1
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Liang T, Kong Y, Xue H, Wang W, Li C, Chen C. Mutations of RAS genes identified in acute myeloid leukemia affect glycerophospholipid metabolism pathway. Front Oncol 2023; 13:1280192. [PMID: 38033488 PMCID: PMC10682766 DOI: 10.3389/fonc.2023.1280192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2023] [Accepted: 10/23/2023] [Indexed: 12/02/2023] Open
Abstract
Background Acute myeloid leukemia (AML) is a malignant disease originating from myeloid hematopoietic stem cells. Recent studies have shown that certain gene mutations promote tumor cell survival and affect the prognosis of patients by affecting metabolic mechanisms in tumor cells. RAS gene mutations are prevalent in AML, and the RAS signaling pathway is closely related to many metabolic pathways. However, the effects of different RAS gene mutations on AML cell metabolism are unclear. Objectives The main purpose of this study was to explore the effect of RAS gene mutation on the metabolic pathway of tumor cells. Methods In this study, we first used a retrovirus carrying a mutant gene to prepare Ba/F3 cell lines with RAS gene mutations, and then compared full-transcriptome data of Ba/F3 cells before and after RAS gene mutation and found that differentially expressed genes after NRASQ61K and KRASG12V mutation. Results We found a total of 1899 differentially expressed genes after NRASQ61K and KRASG12V mutation. 1089 of these genes were involved in metabolic processes, of which 167 genes were enriched in metabolism-related pathways. In metabolism-related pathways, differential genes were associated with the lipid metabolism pathway. Moreover, by comparing groups, we found that the expression of the DGKzeta and PLA2G4A genes in the glycerophospholipid metabolism pathway was significantly upregulated. Conclusion In conclusion, our study revealed that RAS gene mutation is closely related to the glycerophospholipid metabolism pathway in Ba/F3 cells, which may contribute to new precision therapy strategies and the development and application of new therapeutic drugs for AML.
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Affiliation(s)
- Tianqi Liang
- Pediatric Hematology Laboratory, Division of Hematology/Oncology, Department of Pediatrics, The Seventh Affiliated Hospital of Sun Yat-Sen University, Shenzhen, Guangdong, China
| | - Yanxiang Kong
- Department of Reproductive Medicine, The Seventh Affiliated Hospital, Sun Yat-sen University, Shenzhen, Guangdong, China
| | - Hongman Xue
- Pediatric Hematology Laboratory, Division of Hematology/Oncology, Department of Pediatrics, The Seventh Affiliated Hospital of Sun Yat-Sen University, Shenzhen, Guangdong, China
| | - Wenqing Wang
- Pediatric Hematology Laboratory, Division of Hematology/Oncology, Department of Pediatrics, The Seventh Affiliated Hospital of Sun Yat-Sen University, Shenzhen, Guangdong, China
| | - Chunmou Li
- Pediatric Hematology Laboratory, Division of Hematology/Oncology, Department of Pediatrics, The Seventh Affiliated Hospital of Sun Yat-Sen University, Shenzhen, Guangdong, China
| | - Chun Chen
- Pediatric Hematology Laboratory, Division of Hematology/Oncology, Department of Pediatrics, The Seventh Affiliated Hospital of Sun Yat-Sen University, Shenzhen, Guangdong, China
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2
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Zhang Y, Liu Y, Sun J, Zhang W, Guo Z, Ma Q. Arachidonic acid metabolism in health and disease. MedComm (Beijing) 2023; 4:e363. [PMID: 37746665 PMCID: PMC10511835 DOI: 10.1002/mco2.363] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2023] [Revised: 08/13/2023] [Accepted: 08/17/2023] [Indexed: 09/26/2023] Open
Abstract
Arachidonic acid (AA), an n-6 essential fatty acid, is a major component of mammalian cells and can be released by phospholipase A2. Accumulating evidence indicates that AA plays essential biochemical roles, as it is the direct precursor of bioactive lipid metabolites of eicosanoids such as prostaglandins, leukotrienes, and epoxyeicosatrienoic acid obtained from three distinct enzymatic metabolic pathways: the cyclooxygenase pathway, lipoxygenase pathway, and cytochrome P450 pathway. AA metabolism is involved not only in cell differentiation, tissue development, and organ function but also in the progression of diseases, such as hepatic fibrosis, neurodegeneration, obesity, diabetes, and cancers. These eicosanoids are generally considered proinflammatory molecules, as they can trigger oxidative stress and stimulate the immune response. Therefore, interventions in AA metabolic pathways are effective ways to manage inflammatory-related diseases in the clinic. Currently, inhibitors targeting enzymes related to AA metabolic pathways are an important area of drug discovery. Moreover, many advances have also been made in clinical studies of AA metabolic inhibitors in combination with chemotherapy and immunotherapy. Herein, we review the discovery of AA and focus on AA metabolism in relation to health and diseases. Furthermore, inhibitors targeting AA metabolism are summarized, and potential clinical applications are discussed.
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Affiliation(s)
- Yiran Zhang
- Department of Orthopedic SurgeryOrthopedic Oncology InstituteThe Second Affiliated Hospital of Air Force Medical UniversityXi'anChina
| | - Yingxiang Liu
- Department of Orthopedic SurgeryOrthopedic Oncology InstituteThe Second Affiliated Hospital of Air Force Medical UniversityXi'anChina
| | - Jin Sun
- Department of Orthopedic SurgeryOrthopedic Oncology InstituteThe Second Affiliated Hospital of Air Force Medical UniversityXi'anChina
| | - Wei Zhang
- Department of PathologyThe Second Affiliated Hospital of Air Force Medical UniversityXi'anChina
| | - Zheng Guo
- Department of Orthopedic SurgeryOrthopedic Oncology InstituteThe Second Affiliated Hospital of Air Force Medical UniversityXi'anChina
| | - Qiong Ma
- Department of Orthopedic SurgeryOrthopedic Oncology InstituteThe Second Affiliated Hospital of Air Force Medical UniversityXi'anChina
- Department of PathologyThe Second Affiliated Hospital of Air Force Medical UniversityXi'anChina
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3
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Khan SA, Ilies MA. The Phospholipase A2 Superfamily: Structure, Isozymes, Catalysis, Physiologic and Pathologic Roles. Int J Mol Sci 2023; 24:ijms24021353. [PMID: 36674864 PMCID: PMC9862071 DOI: 10.3390/ijms24021353] [Citation(s) in RCA: 27] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 12/23/2022] [Accepted: 01/06/2023] [Indexed: 01/13/2023] Open
Abstract
The phospholipase A2 (PLA2) superfamily of phospholipase enzymes hydrolyzes the ester bond at the sn-2 position of the phospholipids, generating a free fatty acid and a lysophospholipid. The PLA2s are amphiphilic in nature and work only at the water/lipid interface, acting on phospholipid assemblies rather than on isolated single phospholipids. The superfamily of PLA2 comprises at least six big families of isoenzymes, based on their structure, location, substrate specificity and physiologic roles. We are reviewing the secreted PLA2 (sPLA2), cytosolic PLA2 (cPLA2), Ca2+-independent PLA2 (iPLA2), lipoprotein-associated PLA2 (LpPLA2), lysosomal PLA2 (LPLA2) and adipose-tissue-specific PLA2 (AdPLA2), focusing on the differences in their structure, mechanism of action, substrate specificity, interfacial kinetics and tissue distribution. The PLA2s play important roles both physiologically and pathologically, with their expression increasing significantly in diseases such as sepsis, inflammation, different cancers, glaucoma, obesity and Alzheimer's disease, which are also detailed in this review.
