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Duncan AW. Pathological polyploidy and liver repair failure in RAD51-deficient mice. Hepatology 2024:01515467-990000000-00828. [PMID: 38546299 DOI: 10.1097/hep.0000000000000871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Accepted: 03/15/2024] [Indexed: 04/25/2024]
Affiliation(s)
- Andrew W Duncan
- Department of Pathology, Pittsburgh Liver Research Center, McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
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2
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Bu W, Sun X, Xue X, Geng S, Yang T, Zhang J, Li Y, Feng C, Liu Q, Zhang X, Li P, Liu Z, Shi Y, Shao C. Early onset of pathological polyploidization and cellular senescence in hepatocytes lacking RAD51 creates a pro-fibrotic and pro-tumorigenic inflammatory microenvironment. Hepatology 2024:01515467-990000000-00800. [PMID: 38466833 DOI: 10.1097/hep.0000000000000821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2023] [Accepted: 02/06/2024] [Indexed: 03/13/2024]
Abstract
BACKGROUND AND AIMS RAD51 recombinase (RAD51) is a highly conserved DNA repair protein and is indispensable for embryonic viability. As a result, the role of RAD51 in liver development and function is unknown. Our aim was to characterize the function of RAD51 in postnatal liver development. APPROACH AND RESULTS RAD51 is highly expressed during liver development and during regeneration following hepatectomy and hepatic injury, and is also elevated in chronic liver diseases. We generated a hepatocyte-specific Rad51 deletion mouse model using Alb -Cre ( Rad51 -conditional knockout (CKO)) and Adeno-associated virus 8-thyroxine-binding globulin-cyclization recombination enzyme to evaluate the function of RAD51 in liver development and regeneration. The phenotype in Rad51 -CKO mice is dependent on CRE dosage, with Rad51fl/fl ; Alb -Cre +/+ manifesting a more severe phenotype than the Rad51fl/fl ; Alb -Cre +/- mice. RAD51 deletion in postnatal hepatocytes results in aborted mitosis and early onset of pathological polyploidization that is associated with oxidative stress and cellular senescence. Remarkable liver fibrosis occurs spontaneously as early as in 3-month-old Rad51fl/fl ; Alb -Cre +/+ mice. While liver regeneration is compromised in Rad51 -CKO mice, they are more tolerant of carbon tetrachloride-induced hepatic injury and resistant to diethylnitrosamine/carbon tetrachloride-induced HCC. A chronic inflammatory microenvironment created by the senescent hepatocytes appears to activate ductular reaction the transdifferentiation of cholangiocytes to hepatocytes. The newly derived RAD51 functional immature hepatocytes proliferate vigorously, acquire increased malignancy, and eventually give rise to HCC. CONCLUSIONS Our results demonstrate a novel function of RAD51 in liver development, homeostasis, and tumorigenesis. The Rad51 -CKO mice represent a unique genetic model for premature liver senescence, fibrosis, and hepatocellular carcinogenesis.
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Affiliation(s)
- Wenqing Bu
- State Key Laboratory of Radiation Medicine and Protection, The First Affiliated Hospital of Soochow University, State Key Laboratory of Radiation Medicine and Protection, Institutes for Translational Medicine, Soochow University Suzhou Medical College, Suzhou, Jiangsu, China
| | - Xue Sun
- State Key Laboratory of Radiation Medicine and Protection, The First Affiliated Hospital of Soochow University, State Key Laboratory of Radiation Medicine and Protection, Institutes for Translational Medicine, Soochow University Suzhou Medical College, Suzhou, Jiangsu, China
| | - Xiaotong Xue
- State Key Laboratory of Radiation Medicine and Protection, The First Affiliated Hospital of Soochow University, State Key Laboratory of Radiation Medicine and Protection, Institutes for Translational Medicine, Soochow University Suzhou Medical College, Suzhou, Jiangsu, China
| | - Shengmiao Geng
- State Key Laboratory of Radiation Medicine and Protection, The First Affiliated Hospital of Soochow University, State Key Laboratory of Radiation Medicine and Protection, Institutes for Translational Medicine, Soochow University Suzhou Medical College, Suzhou, Jiangsu, China
