF-beta 1 expression while heterozygous loss of Smad2 reduces their expression levels, suggesting a concerted action of Smad2 and -4 in regulating TGF-beta signaling during skin development. These transgenic mice have delayed hair growth, underdeveloped ears, and shorter tails. In their skin, there is severe thickening of the epidermis with disorganized epidermal architecture, indistinguishable basement membrane, and dermal fibrosis. These abnormal phenotypes are due to increased proliferation of the basal epidermal cells and abnormalities in the program of keratinocyte differentiation. The ectodermally derived enamel structure is also abnormal. Collectively, our study presents the first in vivo evidence that, by providing an auto-feedback in TGF-beta signaling, Smad2 plays a pivotal role in regulating TGF-beta-mediated epidermal homeostasis.
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Affiliation(s)
- Y Ito
- Center for Craniofacial Molecular Biology, School of Dentistry, University of Southern California, 2250 Alcazar Street, CSA 103, Los Angeles, California 90033, USA
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35
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Rosendahl A, Checchin D, Fehniger TE, ten Dijke P, Heldin CH, Sideras P. Activation of the TGF-beta/activin-Smad2 pathway during allergic airway inflammation. Am J Respir Cell Mol Biol 2001; 25:60-8. [PMID: 11472976 DOI: 10.1165/ajrcmb.25.1.4396] [Citation(s) in RCA: 102] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Changes in the levels of transforming growth factor (TGF)-beta cytokines or receptors observed during the progression of several inflammatory and fibrotic disorders have been used to implicate these cytokines in the pathophysiology of these diseases. Although correlative, these studies were inconclusive because they were unable to demonstrate actual continuous TGF-beta-mediated signaling in the involved tissues. We reasoned that the phosphorylation state and subcellular localization of Smad2, the intracellular effector of TGF-beta/activin-mediated signaling, could be used as a marker of active signaling mediated by these cytokines in situ. We therefore used an experimental model of ovalbumin-induced allergic airway inflammation and were able to demonstrate a dramatic increase in the numbers of bronchial epithelial, alveolar, and infiltrating inflammatory cells expressing nuclear phosphorylated Smad2 within the allergen-challenged lungs. This was accompanied by strong upregulation of the activin receptor ALK-4/ActR-IB and redistribution of the TGF-beta responsive ALK-5/TbetaR-I. Although levels of TGF-beta1, TGF-beta2, and TGF-beta3 messenger RNA (mRNA) were marginally altered, the level of activin mRNA was strongly upregulated during the inflammatory response. Our data illustrate the usefulness of antiphosphorylated Smad antibodies in demonstrating active TGF- beta/activin-mediated signaling in vivo and strongly suggest that activin/Smad-mediated signaling could be a critical contributor in the pathophysiology of allergic pulmonary diseases.
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Affiliation(s)
- A Rosendahl
- Department of Molecular Sciences and Biosciences, AstraZeneca R&D Lund, Scheelevägen 2, S-221 87 Lund, Sweden.
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36
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Alliston T, Choy L, Ducy P, Karsenty G, Derynck R. TGF-beta-induced repression of CBFA1 by Smad3 decreases cbfa1 and osteocalcin expression and inhibits osteoblast differentiation. EMBO J 2001; 20:2254-72. [PMID: 11331591 PMCID: PMC125448 DOI: 10.1093/emboj/20.9.2254] [Citation(s) in RCA: 405] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Transforming growth factor-beta (TGF-beta), a secreted factor present at high levels in bone, inhibits osteoblast differentiation in culture; yet, the mechanism of this inhibition remains unclear. We studied the effects of TGF-beta and its effectors, the Smads, on the expression and function of the osteoblast transcription factor CBFA1. TGF-beta inhibited the expression of the cbfa1 and osteocalcin genes, whose expression is controlled by CBFA1 in osteoblast-like cell lines. This inhibition was mediated by Smad3, which interacts physically with CBFA1 and represses its transcriptional activity at the CBFA1-binding OSE2 promoter sequence. The repression of CBFA1 function by Smad3 contrasts with previous observations that Smads function as transcription activators. This repression occurred in mesenchymal but not epithelial cells, and depended on the promoter sequence. Smad3-mediated repression of CBFA1 provides a central regulatory mechanism for the inhibition of osteoblast differentiation by TGF-beta, since it inhibits both cbfa1 transcription and transcriptional activation of osteoblast differentiation genes by CBFA1. Altering Smad3 signaling influenced osteoblast differentiation in the presence or absence of TGF-beta, implicating Smad3/TGF-beta-mediated repression in autocrine regulation of osteoblast differentiation.