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Mahammad N, Ashcroft FJ, Feuerherm AJ, Elsaadi S, Vandsemb EN, Børset M, Johansen B. Inhibition of Cytosolic Phospholipase A2α Induces Apoptosis in Multiple Myeloma Cells. Molecules 2021; 26:molecules26247447. [PMID: 34946532 PMCID: PMC8705991 DOI: 10.3390/molecules26247447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 11/26/2021] [Accepted: 11/30/2021] [Indexed: 11/16/2022] Open
Abstract
Cytosolic phospholipase A2α (cPLA2α) is the rate-limiting enzyme in releasing arachidonic acid and biosynthesis of its derivative eicosanoids. Thus, the catalytic activity of cPLA2α plays an important role in cellular metabolism in healthy as well as cancer cells. There is mounting evidence suggesting that cPLA2α is an interesting target for cancer treatment; however, it is unclear which cancers are most relevant for further investigation. Here we report the relative expression of cPLA2α in a variety of cancers and cancer cell lines using publicly available datasets. The profiling of a panel of cancer cell lines representing different tissue origins suggests that hematological malignancies are particularly sensitive to the growth inhibitory effect of cPLA2α inhibition. Several hematological cancers and cancer cell lines overexpressed cPLA2α, including multiple myeloma. Multiple myeloma is an incurable hematological cancer of plasma cells in the bone marrow with an emerging requirement of therapeutic approaches. We show here that two cPLA2α inhibitors AVX420 and AVX002, significantly and dose-dependently reduced the viability of multiple myeloma cells and induced apoptosis in vitro. Our findings implicate cPLA2α activity in the survival of multiple myeloma cells and support further studies into cPLA2α as a potential target for treating hematological cancers, including multiple myeloma.
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Affiliation(s)
- Nur Mahammad
- Department of Biology, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway; (F.J.A.); (A.J.F.)
- Correspondence: (N.M.); (B.J.)
| | - Felicity J. Ashcroft
- Department of Biology, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway; (F.J.A.); (A.J.F.)
| | - Astrid J. Feuerherm
- Department of Biology, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway; (F.J.A.); (A.J.F.)
| | - Samah Elsaadi
- Center for Myeloma Research, Department of Clinical and Molecular Medicine, Faculty of Medicine and Health Science, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway; (S.E.); (E.N.V.); (M.B.)
| | - Esten N. Vandsemb
- Center for Myeloma Research, Department of Clinical and Molecular Medicine, Faculty of Medicine and Health Science, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway; (S.E.); (E.N.V.); (M.B.)
| | - Magne Børset
- Center for Myeloma Research, Department of Clinical and Molecular Medicine, Faculty of Medicine and Health Science, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway; (S.E.); (E.N.V.); (M.B.)
- Department of Immunology and Transfusion Medicine, St. Olav’s University Hospital, 7491 Trondheim, Norway
| | - Berit Johansen
- Department of Biology, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway; (F.J.A.); (A.J.F.)
- Correspondence: (N.M.); (B.J.)
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Zhang K, Zhang M, Luo Z, Wen Z, Yan X. The dichotomous role of TGF-β in controlling liver cancer cell survival and proliferation. J Genet Genomics 2020; 47:497-512. [PMID: 33339765 DOI: 10.1016/j.jgg.2020.09.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 09/14/2020] [Accepted: 09/29/2020] [Indexed: 12/24/2022]
Abstract
Hepatocellular carcinoma (HCC) is the major form of primary liver cancer and one of the most prevalent and life-threatening malignancies globally. One of the hallmarks in HCC is the sustained cell survival and proliferative signals, which are determined by the balance between oncogenes and tumor suppressors. Transforming growth factor beta (TGF-β) is an effective growth inhibitor of epithelial cells including hepatocytes, through induction of cell cycle arrest, apoptosis, cellular senescence, or autophagy. The antitumorigenic effects of TGF-β are bypassed during liver tumorigenesis via multiple mechanisms. Furthermore, along with malignant progression, TGF-β switches to promote cancer cell survival and proliferation. This dichotomous nature of TGF-β is one of the barriers to therapeutic targeting in liver cancer. Thereafter, understanding the underlying molecular mechanisms is a prerequisite for discovering novel antitumor drugs that may specifically disable the growth-promoting branch of TGF-β signaling or restore its tumor-suppressive arm. This review summarizes how TGF-β inhibits or promotes liver cancer cell survival and proliferation, highlighting the functional switch mechanisms during the process.
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Affiliation(s)
- Kegui Zhang
- School of Biological Engineering, Huainan Normal University, Huainan, 232001, China
| | - Meiping Zhang
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Nanchang University, Nanchang, 330006, China
| | - Zhijun Luo
- School of Basic Medical Sciences, Nanchang University, Nanchang 330006, China
| | - Zhili Wen
- Department of Gastroenterology, The Second Affiliated Hospital of Nanchang University, Nanchang, 330006, China.
| | - Xiaohua Yan
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Nanchang University, Nanchang, 330006, China; Institute of Biomedical Sciences, Nanchang University Medical College, Nanchang, 330031, China.
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6
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Peng Z, Chang Y, Fan J, Ji W, Su C. Phospholipase A2 superfamily in cancer. Cancer Lett 2020; 497:165-177. [PMID: 33080311 DOI: 10.1016/j.canlet.2020.10.021] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 10/11/2020] [Accepted: 10/14/2020] [Indexed: 12/12/2022]
Abstract
Phospholipase A2 enzymes (PLA2s) comprise a superfamily that is generally divided into six subfamilies known as cytosolic PLA2s (cPLA2s), calcium-independent PLA2s (iPLA2s), secreted PLA2s (sPLA2s), lysosomal PLA2s, platelet-activating factor (PAF) acetylhydrolases, and adipose specific PLA2s. Each subfamily consists of several isozymes that possess PLA2 activity. The first three PLA2 subfamilies play important roles in inflammation-related diseases and cancer. In this review, the roles of well-studied enzymes sPLA2-IIA, cPLA2α and iPLA2β in carcinogenesis and cancer development were discussed. sPLA2-IIA seems to play conflicting roles and can act as a tumor suppressor or a tumor promoter according to the cancer type, but cPLA2α and iPLA2β play protumorigenic role in most cancers. The mechanisms of PLA2-mediated signal transduction and crosstalk between cancer cells and endothelial cells in the tumor microenvironment are described. Moreover, the mechanisms by which PLA2s mediate lipid reprogramming and glycerophospholipid remodeling in cancer cells are illustrated. PLA2s as the upstream regulators of the arachidonic acid cascade are generally high expressed and activated in various cancers. Therefore, they can be considered as potential pharmacological targets and biomarkers in cancer. The detailed information summarized in this review may aid in understanding the roles of PLA2s in cancer, and provide new clues for the development of novel agents and strategies for tumor prevention and treatment.