| | - Tingting Yang
- State Key Laboratory of Radiation Medicine and Protection, The First Affiliated Hospital of Soochow University, State Key Laboratory of Radiation Medicine and Protection, Institutes for Translational Medicine, Soochow University Suzhou Medical College, Suzhou, Jiangsu, China
| | - Jia Zhang
- State Key Laboratory of Radiation Medicine and Protection, The First Affiliated Hospital of Soochow University, State Key Laboratory of Radiation Medicine and Protection, Institutes for Translational Medicine, Soochow University Suzhou Medical College, Suzhou, Jiangsu, China
| | - Yanan Li
- State Key Laboratory of Radiation Medicine and Protection, The First Affiliated Hospital of Soochow University, State Key Laboratory of Radiation Medicine and Protection, Institutes for Translational Medicine, Soochow University Suzhou Medical College, Suzhou, Jiangsu, China
| | - Chao Feng
- State Key Laboratory of Radiation Medicine and Protection, The First Affiliated Hospital of Soochow University, State Key Laboratory of Radiation Medicine and Protection, Institutes for Translational Medicine, Soochow University Suzhou Medical College, Suzhou, Jiangsu, China
| | - Qiao Liu
- Key Laboratory of Experimental Teratology, Ministry of Education, Department of Molecular Medicine and Genetics, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
| | - Xiyu Zhang
- Key Laboratory of Experimental Teratology, Ministry of Education, Department of Molecular Medicine and Genetics, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
| | - Peishan Li
- State Key Laboratory of Radiation Medicine and Protection, The First Affiliated Hospital of Soochow University, State Key Laboratory of Radiation Medicine and Protection, Institutes for Translational Medicine, Soochow University Suzhou Medical College, Suzhou, Jiangsu, China
| | - Zhaojian Liu
- Key Laboratory of Experimental Teratology, Ministry of Education, Department of Molecular Medicine and Genetics, School of Basic Medical Sciences, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
| | - Yufang Shi
- State Key Laboratory of Radiation Medicine and Protection, The First Affiliated Hospital of Soochow University, State Key Laboratory of Radiation Medicine and Protection, Institutes for Translational Medicine, Soochow University Suzhou Medical College, Suzhou, Jiangsu, China
| | - Changshun Shao
- State Key Laboratory of Radiation Medicine and Protection, The First Affiliated Hospital of Soochow University, State Key Laboratory of Radiation Medicine and Protection, Institutes for Translational Medicine, Soochow University Suzhou Medical College, Suzhou, Jiangsu, China
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3
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Wilson SR, Duncan AW. The Ploidy State as a Determinant of Hepatocyte Proliferation. Semin Liver Dis 2023; 43:460-471. [PMID: 37967885 PMCID: PMC10862383 DOI: 10.1055/a-2211-2144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2023]
Abstract
The liver's unique chromosomal variations, including polyploidy and aneuploidy, influence hepatocyte identity and function. Among the most well-studied mammalian polyploid cells, hepatocytes exhibit a dynamic interplay between diploid and polyploid states. The ploidy state is dynamic as hepatocytes move through the "ploidy conveyor," undergoing ploidy reversal and re-polyploidization during proliferation. Both diploid and polyploid hepatocytes actively contribute to proliferation, with diploids demonstrating an enhanced proliferative capacity. This enhanced potential positions diploid hepatocytes as primary drivers of liver proliferation in multiple contexts, including homeostasis, regeneration and repopulation, compensatory proliferation following injury, and oncogenic proliferation. This review discusses the influence of ploidy variations on cellular activity. It presents a model for ploidy-associated hepatocyte proliferation, offering a deeper understanding of liver health and disease with the potential to uncover novel treatment approaches.
