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Adolphe C, Millar A, Kojic M, Barkauskas DS, Sundström A, Swartling FJ, Hediyeh-Zadeh S, Tan CW, Davis MJ, Genovesi LA, Wainwright BJ. SOX9 Defines Distinct Populations of Cells in SHH Medulloblastoma but Is Not Required for Math1-Driven Tumor Formation. Mol Cancer Res 2021; 19:1831-1839. [PMID: 34330843 DOI: 10.1158/1541-7786.mcr-21-0117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 05/18/2021] [Accepted: 07/19/2021] [Indexed: 11/16/2022]
Abstract
Medulloblastoma is the most common malignant pediatric brain tumor and there is an urgent need for molecularly targeted and subgroup-specific therapies. The stem cell factor SOX9, has been proposed as a potential therapeutic target for the treatment of Sonic Hedgehog medulloblastoma (SHH-MB) subgroup tumors, given its role as a downstream target of Hedgehog signaling and in functionally promoting SHH-MB metastasis and treatment resistance. However, the functional requirement for SOX9 in the genesis of medulloblastoma remains to be determined. Here we report a previously undocumented level of SOX9 expression exclusively in proliferating granule cell precursors (GCP) of the postnatal mouse cerebellum, which function as the medulloblastoma-initiating cells of SHH-MBs. Wild-type GCPs express comparatively lower levels of SOX9 than neural stem cells and mature astroglia and SOX9low GCP-like tumor cells constitute the bulk of both infant (Math1Cre:Ptch1lox/lox ) and adult (Ptch1LacZ/+ ) SHH-MB mouse models. Human medulloblastoma single-cell RNA data analyses reveal three distinct SOX9 populations present in SHH-MB and noticeably absent in other medulloblastoma subgroups: SOX9 + MATH1 + (GCP), SOX9 + GFAP + (astrocytes) and SOX9 + MATH1 + GFAP + (potential tumor-derived astrocytes). To functionally address whether SOX9 is required as a downstream effector of Hedgehog signaling in medulloblastoma tumor cells, we ablated Sox9 using a Math1Cre model system. Surprisingly, targeted ablation of Sox9 in GCPs (Math1Cre:Sox9lox/lox ) revealed no overt phenotype and loss of Sox9 in SHH-MB (Math1Cre:Ptch1lox/lox;Sox9lox/lox ) does not affect tumor formation. IMPLICATIONS: Despite preclinical data indicating SOX9 plays a key role in SHH-MB biology, our data argue against SOX9 as a viable therapeutic target.
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Affiliation(s)
- Christelle Adolphe
- The University of Queensland Diamantina Institute, University of Queensland, Woolloongabba, Queensland, Australia
| | - Amanda Millar
- The University of Queensland Diamantina Institute, University of Queensland, Woolloongabba, Queensland, Australia
| | - Marija Kojic
- The University of Queensland Diamantina Institute, University of Queensland, Woolloongabba, Queensland, Australia
| | - Deborah S Barkauskas
- Institute for Molecular Bioscience, University of Queensland, Brisbane, Queensland, Australia
| | - Anders Sundström
- Department of Immunology, Genetics, and Pathology, Science For Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Fredrik J Swartling
- Department of Immunology, Genetics, and Pathology, Science For Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Soroor Hediyeh-Zadeh
- Bioinformatics Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia.,Department of Medical Biology, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Victoria, Australia
| | - Chin Wee Tan
- Bioinformatics Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia.,Department of Medical Biology, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Victoria, Australia
| | - Melissa J Davis
- Bioinformatics Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia.,Department of Medical Biology, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Victoria, Australia.,Department of Clinical Pathology, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Victoria, Australia
| | - Laura A Genovesi
- The University of Queensland Diamantina Institute, University of Queensland, Woolloongabba, Queensland, Australia
| | - Brandon J Wainwright
- The University of Queensland Diamantina Institute, University of Queensland, Woolloongabba, Queensland, Australia.
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Genovesi L, Millar A, Tolson E, Singleton M, Hassall E, Kojic M, Brighi C, Girald E, Andradas C, Kuchibhotla M, Endersby R, Gottardo N, Bernard A, Adolphe C, Olson J, Davis M, Wainwright B. MOMC-5. Systems pharmacogenomics identifies novel targets and clinically actionable therapeutics for medulloblastoma. Neurooncol Adv 2021. [PMCID: PMC8255431 DOI: 10.1093/noajnl/vdab070.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Background Medulloblastoma (MB) is the most common malignant paediatric brain tumour and a leading cause of cancer-related mortality and morbidity. Existing treatment protocols are aggressive in nature resulting in significant neurological, intellectual and physical disabilities for the children undergoing treatment. Clearly, there is an urgent need for improved, targeted therapies that minimize these harmful side effects. Methods We identified candidate drugs for MB using a network-based systems-pharmacogenomics approach: based on results from a functional genomics screen, we identified a network of interactions implicated in human MB growth regulation. We then integrated drugs and their known mechanisms of action, along with gene expression data from a large collection of medulloblastoma patients to identify drugs with potential to treat MB. Results Our analyses identified drugs targeting CDK4, CDK6, and AURKA as strong candidates for MB; all of these genes are well validated as drug targets in other tumour types. We also identified non-WNT MB as a novel indication for drugs targeting TUBB, CAD, SNRPA, SLC1A5, PTPRS, P4HB and CHEK2. Based upon these analyses we subsequently demonstrated that one of these drugs, the new microtubule stabilizing agent, ixabepilone, blocked tumour growth in vivo in mice bearing Sonic Hedgehog and Group 3 patient-derived xenograft tumours, providing the first demonstration of its efficacy in MB. Conclusions Our findings confirm that this data-driven systems pharmacogenomics strategy is a powerful approach for the discovery and validation of novel therapeutic candidates relevant to MB treatment, and along with data validating ixabepilone in PDX models of the two most aggressive subtypes of medulloblastoma, we present the network analysis framework as a resource for the field.