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Affiliation(s)
- Zhangxiao Peng
- Department of Molecular Oncology, Eastern Hepatobiliary Surgical Hospital & National Center for Liver Cancer, Navy Military Medical University, Shanghai, 200438, China.
| | - Yanxin Chang
- Department of Biliary Tract Surgery IV, Eastern Hepatobiliary Surgical Hospital, Navy Military Medical University, Shanghai, 200438, China.
| | - Jianhui Fan
- Mengchao Hepatobiliary Hospital, Fujian Medical University, Fuzhou, 350025, Fujian Province, China.
| | - Weidan Ji
- Department of Molecular Oncology, Eastern Hepatobiliary Surgical Hospital & National Center for Liver Cancer, Navy Military Medical University, Shanghai, 200438, China.
| | - Changqing Su
- Department of Molecular Oncology, Eastern Hepatobiliary Surgical Hospital & National Center for Liver Cancer, Navy Military Medical University, Shanghai, 200438, China.
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7
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The Many Roles of Cell Adhesion Molecules in Hepatic Fibrosis. Cells 2019; 8:cells8121503. [PMID: 31771248 PMCID: PMC6952767 DOI: 10.3390/cells8121503] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 11/17/2019] [Accepted: 11/18/2019] [Indexed: 01/09/2023] Open
Abstract
Fibrogenesis is a progressive scarring event resulting from disrupted regular wound healing due to repeated tissue injury and can end in organ failure, like in liver cirrhosis. The protagonists in this process, either liver-resident cells or patrolling leukocytes attracted to the site of tissue damage, interact with each other by soluble factors but also by direct cell–cell contact mediated by cell adhesion molecules. Since cell adhesion molecules also support binding to the extracellular matrix, they represent excellent biosensors, which allow cells to modulate their behavior based on changes in the surrounding microenvironment. In this review, we focus on selectins, cadherins, integrins and members of the immunoglobulin superfamily of adhesion molecules as well as some non-classical cell adhesion molecules in the context of hepatic fibrosis. We describe their liver-specific contributions to leukocyte recruitment, cell differentiation and survival, matrix remodeling or angiogenesis and touch on their suitability as targets in antifibrotic therapies.
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8
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Contextual Regulation of TGF-β Signaling in Liver Cancer. Cells 2019; 8:cells8101235. [PMID: 31614569 PMCID: PMC6829617 DOI: 10.3390/cells8101235] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 10/09/2019] [Accepted: 10/10/2019] [Indexed: 02/06/2023] Open
Abstract
Primary liver cancer is one of the leading causes for cancer-related death worldwide. Transforming growth factor beta (TGF-β) is a pleiotropic cytokine that signals through membrane receptors and intracellular Smad proteins, which enter the nucleus upon receptor activation and act as transcription factors. TGF-β inhibits liver tumorigenesis in the early stage by inducing cytostasis and apoptosis, but promotes malignant progression in more advanced stages by enhancing cancer cell survival, EMT, migration, invasion and finally metastasis. Understanding the molecular mechanisms underpinning the multi-faceted roles of TGF-β in liver cancer has become a persistent pursuit during the last two decades. Contextual regulation fine-tunes the robustness, duration and plasticity of TGF-β signaling, yielding versatile albeit specific responses. This involves multiple feedback and feed-forward regulatory loops and also the interplay between Smad signaling and non-Smad pathways. This review summarizes the known regulatory mechanisms of TGF-β signaling in liver cancer, and how they channel, skew and even switch the actions of TGF-β during cancer progression.
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9
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Ranjpour M, Wajid S, Jain SK. Elevated Expression of Cytosolic Phospholipase A2 Delta Is Associated with Lipid Metabolism Dysregulation during Hepatocellular Carcinoma Progression. CELL JOURNAL 2019; 22:17-22. [PMID: 31606962 PMCID: PMC6791066 DOI: 10.22074/cellj.2020.6527] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Accepted: 02/04/2019] [Indexed: 12/15/2022]
Abstract
Objective Liver cancer is the third rank amongst the common malignancies, causing maximum death in the patients
diagnosed with cancers. Currently available biomarkers are not enough sensitive for early diagnosis of hepatocellular
carcinoma (HCC). This makes difficult management of HCC. With the aim of finding new generation of proteomic-based
biomarkers, the represented study was designed to characterize the differentially expressed proteins at different stages
of HCC initiation and at progression. This could lead to find potential biomarkers for early detection of HCC.
Materials and Methods In this experimental study, we report induction of HCC by administrating chemical carcinogens
in male Wistar rats. Disease progression was monitored by histological evaluation. Serum proteomic analyses such as
2 dimensional (2D)-electrophoresis, MALDI-TOF-MS/MS and Western blot have been used to analyze and characterize
the differentially expressed proteins during HCC development.
Results HCC initiation and tumorigenesis were observed at one and four months post carcinogen treatment,
respectively. One of the differentially-expressed proteins, namely, cytosolic phospholipase A2delta was significantly
up-regulated at very early stage of HCC development. Its expression continued to increase during cancer progression
and hepatotumorigenesis stages. Its elevated expression has been confirmed by Western blot analysis. Consistent to
this, analyses of the sera in the clinically confirmed liver cancer patients showed elevated expression of this protein,
further validating our experimental results.
Conclusion This study suggests that elevation in the expression of cytosolic phospholipase A2delta is associated with
progression of HCC.
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Affiliation(s)
- Maryam Ranjpour
- Department of Biotechnology, School of Chemical and Life Sciences, Jamia Hamdard, New Delhi, India
| | - Saima Wajid
- Department of Biotechnology, School of Chemical and Life Sciences, Jamia Hamdard, New Delhi, India
| | - Swatantra Kumar Jain
- Department of Medical Biochemistry, HIMSR, Jamia Hamdard, New Delhi, India. Electronic Address:
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Zhang J, Han C, Ungerleider N, Chen W, Song K, Wang Y, Kwon H, Ma W, Wu T. A Transforming Growth Factor-β and H19 Signaling Axis in Tumor-Initiating Hepatocytes That Regulates Hepatic Carcinogenesis. Hepatology 2019; 69:1549-1563. [PMID: 30014520 PMCID: PMC6335184 DOI: 10.1002/hep.30153] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Accepted: 06/23/2018] [Indexed: 02/06/2023]
Abstract
Functions of transforming growth factor-β (TGF-β) in the liver vary depending on specific cell types and their temporal response to TGF-β during different stages of hepatocarcinogenesis (HCG). Through analysis of tumor tissues from hepatocellular carcinoma (HCC) patients, we were able to cluster hepatic epithelial cell-derived TGF-β gene signatures in association with distinct clinical prognoses. To delineate the role of hepatic epithelial TGF-β signaling in HCC development, we used an experimental system in which tumor-initiating hepatocytes (TICs) were isolated from TGF-β receptor II floxed mice (Tgfbr2fl/fl ) and transplanted into syngeneic C57BL/6J mice by splenic injection. Recipient mice were then administered Cre-expressing adenovirus (Ad-Cre) to inactivate Tgfbr2 in transplanted TICs. After latency, Tgfbr2-inactivated TICs formed larger and more tumor nodules in recipient livers compared to TICs without Tgfbr2 inactivation. In vitro analyses revealed that treatment of cultured TICs with TGF-β inhibited expression of progenitor cell factors (including SRY (sex determining region Y)-box 2 [Sox2]). RNA sequencing (RNA-seq) analysis identified H19 as one of the most up-regulated long noncoding RNA (lncRNA) in association with Tgfbr2 inactivation in TICs. Tgfbr2 inactivation by Ad-Cre led to a 5-fold increase of H19 expression in TICs. Accordingly, TGF-β treatment reduced H19 expression. We observed that forced overexpression of Sox2 in TICs increased transcription of H19, whereas knockdown of Sox2 decreased it. Furthermore, depletion of H19 reduced the progenitor property of TICs in vitro and decreased their tumorigenic potential in vivo. Finally, we observed a low level of H19 mRNA expression in human HCC tissues from patients with the epithelial TGF-β gene signature in association with favorable prognosis. Conclusion: Our findings describe a TGF-β and H19 signaling axis by Sox2 in TICs that importantly regulates HCG.
