1
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He X, Zhang Y, Fang Q, Sun Y, Zheng X, Fu Y, Fan W, Yang L, Hong Y, Du Y, Wang Z, Chen L. Unraveling the role of CD24 in Hepatocellular carcinoma: Involvement of inactivated Hippo signaling and SOX4-mediated regulation. Biochim Biophys Acta Mol Basis Dis 2024; 1870:167117. [PMID: 38462024 DOI: 10.1016/j.bbadis.2024.167117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 03/03/2024] [Accepted: 03/05/2024] [Indexed: 03/12/2024]
Abstract
Hepatocellular carcinoma (HCC) is a prevalent type of liver cancer, and CD24 gene is reportedly involved in HCC progression. However, the precise regulatory mechanisms of CD24 in HCC remain unclear. In this study, we established a primary HCC mouse model and observed that CD24, induced by inactivation of the Hippo pathway, was highly expressed in HCC. Using a systematic molecular and genomic approach, we identified the Hippo-YAP1-SOX4 pathway as the mechanism through which YAP1 induces CD24 upregulation in HCC cells. CD24 knockdown significantly attenuated YAP1 activation-induced HCC. These findings shed light on the link between CD24 and HCC progression, particularly in the Hippo-inactivated subclass of HCC. Therefore, CD24 may serve as a potential target for specific treatment of this HCC subclass.
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Affiliation(s)
- Xiaobai He
- School of Laboratory Medicine and Bioengineering, Hangzhou Medical College, Hangzhou, China; Zhejiang Provincial Engineering Research Centre for Key Technology of Diagnostic Testing, Hangzhou, China; Zhejiang Provincial Key Laboratory of Biomarkers and In Vitro Diagnostics Translation, Hangzhou, China
| | - Yangyang Zhang
- Department of Clinical Laboratory, University-Town Hospital of Chongqing Medical University, Chongqing, China
| | - Quan Fang
- School of Laboratory Medicine and Bioengineering, Hangzhou Medical College, Hangzhou, China
| | - Yue Sun
- Blood Transfusion Department, Grand Hospital of Shuozhou, Shuozhou, China
| | - Xiaoguang Zheng
- School of Laboratory Medicine and Bioengineering, Hangzhou Medical College, Hangzhou, China
| | - Yu Fu
- School of Laboratory Medicine and Bioengineering, Hangzhou Medical College, Hangzhou, China
| | - Weijiao Fan
- Institute of Clinical Medicine Research, Zhejiang Provincial People's Hospital, Hangzhou Medical College, Hangzhou, Zhejiang 310014, China
| | - Leixiang Yang
- Department of Genetic and Genomic Medicine, Zhejiang Provincial People's Hospital, Affiliated People's Hospital, Hangzhou Medical College, Hangzhou, China
| | - Yeting Hong
- School of Laboratory Medicine and Bioengineering, Hangzhou Medical College, Hangzhou, China
| | - Yaoqiang Du
- Allergy Center, Department of Transfusion Medicine, Ministry of Education Key Laboratory of Laboratory Medicine, Zhejiang Provincial People's Hospital, Affiliated People's Hospital, Hangzhou Medical College, Hangzhou, China.
| | - Zhen Wang
- Zhejiang Provincial Engineering Research Centre for Key Technology of Diagnostic Testing, Hangzhou, China; Allergy Center, Department of Transfusion Medicine, Ministry of Education Key Laboratory of Laboratory Medicine, Zhejiang Provincial People's Hospital, Affiliated People's Hospital, Hangzhou Medical College, Hangzhou, China.
| | - Linjie Chen
- School of Laboratory Medicine and Bioengineering, Hangzhou Medical College, Hangzhou, China; Zhejiang Provincial Engineering Research Centre for Key Technology of Diagnostic Testing, Hangzhou, China; Zhejiang Provincial Key Laboratory of Biomarkers and In Vitro Diagnostics Translation, Hangzhou, China.
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2
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Liang Y, Kaneko K, Xin B, Lee J, Sun X, Zhang K, Feng GS. Temporal analyses of postnatal liver development and maturation by single-cell transcriptomics. Dev Cell 2022; 57:398-414.e5. [PMID: 35134346 PMCID: PMC8842999 DOI: 10.1016/j.devcel.2022.01.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 11/10/2021] [Accepted: 01/05/2022] [Indexed: 02/09/2023]
Abstract
The postnatal development and maturation of the liver, the major metabolic organ, are inadequately understood. We have analyzed 52,834 single-cell transcriptomes and identified 31 cell types or states in mouse livers at postnatal days 1, 3, 7, 21, and 56. We observe unexpectedly high levels of hepatocyte heterogeneity in the developing liver and the progressive construction of the zonated metabolic functions from pericentral to periportal hepatocytes, which is orchestrated with the development of sinusoid endothelial, stellate, and Kupffer cells. Trajectory and gene regulatory analyses capture 36 transcription factors, including a circadian regulator, Bhlhe40, in programming liver development. Remarkably, we identified a special group of macrophages enriched at day 7 with a hybrid phenotype of macrophages and endothelial cells, which may regulate sinusoidal construction and Treg-cell function. This study provides a comprehensive atlas that covers all hepatic cell types and is instrumental for further dissection of liver development, metabolism, and disease.
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Affiliation(s)
- Yan Liang
- Department of Pathology, Division of Biological Sciences, and Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
| | - Kota Kaneko
- Department of Pathology, Division of Biological Sciences, and Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
| | - Bing Xin
- Department of Pathology, Division of Biological Sciences, and Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
| | - Jin Lee
- Department of Pathology, Division of Biological Sciences, and Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
| | - Xin Sun
- Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Kun Zhang
- Department of Bioengineering, University of California, San Diego, La Jolla, CA 92093, USA
| | - Gen-Sheng Feng
- Department of Pathology, Division of Biological Sciences, and Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA.