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Affiliation(s)
- Laura Genovesi
- The University of Queensland Diamantina Institute, Woolloongabba, QLD, Australia
| | - Amanda Millar
- The University of Queensland Diamantina Institute, Woolloongabba, QLD, Australia
| | - Elissa Tolson
- The University of Queensland Diamantina Institute, Woolloongabba, QLD, Australia
| | - Matthew Singleton
- The University of Queensland Diamantina Institute, Woolloongabba, QLD, Australia
| | - Emily Hassall
- The University of Queensland Diamantina Institute, Woolloongabba, QLD, Australia
| | - Marija Kojic
- The University of Queensland Diamantina Institute, Woolloongabba, QLD, Australia
| | - Caterina Brighi
- Australian Institute for Bioengineering and Nanotechnology, St Lucia, QLD, Australia
| | - Emily Girald
- Fred Hutchinson Cancer Research Center, Seattle, Washington, DC, USA
| | | | | | | | | | - Anne Bernard
- QFAB Bioinformatics, Institute for Molecular Bioscience, St Lucia, QLD, Australia
| | - Christelle Adolphe
- The University of Queensland Diamantina Institute, Woolloongabba, QLD, Australia
| | - James Olson
- Fred Hutchinson Cancer Research Center, Seattle, Washington, DC, USA
| | - Melissa Davis
- The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, USA
| | - Brandon Wainwright
- The University of Queensland Diamantina Institute, Woolloongabba, QLD, USA
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3
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Genovesi LA, Millar A, Tolson E, Singleton M, Hassall E, Kojic M, Brighi C, Girard E, Andradas C, Kuchibhotla M, Bhuva DD, Endersby R, Gottardo NG, Bernard A, Adolphe C, Olson JM, Taylor MD, Davis MJ, Wainwright BJ. Systems pharmacogenomics identifies novel targets and clinically actionable therapeutics for medulloblastoma. Genome Med 2021; 13:103. [PMID: 34154646 PMCID: PMC8215804 DOI: 10.1186/s13073-021-00920-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Accepted: 06/04/2021] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Medulloblastoma (MB) is the most common malignant paediatric brain tumour and a leading cause of cancer-related mortality and morbidity. Existing treatment protocols are aggressive in nature resulting in significant neurological, intellectual and physical disabilities for the children undergoing treatment. Thus, there is an urgent need for improved, targeted therapies that minimize these harmful side effects. METHODS We identified candidate drugs for MB using a network-based systems-pharmacogenomics approach: based on results from a functional genomics screen, we identified a network of interactions implicated in human MB growth regulation. We then integrated drugs and their known mechanisms of action, along with gene expression data from a large collection of medulloblastoma patients to identify drugs with potential to treat MB. RESULTS Our analyses identified drugs targeting CDK4, CDK6 and AURKA as strong candidates for MB; all of these genes are well validated as drug targets in other tumour types. We also identified non-WNT MB as a novel indication for drugs targeting TUBB, CAD, SNRPA, SLC1A5, PTPRS, P4HB and CHEK2. Based upon these analyses, we subsequently demonstrated that one of these drugs, the new microtubule stabilizing agent, ixabepilone, blocked tumour growth in vivo in mice bearing patient-derived xenograft tumours of the Sonic Hedgehog and Group 3 subtype, providing the first demonstration of its efficacy in MB. CONCLUSIONS Our findings confirm that this data-driven systems pharmacogenomics strategy is a powerful approach for the discovery and validation of novel therapeutic candidates relevant to MB treatment, and along with data validating ixabepilone in PDX models of the two most aggressive subtypes of medulloblastoma, we present the network analysis framework as a resource for the field.