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Affiliation(s)
- Jinqiang Zhang
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, New Orleans, LA
| | - Chang Han
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, New Orleans, LA
| | - Nathan Ungerleider
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, New Orleans, LA
| | - Weina Chen
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, New Orleans, LA
| | - Kyoungsub Song
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, New Orleans, LA
| | - Ying Wang
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, New Orleans, LA
| | - Hyunjoo Kwon
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, New Orleans, LA
| | - Wenbo Ma
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, New Orleans, LA
| | - Tong Wu
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, New Orleans, LA
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11
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Greenhalgh SN, Matchett KP, Taylor RS, Huang K, Li JT, Saeteurn K, Donnelly MC, Simpson EEM, Pollack JL, Atakilit A, Simpson KJ, Maher JJ, Iredale JP, Sheppard D, Henderson NC. Loss of Integrin αvβ8 in Murine Hepatocytes Accelerates Liver Regeneration. THE AMERICAN JOURNAL OF PATHOLOGY 2019; 189:258-271. [PMID: 30448409 PMCID: PMC6360354 DOI: 10.1016/j.ajpath.2018.10.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Revised: 09/14/2018] [Accepted: 10/10/2018] [Indexed: 02/08/2023]
Abstract
Recent fate-mapping studies in mice have provided substantial evidence that mature adult hepatocytes are a major source of new hepatocytes after liver injury. In other systems, integrin αvβ8 has a major role in activating transforming growth factor (TGF)-β, a potent inhibitor of hepatocyte proliferation. We hypothesized that depletion of hepatocyte integrin αvβ8 would increase hepatocyte proliferation and accelerate liver regeneration after injury. Using Itgb8flox/flox;Alb-Cre mice to deplete hepatocyte αvβ8, after partial hepatectomy, hepatocyte proliferation and liver-to-body weight ratio were significantly increased in Itgb8flox/flox;Alb-Cre mice compared with control mice. Antibody-mediated blockade of hepatocyte αvβ8 in vitro, with assessment of TGF-β signaling pathways by real-time quantitative PCR array, supported the hypothesis that integrin αvβ8 inhibition alters hepatocyte TGF-β signaling toward a pro-regenerative phenotype. A diethylnitrosamine-induced model of hepatocellular carcinoma, used to examine the possibility that this pro-proliferative phenotype might be oncogenic, revealed no difference in either tumor number or size between Itgb8flox/flox;Alb-Cre and control mice. Immunohistochemistry for integrin αvβ8 in healthy and injured human liver demonstrated that human hepatocytes express integrin αvβ8. Depletion of hepatocyte integrin αvβ8 results in increased hepatocyte proliferation and accelerated liver regeneration after partial hepatectomy in mice. These data demonstrate that targeting integrin αvβ8 may represent a promising therapeutic strategy to drive liver regeneration in patients with a broad range of liver diseases.
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Affiliation(s)
- Stephen N Greenhalgh
- Centre for Inflammation Research, The Queen's Medical Research Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Kylie P Matchett
- Centre for Inflammation Research, The Queen's Medical Research Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Richard S Taylor
- Centre for Inflammation Research, The Queen's Medical Research Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Katherine Huang
- Lung Biology Center, Department of Medicine, University of California, San Francisco, San Francisco, California
| | - John T Li
- Lung Biology Center, Department of Medicine, University of California, San Francisco, San Francisco, California
| | - Koy Saeteurn
- Lung Biology Center, Department of Medicine, University of California, San Francisco, San Francisco, California
| | - Mhairi C Donnelly
- Department of Hepatology, Scottish Liver Transplant Unit and University of Edinburgh, Royal Infirmary of Edinburgh, Edinburgh, United Kingdom
| | - Eilidh E M Simpson
- Centre for Inflammation Research, The Queen's Medical Research Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Joshua L Pollack
- Lung Biology Center, Department of Medicine, University of California, San Francisco, San Francisco, California
| | - Amha Atakilit
- Department of Pathology, University of California, San Francisco, San Francisco, California
| | - Kenneth J Simpson
- Department of Hepatology, Scottish Liver Transplant Unit and University of Edinburgh, Royal Infirmary of Edinburgh, Edinburgh, United Kingdom
| | - Jacquelyn J Maher
- Liver Center, Department of Medicine, University of California, San Francisco, San Francisco, California
| | - John P Iredale
- Centre for Inflammation Research, The Queen's Medical Research Institute, University of Edinburgh, Edinburgh, United Kingdom; Senate House, University of Bristol, Bristol, United Kingdom
| | - Dean Sheppard
- Lung Biology Center, Department of Medicine, University of California, San Francisco, San Francisco, California
| | - Neil C Henderson
- Centre for Inflammation Research, The Queen's Medical Research Institute, University of Edinburgh, Edinburgh, United Kingdom; Lung Biology Center, Department of Medicine, University of California, San Francisco, San Francisco, California.
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12
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Li ZJ, Chen W, Jiang H, Li XY, Zhu SN, Liu XH. Effects of Postoperative Parenteral Nutrition Enhanced by Multivitamin on Metabolic Phenotype in Postoperative Gastric Cancer Patients. Mol Nutr Food Res 2018; 62:e1700757. [PMID: 29710380 DOI: 10.1002/mnfr.201700757] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2017] [Revised: 04/10/2018] [Indexed: 12/17/2022]
Abstract
SCOPE To investigate the effects of postoperative parenteral nutrition (PN) with multivitamins supplementation on oxidative stress and metabolism. METHODS AND RESULTS The participants are randomly assigned in a 1:1 ratio to groups: total nutrient admixture (TNA) + multivitamin (n = 14, Group A) and TNA + normal saline (n = 16, Group B). The levels of blood vitamins, ILs, and MDA are assessed and the dysregulation of metabolism is analyzed using nontargeted metabolite profiling. The degree of postoperative stress in Group A is significantly lower than that in Group B by analyzing changes in the levels of IL-8 and MDA. A set of 43 features are qualified to have a variable importance parameter score of >1.5 of a partial least-squares discriminate analysis model and fold change of >1.5 at p-value <0.05 between Groups A and B. The principal metabolic alternations in Group A include increased tricarboxylic acid cycle and ketogenesis with reduced plasma-free amino acids. Backing the results of clinical biomarkers, increased levels of antioxidative molecules, together with decreased levels of inflammatory related polyunsaturated fatty acids, are observed. CONCLUSION Postoperative PN enhanced by multivitamins can alleviate traumatic stress and improve metabolic transition from catabolism to anabolism in gastric cancer patients.