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Affiliation(s)
- Sierra R. Wilson
- Department of Pathology, McGowan Institute for Regenerative Medicine, Pittsburgh Liver Research Center, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Andrew W. Duncan
- Department of Pathology, McGowan Institute for Regenerative Medicine, Pittsburgh Liver Research Center, University of Pittsburgh, Pittsburgh, Pennsylvania
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4
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Clerbaux LA, Cordier P, Desboeufs N, Unger K, Leary P, Semere G, Boege Y, Chan LK, Desdouets C, Lopes M, Weber A. Mcl-1 deficiency in murine livers leads to nuclear polyploidisation and mitotic errors: Implications for hepatocellular carcinoma. JHEP Rep 2023; 5:100838. [PMID: 37663116 PMCID: PMC10472239 DOI: 10.1016/j.jhepr.2023.100838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Revised: 05/15/2023] [Accepted: 06/20/2023] [Indexed: 09/05/2023] Open
Abstract
Background & Aims Mcl-1, an antiapoptotic protein overexpressed in many tumours, including hepatocellular carcinoma (HCC), represents a promising target for cancer treatment. Although Mcl-1 non-apoptotic roles might critically influence the therapeutic potential of Mcl-1 inhibitors, these functions remain poorly understood. We aimed to investigate the effects of hepatic Mcl-1 deficiency (Mcl-1Δhep) on hepatocyte ploidy and cell cycle in murine liver in vivo and the possible implications on HCC. Methods Livers of young Mcl-1Δhep and wild-type (WT) mice were analysed for ploidy profile, mitotic figures, in situ chromosome segregation, gene set enrichment analysis and were subjected to two-thirds partial hepatectomy to assess Mcl-1 deficiency effect on cell cycle progression in vivo. Mcl-1Δhep tumours in older mice were analysed for ploidy profile, chromosomal instability, and mutational signatures via whole exome sequencing. Results In young mice, Mcl-1 deficiency leads to nuclear polyploidy and to high rates of mitotic errors with abnormal spindle figures and chromosome mis-segregation along with a prolonged spindle assembly checkpoint activation signature. Chromosomal instability and altered ploidy profile are observed in Mcl-1Δhep tumours of old mice as well as a characteristic mutational signature of currently unknown aetiology. Conclusions Our study suggests novel non-apoptotic effects of Mcl-1 deficiency on nuclear ploidy, mitotic regulation, and chromosomal segregation in hepatocytes in vivo. In addition, the Mcl-1 deficiency characteristic mutational signature might reflect mitotic issues. These results are of importance to consider when developing anti-Mcl-1 therapies to treat cancer. Impact and implications Although Mcl-1 inhibitors represent promising hepatocellular carcinoma treatment, the still poorly understood non-apoptotic roles of Mcl-1 might compromise their successful clinical application. Our study shows that Mcl-1 deficiency leads to nuclear polyploidy, mitotic errors, and aberrant chromosomal segregation in hepatocytes in vivo, whereas hepatocellular tumours spontaneously induced by Mcl-1 deficiency exhibit chromosomal instability and a mutational signature potentially reflecting mitotic issues. These results have potential implications for the development of anti-Mcl-1 therapies to treat hepatocellular carcinoma, especially as hyperproliferative liver is a clinically relevant situation.
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Affiliation(s)
- Laure-Alix Clerbaux
- Department of Pathology and Molecular Pathology, University Hospital Zürich (USZ), Zurich, Switzerland
- Institute of Molecular Cancer Research (IMCR), University of Zürich (UZH), Zurich, Switzerland
| | - Pierre Cordier
- Centre de Recherche des Cordeliers, Sorbonne Université, INSERM, Université de Paris, Paris, France
- Genomic Instability, Metabolism, Immunity and Liver Tumorigenesis Laboratory, Equipe Labellisée LIGUE 2023, Paris, France
| | - Nina Desboeufs
- Department of Pathology and Molecular Pathology, University Hospital Zürich (USZ), Zurich, Switzerland
- Institute of Molecular Cancer Research (IMCR), University of Zürich (UZH), Zurich, Switzerland
| | - Kristian Unger
- Research Unit Radiation Cytogenetics, Helmholtz Munich, Neuherberg, Germany
- Department of Radiation Oncology, University Hospital, LMU Munich, Munich, Germany
- Bavarian Cancer Research Center (BZKF), Munich, Germany
| | - Peter Leary
- Institute of Molecular Cancer Research (IMCR), University of Zürich (UZH), Zurich, Switzerland
- Functional Genomics Center Zurich, University of Zürich and ETH Zürich, Zurich, Switzerland
| | - Gabriel Semere
- Department of Pathology and Molecular Pathology, University Hospital Zürich (USZ), Zurich, Switzerland