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Affiliation(s)
- Laura A Genovesi
- The University of Queensland Diamantina Institute, The University of Queensland, Woolloongabba, QLD, 4102, Australia
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Amanda Millar
- The University of Queensland Diamantina Institute, The University of Queensland, Woolloongabba, QLD, 4102, Australia
| | - Elissa Tolson
- The University of Queensland Diamantina Institute, The University of Queensland, Woolloongabba, QLD, 4102, Australia
| | - Matthew Singleton
- The University of Queensland Diamantina Institute, The University of Queensland, Woolloongabba, QLD, 4102, Australia
| | - Emily Hassall
- The University of Queensland Diamantina Institute, The University of Queensland, Woolloongabba, QLD, 4102, Australia
| | - Marija Kojic
- The University of Queensland Diamantina Institute, The University of Queensland, Woolloongabba, QLD, 4102, Australia
| | - Caterina Brighi
- ARC Centre of Excellence for Convergent Bio-Nano Science and Technology, The University of Queensland, St Lucia, QLD, 4072, Australia
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Emily Girard
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA, 98109, USA
| | - Clara Andradas
- Brain Tumour Research Program, Telethon Kids Cancer Centre, Telethon Kids Institute, Nedlands, WA, 6009, Australia
| | - Mani Kuchibhotla
- Brain Tumour Research Program, Telethon Kids Cancer Centre, Telethon Kids Institute, Nedlands, WA, 6009, Australia
| | - Dharmesh D Bhuva
- Bioinformatics Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, 3052, Australia
- Department of Medical Biology, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Melbourne, Victoria, 3010, Australia
| | - Raelene Endersby
- Brain Tumour Research Program, Telethon Kids Cancer Centre, Telethon Kids Institute, Nedlands, WA, 6009, Australia
| | - Nicholas G Gottardo
- Brain Tumour Research Program, Telethon Kids Cancer Centre, Telethon Kids Institute, Nedlands, WA, 6009, Australia
| | - Anne Bernard
- QFAB Bioinformatics, Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Christelle Adolphe
- The University of Queensland Diamantina Institute, The University of Queensland, Woolloongabba, QLD, 4102, Australia
| | - James M Olson
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA, 98109, USA
| | - Michael D Taylor
- Programme in Developmental and Stem Cell Biology, Arthur and Sonia Labatt Brain Tumour Research Centre, Hospital for Sick Children, Toronto, Ontario, MSG 1X8, Canada
- Division of Neurosurgery, Hospital for Sick Children, Toronto, Ontario, MSG 1X8, Canada
| | - Melissa J Davis
- Bioinformatics Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, 3052, Australia.
- Department of Medical Biology, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Melbourne, Victoria, 3010, Australia.
- Department of Clinical Pathology, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Melbourne, Victoria, 3010, Australia.
| | - Brandon J Wainwright
- The University of Queensland Diamantina Institute, The University of Queensland, Woolloongabba, QLD, 4102, Australia.
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, QLD, 4072, Australia.
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4
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Genovesi LA, Puttick S, Millar A, Kojic M, Ji P, Lagendijk AK, Brighi C, Bonder CS, Adolphe C, Wainwright BJ. Patient-derived orthotopic xenograft models of medulloblastoma lack a functional blood-brain barrier. Neuro Oncol 2021; 23:732-742. [PMID: 33258962 DOI: 10.1093/neuonc/noaa266] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Novel targeted therapies for children diagnosed with medulloblastoma (MB), the most common malignant pediatric brain tumor, are urgently required. A major hurdle in the development of effective therapies is the impaired delivery of systemic therapies to tumor cells due to a specialized endothelial blood-brain barrier (BBB). Accordingly, the integrity of the BBB is an essential consideration in any preclinical model used for assessing novel therapeutics. This study sought to assess the functional integrity of the BBB in several preclinical mouse models of MB. METHODS Dynamic contrast enhancement magnetic resonance imaging (MRI) was used to evaluate blood-brain-tumor barrier (BBTB) permeability in a murine genetically engineered mouse model (GEMM) of Sonic Hedgehog (SHH) MB, patient-derived orthotopic xenograft models of MB (SHH and Gp3), and orthotopic transplantation of GEMM tumor cells, enabling a comparison of the direct effects of transplantation on the integrity of the BBTB. Immunofluorescence analysis was performed to compare the structural and subcellular features of tumor-associated vasculature in all models. RESULTS Contrast enhancement was observed in all transplantation models of MB. No contrast enhancement was observed in the GEMM despite significant tumor burden. Cellular analysis of BBTB integrity revealed aberrancies in all transplantation models, correlating to the varying levels of BBTB permeability observed by MRI in these models. CONCLUSIONS These results highlight functional differences in the integrity of the BBTB and tumor vessel phenotype between commonly utilized preclinical models of MB, with important implications for the preclinical evaluation of novel therapeutic agents for MB.
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Affiliation(s)
- Laura A Genovesi
- The University of Queensland Diamantina Institute, Translational Research Institute, The University of Queensland, Woolloongabba, Queensland, Australia.,Institute for Molecular Bioscience, The University of Queensland, St Lucia, Queensland, Australia
| | - Simon Puttick
- Probing Biosystems Future Science Platform, Commonwealth Scientific and Industrial Research Organization, Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia
| | - Amanda Millar
- The University of Queensland Diamantina Institute, Translational Research Institute, The University of Queensland, Woolloongabba, Queensland, Australia
| | - Marija Kojic
- The University of Queensland Diamantina Institute, Translational Research Institute, The University of Queensland, Woolloongabba, Queensland, Australia
| | - Pengxiang Ji
- The University of Queensland Diamantina Institute, Translational Research Institute, The University of Queensland, Woolloongabba, Queensland, Australia
| | - Anne K Lagendijk
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, Queensland, Australia
| | - Caterina Brighi
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St Lucia, Queensland, Australia.,ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, The University of Queensland, St Lucia, Queensland, Australia
| | - Claudine S Bonder
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, South Australia, Australia.,Adelaide Medical School, Faculty of Health Sciences, University of Adelaide, Adelaide, South Australia, Australia
| | - Christelle Adolphe
- The University of Queensland Diamantina Institute, Translational Research Institute, The University of Queensland, Woolloongabba, Queensland, Australia
| | - Brandon J Wainwright
- The University of Queensland Diamantina Institute, Translational Research Institute, The University of Queensland, Woolloongabba, Queensland, Australia.,Institute for Molecular Bioscience, The University of Queensland, St Lucia, Queensland, Australia
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5
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Starobova H, Monteleone M, Adolphe C, Batoon L, Sandrock CJ, Tay B, Deuis JR, Smith AV, Mueller A, Nadar EI, Lawrence GP, Mayor A, Tolson E, Levesque JP, Pettit AR, Wainwright BJ, Schroder K, Vetter I. Vincristine-induced peripheral neuropathy is driven by canonical NLRP3 activation and IL-1β release. J Exp Med 2021; 218:e20201452. [PMID: 33656514 PMCID: PMC7933984 DOI: 10.1084/jem.20201452] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 12/09/2020] [Accepted: 01/19/2021] [Indexed: 12/29/2022] Open
Abstract
Vincristine is an important component of many regimens used for pediatric and adult malignancies, but it causes a dose-limiting sensorimotor neuropathy for which there is no effective treatment. This study aimed to delineate the neuro-inflammatory mechanisms contributing to the development of mechanical allodynia and gait disturbances in a murine model of vincristine-induced neuropathy, as well as to identify novel treatment approaches. Here, we show that vincristine-induced peripheral neuropathy is driven by activation of the NLRP3 inflammasome and subsequent release of interleukin-1β from macrophages, with mechanical allodynia and gait disturbances significantly reduced in knockout mice lacking NLRP3 signaling pathway components, or after treatment with the NLRP3 inhibitor MCC950. Moreover, treatment with the IL-1 receptor antagonist anakinra prevented the development of vincristine-induced neuropathy without adversely affecting chemotherapy efficacy or tumor progression in patient-derived medulloblastoma xenograph models. These results detail the neuro-inflammatory mechanisms leading to vincristine-induced peripheral neuropathy and suggest that repurposing anakinra may be an effective co-treatment strategy to prevent vincristine-induced peripheral neuropathy.