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3
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Ilic Z, Mondal TK, Guest I, Crawford DR, Sell S. Participation of liver stem cells in cholangiocarcinogenesis after aflatoxin B1 exposure of glutathione S-transferase A3 knockout mice. Tumour Biol 2018; 40:1010428318777344. [DOI: 10.1177/1010428318777344] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Aflatoxin B1, arguably the most potent human carcinogen, induces liver cancer in humans, rats, trout, ducks, and so on, but adult mice are totally resistant. This resistance is because of a detoxifying enzyme, mouse glutathione S-transferase A3, which binds to and inactivates aflatoxin B1 epoxide, preventing the epoxide from binding to DNA and causing mutations. Glutathione S-transferase A3 or its analog has not been detected in any of the sensitive species, including humans. The generation of a glutathione S-transferase A3 knockout (represented as KO or -/-) mice has allowed us to study the induction of liver cancer in mice by aflatoxin B1. In contrast to the induction of hepatocellular carcinomas in other species, aflatoxin B1 induces cholangiocarcinomas in GSTA3-/- mice. In other species and in knockout mice, the induction of liver cancer is preceded by extensive proliferation of small oval cells, providing additional evidence that oval cells are bipolar stem cells and may give rise to either hepatocellular carcinoma or cholangiocarcinoma depending on the nature of the hepatocarcinogen and the species of animal. The recent development of mouse oval cell lines in our laboratory from aflatoxin B1-treated GSTA3-/- mice should provide a new venue for study of the properties and potential of putative mouse liver stem cells.
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Affiliation(s)
- Zoran Ilic
- Wadsworth Center, New York State Department of Health, Albany, NY, USA
| | - Tapan K Mondal
- Wadsworth Center, New York State Department of Health, Albany, NY, USA
| | - Ian Guest
- Wadsworth Center, New York State Department of Health, Albany, NY, USA
| | | | - Stewart Sell
- Wadsworth Center, New York State Department of Health, Albany, NY, USA
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4
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Passman AM, Low J, London R, Tirnitz-Parker JEE, Miyajima A, Tanaka M, Strick-Marchand H, Darlington GJ, Finch-Edmondson M, Ochsner S, Zhu C, Whelan J, Callus BA, Yeoh GCT. A Transcriptomic Signature of Mouse Liver Progenitor Cells. Stem Cells Int 2016; 2016:5702873. [PMID: 27777588 PMCID: PMC5061959 DOI: 10.1155/2016/5702873] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Revised: 08/04/2016] [Accepted: 08/14/2016] [Indexed: 01/07/2023] Open
Abstract
Liver progenitor cells (LPCs) can proliferate extensively, are able to differentiate into hepatocytes and cholangiocytes, and contribute to liver regeneration. The presence of LPCs, however, often accompanies liver disease and hepatocellular carcinoma (HCC), indicating that they may be a cancer stem cell. Understanding LPC biology and establishing a sensitive, rapid, and reliable method to detect their presence in the liver will assist diagnosis and facilitate monitoring of treatment outcomes in patients with liver pathologies. A transcriptomic meta-analysis of over 400 microarrays was undertaken to compare LPC lines against datasets of muscle and embryonic stem cell lines, embryonic and developed liver (DL), and HCC. Three gene clusters distinguishing LPCs from other liver cell types were identified. Pathways overrepresented in these clusters denote the proliferative nature of LPCs and their association with HCC. Our analysis also revealed 26 novel markers, LPC markers, including Mcm2 and Ltbp3, and eight known LPC markers, including M2pk and Ncam. These markers specified the presence of LPCs in pathological liver tissue by qPCR and correlated with LPC abundance determined using immunohistochemistry. These results showcase the value of global transcript profiling to identify pathways and markers that may be used to detect LPCs in injured or diseased liver.
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Affiliation(s)
- Adam M. Passman
- School of Chemistry and Biochemistry, The University of Western Australia, Crawley, WA 6009, Australia
- The Centre for Medical Research, Harry Perkins Institute of Medical Research, Nedlands, WA 6009, Australia
| | - Jasmine Low
- School of Chemistry and Biochemistry, The University of Western Australia, Crawley, WA 6009, Australia
- ARC Centre of Excellence in Plant Energy Biology, The University of Western Australia, Crawley, WA 6009, Australia
| | - Roslyn London
- School of Chemistry and Biochemistry, The University of Western Australia, Crawley, WA 6009, Australia
| | - Janina E. E. Tirnitz-Parker
- School of Biomedical Sciences, Curtin Health Innovation Research Institute, Curtin University, Bentley, WA 6102, Australia
- School of Medicine and Pharmacology, The University of Western Australia, Fremantle, WA 6160, Australia
| | - Atsushi Miyajima
- Institute of Molecular and Cellular Biosciences, The University of Tokyo, Tokyo 113-8654, Japan
| | - Minoru Tanaka
- Institute of Molecular and Cellular Biosciences, The University of Tokyo, Tokyo 113-8654, Japan
| | | | | | - Megan Finch-Edmondson
- Department of Physiology, NUS Yong Loo Lin School of Medicine, Singapore 117411
- Mechanobiology Institute (MBI), National University of Singapore, Singapore 117411
| | - Scott Ochsner
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Cornelia Zhu
- School of Chemistry and Biochemistry, The University of Western Australia, Crawley, WA 6009, Australia
- The Centre for Medical Research, Harry Perkins Institute of Medical Research, Nedlands, WA 6009, Australia
| | - James Whelan
- ARC Centre of Excellence in Plant Energy Biology, The University of Western Australia, Crawley, WA 6009, Australia
- Department of Animal, Plant and Soil Sciences, La Trobe University, Melbourne, VIC 3086, Australia
| | - Bernard A. Callus
- School of Chemistry and Biochemistry, The University of Western Australia, Crawley, WA 6009, Australia
- The Centre for Medical Research, Harry Perkins Institute of Medical Research, Nedlands, WA 6009, Australia