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Affiliation(s)
- Zi-Jian Li
- Department of Parenteral and Enteral Nutrition, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, No. 1 Shuaifuyuan, Dongcheng District, Beijing, 100730, China
| | - Wei Chen
- Department of Parenteral and Enteral Nutrition, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, No. 1 Shuaifuyuan, Dongcheng District, Beijing, 100730, China
| | - Hua Jiang
- Department of Parenteral and Enteral Nutrition, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, No. 1 Shuaifuyuan, Dongcheng District, Beijing, 100730, China.,Metabolomics and Multidisciplinary Laboratory for Trauma Research, Institute for Emergency and Disaster Medicine, Sichuan Provincial People's Hospital, Sichuan Academy of Medical Sciences, Chengdu, Sichuan, 6100072, China
| | - Xiao-Yi Li
- Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100730, China
| | - Sai-Nan Zhu
- Statistics Department, Peking University First Hospital, Beijing, 100034, China
| | - Xiao-Hui Liu
- Technology Center for Protein Sciences, Tsinghua University, Beijing, 100084, China
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13
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Yang X, Fujisawa M, Yoshimura T, Ohara T, Sato M, Mino M, San TH, Gao T, Kunkel SL, Matsukawa A. Spred2 Deficiency Exacerbates D-Galactosamine/Lipopolysaccharide -induced Acute Liver Injury in Mice via Increased Production of TNFα. Sci Rep 2018; 8:188. [PMID: 29317674 PMCID: PMC5760641 DOI: 10.1038/s41598-017-18380-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 12/08/2017] [Indexed: 12/21/2022] Open
Abstract
Acute liver injury (ALI) is characterized by hepatocyte damage and inflammation. In the present study, we examined whether the absence of Sprouty-related EVH1-domain-containing protein 2 (Spred2), a negative regulator of the Ras/Raf/ERK/MAPK pathway, influences ALI induced by D-galactosamine (D-GalN) and lipopolysaccharide (LPS). Compared to wild-type mice, Spred2−/− mice developed exacerbated liver injury represented by enhanced hepatocyte damage and inflammation. Enhanced ERK activation was observed in Spred2−/−-livers, and the MEK/ERK inhibitor U0126 ameliorated ALI. Hepatic tumour necrosis factor α (TNFα) and interleukin (IL)-1β levels were increased in Spred-2−/−-livers, and the neutralization of TNFα dramatically ameliorated ALI, which was associated with decreased levels of endogenous TNFα and IL-1β. When mice were challenged with D-GalN and TNFα, much severer ALI was observed in Spred2−/− mice with significant increases in endogenous TNFα and IL-1β in the livers. Immunohistochemically, Kupffer cells were found to produce TNFα, and isolated Kupffer cells from Spred2−/− mice produced significantly higher levels of TNFα than those from wild-type mice after LPS stimulation, which was significantly decreased by U0126. These results suggest that Spred2 negatively regulates D-GalN/LPS-induced ALI under the control of TNFα in Kupffer cells. Spred2 may present a therapeutic target for the treatment of ALI.
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Affiliation(s)
- Xu Yang
- Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Masayoshi Fujisawa
- Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Teizo Yoshimura
- Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Toshiaki Ohara
- Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Miwa Sato
- Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Megumi Mino
- Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Thar Htet San
- Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Tong Gao
- Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
| | - Steven L Kunkel
- Department of Pathology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Akihiro Matsukawa
- Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan.
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Fu H, He Y, Qi L, Chen L, Luo Y, Chen L, Li Y, Zhang N, Guo H. cPLA2α activates PI3K/AKT and inhibits Smad2/3 during epithelial-mesenchymal transition of hepatocellular carcinoma cells. Cancer Lett 2017. [PMID: 28649002 DOI: 10.1016/j.canlet.2017.06.022] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Cytosolic phospholipase A2α (cPLA2α), a key phospholipase that regulates lipid metabolism, plays an important role in tumor progression. In the present study of hepatocellular carcinoma (HCC), cPLA2α was overexpressed in highly metastatic HCC cell lines. Immunohistochemical staining showed increased levels of cPLA2α at the invasive edges of HCC, and a clinicopathological analysis of samples from 111 patients revealed that its expression level was linked with micro-vascular invasion and cirrhosis. Knockdown of cPLA2α inhibited migration, probably due to its role in actin polymerization. Overexpression of cPLA2α promoted cell migration and invasion. Based on the mechanistic analysis, our data suggested that cPLA2α mediate epidermal growth factor (EGF) induced epithelial-mesenchymal transition (EMT) through PI3K/AKT/ERK pathway. cPLA2α activity was required for the transforming growth factor-(TGF)-β-induced EMT. However, cPLA2α inhibited Smad2/3 activation and promoted the activation of the PI3K/AKT/ERK pathway. A xenograft tumor transplant model confirmed the role of cPLA2α in HCC invasion and metastasis. Based on the mechanistic analysis, cPLA2α mediated both EGF- and TGF-β-induced EMT, which are essential for HCC metastasis. cPLA2α is a potentially target for novel therapies of HCC.
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Affiliation(s)
- Hui Fu
- Department of Tumor Cell Biology, Tianjin Medical University Cancer Institute and Hospital, Tianjin, 300060, China; The Key Laboratory of Tianjin Cancer Prevention and Treatment, National Clinical Research Center for Cancer, Tianjin, 300060, China; Tianjin University of Traditional Chinese Medicine, Tianjin, 300193, China
| | - Yuchao He
- Department of Tumor Cell Biology, Tianjin Medical University Cancer Institute and Hospital, Tianjin, 300060, China; The Key Laboratory of Tianjin Cancer Prevention and Treatment, National Clinical Research Center for Cancer, Tianjin, 300060, China
| | - Lisha Qi
- Department of Pathology, Tianjin Medical University Cancer Institute and Hospital, Tianjin, 300060, China; The Key Laboratory of Tianjin Cancer Prevention and Treatment, National Clinical Research Center for Cancer, Tianjin, 300060, China
| | - Lu Chen
- Department of Tumor Cell Biology, Tianjin Medical University Cancer Institute and Hospital, Tianjin, 300060, China; The Key Laboratory of Tianjin Cancer Prevention and Treatment, National Clinical Research Center for Cancer, Tianjin, 300060, China
| | - Yi Luo
- Department of Tumor Cell Biology, Tianjin Medical University Cancer Institute and Hospital, Tianjin, 300060, China; The Key Laboratory of Tianjin Cancer Prevention and Treatment, National Clinical Research Center for Cancer, Tianjin, 300060, China
| | - Liwei Chen
- Department of Tumor Cell Biology, Tianjin Medical University Cancer Institute and Hospital, Tianjin, 300060, China; The Key Laboratory of Tianjin Cancer Prevention and Treatment, National Clinical Research Center for Cancer, Tianjin, 300060, China
| | - Yongmei Li
- Department of Pathogen Biology, School of Basic Medical Sciences, Tianjin Medical University, Tianjin, China
| | - Ning Zhang
- Department of Tumor Cell Biology, Tianjin Medical University Cancer Institute and Hospital, Tianjin, 300060, China; The Key Laboratory of Tianjin Cancer Prevention and Treatment, National Clinical Research Center for Cancer, Tianjin, 300060, China.
| | - Hua Guo
- Department of Tumor Cell Biology, Tianjin Medical University Cancer Institute and Hospital, Tianjin, 300060, China; The Key Laboratory of Tianjin Cancer Prevention and Treatment, National Clinical Research Center for Cancer, Tianjin, 300060, China.