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Affiliation(s)
- Hana Starobova
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Queensland, Australia
| | - Mercedes Monteleone
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Queensland, Australia
| | - Christelle Adolphe
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Queensland, Australia
| | - Lena Batoon
- Mater Research Institute and Faculty of Medicine, The University of Queensland, Woolloongabba, Queensland, Australia
- Translational Research Institute, Woolloongabba, Queensland, Australia
| | - Cheyenne J. Sandrock
- Mater Research Institute and Faculty of Medicine, The University of Queensland, Woolloongabba, Queensland, Australia
- Translational Research Institute, Woolloongabba, Queensland, Australia
| | - Bryan Tay
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Queensland, Australia
| | - Jennifer R. Deuis
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Queensland, Australia
| | - Alexandra V. Smith
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Queensland, Australia
| | - Alexander Mueller
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Queensland, Australia
| | - Evelyn Israel Nadar
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Queensland, Australia
| | - Grace Pamo Lawrence
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Queensland, Australia
| | - Amanda Mayor
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Queensland, Australia
| | - Elissa Tolson
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Queensland, Australia
| | - Jean-Pierre Levesque
- Mater Research Institute and Faculty of Medicine, The University of Queensland, Woolloongabba, Queensland, Australia
- Translational Research Institute, Woolloongabba, Queensland, Australia
| | - Allison R. Pettit
- Mater Research Institute and Faculty of Medicine, The University of Queensland, Woolloongabba, Queensland, Australia
- Translational Research Institute, Woolloongabba, Queensland, Australia
| | - Brandon J. Wainwright
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Queensland, Australia
| | - Kate Schroder
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Queensland, Australia
| | - Irina Vetter
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Queensland, Australia
- The School of Pharmacy, The University of Queensland, Woolloongabba, Queensland, Australia
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6
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Adolphe C, Xue A, Fard AT, Genovesi LA, Yang J, Wainwright BJ. Genetic and functional interaction network analysis reveals global enrichment of regulatory T cell genes influencing basal cell carcinoma susceptibility. Genome Med 2021; 13:19. [PMID: 33549134 PMCID: PMC7866769 DOI: 10.1186/s13073-021-00827-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 01/07/2021] [Indexed: 01/02/2023] Open
Abstract
BACKGROUND Basal cell carcinoma (BCC) of the skin is the most common form of human cancer, with more than 90% of tumours presenting with clear genetic activation of the Hedgehog pathway. However, polygenic risk factors affecting mechanisms such as DNA repair and cell cycle checkpoints or which modulate the tumour microenvironment or host immune system play significant roles in determining whether genetic mutations culminate in BCC development. We set out to define background genetic factors that play a role in influencing BCC susceptibility via promoting or suppressing the effects of oncogenic drivers of BCC. METHODS We performed genome-wide association studies (GWAS) on 17,416 cases and 375,455 controls. We subsequently performed statistical analysis by integrating data from population-based genetic studies of multi-omics data, including blood- and skin-specific expression quantitative trait loci and methylation quantitative trait loci, thereby defining a list of functionally relevant candidate BCC susceptibility genes from our GWAS loci. We also constructed a local GWAS functional interaction network (consisting of GWAS nearest genes) and another functional interaction network, consisting specifically of candidate BCC susceptibility genes. RESULTS A total of 71 GWAS loci and 46 functional candidate BCC susceptibility genes were identified. Increased risk of BCC was associated with the decreased expression of 26 susceptibility genes and increased expression of 20 susceptibility genes. Pathway analysis of the functional candidate gene regulatory network revealed strong enrichment for cell cycle, cell death, and immune regulation processes, with a global enrichment of genes and proteins linked to TReg cell biology. CONCLUSIONS Our genome-wide association analyses and functional interaction network analysis reveal an enrichment of risk variants that function in an immunosuppressive regulatory network, likely hindering cancer immune surveillance and effective antitumour immunity.