- School of Health Sciences, The University of Notre Dame Australia, Fremantle, WA 6959, Australia
| | - George C. T. Yeoh
- School of Chemistry and Biochemistry, The University of Western Australia, Crawley, WA 6009, Australia
- The Centre for Medical Research, Harry Perkins Institute of Medical Research, Nedlands, WA 6009, Australia
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5
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Ortica S, Tarantino N, Aulner N, Israël A, Gupta-Rossi N. The 4 Notch receptors play distinct and antagonistic roles in the proliferation and hepatocytic differentiation of liver progenitors. FASEB J 2013; 28:603-14. [PMID: 24145721 DOI: 10.1096/fj.13-235903] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The Notch signaling pathway is involved in liver development and regeneration. Here, we investigate the role of the 4 mammalian Notch paralogs in the regulation of hepatoblast proliferation and hepatocytic differentiation. Our model is based on bipotential mouse embryonic liver (BMEL) progenitors that can differentiate into hepatocytes or cholangiocytes in vitro and in vivo. BMEL cells were subjected to Notch antagonists or agonists. Blocking Notch activation with a γ-secretase inhibitor, at 50 μM for 48 h, reduced cell growth by 50%. S-phase entry was impaired, but no apoptosis was induced. A systematic paralog-specific strategy was set using lentiviral transduction with constitutively active forms of each Notch receptor along with inhibition of endogenous Notch signaling. This assay demonstrates that proliferation of BMEL cells requires Notch2 and Notch4 activity, resulting in significant down-regulation of p27(Kip1) and p57(Kip2) cyclin-dependent kinase inhibitors. Conversely, Notch3-expressing cells proliferate less and express 3-fold higher levels of p57(Kip2). The Notch3 cells present a hepatocyte-like morphology, enhanced multinucleation, and a ploidy shift. Moreover, Notch3 activity is conducive to hepatocytic differentiation in vitro, while its paralogs impede this fate. Our study provides the first evidence of a functional diversity among the mammalian Notch homologues in the proliferation and hepatocytic-lineage commitment of liver progenitors.
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Affiliation(s)
- Sara Ortica
- 1Unité de Signalisation Moléculaire et Activation Cellulaire, URA 2582 CNRS, Institut Pasteur, 25 rue du Dr Roux, 75724 Paris Cedex 15, France.
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6
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Recent advances in cancer stem cell research for cholangiocarcinoma. JOURNAL OF HEPATO-BILIARY-PANCREATIC SCIENCES 2013; 19:606-13. [PMID: 22907641 DOI: 10.1007/s00534-012-0542-6] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Cancer stem cells have been identified as cells with the capacity to self-renew and differentiate into multiple lineages of human malignancies. Cholangiocarcinoma is one of the most difficult intra-abdominal malignancies that can be treated using a surgical approach. Chemotherapy in addition to surgery is necessary to improve patient survival. However, its clinical benefit is limited, and, to date, no other effective anticancer drug is available for this disease. Several reports have shown the existence of cholangiocarcinoma stem cells. Cell surface antigens such as CD133, CD24, EpCAM, CD44, and others have been used to isolate cholangiocarcinoma stem cells. In general, enhanced expression of these markers in resected specimens of cholangiocarcinoma was associated with malignant potential. Distinct and specific pathways are expected to be present in cancer stem cells compared to other cancer cells that have no stem cell properties. To date, reports showing possible signaling pathways in cholangiocarcinoma stem cells are limited. More research is anticipated. Targeting therapies for surface molecular markers or specific signaling pathways of cholangiocarcinoma stem cells may be important in order to change the clinical outcome of patients with this disease. However, no clinical trial has been performed so far. This review will focus on the markers and signaling pathways used to define cholangiocarcinoma stem cells. A novel therapeutic approach of targeting cholangiocarcinoma stem cells will also be discussed.
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7
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Zhang J, Li L, Peng L, Sun Y, Li J. An efficient weighted graph strategy to identify differentiation associated genes in embryonic stem cells. PLoS One 2013; 8:e62716. [PMID: 23638139 PMCID: PMC3637163 DOI: 10.1371/journal.pone.0062716] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2012] [Accepted: 03/25/2013] [Indexed: 11/18/2022] Open
Abstract
In the past few decades, embryonic stem cells (ESCs) were of great interest as a model system for studying early developmental processes and because of their potential therapeutic applications in regenerative medicine. However, the underlying mechanisms of ESC differentiation remain unclear, which limits our exploration of the therapeutic potential of stem cells. Fortunately, the increasing quantity and diversity of biological datasets can provide us with opportunities to explore the biological secrets. However, taking advantage of diverse biological information to facilitate the advancement of ESC research still remains a challenge. Here, we propose a scalable, efficient and flexible function prediction framework that integrates diverse biological information using a simple weighted strategy, for uncovering the genetic determinants of mouse ESC differentiation. The advantage of this approach is that it can make predictions based on dynamic information fusion, owing to the simple weighted strategy. With this approach, we identified 30 genes that had been reported to be associated with differentiation of stem cells, which we regard to be associated with differentiation or pluripotency in embryonic stem cells. We also predicted 70 genes as candidates for contributing to differentiation, which requires further confirmation. As a whole, our results showed that this strategy could be applied as a useful tool for ESC research.