| | - Yannick Boege
- Department of Pathology and Molecular Pathology, University Hospital Zürich (USZ), Zurich, Switzerland
| | - Lap Kwan Chan
- Department of Pathology and Molecular Pathology, University Hospital Zürich (USZ), Zurich, Switzerland
| | - Chantal Desdouets
- Centre de Recherche des Cordeliers, Sorbonne Université, INSERM, Université de Paris, Paris, France
- Genomic Instability, Metabolism, Immunity and Liver Tumorigenesis Laboratory, Equipe Labellisée LIGUE 2023, Paris, France
| | - Massimo Lopes
- Institute of Molecular Cancer Research (IMCR), University of Zürich (UZH), Zurich, Switzerland
| | - Achim Weber
- Department of Pathology and Molecular Pathology, University Hospital Zürich (USZ), Zurich, Switzerland
- Institute of Molecular Cancer Research (IMCR), University of Zürich (UZH), Zurich, Switzerland
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5
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Wen Z, Lin YH, Wang S, Fujiwara N, Rong R, Jin KW, Yang DM, Yao B, Yang S, Wang T, Xie Y, Hoshida Y, Zhu H, Xiao G. Deep-Learning-Based Hepatic Ploidy Quantification Using H&E Histopathology Images. Genes (Basel) 2023; 14:921. [PMID: 37107679 PMCID: PMC10137944 DOI: 10.3390/genes14040921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 03/28/2023] [Accepted: 04/11/2023] [Indexed: 04/29/2023] Open
Abstract
Polyploidy, the duplication of the entire genome within a single cell, is a significant characteristic of cells in many tissues, including the liver. The quantification of hepatic ploidy typically relies on flow cytometry and immunofluorescence (IF) imaging, which are not widely available in clinical settings due to high financial and time costs. To improve accessibility for clinical samples, we developed a computational algorithm to quantify hepatic ploidy using hematoxylin-eosin (H&E) histopathology images, which are commonly obtained during routine clinical practice. Our algorithm uses a deep learning model to first segment and classify different types of cell nuclei in H&E images. It then determines cellular ploidy based on the relative distance between identified hepatocyte nuclei and determines nuclear ploidy using a fitted Gaussian mixture model. The algorithm can establish the total number of hepatocytes and their detailed ploidy information in a region of interest (ROI) on H&E images. This is the first successful attempt to automate ploidy analysis on H&E images. Our algorithm is expected to serve as an important tool for studying the role of polyploidy in human liver disease.
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Affiliation(s)
- Zhuoyu Wen
- Quantitative Biomedical Research Center, Department of Population and Data Sciences, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Yu-Hsuan Lin
- Children’s Research Institute, Departments of Pediatrics and Internal Medicine, Center for Regenerative Science and Medicine, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Shidan Wang
- Quantitative Biomedical Research Center, Department of Population and Data Sciences, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Naoto Fujiwara
- Division of Digestive and Liver Diseases, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Ruichen Rong
- Quantitative Biomedical Research Center, Department of Population and Data Sciences, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Kevin W. Jin
- Quantitative Biomedical Research Center, Department of Population and Data Sciences, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Donghan M. Yang
- Quantitative Biomedical Research Center, Department of Population and Data Sciences, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Bo Yao
- Quantitative Biomedical Research Center, Department of Population and Data Sciences, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Shengjie Yang
- Quantitative Biomedical Research Center, Department of Population and Data Sciences, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Tao Wang
- Quantitative Biomedical Research Center, Department of Population and Data Sciences, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
- Center for the Genetics of Host Defense, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Yang Xie
- Quantitative Biomedical Research Center, Department of Population and Data Sciences, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
- Hamon Center for Regenerative Medicine, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
- Department of Bioinformatics, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Yujin Hoshida
- Division of Digestive and Liver Diseases, Department of Internal Medicine, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Hao Zhu