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Affiliation(s)
- Christelle Adolphe
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD, 4072, Australia
- The University of Queensland Diamantina Institute, Translational Research Institute, Woolloongabba, QLD, 4102, Australia
| | - Angli Xue
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Atefeh Taherian Fard
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Laura A Genovesi
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD, 4072, Australia
- The University of Queensland Diamantina Institute, Translational Research Institute, Woolloongabba, QLD, 4102, Australia
| | - Jian Yang
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD, 4072, Australia.
- School of Life Sciences, Westlake University, Hangzhou, 310024, Zhejiang, China.
- Westlake Laboratory of Life Sciences and Biomedicine, Hangzhou, 310024, Zhejiang, China.
| | - Brandon J Wainwright
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD, 4072, Australia.
- The University of Queensland Diamantina Institute, Translational Research Institute, Woolloongabba, QLD, 4102, Australia.
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7
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Villani R, Hodgson S, Legrand J, Greaney J, Wong HY, Pichol-Thievend C, Adolphe C, Wainwight B, Francois M, Khosrotehrani K. Dominant-negative Sox18 function inhibits dermal papilla maturation and differentiation in all murine hair types. Development 2017; 144:1887-1895. [DOI: 10.1242/dev.143917] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Accepted: 01/19/2017] [Indexed: 12/25/2022]
Abstract
SOX family proteins SOX2 and SOX18 have been reported as being essential in determining hair follicle type; however, the role they play during development remains unclear. Here, we demonstrate that Sox18 regulates the normal differentiation of the dermal papilla of all hair types. In guard (primary) hair dermal condensate (DC) cells, we identified transient Sox18 in addition to SOX2 expression at E14.5, which allowed fate tracing of primary DC cells until birth. Similarly, expression of Sox18 was detected in the DC cells of secondary hairs at E16.5 and in tertiary hair at E18.5. Dominant-negative Sox18 mutation (opposum) did not prevent DC formation in any hair type. However, it affected dermal papilla differentiation, restricting hair formation especially in secondary and tertiary hairs. This Sox18 mutation also prevented neonatal dermal cells or dermal papilla spheres from inducing hair in regeneration assays. Microarray expression studies identified WNT5A and TNC as potential downstream effectors of SOX18 that are important for epidermal WNT signalling. In conclusion, SOX18 acts as a mesenchymal molecular switch necessary for the formation and function of the dermal papilla in all hair types.
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Affiliation(s)
- Rehan Villani
- The University of Queensland, UQ Centre for Clinical Research, Royal Brisbane Hospital, Herston Road, Herston, Brisbane 4029, Queensland, Australia
- The University of Queensland, UQ Diamantina Institute, Translational Research Institute, 37 Kent Street, Woolloongabba, Brisbane 4102, Queensland, Australia
| | - Samantha Hodgson
- The University of Queensland, UQ Centre for Clinical Research, Royal Brisbane Hospital, Herston Road, Herston, Brisbane 4029, Queensland, Australia
| | - Julien Legrand
- The University of Queensland, UQ Centre for Clinical Research, Royal Brisbane Hospital, Herston Road, Herston, Brisbane 4029, Queensland, Australia
| | - Jessica Greaney
- The University of Queensland, UQ Diamantina Institute, Translational Research Institute, 37 Kent Street, Woolloongabba, Brisbane 4102, Queensland, Australia
| | - Ho Yi Wong
- The University of Queensland, UQ Centre for Clinical Research, Royal Brisbane Hospital, Herston Road, Herston, Brisbane 4029, Queensland, Australia
| | - Cathy Pichol-Thievend
- The University of Queensland, Institute for Molecular Bioscience, 306 Carmody Road, St Lucia, Brisbane 4072, Queensland, Australia
| | - Christelle Adolphe
- The University of Queensland, Institute for Molecular Bioscience, 306 Carmody Road, St Lucia, Brisbane 4072, Queensland, Australia
| | - Brandon Wainwight
- The University of Queensland, Institute for Molecular Bioscience, 306 Carmody Road, St Lucia, Brisbane 4072, Queensland, Australia
| | - Mathias Francois
- The University of Queensland, Institute for Molecular Bioscience, 306 Carmody Road, St Lucia, Brisbane 4072, Queensland, Australia
| | - Kiarash Khosrotehrani
- The University of Queensland, UQ Centre for Clinical Research, Royal Brisbane Hospital, Herston Road, Herston, Brisbane 4029, Queensland, Australia
- The University of Queensland, UQ Diamantina Institute, Translational Research Institute, 37 Kent Street, Woolloongabba, Brisbane 4102, Queensland, Australia
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8
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Adolphe C, Junker JP, Lyubimova A, van Oudenaarden A, Wainwright B. Patched Receptors Sense, Interpret, and Establish an Epidermal Hedgehog Signaling Gradient. J Invest Dermatol 2016; 137:179-186. [PMID: 27498049 DOI: 10.1016/j.jid.2016.06.632] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2015] [Revised: 06/01/2016] [Accepted: 06/14/2016] [Indexed: 01/24/2023]
Abstract
By using the sensitivity of single-molecule fluorescent in situ hybridization, we have precisely quantified the levels and defined the temporal and spatial distribution of Hedgehog signaling activity during embryonic skin development and discovered that there is a Hedgehog signaling gradient along the proximal-distal axis of developing hair follicles. To explore the contribution of Hedgehog receptors Ptch1 and Ptch2 in establishing the epidermal signaling gradient, we quantitated the level of pathway activity generated in Ptch1- and Ptch1;Ptch2-deficient skin and defined the contribution of each receptor to regulation of the levels of Hedgehog signaling identified in wild-type skin. Moreover, we show that both the cellular phenotype and level of pathway activity featured in Ptch1;Ptch2-deficient cells faithfully recapitulates the Peak level of endogenous Hedgehog signaling detected at the base of developing follicles, where the concentration of endogenous Shh is predicted to be highest. Taken together, these data show that both Ptch1 and Ptch2 play a crucial role in sensing the concentration of Hedgehog ligand and regulating the appropriate dose-dependent response.