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Yao L, Chen W, Song K, Han C, Gandhi CR, Lim K, Wu T. 15-hydroxyprostaglandin dehydrogenase (15-PGDH) prevents lipopolysaccharide (LPS)-induced acute liver injury. PLoS One 2017; 12:e0176106. [PMID: 28423012 PMCID: PMC5397067 DOI: 10.1371/journal.pone.0176106] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Accepted: 04/05/2017] [Indexed: 12/23/2022] Open
Abstract
The NAD+-dependent 15-hydroxyprostaglandin dehydrogenase (15-PGDH) catalyzes the oxidation of the 15(S)-hydroxyl group of prostaglandin E2 (PGE2), converting the pro-inflammatory PGE2 to the anti-inflammatory 15-keto-PGE2 (an endogenous ligand for peroxisome proliferator-activated receptor-gamma [PPAR-γ]). To evaluate the significance of 15-PGDH/15-keto-PGE2 cascade in liver inflammation and tissue injury, we generated transgenic mice with targeted expression of 15-PGDH in the liver (15-PGDH Tg) and the animals were subjected to lipopolysaccharide (LPS)/Galactosamine (GalN)-induced acute liver inflammation and injury. Compared to the wild type mice, the 15-PGDH Tg mice showed lower levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), less liver tissue damage, less hepatic apoptosis/necrosis, less macrophage activation, and lower inflammatory cytokine production. In cultured Kupffer cells, treatment with 15-keto-PGE2 or the conditioned medium (CM) from 15-PGDH Tg hepatocyes inhibited LPS-induced cytokine production, in vitro. Both 15-keto-PGE2 and the CM from15-PGDH Tg hepatocyes also up-regulated the expression of PPAR-γ downstream genes in Kupffer cells. In cultured hepatocytes, 15-keto-PGE2 treatment or 15-PGDH overexpression did not influence TNF-α-induced hepatocyte apoptosis. These findings suggest that 15-PGDH protects against LPS/GalN-induced liver injury and the effect is mediated via 15-keto-PGE2, which activates PPAR-γ in Kupffer cells and thus inhibits their ability to produce inflammatory cytokines. Accordingly, we observed that the PPAR-γ antagonist, GW9662, reversed the effect of 15-keto-PGE2 in Kupffer cell in vitro and restored the susceptibility of 15-PGDH Tg mice to LPS/GalN-induced acute liver injury in vivo. Collectively, our findings suggest that 15-PGDH-derived 15-keto-PGE2 from hepatocytes is able to activate PPAR-γ and inhibit inflammatory cytokine production in Kupffer cells and that this paracrine mechanism negatively regulates LPS-induced necro-inflammatory response in the liver. Therefore, induction of 15-PGDH expression or utilization of 15-keto-PGE2 analogue may have therapeutic benefits for the treatment of endotoxin-associated liver inflammation/injury.
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Affiliation(s)
- Lu Yao
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, New Orleans, LA, United States of America
| | - Weina Chen
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, New Orleans, LA, United States of America
| | - Kyoungsub Song
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, New Orleans, LA, United States of America
| | - Chang Han
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, New Orleans, LA, United States of America
| | - Chandrashekhar R. Gandhi
- Department of Pediatrics, Cincinnati Children’s Hospital Medical Center and Department of Surgery, University of Cincinnati, Cincinnati, United States of America
| | - Kyu Lim
- Department of Biochemistry, College of Medicine, Cancer Research Institute and Infection Signaling Network Research Center, Chungnam National University, Daejeon, Korea
| | - Tong Wu
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, New Orleans, LA, United States of America
- * E-mail:
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Zhu C, Cao C, Wang X, Yuan J, Jin L, Li S. UCN enhances TGF-beta-mediated mitoinhibition of VSMCs via counteracting TGF-beta-induced cPLA2 expression and activation. Int J Biochem Cell Biol 2016; 80:98-108. [DOI: 10.1016/j.biocel.2016.09.028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Revised: 09/28/2016] [Accepted: 09/30/2016] [Indexed: 01/28/2023]
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17
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Nojima H, Kuboki S, Shinoda K, Shimizu H, Ohtsuka M, Kato A, Yoshitomi H, Furukawa K, Takayashiki T, Miyazaki M. Activation of peroxisome proliferator-activated receptor-gamma inhibits tumor growth by negatively regulating nuclear factor-κB activation in patients with hepatocellular carcinoma. JOURNAL OF HEPATO-BILIARY-PANCREATIC SCIENCES 2016; 23:574-84. [PMID: 27451128 DOI: 10.1002/jhbp.378] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Accepted: 07/15/2016] [Indexed: 12/13/2022]
Abstract
BACKGROUND The prognosis of advanced hepatocellular carcinoma (HCC) is poor because of its rapid progression. Peroxisome proliferator-activated receptor-gamma (PPARγ) is known to inhibit tumor growth in vitro; however, the behavior of PPARγ in clinical cases of HCC remains uncertain. METHODS Surgical specimens were collected from 104 HCC patients. The anti-neoplastic effects of PPARγ were evaluated. RESULTS PPARγ and its ligand expression were increased in some cases of HCC. When HCC patients were divided into two groups, tumor size was larger in patients with low PPARγ expression. Moreover, low PPARγ expression in HCC was an independent predictor of poorer prognosis. PPARγ expression was positively correlated with PPARγ activation and negatively correlated with NF-κB activation in HCC. PPARγ activation inhibited cell proliferation by inducing cell cycle arrest, through increased expression of p27(kip1) and decreased expression of cyclin D1 and interleukin-8. When HCC cells were treated with PPARγ ligands, PPARγ activation was increased and cell proliferation was inhibited in a dose-dependent manner. In contrast, PPARγ ligands negatively regulated NF-κB activation. CONCLUSIONS Activation of PPARγ induces cell cycle arrest and inhibits tumor progression by negatively regulating NF-κB activation in HCC. Therefore, PPARγ is an important endogenous regulator of HCC progression, and is a potential therapeutic target for HCC.
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Affiliation(s)
- Hiroyuki Nojima
- Department of General Surgery, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba, 260-0856, Japan
| | - Satoshi Kuboki
- Department of General Surgery, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba, 260-0856, Japan.
| | - Kimio Shinoda
- Department of General Surgery, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba, 260-0856, Japan
| | - Hiroaki Shimizu
- Department of General Surgery, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba, 260-0856, Japan
| | - Masayuki Ohtsuka
- Department of General Surgery, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba, 260-0856, Japan
| | - Atsushi Kato
- Department of General Surgery, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba, 260-0856, Japan
| | - Hideyuki Yoshitomi
- Department of General Surgery, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba, 260-0856, Japan
| | - Katsunori Furukawa
- Department of General Surgery, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba, 260-0856, Japan
| | - Tsukasa Takayashiki
- Department of General Surgery, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba, 260-0856, Japan
| | - Masaru Miyazaki
- Department of General Surgery, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba, 260-0856, Japan
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Yao L, Chen W, Han C, Wu T. Microsomal prostaglandin E synthase-1 protects against Fas-induced liver injury. Am J Physiol Gastrointest Liver Physiol 2016; 310:G1071-80. [PMID: 27102561 PMCID: PMC4935489 DOI: 10.1152/ajpgi.00327.2015] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Accepted: 04/17/2016] [Indexed: 01/31/2023]
Abstract
Microsomal prostaglandin E synthase-1 (mPGES-1) is the terminal enzyme for the synthesis of prostaglandin E2 (PGE2), a proproliferative and antiapoptotic lipid molecule important for tissue regeneration and injury repair. In this study, we developed transgenic (Tg) mice with targeted expression of mPGES-1 in the liver to assess Fas-induced hepatocyte apoptosis and acute liver injury. Compared with wild-type (WT) mice, the mPGES-1 Tg mice showed less liver hemorrhage, lower serum alanine transaminase (ALT) and aspartate transaminase (AST) levels, less hepatic necrosis/apoptosis, and lower level of caspase cascade activation after intraperitoneal injection of the anti-Fas antibody Jo2. Western blotting analysis revealed increased expression and activation of the serine/threonine kinase Akt and associated antiapoptotic molecules in the liver tissues of Jo2-treated mPGES-1 Tg mice. Pretreatment with the mPGES-1 inhibitor (MF63) or the Akt inhibitor (Akt inhibitor V) restored the susceptibility of the mPGES-1 Tg mice to Fas-induced liver injury. Our findings provide novel evidence that mPGES-1 prevents Fas-induced liver injury through activation of Akt and related signaling and suggest that induction of mPGES-1 or treatment with PGE2 may represent important therapeutic strategy for the prevention and treatment of Fas-associated liver injuries.