- Children’s Research Institute, Departments of Pediatrics and Internal Medicine, Center for Regenerative Science and Medicine, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
- Children’s Research Institute Mouse Genome Engineering Core, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Guanghua Xiao
- Quantitative Biomedical Research Center, Department of Population and Data Sciences, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
- Hamon Center for Regenerative Medicine, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
- Department of Bioinformatics, The University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
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6
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Barajas JM, Lin CH, Sun HL, Alencastro F, Zhu AC, Aljuhani M, Navari L, Yilmaz SA, Yu L, Corps K, He C, Duncan AW, Ghoshal K. METTL3 Regulates Liver Homeostasis, Hepatocyte Ploidy, and Circadian Rhythm-Controlled Gene Expression in Mice. THE AMERICAN JOURNAL OF PATHOLOGY 2022; 192:56-71. [PMID: 34599880 PMCID: PMC8759040 DOI: 10.1016/j.ajpath.2021.09.005] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 08/19/2021] [Accepted: 09/15/2021] [Indexed: 01/03/2023]
Abstract
N6-methyladenosine (m6A), the most abundant internal modifier of mRNAs installed by the methyltransferase 13 (METTL3) at the (G/A)(m6A)C motif, plays a critical role in the regulation of gene expression. METTL3 is essential for embryonic development, and its dysregulation is linked to various diseases. However, the role of METTL3 in liver biology is largely unknown. In this study, METTL3 function was unraveled in mice depleted of Mettl3 in neonatal livers (Mettl3fl/fl; Alb-Cre). Liver-specific Mettl3 knockout (M3LKO) mice exhibited global decrease in m6A on polyadenylated RNAs and pathologic features associated with nonalcoholic fatty liver disease (eg, hepatocyte ballooning, ductular reaction, microsteatosis, pleomorphic nuclei, DNA damage, foci of altered hepatocytes, focal lobular and portal inflammation, and elevated serum alanine transaminase/alkaline phosphatase levels). Mettl3-depleted hepatocytes were highly proliferative, with decreased numbers of binucleate hepatocytes and increased nuclear polyploidy. M3LKO livers were characterized by reduced m6A and expression of several key metabolic transcripts regulated by circadian rhythm and decreased nuclear protein levels of the core clock transcription factors BMAL1 and CLOCK. A significant decrease in total Bmal1 and Clock mRNAs but an increase in their nuclear levels were observed in M3LKO livers, suggesting impaired nuclear export. Consistent with the phenotype, methylated (m6A) RNA immunoprecipitation coupled with sequencing and RNA sequencing revealed transcriptome-wide loss of m6A markers and alterations in abundance of mRNAs involved in metabolism in M3LKO. Collectively, METTL3 and m6A modifications are critical regulators of liver homeostasis and function.
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Affiliation(s)
- Juan M Barajas
- Department of Pathology, The Ohio State University, Columbus, Ohio
| | - Cho-Hao Lin
- Department of Pathology, The Ohio State University, Columbus, Ohio; Comprehensive Cancer Center, College of Medicine, The Ohio State University, Columbus, Ohio
| | - Hui-Lung Sun
- Department of Biochemistry and Molecular Biology and Institute for Biophysical Dynamics, Howard Hughes Medical Institute, University of Chicago, Chicago, Illinois
| | - Frances Alencastro
- Department of Pathology, Pittsburgh Liver Research Center, McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pennsylvania
| | - Allen C Zhu
- Department of Biochemistry and Molecular Biology and Institute for Biophysical Dynamics, Howard Hughes Medical Institute, University of Chicago, Chicago, Illinois
| | - Mona Aljuhani
- Department of Pathology, The Ohio State University, Columbus, Ohio
| | - Ladan Navari
- Comprehensive Cancer Center, College of Medicine, The Ohio State University, Columbus, Ohio
| | - Selen A Yilmaz
- Department of Biomedical Informatics, The Ohio State University, Columbus, Ohio
| | - Lianbo Yu
- Department of Biomedical Informatics, The Ohio State University, Columbus, Ohio
| | - Kara Corps
- Department of Veterinary Biosciences, The Ohio State University, Columbus, Ohio
| | - Chuan He
- Department of Biochemistry and Molecular Biology and Institute for Biophysical Dynamics, Howard Hughes Medical Institute, University of Chicago, Chicago, Illinois
| | - Andrew W Duncan
- Department of Pathology, Pittsburgh Liver Research Center, McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pennsylvania.
| | - Kalpana Ghoshal
- Department of Pathology, The Ohio State University, Columbus, Ohio; Comprehensive Cancer Center, College of Medicine, The Ohio State University, Columbus, Ohio.