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Affiliation(s)
- Jie Zhang
- Department of Prevention, Tongji University School of Medicine, Shanghai, China
- * E-mail: (JZ); (JL)
| | - Li Li
- Key Laboratory of Arrhythmias, Ministry of Education, Tongji University School of Medicine, Shanghai, China
| | - Luying Peng
- Key Laboratory of Arrhythmias, Ministry of Education, Tongji University School of Medicine, Shanghai, China
| | - Yingxian Sun
- Department of Cardiology, The First Hospital of China Medical University, Shenyang, China
| | - Jue Li
- Department of Prevention, Tongji University School of Medicine, Shanghai, China
- * E-mail: (JZ); (JL)
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8
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Schievenbusch S, Sauer E, Curth HM, Schulte S, Demir M, Toex U, Goeser T, Nierhoff D. Neighbor of Punc E 11: Expression Pattern of the New Hepatic Stem/Progenitor Cell Marker During Murine Liver Development. Stem Cells Dev 2012; 21:2656-66. [DOI: 10.1089/scd.2011.0579] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Affiliation(s)
| | - Elisabeth Sauer
- Department of Gastroenterology and Hepatology, University of Cologne, Cologne, Germany
| | - Harald-Morten Curth
- Department of Gastroenterology and Hepatology, University of Cologne, Cologne, Germany
| | - Sigrid Schulte
- Department of Gastroenterology and Hepatology, University of Cologne, Cologne, Germany
| | - Münevver Demir
- Department of Gastroenterology and Hepatology, University of Cologne, Cologne, Germany
| | - Ulrich Toex
- Department of Gastroenterology and Hepatology, University of Cologne, Cologne, Germany
| | - Tobias Goeser
- Department of Gastroenterology and Hepatology, University of Cologne, Cologne, Germany
| | - Dirk Nierhoff
- Department of Gastroenterology and Hepatology, University of Cologne, Cologne, Germany
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9
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Comparative analysis of SV40 17kT and LT function in vivo demonstrates that LT's C-terminus re-programs hepatic gene expression and is necessary for tumorigenesis in the liver. Oncogenesis 2012; 1:e28. [PMID: 23552841 PMCID: PMC3503294 DOI: 10.1038/oncsis.2012.27] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Transformation by Simian Virus 40 (SV40) large T antigen (LT) is mediated in large part by its interaction with a variety of cellular proteins at distinct binding domains within LT. While the interaction of LT's N-terminus with the tumor suppressor Rb is absolutely required for LT-dependent transformation, the requirement for the interaction of LT's C-terminus with p53 is less clear and cell- and context-dependent. Here, we report a line of transgenic mice expressing a doxycycline-inducible liver-specific viral transcript that produces abundant 17kT, a naturally occurring SV40 early product that is co-linear with LT for the first 131 amino acids and that binds to Rb, but not p53. Comparative analysis of livers of transgenic mice expressing either 17kT or full length LT demonstrates that 17kT stimulates cell proliferation and induces hepatic hyperplasia but is incapable of inducing hepatic dysplasia or promoting hepatocarcinogenesis. Gene expression profiling demonstrates that 17kT and LT invoke a set of shared molecular signatures consistent with the action of LT's N-terminus on Rb-E2F-mediated control of hepatocyte transcription. However, 17kT also induces a unique set of genes, many of which are known transcriptional targets of p53, while LT actively suppresses them. LT also uniquely deregulates the expression of a subset of genes within the imprinted network and rapidly re-programs hepatocyte gene expression to a more fetal-like state. Finally, we provide evidence that the LT/p53 complex provides a gain-of-function for LT-dependent transformation in the liver, and confirm the absolute requirement for LT's C-terminus for liver tumor development by demonstrating that phosphatase and tensin homolog (PTEN)-deficiency readily cooperates with LT, but not 17kT, for tumorigenesis. These results confirm independent and inter-dependent functions for LT's N- and C-terminus and emphasize differences in the requirements for LT's C-terminus in cell-type dependent transformation.
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Endo Y, Zhang M, Yamaji S, Cang Y. Genetic abolishment of hepatocyte proliferation activates hepatic stem cells. PLoS One 2012; 7:e31846. [PMID: 22384083 PMCID: PMC3285627 DOI: 10.1371/journal.pone.0031846] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2011] [Accepted: 01/13/2012] [Indexed: 11/20/2022] Open
Abstract
Quiescent hepatic stem cells (HSCs) can be activated when hepatocyte proliferation is compromised. Chemical injury rodent models have been widely used to study the localization, biomarkers, and signaling pathways in HSCs, but these models usually exhibit severe promiscuous toxicity and fail to distinguish damaged and non-damaged cells. Our goal is to establish new animal models to overcome these limitations, thereby providing new insights into HSC biology and application. We generated mutant mice with constitutive or inducible deletion of Damaged DNA Binding protein 1 (DDB1), an E3 ubiquitin ligase, in hepatocytes. We characterized the molecular mechanism underlying the compensatory activation and the properties of oval cells (OCs) by methods of mouse genetics, immuno-staining, cell transplantation and gene expression profiling. We show that deletion of DDB1 abolishes self-renewal capacity of mouse hepatocytes in vivo, leading to compensatory activation and proliferation of DDB1-expressing OCs. Partially restoring proliferation of DDB1-deficient hepatocytes by ablation of p21, a substrate of DDB1 E3 ligase, alleviates OC proliferation. Purified OCs express both hepatocyte and cholangiocyte markers, form colonies in vitro, and differentiate to hepatocytes after transplantation. Importantly, the DDB1 mutant mice exhibit very minor liver damage, compared to a chemical injury model. Microarray analysis reveals several previously unrecognized markers, including Reelin, enriched in oval cells. Here we report a genetic model in which irreversible inhibition of hepatocyte duplication results in HSC-driven liver regeneration. The DDB1 mutant mice can be broadly applied to studies of HSC differentiation, HSC niche and HSCs as origin of liver cancer.