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Affiliation(s)
| | | | | | - Tong Wu
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, New Orleans, Louisiana
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19
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Kwon H, Song K, Han C, Chen W, Wang Y, Dash S, Lim K, Wu T. Inhibition of hedgehog signaling ameliorates hepatic inflammation in mice with nonalcoholic fatty liver disease. Hepatology 2016; 63:1155-69. [PMID: 26473743 PMCID: PMC4805465 DOI: 10.1002/hep.28289] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Accepted: 10/12/2015] [Indexed: 12/13/2022]
Abstract
UNLABELLED Hedgehog (Hh) signaling plays a critical role in liver development, regeneration, injury repair, and carcinogenesis. Activation of Hh signaling has been observed in patients with nonalcoholic fatty liver diseases (NAFLD); however, the pathobiological function and regulatory mechanism of hepatic Hh signaling in the pathogenesis of NAFLD remain to be further defined. This study was designed to examine the effect and mechanism of hepatic Hh signaling in high-fat diet-induced NAFLD by using pharmacological Smoothened (Smo) inhibitors (GDC-0449 and LED225) and liver-specific Smo knockout mice. Administration of Smo inhibitors to high-fat diet-fed wild-type mice significantly reduced the numbers of activated macrophages and decreased the expression of proinflammatory cytokines (tumor necrosis factor-α, interleukin-1β, monocyte chemoattractant protein 1, and interleukin-6) as assessed by F4/80 immunohistochemistry and quantitative reverse-transcription polymerase chain reaction, respectively. The Smo inhibitors were noted to have variable effects on hepatic fat accumulation. Liver-specific deletion of Smo also reduced macrophage activation and inhibited proinflammatory cytokine expression, while it did not significantly alter fat accumulation in the liver. Mechanistically, we found that activation of glioma-associated oncogene 1 by Hh signaling in primary hepatocytes increased the production of osteopontin, which subsequently enhanced the macrophage-mediated proinflammatory response through paracrine signaling. CONCLUSION Hepatocyte Hh signaling can promote liver inflammation through osteopontin-mediated macrophage activation; this mechanism importantly contributes to the progression of NAFLD.
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Affiliation(s)
- Hyunjoo Kwon
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, 1430 Tulane Avenue SL-79, New Orleans, Louisiana 70112
| | - Kyoungsub Song
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, 1430 Tulane Avenue SL-79, New Orleans, Louisiana 70112
| | - Chang Han
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, 1430 Tulane Avenue SL-79, New Orleans, Louisiana 70112
| | - Weina Chen
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, 1430 Tulane Avenue SL-79, New Orleans, Louisiana 70112
| | - Ying Wang
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, 1430 Tulane Avenue SL-79, New Orleans, Louisiana 70112,Department of Gastroenterology and Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China 430030
| | - Srikanta Dash
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, 1430 Tulane Avenue SL-79, New Orleans, Louisiana 70112
| | - Kyu Lim
- Department of Biochemistry, College of Medicine, Chungnam National University, Daejeon, Korea
| | - Tong Wu
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, 1430 Tulane Avenue SL-79, New Orleans, Louisiana 70112
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20
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Chen W, Han C, Zhang J, Song K, Wang Y, Wu T. Deletion of Mir155 prevents Fas-induced liver injury through up-regulation of Mcl-1. THE AMERICAN JOURNAL OF PATHOLOGY 2015; 185:1033-44. [PMID: 25794705 DOI: 10.1016/j.ajpath.2014.12.020] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Revised: 11/29/2014] [Accepted: 12/09/2014] [Indexed: 12/12/2022]
Abstract
Fas-induced apoptosis is involved in diverse liver diseases. Herein, we investigated the effect of Mir155 deletion on Fas-induced liver injury. Wild-type (WT) mice and Mir155 knockout (KO) mice were i.p. administered with the anti-Fas antibody (Jo2) to determine animal survival and the extent of liver injury. After Jo2 injection, the Mir155 KO mice exhibited prolonged survival versus the WT mice (P < 0.01). The Mir155 KO mice showed lower alanine aminotransferase and aspartate aminotransferase levels, less liver tissue damage, fewer apoptotic hepatocytes, and lower liver tissue caspase 3/7, 8, and 9 activities compared with the WT mice, indicating that Mir155 deletion prevents Fas-induced hepatocyte apoptosis and liver injury. Hepatocytes isolated from Mir155 KO mice also showed resistance to Fas-induced apoptosis, in vitro. Higher protein level of myeloid cell leukemia-1 (Mcl-1) was also observed in Mir155 KO hepatocytes compared to WT hepatocytes. A miR-155 binding site was identified in the 3'-untranslated region of Mcl-1 mRNA; Mcl1 was identified as a direct target of miR-155 in hepatocytes. Consistently, pretreatment with a siRNA specific for Mcl1 reversed Mir155 deletion-mediated protection against Jo2-induced liver tissue damage. Finally, restoration of Mir155 expression in Mir155 KO mice abolished the protection against Fas-induced hepatocyte apoptosis. Taken together, these findings demonstrate that deletion of Mir155 prevents Fas-induced hepatocyte apoptosis and liver injury through the up-regulation of Mcl1.
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Affiliation(s)
- Weina Chen
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, New Orleans, Louisiana
| | - Chang Han
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, New Orleans, Louisiana
| | - Jinqiang Zhang
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, New Orleans, Louisiana
| | - Kyoungsub Song
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, New Orleans, Louisiana
| | - Ying Wang
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, New Orleans, Louisiana; Department of Gastroenterology and Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Tong Wu
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, New Orleans, Louisiana.