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7
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Wilkinson PD, Duncan AW. Differential Roles for Diploid and Polyploid Hepatocytes in Acute and Chronic Liver Injury. Semin Liver Dis 2021; 41:42-49. [PMID: 33764484 PMCID: PMC8056861 DOI: 10.1055/s-0040-1719175] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Hepatocytes are the primary functional cells of the liver that perform essential roles in homeostasis, regeneration, and injury. Most mammalian somatic cells are diploid and contain pairs of each chromosome, but there are also polyploid cells containing additional sets of chromosomes. Hepatocytes are among the best described polyploid cells, with polyploids comprising more than 25 and 90% of the hepatocyte population in humans and mice, respectively. Cellular and molecular mechanisms that regulate hepatic polyploidy have been uncovered, and in recent years, diploid and polyploid hepatocytes have been shown to perform specialized functions. Diploid hepatocytes accelerate liver regeneration induced by resection and may accelerate compensatory regeneration after acute injury. Polyploid hepatocytes protect the liver from tumor initiation in hepatocellular carcinoma and promote adaptation to tyrosinemia-induced chronic injury. This review describes how ploidy variations influence cellular activity and presents a model for context-specific functions for diploid and polyploid hepatocytes.
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Affiliation(s)
- Patrick D Wilkinson
- Division of Genetics, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Andrew W Duncan
- Department of Pathology, McGowan Institute for Regenerative Medicine, Pittsburgh Liver Research Center, University of Pittsburgh, Pittsburgh, Pennsylvania
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8
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SARS-CoV-2 related liver impairment - perception may not be the reality. J Hepatol 2020; 73:991-992. [PMID: 32454042 PMCID: PMC7255210 DOI: 10.1016/j.jhep.2020.05.025] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 05/14/2020] [Accepted: 05/16/2020] [Indexed: 12/11/2022]
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9
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Lin YH, Zhang S, Zhu M, Lu T, Chen K, Wen Z, Wang S, Xiao G, Luo D, Jia Y, Li L, MacConmara M, Hoshida Y, Singal A, Yopp A, Wang T, Zhu H. Mice With Increased Numbers of Polyploid Hepatocytes Maintain Regenerative Capacity But Develop Fewer Hepatocellular Carcinomas Following Chronic Liver Injury. Gastroenterology 2020; 158:1698-1712.e14. [PMID: 31972235 PMCID: PMC8902703 DOI: 10.1053/j.gastro.2020.01.026] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2019] [Revised: 12/24/2019] [Accepted: 01/02/2020] [Indexed: 01/07/2023]
Abstract
BACKGROUND & AIMS Thirty to 90% of hepatocytes contain whole-genome duplications, but little is known about the fates or functions of these polyploid cells or how they affect development of liver disease. We investigated the effects of continuous proliferative pressure, observed in chronically damaged liver tissues, on polyploid cells. METHODS We studied Rosa-rtTa mice (controls) and Rosa-rtTa;TRE-short hairpin RNA mice, which have reversible knockdown of anillin, actin binding protein (ANLN). Transient administration of doxycycline increases the frequency and degree of hepatocyte polyploidy without permanently altering levels of ANLN. Mice were then given diethylnitrosamine and carbon tetrachloride (CCl4) to induce mutations, chronic liver damage, and carcinogenesis. We performed partial hepatectomies to test liver regeneration and then RNA-sequencing to identify changes in gene expression. Lineage tracing was used to rule out repopulation from non-hepatocyte sources. We imaged dividing hepatocytes to estimate the frequency of mitotic errors during regeneration. We also performed whole-exome sequencing of 54 liver nodules from patients with cirrhosis to quantify aneuploidy, a possible outcome of polyploid cell divisions. RESULTS Liver tissues from control mice given CCl4 had significant increases in ploidy compared with livers from uninjured mice. Mice with knockdown of ANLN had hepatocyte ploidy above physiologic levels and developed significantly fewer liver tumors after administration of diethylnitrosamine and CCl4 compared with control mice. Increased hepatocyte polyploidy was not associated with altered regenerative capacity or tissue fitness, changes in gene expression, or more mitotic errors. Based on lineage-tracing experiments, non-hepatocytes did not contribute to liver regeneration in mice with increased polyploidy. Despite an equivalent rate of mitosis in hepatocytes of differing ploidies, we found no lagging chromosomes or micronuclei in mitotic polyploid cells. In nodules of human cirrhotic liver tissue, there was no evidence of chromosome-level copy number variations. CONCLUSIONS Mice with increased polyploid hepatocytes develop fewer liver tumors following chronic liver damage. Remarkably, polyploid hepatocytes maintain the ability to regenerate liver tissues during chronic damage without generating mitotic errors, and aneuploidy is not commonly observed in cirrhotic livers. Strategies to increase numbers of polypoid hepatocytes might be effective in preventing liver cancer.