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Affiliation(s)
- Christelle Adolphe
- Division of Molecular Genetics and Development, Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia
| | - Jan Philipp Junker
- Hubrecht Institute, KNAW and University Medical Centre Utrecht, Utrecht, The Netherlands; Berlin Institute for Medical Systems Biology, Max Delbrück Center for Molecular Medicine, Berlin-Buch, Germany
| | - Anna Lyubimova
- Hubrecht Institute, KNAW and University Medical Centre Utrecht, Utrecht, The Netherlands
| | | | - Brandon Wainwright
- Division of Molecular Genetics and Development, Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia.
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Adolphe C, Nieuwenhuis E, Villani R, Li ZJ, Kaur P, Hui CC, Wainwright BJ. Patched 1 and patched 2 redundancy has a key role in regulating epidermal differentiation. J Invest Dermatol 2014; 134:1981-1990. [PMID: 24492243 DOI: 10.1038/jid.2014.63] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Revised: 12/05/2013] [Accepted: 12/30/2013] [Indexed: 11/09/2022]
Abstract
The Patched 1 (Ptch1) receptor has a pivotal role in inhibiting the activity of the Hedgehog (Hh) pathway and is therefore critical in preventing the onset of many human developmental disorders and tumor formation. However, the functional role of the mammalian Ptch2 paralogue remains elusive, particularly the extent to which it contributes to regulating the spatial and temporal activity of Hh signaling. Here we demonstrate in three independent mouse models of epidermal development that in vivo ablation of both Ptch receptors results in a more severe phenotype than loss of Ptch1 alone. Our studies indicate that concomitant loss of Ptch1 and Ptch2 activity inhibits epidermal lineage specification and differentiation. These results reveal that repression of Hh signaling through a dynamic Ptch regulatory network is a crucial event in lineage fate determination in the skin. In general, our findings implicate Ptch receptor redundancy as a key issue in elucidating the cellular origin of Hh-induced tumors.
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Affiliation(s)
- Christelle Adolphe
- Division of Molecular Genetics and Development, Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Erica Nieuwenhuis
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Rehan Villani
- Division of Molecular Genetics and Development, Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Zhu Juan Li
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, Ontario, Canada; Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Pritinder Kaur
- Epithelial Stem Cell Biology Laboratory, Research Division, Peter MacCallum Cancer Center, Melbourne, Victoria, Australia
| | - Chi-Chung Hui
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, Ontario, Canada; Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada.
| | - Brandon J Wainwright
- Division of Molecular Genetics and Development, Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia.
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Farhat R, Puissesseau G, Pasquet MC, Adolphe C, Mégarbané A, Kitzis A, Ladevèze V. 9 Detection of a novel complex allele c.[869+11C>T;3909C>G] in CFTR gene. J Cyst Fibros 2013. [DOI: 10.1016/s1569-1993(13)60152-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Villani RM, Adolphe C, Palmer J, Waters MJ, Wainwright BJ. Patched1 Inhibits Epidermal Progenitor Cell Expansion and Basal Cell Carcinoma Formation by Limiting Igfbp2 Activity. Cancer Prev Res (Phila) 2010; 3:1222-34. [DOI: 10.1158/1940-6207.capr-10-0082] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Dubois NC, Adolphe C, Ehninger A, Wang RA, Robertson EJ, Trumpp A. Placental rescue reveals a sole requirement for c-Myc in embryonic erythroblast survival and hematopoietic stem cell function. Development 2008; 135:2455-65. [PMID: 18550708 DOI: 10.1242/dev.022707] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The c-Myc protein has been implicated in playing a pivotal role in regulating the expression of a large number of genes involved in many aspects of cellular function. Consistent with this view, embryos lacking the c-myc gene exhibit severe developmental defects and die before midgestation. Here, we show that Sox2Cre-mediated deletion of the conditional c-myc(flox) allele specifically in the epiblast (hence trophoectoderm and primitive endoderm structures are wild type) rescues the majority of developmental abnormalities previously characterized in c-myc knockout embryos, indicating that they are secondary defects and arise as a result of placental insufficiency. Epiblast-restricted c-Myc-null embryos appear morphologically normal and do not exhibit any obvious proliferation defects. Nonetheless, these embryos are severely anemic and die before E12. c-Myc-deficient embryos exhibit fetal liver hypoplasia, apoptosis of erythrocyte precursors and functionally defective definitive hematopoietic stem/progenitor cells. Specific deletion of c-myc(flox) in hemogenic or hepatocytic lineages validate the hematopoietic-specific requirement of c-Myc in the embryo proper and provide in vivo evidence to support a synergism between hematopoietic and liver development. Our results reveal for the first time that physiological levels of c-Myc are essential for cell survival and demonstrate that, in contrast to most other embryonic lineages, erythroblasts and hematopoietic stem/progenitor cells are particularly dependent on c-Myc function.