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Affiliation(s)
- Yoko Endo
- Signal Transduction Program, Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
| | - Mingjun Zhang
- Signal Transduction Program, Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
| | - Sachie Yamaji
- Signal Transduction Program, Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
| | - Yong Cang
- Signal Transduction Program, Sanford-Burnham Medical Research Institute, La Jolla, California, United States of America
- Life Sciences Institute, Zhejiang University, Hangzhou, China
- * E-mail:
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11
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Epigenetic modulation of miR-122 facilitates human embryonic stem cell self-renewal and hepatocellular carcinoma proliferation. PLoS One 2011; 6:e27740. [PMID: 22140464 PMCID: PMC3225380 DOI: 10.1371/journal.pone.0027740] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2011] [Accepted: 10/24/2011] [Indexed: 12/20/2022] Open
Abstract
The self-renewal capacity ascribed to hESCs is paralleled in cancer cell proliferation, suggesting that a common network of genes may facilitate the promotion of these traits. However, the molecular mechanisms that are involved in regulating the silencing of these genes as stem cells differentiate into quiescent cellular lineages remain poorly understood. Here, we show that a differentiated cell specific miR-122 exemplifies this regulatory attribute by suppressing the translation of a gene, Pkm2, which is commonly enriched in hESCs and liver cancer cells (HCCs), and facilitates self-renewal and proliferation. Through a series of gene expression analysis, we show that miR-122 expression is highly elevated in quiescent human primary hepatocytes (hPHs) but lost or attenuated in hESCs and HCCs, while an opposing expression pattern is observed for Pkm2. Depleting hESCs and HCCs of Pkm2, or overexpressing miR-122, leads to a common deficiency in self-renewal and proliferation. Likewise, during the differentiation process of hESCs into hepatocytes, a reciprocal expression pattern is observed between miR-122 and Pkm2. An examination of the genomic region upstream of miR-122 uncovered hyper-methylation in hESCs and HCCs, while the same region is de-methylated and occupied by a transcription initiating protein, RNA polymerase II (RNAPII), in hPHs. These findings indicate that one possible mechanism by which hESC self-renewal is modulated in quiescent hepatic derivatives of hESCs is through the regulatory activity of a differentiated cell-specific miR-122, and that a failure to properly turn "on" this miRNA is observed in uncontrollably proliferating HCCs.
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12
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Qiu Q, Hernandez JC, Dean AM, Rao PH, Darlington GJ. CD24-positive cells from normal adult mouse liver are hepatocyte progenitor cells. Stem Cells Dev 2011; 20:2177-88. [PMID: 21361791 DOI: 10.1089/scd.2010.0352] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The identification of specific cell surface markers that can be used to isolate liver progenitor cells will greatly facilitate experimentation to determine the role of these cells in liver regeneration and their potential for therapeutic transplantation. Previously, the cell surface marker, CD24, was observed to be expressed on undifferentiated bipotential mouse embryonic liver stem cells and 3,5-diethoxycarbonyl-1,4-dihydrocollidine-induced oval cells. Here, we describe the isolation and characterization of a rare, primary, nonhematopoietic, CD24+ progenitor cell population from normal, untreated mouse liver. By immunohistochemistry, CD24-expressing cells in normal adult mouse liver were colocalized with CK19-positive cholangiocytes. This nonhematopoietic (CD45-, Ter119-) CD24+ cell population isolated by flow cytometry represented 0.04% of liver cells and expressed several markers of liver progenitor/oval cells. The immunophenotype of nonhematopoietic CD24+ cells was CD133, Dlk, and Sca-1 high, but c-Kit, Thy-1, and CD34 low. The CD24+ cells had increased expression of CK19, epithelial cell adhesion molecule, Sox 9, and FN14 compared with the unsorted cells. Upon transplantation of nonhematopoietic CD24+ cells under the sub-capsule of the livers of Fah knockout mice, cells differentiated into mature functional hepatocytes. Analysis of X and Y chromosome complements were used to determine whether or not fusion of the engrafted cells with the recipient hepatocytes occurred. No cells were found that contained XXXY or any other combination of donor and host sex chromosomes as would be expected if cell fusion had occurred. These results suggested that CD24 can be used as a cell surface marker for isolation of hepatocyte progenitor cells from normal adult liver that are able to differentiate into hepatocytes.
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Affiliation(s)
- Qiong Qiu
- Huffington Center on Aging, Baylor College of Medicine, Houston, Texas 77030, USA
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13
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von Furstenberg RJ, Gulati AS, Baxi A, Doherty JM, Stappenbeck TS, Gracz AD, Magness ST, Henning SJ. Sorting mouse jejunal epithelial cells with CD24 yields a population with characteristics of intestinal stem cells. Am J Physiol Gastrointest Liver Physiol 2011; 300:G409-17. [PMID: 21183658 PMCID: PMC3064119 DOI: 10.1152/ajpgi.00453.2010] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Intestinal stem cells (ISCs) have been studied for more than three decades; however, their isolation has remained a challenge. We hypothesized that, just as for stem cells of other tissues, one or more membrane markers would allow positive selection of ISCs by antibody-based sorting. To explore this hypothesis, microarray data of putative ISC fractions generated by side population sorting and laser capture microdissection were subjected to bioinformatic analysis to identify common membrane antigens. The microarray comparison suggested CD24 as a candidate surface marker, and immunohistochemistry showed expression of CD24 in epithelial cells of crypt bases. Flow cytometry of jejunal epithelial preparations revealed a CD24(+) CD45(-) fraction comprising ∼1% of the cells. Analysis with epithelial cell adhesion molecule and CD31 confirmed that the cell preparations were epithelial and without endothelial contamination. Cycling cells identified by prior injection with 5-ethynyl-2'-deoxyuridine were found predominantly in the CD24(lo) subfraction. Transcript analysis by real-time RT-PCR showed this subfraction to be enriched in the ISC markers leucine-rich-repeat-containing G-protein-coupled receptor 5 (40-fold) and Bmi1 (5-fold), but also enriched in lysozyme (10-fold). Flow cytometry with anti-lysozyme antibodies demonstrated that Paneth cells comprise ∼30% of the CD24(lo) subfraction. Additional flow analyses with leucine-rich-repeat-containing G-protein-coupled receptor 5-enhanced green fluorescent protein (EGFP) epithelium demonstrated colocalization of EGFP(hi) and CD24(lo). In contrast, CD24 cells were negative for the quiescent ISC marker doublecortin and CaM kinase-like-1. Culture of CD24(lo) cells in Matrigel generated organoid structures, which included all four epithelial lineages, thus giving functional evidence for the presence of ISCs. We conclude that the CD24(lo) fraction of jejunal epithelium is highly enriched with cycling ISCs. This isolation method should be useful to many investigators in the field to advance both the basic understanding of ISC biology and the therapeutic applications of ISCs.