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Affiliation(s)
- Yu-Hsuan Lin
- Children’s Research Institute, Departments of Pediatrics and Internal Medicine, Center for Regenerative Science and Medicine
| | - Shuyuan Zhang
- Children’s Research Institute, Departments of Pediatrics and Internal Medicine, Center for Regenerative Science and Medicine
| | - Min Zhu
- Children’s Research Institute, Departments of Pediatrics and Internal Medicine, Center for Regenerative Science and Medicine
| | - Tianshi Lu
- Children’s Research Institute, Departments of Pediatrics and Internal Medicine, Center for Regenerative Science and Medicine,Quantitative Biomedical Research Center, Department of Population and Data Sciences
| | - Kenian Chen
- Quantitative Biomedical Research Center, Department of Population and Data Sciences
| | - Zhuoyu Wen
- Quantitative Biomedical Research Center, Department of Population and Data Sciences
| | - Shidan Wang
- Quantitative Biomedical Research Center, Department of Population and Data Sciences
| | - Guanghua Xiao
- Quantitative Biomedical Research Center, Department of Population and Data Sciences
| | - Danni Luo
- Quantitative Biomedical Research Center, Department of Population and Data Sciences
| | - Yuemeng Jia
- Children’s Research Institute, Departments of Pediatrics and Internal Medicine, Center for Regenerative Science and Medicine
| | - Lin Li
- Children’s Research Institute, Departments of Pediatrics and Internal Medicine, Center for Regenerative Science and Medicine
| | | | | | | | | | - Tao Wang
- Quantitative Biomedical Research Center, Department of Population and Data Sciences,Kidney Cancer Program, Simmons Comprehensive Cancer Center,Center for the Genetics of Host Defense, University of Texas Southwestern Medical Center, Dallas, Texas
| | - Hao Zhu
- Children's Research Institute, Departments of Pediatrics and Internal Medicine, Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, Texas.
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10
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Monmeesil P, Fungfuang W, Tulayakul P, Pongchairerk U. The effects of astaxanthin on liver histopathology and expression of superoxide dismutase in rat aflatoxicosis. J Vet Med Sci 2019; 81:1162-1172. [PMID: 31270307 PMCID: PMC6715921 DOI: 10.1292/jvms.18-0690] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The metabolism of aflatoxin B1 (AFB1) generates reactive oxygen
species (ROS) that destroys hepatocytes. Meanwhile, astaxanthin (AX) is known to have
stronger antioxidative activity than other carotenoids. This study aimed to investigate
hepatoprotective role of AX from AFB1-induced toxicity in rat by
histopathological study and immunohistochemistry of Cu/Zn-SOD (SOD1) which acts as the
first enzyme in antioxidative reaction against cell injury from ROS. Twenty Wistar rats
were randomly divided into 4 groups. The control and AFB1 groups were gavaged
by water for 7 days followed by a single DMSO and 1 mg/kg AFB1, respectively.
The AXL+ AFB1 and AXH+ AFB1 groups were given of 5 mg/kg and 100
mg/kg AX for 7 days before 1 mg/kg AFB1 administration. The result showed
significantly elevated liver weight per 100 g body weight in AFB1 group. The
histopathological finding revealed vacuolar degeneration, necrosis, megalocytosis and
binucleation of hepatocytes with bile duct hyperplasia in AFB1 group. The
severities of pathological changes were sequentially reduced in AXL+AFB1 and
AXH+AFB1 groups. Most rats in AXH+AFB1 group owned hypertrophic
hepatocytes and atypical proliferation of cholangiocytes which are adaptive responses to
severe hepatocyte damage. The SOD1 expression was also significantly higher in
AXH+AFB1 group than solely treated AFB1 and AXL+AFB1
groups. In conclusion, AX alleviated AFB1-induced liver damage in rat by
stimulating SOD1 expression and transdifferentiation of cholangiocytes in dose dependent
manner.