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Affiliation(s)
- T Alliston
- Department of Growth and Development, Program in Cell Biology, University of California at San Francisco, San Francisco, CA 94143-0640, USA
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37
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Abstract
Members of the transforming growth factor-beta (TGF-beta) family bind to type II and type I serine/threonine kinase receptors, which initiate intracellular signals through activation of Smad proteins. Receptor-regulated Smads (R-Smads) are anchored to the cell membrane by interaction with membrane-bound proteins, including Smad anchor for receptor activation (SARA). Upon ligand stimulation, R-Smads are phosphorylated by the receptors and form oligomeric complexes with common-partner Smads (Co-Smads). The oligomeric Smad complexes then translocate into the nucleus, where they regulate the transcription of target genes by direct binding to DNA, interaction with various DNA-binding proteins, and recruitment of transcriptional coactivators or corepressors. A third class of Smads, inhibitory Smads (I-Smads), inhibits the signals from the serine/threonine kinase receptors. Since the expression of I-Smads is induced by the TGF-beta superfamily proteins, Smads constitute an autoinhibitory signaling pathway. The functions of Smads are regulated by other signaling pathways, such as the MAP kinase pathway. Moreover, Smads interact with and modulate the functions of various transcription factors which are downstream targets of other signaling pathways. Loss of function of certain Smads is involved in tumorigenesis, e.g., pancreatic and colorectal cancers. Analyses by gene targeting revealed pivotal roles of Smads in early embryogenesis, angiogenesis, and immune functions in vivo.
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Affiliation(s)
- K Miyazono
- Department of Biochemistry, Cancer Institute of Japanese Foundation for Cancer Research, Tokyo, Japan
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38
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Huang G, Shigesada K, Ito K, Wee HJ, Yokomizo T, Ito Y. Dimerization with PEBP2beta protects RUNX1/AML1 from ubiquitin-proteasome-mediated degradation. EMBO J 2001; 20:723-33. [PMID: 11179217 PMCID: PMC145428 DOI: 10.1093/emboj/20.4.723] [Citation(s) in RCA: 227] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The RUNX family genes are the mammalian homologs of the Drosophila genes runt and lozenge, and members of this family function as master regulators of definitive hematopoiesis and osteogenesis. The RUNX genes encode the alpha subunit of the transcription factor PEBP2/CBF. The beta subunit consists of the non-RUNX protein PEBP2beta. We found that RUNX1/AML1, which is essential for hematopoiesis, is continuously subjected to proteolytic degradation mediated by the ubiquitin-proteasome pathway. When PEBP2beta is present, however, the ubiquitylation of RUNX1 is abrogated and this causes a dramatic inhibition of RUNX1 proteolysis. Heterodimerization between PEBP2beta and RUNX1 thus appears to be an essential step in the generation of transcriptionally competent RUNX1. Consistent with this notion, RUNX1 was barely detected in PEBP2beta(-/-) mouse. CBF(PEBP2)beta- SMMHC, the chimeric protein associated with inv(16) acute myeloid leukemia, was found to protect RUNX1 from proteolytic degradation more efficiently than PEBP2beta. These results reveal a hitherto unknown and major role of PEBP2beta, namely that it regulates RUNX1 by controlling its turnover. This has allowed us to gain new insights into the mechanism of leukemogenesis by CBFbeta-SMMHC.