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Affiliation(s)
- Nicole C Dubois
- Ecole Polytechnique Fédérale de Lausanne, Swiss Institute for Experimental Cancer Research, School of Life Science, 1066 Epalinges, Switzerland
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Cheymol J, Dalion J, Adolphe M, Adolphe C. Sur les crises convulsives produites par irradiation massive de la tête du lapin. Pharmacology 2008. [DOI: 10.1159/000134789] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Wilson A, Oser GM, Jaworski M, Blanco-Bose WE, Laurenti E, Adolphe C, Essers MA, Macdonald HR, Trumpp A. Dormant and Self-Renewing Hematopoietic Stem Cells and Their Niches. Ann N Y Acad Sci 2007; 1106:64-75. [PMID: 17442778 DOI: 10.1196/annals.1392.021] [Citation(s) in RCA: 159] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
In the mouse, over the last 20 years, a set of cell-surface markers and activities have been identified, enabling the isolation of bone marrow (BM) populations highly enriched in hematopoietic stem cells (HSCs). These HSCs have the ability to generate multiple lineages and are capable of long-term self-renewal activity such that they are able to reconstitute and maintain a functional hematopoietic system after transplantation into lethally irradiated recipients. Using single-cell reconstitution assays, various marker combinations can be used to achieve a functional HSC purity of almost 50%. Here we have used the differential expression of six of these markers (Sca1, c-Kit, CD135, CD48, CD150, and CD34) on lineage-depleted BM to refine cell hierarchies within the HSC population. At the top of the hierarchy, we propose a dormant HSC population (Lin(-)Sca1(+)c-Kit(+) CD48(-)CD150(+)CD34(-)) that gives rise to an active self-renewing CD34(+) HSC population. HSC dormancy, as well as the balance between self-renewal and differentiation activity, is at least, in part, controlled by the stem cell niches individual HSCs are attached to. Here we review the current knowledge about HSC niches and propose that dormant HSCs are located in niches at the endosteum, whereas activated HSCs are in close contact to sinusoids of the BM microvasculature.
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Affiliation(s)
- Anne Wilson
- Ludwig Institute for Cancer Research Lausanne Branch, University of Lausanne, 1066 Epalinges, Switzerland
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Abstract
Mutations in the Hedgehog receptor, Patched 1 (Ptch1), have been linked to both familial and sporadic forms of basal cell carcinoma (BCC), leading to the hypothesis that loss of Ptch1 function is sufficient for tumor progression. By combining conditional knockout technology with the inducible activity of the Keratin6 promoter, we provide in vivo evidence that loss of Ptch1 function from the basal cell population of mouse skin is sufficient to induce rapid skin tumor formation, reminiscent of human BCC. Elimination of Ptch1 does not promote the nuclear translocation of beta-catenin and does not induce ectopic activation or expression of Notch pathway constituents. In the absence of Ptch1, however, a large proportion of basal cells exhibit nuclear accumulation of the cell cycle regulators cyclin D1 and B1. Collectively, our data suggest that Ptch1 likely functions as a tumor suppressor by inhibiting G1-S phase and G2-M phase cell cycle progression, and the rapid onset of tumor progression clearly indicates Ptch1 functions as a "gatekeeper." In addition, we note the high frequency and rapid onset of tumors in this mouse model makes it an ideal system for testing therapeutic strategies, such as Patched pathway inhibitors.
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MESH Headings
- Animals
- Carcinoma, Basal Cell/genetics
- Carcinoma, Basal Cell/metabolism
- Carcinoma, Basal Cell/pathology
- Cell Cycle/physiology
- Cell Nucleus/metabolism
- Cell Transformation, Neoplastic/genetics
- Cell Transformation, Neoplastic/metabolism
- Cell Transformation, Neoplastic/pathology
- Cyclin B/metabolism
- Cyclin B1
- Cyclin D1/metabolism
- Hair Follicle/metabolism
- Hair Follicle/pathology
- Mice
- Mice, Transgenic
- Patched Receptors
- Patched-1 Receptor
- Receptors, Cell Surface/biosynthesis
- Receptors, Cell Surface/genetics
- Receptors, Cell Surface/physiology
- Receptors, Notch/metabolism
- Skin/metabolism
- Skin/pathology
- Skin Neoplasms/genetics
- Skin Neoplasms/metabolism
- Skin Neoplasms/pathology
- beta Catenin/metabolism
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Affiliation(s)
- Christelle Adolphe
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
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Simpson F, Lammerts van Bueren K, Butterfield N, Bennetts JS, Bowles J, Adolphe C, Simms LA, Young J, Walsh MD, Leggett B, Fowles LF, Wicking C. The PCNA-associated factor KIAA0101/p15 binds the potential tumor suppressor product p33ING1b. Exp Cell Res 2006; 312:73-85. [PMID: 16288740 DOI: 10.1016/j.yexcr.2005.09.020] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2005] [Revised: 09/27/2005] [Accepted: 09/29/2005] [Indexed: 10/25/2022]
Abstract
The KIAA0101/p15(PAF)/OEATC-1 protein was initially isolated in a yeast two-hybrid screen for proliferating cell nuclear antigen (PCNA) binding partners, and was shown to bind PCNA competitively with the cell cycle regulator p21(WAF). PCNA is involved in DNA replication and damage repair. Using polyclonal antisera raised against a p15(PAF) fusion protein, we have shown that in a range of mammalian tumor and non-tumor cell lines the endogenous p15(PAF) protein localises to the nucleus and the mitochondria. Under normal conditions no co-localisation with PCNA could be detected, however following exposure to UV it was possible to co-immunoprecipitate p15(PAF) and PCNA from a number of cell lines, suggesting a UV-enhanced association of the two proteins. Overexpression of p15(PAF) in mammalian cells was also found to protect cells from UV-induced cell death. Based on similarities between the behaviour of p15(PAF) and the potential tumor suppressor product p33ING1b, we have further shown that these two proteins interact in the same complex in cell cultures. This suggests that p15(PAF) forms part of a larger protein complex potentially involved in the regulation of DNA repair, apoptosis and cell cycle progression.