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Affiliation(s)
| | | | - Anand Baxi
- 4Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina; and
| | - Jason M. Doherty
- 5Department of Pathology and Immunology, Washington University, St. Louis, Missouri
| | | | - Adam D. Gracz
- Departments of 1Medicine, ,3Cellular and Molecular Physiology, and
| | | | - Susan J. Henning
- Departments of 1Medicine, ,3Cellular and Molecular Physiology, and
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14
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Shupe T, Petersen BE. Potential applications for cell regulatory factors in liver progenitor cell therapy. Int J Biochem Cell Biol 2010; 43:214-21. [PMID: 20851776 DOI: 10.1016/j.biocel.2010.09.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2009] [Revised: 08/24/2010] [Accepted: 09/06/2010] [Indexed: 12/18/2022]
Abstract
Orthotopic liver transplant represent the state of the art treatment for terminal liver pathologies such as cirrhosis in adults and hemochromatosis in neonates. A limited supply of transplantable organs in relationship to the demand means that many patients will succumb to disease before an organ becomes available. One promising alternative to liver transplant is therapy based on the transplant of liver progenitor cells. These cells may be derived from the patient, expanded in vitro, and transplanted back to the diseased liver. Inborn metabolic disorders represent the most attractive target for liver progenitor cell therapy, as many of these disorders may be corrected by repopulation of only a portion of the liver by healthy cells. Another potential application for liver progenitor cell therapy is the seeding of bio-artificial liver matrix. These ex vivo bioreactors may someday be used to bridge critically ill patients to other treatments. Conferring a selective growth advantage to the progenitor cell population remains an obstacle to therapy development. Understanding the molecular signaling mechanisms and micro-environmental cues that govern liver progenitor cell phenotype may someday lead to strategies for providing this selective growth advantage. The discovery of a population of cells within the bone marrow possessing the ability to differentiate into hepatocytes may provide an easily accessible source of cells for liver therapies.
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Affiliation(s)
- Thomas Shupe
- Department of Pathology, Immunology and Laboratory Medicine, University of Florida, College of Medicine, Gainesville, FL 32610-0275, USA.
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15
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Electron microscopic alterations in intermediate hepatocyte-like cells in children with chronic hepatitis B: the first report in pediatric patients. Eur J Gastroenterol Hepatol 2010; 22:741-7. [PMID: 19623079 DOI: 10.1097/meg.0b013e32832e2c09] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
OBJECTIVE The study objective was an in-depth ultrastructural analysis of intermediate hepatocyte-like cells (IHCs), constituting a subpopulation of liver progenitor/oval cells, in children with chronic hepatitis B viral (HBV) infection. METHODS Ultrastructural investigations were conducted on liver biopsy material, fixed in a solution of 2.5% glutaraldehyde, 2% paraformaldehyde, and 0.1 mol/l cacodylate buffer, obtained from 40 children, aged 3-16 years, with chronic hepatitis B. RESULTS Transmission-electron microscopic analysis of liver progenitor/oval cells showed, apart from a morphologically unchanged population of oval cells, the presence of IHCs displaying variously pronounced ultrastructural changes, including degeneration. Interesting was that damaged IHCs were mainly observed in patients with a coexisting advanced liver fibrosis, where they frequently adhered to bundles of collagen fibers. Submicroscopic abnormalities in these cells referred mainly to mitochondria and granular endoplasmic reticulum. The most pronounced mitochondrial alterations observed in degenerating IHCs in the course of chronic HBV infection were characterized by distinct swelling, loss of mitochondrial crests, and the presence of myelin structures within the matrix. In granular endoplasmic reticulum, shortening and segmental degranulation of the reticulum were observed. The above changes were accompanied by the appearance of primitive phagosome-like structures with absorbed biliary pigment. In the vicinity of altered IHCs, transitional hepatic stellate cells could be found. CONCLUSION Our study seems to suggest that chronic HBV infection, lasting from childhood and coexisting with intensive fibrosis may, with the involvement of other carcinogenic factors, promote degenerating IHCs towards neoplastic transformation in adulthood.
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Akkari L, Haouzi D, Binamé F, Floc'h N, Lassus P, Baghdiguian S, Hibner U. Cell shape and TGF-β signaling define the choice of lineage during in vitro differentiation of mouse primary hepatic precursors. J Cell Physiol 2010; 225:186-95. [DOI: 10.1002/jcp.22219] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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17
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Alpha-fetoprotein producing cells act as cancer progenitor cells in human cholangiocarcinoma. Cancer Lett 2010; 294:25-34. [PMID: 20149523 DOI: 10.1016/j.canlet.2010.01.019] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2009] [Revised: 01/12/2010] [Accepted: 01/18/2010] [Indexed: 12/26/2022]
Abstract
We aimed to demonstrate that alpha-fetoprotein (AFP)-producing cells in cholangiocarcinomas possessed cancer stem cell (CSC)-like properties. AFP enhancer/promoter-driven EGFP gene was transfected into human cholangiocarcinoma cell lines. One cell line, RBE, expressed both AFP and EGFP. Clonal analyses revealed that one EGFP-positive cell generated both EGFP-positive and EGFP-negative cell fractions. However, one EGFP-negative cell never produced EGFP-positive cells. The EGFP-positive cells had a greater tumorigenic potential. Only the EGFP-positive cells expressed Notch1. AFP and Notch1 expression was observed in clinical intrahepatic cholangiocarcinomas. The AFP-producing cells were suggested to be CSCs. The Notch pathway might play an important role in maintaining the CSC characteristics.