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Affiliation(s)
| | - Katsuya Shigesada
- Laboratory of Cell Regulation, Department of Viral Oncology, and
Molecular Genetics, Institute for Virus Research, Kyoto University, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan Corresponding author e-mail:
| | | | | | | | - Yoshiaki Ito
- Laboratory of Cell Regulation, Department of Viral Oncology, and
Molecular Genetics, Institute for Virus Research, Kyoto University, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan Corresponding author e-mail:
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Lee KS, Kim HJ, Li QL, Chi XZ, Ueta C, Komori T, Wozney JM, Kim EG, Choi JY, Ryoo HM, Bae SC. Runx2 is a common target of transforming growth factor beta1 and bone morphogenetic protein 2, and cooperation between Runx2 and Smad5 induces osteoblast-specific gene expression in the pluripotent mesenchymal precursor cell line C2C12. Mol Cell Biol 2000; 20:8783-92. [PMID: 11073979 PMCID: PMC86511 DOI: 10.1128/mcb.20.23.8783-8792.2000] [Citation(s) in RCA: 688] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2000] [Accepted: 09/08/2000] [Indexed: 01/01/2023] Open
Abstract
When C2C12 pluripotent mesenchymal precursor cells are treated with transforming growth factor beta1 (TGF-beta1), terminal differentiation into myotubes is blocked. Treatment with bone morphogenetic protein 2 (BMP-2) not only blocks myogenic differentiation of C2C12 cells but also induces osteoblast differentiation. The molecular mechanisms governing the ability of TGF-beta1 and BMP-2 to both induce ligand-specific responses and inhibit myogenic differentiation are not known. We identified Runx2/PEBP2alphaA/Cbfa1, a global regulator of osteogenesis, as a major TGF-beta1-responsive element binding protein induced by TGF-beta1 and BMP-2 in C2C12 cells. Consistent with the observation that Runx2 can be induced by either TGF-beta1 or BMP-2, the exogenous expression of Runx2 mediated some of the effects of TGF-beta1 and BMP-2 but not osteoblast-specific gene expression. Runx2 mimicked common effects of TGF-beta1 and BMP-2 by inducing expression of matrix gene products (for example, collagen and fibronectin), suppressing MyoD expression, and inhibiting myotube formation of C2C12 cells. For osteoblast differentiation, an additional effector, BMP-specific Smad protein, was required. Our results indicate that Runx2 is a major target gene shared by TGF-beta and BMP signaling pathways and that the coordinated action of Runx2 and BMP-activated Smads leads to the induction of osteoblast-specific gene expression in C2C12 cells.
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Affiliation(s)
- K S Lee
- Department of Biochemistry, School of Medicine, and Medical Research Institute, Chungbuk National University, Cheongju 361-763, Korea
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40
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Weinstein M, Yang X, Deng C. Functions of mammalian Smad genes as revealed by targeted gene disruption in mice. Cytokine Growth Factor Rev 2000; 11:49-58. [PMID: 10708952 DOI: 10.1016/s1359-6101(99)00028-3] [Citation(s) in RCA: 140] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The Smad genes are the intracellular mediators of TGF-beta signals. Targeted mutagenesis in mice has yielded valuable new insights into the functions of this important gene family. These experiments have shown that Smad2 and Smad4 are needed for gastrulation, Smad5 for angiogenesis, and Smad3 for establishment of the mucosal immune response and proper development of the skeleton. In addition, these experiments have shown us the importance of gene dosage in this family, as several of its members yielded haploinsufficiency phenotypes. These include gastrulation and craniofacial defects for Smad2, accelerated wound healing for Smad3, and the incidence of gastric cancer for Smad4. Combinatorial genetics has also revealed functions of Smads in left/right isomerism and liver development.
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Affiliation(s)
- M Weinstein
- Genetics of Development and Disease Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, 10/9N105, 10 Center Drive, Bethesda, MD 20892, USA
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Selvamurugan N, Pulumati MR, Tyson DR, Partridge NC. Parathyroid hormone regulation of the rat collagenase-3 promoter by protein kinase A-dependent transactivation of core binding factor alpha1. J Biol Chem 2000; 275:5037-42. [PMID: 10671545 DOI: 10.1074/jbc.275.7.5037] [Citation(s) in RCA: 160] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Previously we showed that the activator protein-1 site and the runt domain binding site in the collagenase-3 promoter act cooperatively in response to parathyroid hormone (PTH) in the rat osteoblastic osteosarcoma cell line, UMR 106-01. Our results of the expression pattern of core binding factor alpha1 (Cbfa1), which binds to the runt domain site, indicated that there is no change in the levels of Cbfa1 protein or RNA under either control conditions or after PTH treatment. The importance of posttranslational modification of Cbfa1 in the signaling pathway for PTH-induced collagenase-3 promoter activity was analyzed. PTH stimulation of collagenase-3 promoter activity was completely abrogated by protein kinase A (PKA) inhibition. To determine the role of PKA activity with respect to Cbfa1 activation (in addition to its known activity of phosphorylating cAMP-response element-binding protein to enhance c-fos promoter activity), we utilized the heterologous Gal4 transcription system. PTH stimulated the transactivation of activation domain-3 in Cbfa1 through the PKA site. In vitro phosphorylation studies indicated that the PKA site in the wild type activation domain-3 is a substrate for phosphorylation by PKA. Thus, we demonstrate that PTH induces a PKA-dependent transactivation of Cbfa1, and this transactivation is required for collagenase-3 promoter activity in UMR cells.
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Affiliation(s)
- N Selvamurugan
- Department of Pharmacological and Physiological Science, St. Louis University School of Medicine, St. Louis, Missouri 63104, USA
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