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Affiliation(s)
- Fiona Simpson
- Institute for Molecular Bioscience, The University of Queensland, St Lucia, Brisbane, Queensland 4072, Australia
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17
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Abstract
A significant proportion of the human population suffers from some form of skin disorder, whether it be from burn injury or inherited skin anomalies. The ideal treatment for skin disorders would be to regrow skin tissue from stem cells residing in the individual patient's skin. Locating these adult stem cells and elucidating the molecules involved in orchestrating the production of new skin cells are important steps in devising more-efficient methods of skin production and wound healing via the ex vivo expansion of patient keratinocytes in culture. This review focuses on the structure of the skin, the identification of skin stem cells, and the role of Notch, Wnt and Hedgehog signalling cascades in regulating the fate of epidermal stem cells.
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Affiliation(s)
- Christelle Adolphe
- Institute for Molecular Bioscience, Queensland Bioscience Precinct, Building 80, Services Road, University of Queensland, St Lucia, 4072, Brisbane, Queensland, Australia.
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Adolphe C, Narang M, Ellis T, Wicking C, Kaur P, Wainwright B. An in vivo comparative study of sonic, desert and Indian hedgehog reveals that hedgehog pathway activity regulates epidermal stem cell homeostasis. Development 2004; 131:5009-19. [PMID: 15371305 DOI: 10.1242/dev.01367] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Despite the well-characterised role of sonic hedgehog (Shh) in promoting interfollicular basal cell proliferation and hair follicle downgrowth, the role of hedgehog signalling during epidermal stem cell fate remains largely uncharacterised. In order to determine whether the three vertebrate hedgehog molecules play a role in regulating epidermal renewal we overexpressed sonic(Shh), desert (Dhh) and Indian (Ihh) hedgehog in the basal cells of mouse skin under the control of the human keratin 14 promoter. We observed no overt epidermal morphogenesis phenotype in response to Ihh overexpression, however Dhh overexpression resulted in a range of embryonic and adult skin manifestations indistinguishable from Shh overexpression. Two distinct novel phenotypes were observed amongst Shh and Dhh transgenics, one exhibiting epidermal progenitor cell hyperplasia with the other displaying a complete loss of epidermal tissue renewal indicating deregulation of stem cell activity. These data suggest that correct temporal regulation of hedgehog activity is a key factor in ensuring epidermal stem cell maintenance. In addition, we observed Shh and Dhh transgenic skin from both phenotypes developed lesions reminiscent of human basal cell carcinoma (BCC), indicating that BCCs can be generated despite the loss of much of the proliferative (basal) compartment. These data suggest the intriguing possibility that BCC can arise outside the stem cell population. Thus the elucidation of Shh (and Dhh)target gene activation in the skin will likely identify those genes responsible for increasing the proliferative potential of epidermal basal cells and the mechanisms involved in regulating epidermal stem cell fate.
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Affiliation(s)
- Christelle Adolphe
- Institute for Molecular Bioscience, and Special Research Centre for Functional and Applied Genomics, University of Queensland, Victoria, Australia
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Ellis T, Smyth I, Riley E, Bowles J, Adolphe C, Rothnagel JA, Wicking C, Wainwright BJ. Overexpression of Sonic Hedgehog suppresses embryonic hair follicle morphogenesis. Dev Biol 2003; 263:203-15. [PMID: 14597196 DOI: 10.1016/s0012-1606(03)00394-4] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The Sonic Hedgehog (Shh) signalling pathway plays a central role in the development of the skin and hair follicle and is a major determinant of skin tumorigenesis, most notably of basal cell carcinoma (BCC). Various mouse models involving either ablation or overexpression of key members of the Shh signalling pathway display a range of skin tumours. To further examine the role of Shh in skin development, we have overexpressed Shh in a subset of interfollicular basal cells from 12.5 dpc under the control of the human keratin 1 (HK1) promoter. The HK1-Shh transgenic mice display a range of skin anomalies, including highly pigmented inguinal lesions and regions of alopecia. The most striking hair follicle phenotype is a suppression in embryonic follicle development between 14.0 and 19.0 dpc, resulting in a complete absence of guard, awl, and auchene hair fibres. These data indicate that alternative signals are responsible for the development of different hair follicles and point to a major role of Shh signalling in the morphogenesis of guard, awl, and auchene hair fibres. Through a comparison with other mouse models, the characteristics of the HK1-Shh transgenic mice suggest that the precise timing and site of Shh expression are key in dictating the resultant skin and tumour phenotype.
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Affiliation(s)
- Tammy Ellis
- Institute for Molecular Bioscience, University of Queensland, Brisbane, Queensland, Australia
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