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Schotanus BA, van den Ingh TSGAM, Penning LC, Rothuizen J, Roskams TA, Spee B. Cross-species immunohistochemical investigation of the activation of the liver progenitor cell niche in different types of liver disease. Liver Int 2009; 29:1241-52. [PMID: 19490419 DOI: 10.1111/j.1478-3231.2009.02024.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
BACKGROUND When hepatocyte replication during liver disease is insufficient for regeneration, liver progenitor cells (LPCs) are activated. The cells and stroma in the immediate environment of LPCs, together termed the LPC niche, are thought to play an important role in this activation. Among these cells are the hepatic stellate cells (HSCs)/myofibroblasts (MFs). AIMS/METHODS We assessed the activation of HSC/MFs and LPCs in relation to the histological location and extent of liver disease in immunohistochemically (double) stained serial sections. Markers of HSC/MFs [alpha-smooth muscle actin, glial fibrillary acidic protein (GFAP), neurotrophin 3 and neural-cell adhesion molecule], markers of LPCs (keratin 7 and keratin 19) and a proliferation marker (Ki67) were used. A very relevant spontaneous model to evaluate LPC niche activation in a translational approach seems to be the dog. Therefore, both human and canine liver diseases with different degree of fibrosis and disease activity were included. RESULTS In human and canine liver disease, type and extent of LPC niche activation depended on type and severity of disease (P<0.05) and corresponded to the main location of disease. Activated HSCs surrounded the activated LPCs. In chronic hepatitis and non-alcoholic steatohepatitis lobular-type HSCs were activated, while during biliary disease portal/septal MFs were mainly activated. In canine liver, GFAP further presented as an early marker of HSC activation. Activation of the LPCs correlated with disease location and severity (P<0.01), and was inversely related to hepatocyte proliferation, as was previously shown in man. CONCLUSION A shared involvement of HSC/MFs, LPCs and disease severity during hepatic disease processes is shown, which is highly similar in man and dog.
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Affiliation(s)
- Baukje A Schotanus
- Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands.
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Li D, Zheng L, Jin L, Zhou Y, Li H, Fu J, Shi M, Du P, Wang L, Wu H, Chen GY, Zheng P, Liu Y, Wang FS, Wang S. CD24 polymorphisms affect risk and progression of chronic hepatitis B virus infection. Hepatology 2009; 50:735-42. [PMID: 19610054 DOI: 10.1002/hep.23047] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
UNLABELLED T-cell immunity to hepatitis B virus (HBV) is involved in both viral clearance and the pathogenesis of cirrhosis and hepatocellular carcinoma following chronic HBV infection. It is therefore of great interest to analyze whether genetic polymorphism of genes involved in the immune response may determine the outcomes of chronic HBV infection. Here we report that CD24 polymorphisms affect the risk and progression of chronic HBV infection. Thus the CD24 P170(T) allele, which is expressed at a higher level, is associated with an increased risk of chronic HBV infection. Among the chronic HBV patients this allele shows recessive association with more rapid progression to liver cirrhosis and hepatocellular carcinoma in comparison to the P170(C) allele. In contrast, a dinucleotide deletion at position 1527-1528 (P1527(del)), which reduces CD24 expression, is associated with a significantly reduced risk of chronic HBV infection. To confirm the role for CD24 in liver carcinogenesis, we compared the size of liver tumor developed in CD24(-/-) and CD24(+/-) HBV transgenic mice. Our data demonstrate that targeted mutation of CD24 drastically reduced the sizes of spontaneous liver cancer in the HBV transgenic mice. CONCLUSION These data demonstrate that genetic variation of CD24 may be an important determinant for the outcome of chronic HBV infection.
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Affiliation(s)
- Dongling Li
- Center for Infection and Immunity, National Laboratory of Biomacromolecules, Institute of Biophysics, Beijing, China
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Chen GY, Tang J, Zheng P, Liu Y. CD24 and Siglec-10 selectively repress tissue damage-induced immune responses. Science 2009; 323:1722-5. [PMID: 19264983 PMCID: PMC2765686 DOI: 10.1126/science.1168988] [Citation(s) in RCA: 582] [Impact Index Per Article: 38.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Patten recognition receptors, which recognize pathogens or components of injured cells (danger), trigger activation of the innate immune system. Whether and how the host distinguishes between danger- versus pathogen-associated molecular patterns remains unresolved. We report that CD24-deficient mice exhibit increased susceptibility to danger- but not pathogen-associated molecular patterns. CD24 associates with high mobility group box 1, heat shock protein 70, and heat shock protein 90; negatively regulates their stimulatory activity; and inhibits nuclear factor kappaB (NF-kappaB) activation. This occurs at least in part through CD24 association with Siglec-10 in humans or Siglec-G in mice. Our results reveal that the CD24-Siglec G pathway protects the host against a lethal response to pathological cell death and discriminates danger- versus pathogen-associated molecular patterns.