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Affiliation(s)
- Poempool Monmeesil
- Department of Anatomy, Faculty of Veterinary Medicine, Kasetsart University, 50 Ngamwongwan Road, Ladyao, Jatuchak, Bangkok 10900, Thailand
| | - Wirasak Fungfuang
- Department of Zoology, Faculty of Science, Kasetsart University, 50 Ngamwongwan Road, Ladyao, Jatuchak, Bangkok 10900, Thailand
| | - Phitsanu Tulayakul
- Department of Veterinary Public Health, Faculty of Veterinary Medicine, Kasetsart University, Malaiman Road, Kamphaeng Saen, Nakhon Pathom 73140, Thailand
| | - Urai Pongchairerk
- Department of Anatomy, Faculty of Veterinary Medicine, Kasetsart University, 50 Ngamwongwan Road, Ladyao, Jatuchak, Bangkok 10900, Thailand
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11
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Wang MJ, Chen F, Lau JTY, Hu YP. Hepatocyte polyploidization and its association with pathophysiological processes. Cell Death Dis 2017; 8:e2805. [PMID: 28518148 PMCID: PMC5520697 DOI: 10.1038/cddis.2017.167] [Citation(s) in RCA: 89] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Revised: 03/01/2017] [Accepted: 03/14/2017] [Indexed: 12/14/2022]
Abstract
A characteristic cellular feature of the mammalian liver is the progressive polyploidization of the hepatocytes, where individual cells acquire more than two sets of chromosomes. Polyploidization results from cytokinesis failure that takes place progressively during the course of postnatal development. The proportion of polyploidy also increases with the aging process or with cellular stress such as surgical resection, toxic stimulation, metabolic overload, or oxidative damage, to involve as much as 90% of the hepatocytes in mice and 40% in humans. Hepatocyte polyploidization is generally considered an indicator of terminal differentiation and cellular senescence, and related to the dysfunction of insulin and p53/p21 signaling pathways. Interestingly, the high prevalence of hepatocyte polyploidization in the aged mouse liver can be reversed when the senescent hepatocytes are serially transplanted into young mouse livers. Here we review the current knowledge on the mechanism of hepatocytes polyploidization during postnatal growth, aging, and liver diseases. The biologic significance of polyploidization in senescent reversal, within the context of new ways to think of liver aging and liver diseases is considered.
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Affiliation(s)
- Min-Jun Wang
- Department of Cell Biology, Center for Stem Cell and Medicine, Second Military Medical University, Shanghai 200433, China
| | - Fei Chen
- Department of Cell Biology, Center for Stem Cell and Medicine, Second Military Medical University, Shanghai 200433, China
| | - Joseph T Y Lau
- Department of Molecular and Cellular Biology, Roswell Park Cancer Institute, Buffalo, NY 14263, USA
| | - Yi-Ping Hu
- Department of Cell Biology, Center for Stem Cell and Medicine, Second Military Medical University, Shanghai 200433, China
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12
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Losick VP, Jun AS, Spradling AC. Wound-Induced Polyploidization: Regulation by Hippo and JNK Signaling and Conservation in Mammals. PLoS One 2016; 11:e0151251. [PMID: 26958853 PMCID: PMC4784922 DOI: 10.1371/journal.pone.0151251] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Accepted: 02/25/2016] [Indexed: 12/13/2022] Open
Abstract
Tissue integrity and homeostasis often rely on the proliferation of stem cells or differentiated cells to replace lost, aged, or damaged cells. Recently, we described an alternative source of cell replacement- the expansion of resident, non-dividing diploid cells by wound-induced polyploidization (WIP). Here we show that the magnitude of WIP is proportional to the extent of cell loss using a new semi-automated assay with single cell resolution. Hippo and JNK signaling regulate WIP; unexpectedly however, JNK signaling through AP-1 limits rather than stimulates the level of Yki activation and polyploidization in the Drosophila epidermis. We found that polyploidization also quantitatively compensates for cell loss in a mammalian tissue, mouse corneal endothelium, where increased cell death occurs with age in a mouse model of Fuchs Endothelial Corneal Dystrophy (FECD). Our results suggest that WIP is an evolutionarily conserved homeostatic mechanism that maintains the size and synthetic capacity of adult tissues.
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Affiliation(s)
- Vicki P. Losick
- Department of Embryology, Carnegie Institution for Science, Howard Hughes Medical Institute, 3250 San Martin Dr., Baltimore, MD 21218, United States of America
| | - Albert S. Jun
- Wilmer Eye Institute, Johns Hopkins School of Medicine, 400 N. Broadway, Baltimore, MD 21231, United States of America
| | - Allan C. Spradling
- Department of Embryology, Carnegie Institution for Science, Howard Hughes Medical Institute, 3250 San Martin Dr., Baltimore, MD 21218, United States of America
- * E-mail:
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