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Affiliation(s)
- Guo-Yun Chen
- Division of Immunotherapy, Department of Surgery, University of Michigan School of Medicine, Ann Arbor, MI 48109, USA
| | - Jie Tang
- Institute of Biophysics, Chinese Academy of Science, Beijing, China
| | - Pan Zheng
- Division of Immunotherapy, Department of Surgery, University of Michigan School of Medicine, Ann Arbor, MI 48109, USA
- Division of Immunotherapy, Department of Pathology, University of Michigan School of Medicine, Ann Arbor, MI 48109, USA
| | - Yang Liu
- Division of Immunotherapy, Department of Surgery, University of Michigan School of Medicine, Ann Arbor, MI 48109, USA
- Division of Immunotherapy, Department of Internal Medicine, University of Michigan School of Medicine, Ann Arbor, MI 48109, USA
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Delisle JC, Martignat L, Bach JM, Bösch S, Louzier V. Bipotential mouse embryonic liver (BMEL) cells spontaneously express Pdx1 and Ngn3 but do not undergo further pancreatic differentiation upon Hes1 down-regulation. BMC Res Notes 2008; 1:136. [PMID: 19108739 PMCID: PMC2649931 DOI: 10.1186/1756-0500-1-136] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2008] [Accepted: 12/24/2008] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Liver-to-pancreas conversion offers new possibilities for beta-cell engineering for type 1 diabetes therapy. Among conceivable sources of liver cells, we focused on BMEL cells. These untransformed mouse embryonic liver cells have been reproducibly isolated from different inbred mice strains and have the potential to differentiate into hepatocytes and cholangiocytes in vitro and in vivo. FINDINGS Strikingly, we find here that adherent BMEL cells display functional similarities with multipotent pancreatic precursor cells, namely Pdx1 and Ngn3 expression, and further express Hnf6 in floating aggregate culture. Hes1, a direct repressor of Ngn3 and pancreatic endocrine commitment, is expressed in adherent BMEL cells and decreases with time in aggregate culture. However, Hes1 decrease fails to initiate activation of late-stage pancreatic endocrine transcription factors. CONCLUSION Here we report that BMEL cells present features of pancreatic endocrine progenitor cells. In the field of diabetes research, BMEL cells are of potential interest for the study of inductive signals critical for in vitro beta-cell maturation in-liver-to-pancreas conversion.
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Sirica AE, Nathanson MH, Gores GJ, Larusso NF. Pathobiology of biliary epithelia and cholangiocarcinoma: proceedings of the Henry M. and Lillian Stratton Basic Research Single-Topic Conference. Hepatology 2008; 48:2040-6. [PMID: 18855901 PMCID: PMC3724356 DOI: 10.1002/hep.22623] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
In June 2008, the American Association for the Study of Liver Diseases (AASLD) sponsored the Henry M. and Lillian Stratton Basic Research Single-Topic Conference on the Pathobiology of Biliary Epithelia and Cholangiocarcinoma, which was held in Atlanta, GA. Attendees from 12 different countries participated in this conference, making it a truly international scientific event. Both oral and poster presentations were given by multidisciplinary experts, who highlighted important areas of current basic and translational research on biliary epithelial cell biology and pathophysiology, and on the etiology, cellular and molecular pathogenesis, and target-based therapy of cholangiocarcinoma. The specific goals and objectives of the conference were: (1) to advance knowledge of basic and molecular mechanisms underlying developmental and proliferative disorders of the biliary tract; (2) to foster a better and more comprehensive understanding of mechanisms regulating biliary epithelial (cholangiocyte) growth and transport, signaling, cell survival, and abnormalities that result in disease; and (3) to understand basic mechanisms of cholangiocarcinoma development and progression, with the added goal of identifying and exploiting potentially critical molecular pathways that may be targeted therapeutically. A number of interrelated themes emerged from the oral and poster sessions that affected current understandings of the complex organization of transcriptional and signaling mechanisms that regulate bile duct development, hepatic progenitor cell expansion, cholangiocyte secretory functions and proliferation, and mechanisms of cholangiocarcinogenesis and malignant cholangiocyte progression. Most notable were the critical questions raised as to how best to exploit aberrant signaling pathways associated with biliary disease as potential targets for therapy.
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Affiliation(s)
- Alphonse E Sirica
- Division of Cellular and Molecular Pathogenesis, Department of Pathology, Virginia Commonwealth University School of Medicine, Richmond, VA, USA.
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23
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Sell S. Alpha-fetoprotein, stem cells and cancer: how study of the production of alpha-fetoprotein during chemical hepatocarcinogenesis led to reaffirmation of the stem cell theory of cancer. Tumour Biol 2008; 29:161-80. [PMID: 18612221 PMCID: PMC2679671 DOI: 10.1159/000143402] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2008] [Accepted: 05/08/2008] [Indexed: 12/18/2022] Open
Abstract
Identification of the cells in the liver that produce alpha-fetoprotein during development, in response to liver injury and during the early stages of chemical hepatocarcinogenesis led to the conclusion that maturation arrest of liver-determined tissue stem cells was the cellular process that gives rise to hepatocellular carcinomas. When the cellular changes in these processes were compared to that of the formation of teratocarcinomas, the hypothesis arose that all cancers arise from maturation arrest of tissue-determined stem cells. This was essentially a reinterpretation of the embryonal rest theory of cancer whereby tissue stem cells take the role of embryonal rests. A corollary of the stem cell theory of the origin of cancer is that cancers contain the same functional cell populations as normal tissues: stem cells, transit-amplifying cells and mature cells. Cancer stem cells retain the essential feature of normal stem cells: the ability to self-renew. Growth of cancers is due to continued proliferation of cancer transit-amplifying cells that do not differentiate to mature cells (maturation arrest). On the other hand, cancer stem cells generally divide very rarely and contribute little to tumor growth. However, the presence of cancer stem cells in tumors is believed to be responsible for the properties of immortalization, transplantability and resistance to therapy characteristic of cancers. Current therapies for cancer (chemotherapy, radiotherapy, antiangiogenesis and differentiation therapy) are directed against the cancer transit-amplifying cells. When these therapies are discontinued, the cancer reforms from the cancer stem cells. Therapy directed toward interruption of the cell signaling pathways that maintain cancer stem cells could lead to new modalities to the prevention of regrowth of the cancer.
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Affiliation(s)
- Stewart Sell
- Wadsworth Center and Ordway Research Institute, Albany, NY, USA.
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