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Chen W, Han C, Zhang J, Song K, Wang Y, Wu T. miR-150 Deficiency Protects against FAS-Induced Acute Liver Injury in Mice through Regulation of AKT. PLoS One 2015. [PMID: 26196694 PMCID: PMC4510058 DOI: 10.1371/journal.pone.0132734] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Although miR-150 is implicated in the regulation of immune cell differentiation and activation, it remains unknown whether miR-150 is involved in liver biology and disease. This study was performed to explore the potential role of miR-150 in LPS/D-GalN and Fas-induced liver injuries by using wild type and miR-150 knockout (KO) mice. Whereas knockout of miR-150 did not significantly alter LPS/D-GalN-induced animal death and liver injury, it protected against Fas-induced liver injury and mortality. The Jo2-induced increase in serum transaminases, apoptotic hepatocytes, PARP cleavage, as well as caspase-3/7, caspase-8, and caspase-9 activities were significantly attenuated in miR-150 KO mice. The liver tissues from Jo2-treated miR-150 KO mice expressed higher levels of Akt1, Akt2, total Akt, as well as p-Akt(Ser473) compared to the wild type livers. Pretreatment with the Akt inhibitor V reversed Jo2-induced liver injury in miR-150 KO mice. The primary hepatocytes isolated from miR-150 KO mice also showed protection against Fas-induced apoptosis in vitro (characterized by less prominent PARP cleavage, less nuclear fragmentation and less caspase activation) in comparison to hepatocytes from wild type mice. Luciferase reporter assays in hepatocytes transfected with the Akt1 or Akt2 3’-UTR reporter constructs (with or without mutation of miR-150 binding site) established Akt1 and Akt2 as direct targets of miR-150. Tail vein injection of lentiviral particles containing pre-miR-150 enhanced Jo2-induced liver injury in miR-150 KO mice. These findings demonstrate that miR-150 deficiency prevents Fas-induced hepatocyte apoptosis and liver injury through regulation of the Akt pathway.
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Affiliation(s)
- Weina Chen
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine,1430 Tulane Avenue SL-79, New Orleans, Louisiana, United States of America
| | - Chang Han
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine,1430 Tulane Avenue SL-79, New Orleans, Louisiana, United States of America
| | - Jinqiang Zhang
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine,1430 Tulane Avenue SL-79, New Orleans, Louisiana, United States of America
| | - Kyoungsub Song
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine,1430 Tulane Avenue SL-79, New Orleans, Louisiana, United States of America
| | - Ying Wang
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine,1430 Tulane Avenue SL-79, New Orleans, Louisiana, United States of America
- Department of Gastroenterology and Internal Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Tong Wu
- Department of Pathology and Laboratory Medicine, Tulane University School of Medicine,1430 Tulane Avenue SL-79, New Orleans, Louisiana, United States of America
- * E-mail:
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Lupo G, Motta C, Salmeri M, Spina-Purrello V, Alberghina M, Anfuso CD. An in vitro retinoblastoma human triple culture model of angiogenesis: a modulatory effect of TGF-β. Cancer Lett 2014; 354:181-8. [PMID: 25128651 DOI: 10.1016/j.canlet.2014.08.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Revised: 08/05/2014] [Accepted: 08/05/2014] [Indexed: 01/15/2023]
Abstract
Retinoblastoma is the most common intraocular tumour in children. In view of understanding the molecular mechanisms through which angiogenic switch on happens in the early phases of reciprocal interaction between tumour and cells constituting retinal microvessel, Transwell co-cultures constituted by human retinal endothelial cells (HREC), pericytes (HRPC), and human retinoblastoma cell line Y-79 were performed. Y-79 enhanced HREC proliferation, reduced by the introduction of HRPC in triple culture. In HREC/HRPC cultures, TGF-β in media increased, decreasing in triple cultures. High VEGF levels in triple cultures witnessed the establishment of a strongly in vitro angiogenic environment. Y-79 induced in HREC an increase in c- and iPLA2, phospho-cPLA2, inducible COX-2 protein expressions, PLA2 activities and prostaglandin E2 (PGE2) release. These effects were attenuated when HRPC were introduced in triple culture. Moreover, antibody silencing of TGF-β demonstrated a strong correlation between the signalling pathway triggered by TGF-β of pericytal origin and the phospholipase activation and the modulation of PGE2 release. Inhibiting VEGFA effect, the HRPC loss in triple culture decreased, showing its modulatory effect on their survival. Relying on the data here presented, sustaining the pericytal survival in a tumour retinal environment could ensure the integrity of microvessels and the TGF-β supply, essential for controlling aberrant endothelial pruning and angiogenesis.
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Affiliation(s)
- Gabriella Lupo
- Dipartimento di Biomedicina Clinica e Molecolare, Università di Catania, Italy
| | - Carla Motta
- Dipartimento di Biomedicina Clinica e Molecolare, Università di Catania, Italy
| | - Mario Salmeri
- Dipartimento di Scienze Bio-Mediche, Università di Catania, Italy
| | | | - Mario Alberghina
- Dipartimento di Biomedicina Clinica e Molecolare, Università di Catania, Italy
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Huang Q, Tan Y, Yin P, Ye G, Gao P, Lu X, Wang H, Xu G. Metabolic characterization of hepatocellular carcinoma using nontargeted tissue metabolomics. Cancer Res 2013; 73:4992-5002. [PMID: 23824744 DOI: 10.1158/0008-5472.can-13-0308] [Citation(s) in RCA: 308] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Hepatocellular carcinoma has a poor prognosis due to its rapid development and early metastasis. In this report, we characterized the metabolic features of hepatocellular carcinoma using a nontargeted metabolic profiling strategy based on liquid chromatography-mass spectrometry. Fifty pairs of liver cancer samples and matched normal tissues were collected from patients having hepatocellular carcinoma, including tumor tissues, adjacent noncancerous tissues, and distal noncancerous tissues, and 105 metabolites were filtered and identified from the tissue metabolome. The principal metabolic alternations in HCC tumors included elevated glycolysis, gluconeogenesis, and β-oxidation with reduced tricarboxylic acid cycle and Δ-12 desaturase. Furthermore, increased levels of glutathione and other antioxidative molecules, together with decreased levels of inflammatory-related polyunsaturated fatty acids and phospholipase A2, were observed. Differential metabolite levels in tissues were tested in 298 serum specimens from patients with chronic hepatitis, cirrhosis, and hepatocellular carcinoma. Betaine and propionylcarnitine were confirmed to confer good diagnostic potential to distinguish hepatocellular carcinoma from chronic hepatitis and cirrhosis. External validation of cirrhosis and hepatocellular carcinoma serum specimens further showed that this combination biomarker is useful for diagnosis of hepatocellular carcinoma with a supplementary role to α-fetoprotein.
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Affiliation(s)
- Qiang Huang
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, China
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PPARs and HCV-Related Hepatocarcinoma: A Mitochondrial Point of View. PPAR Res 2012; 2012:605302. [PMID: 22966221 PMCID: PMC3431172 DOI: 10.1155/2012/605302] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2012] [Accepted: 07/16/2012] [Indexed: 12/24/2022] Open
Abstract
Hepatitis-C-virus-related infective diseases are worldwide spread pathologies affecting primarily liver. The infection is often asymptomatic, but when chronically persisting can lead to liver scarring and ultimately to cirrhosis, which is generally apparent after decades. In some cases, cirrhosis will progress to develop liver failure, liver cancer, or life-threatening esophageal and gastric varices. HCV-infected cells undergo profound metabolic dysregulation whose mechanisms are yet not well understood. An emerging feature in the pathogenesis of the HCV-related disease is the setting of a pro-oxidative condition caused by dysfunctions of mitochondria which proved to be targets of viral proteins. This causes deregulation of mitochondria-dependent catabolic pathway including fatty acid oxidation. Nuclear receptors and their ligands are fundamental regulators of the liver metabolic homeostasis, which are disrupted following HCV infection. In this contest, specific attention has been focused on the peroxisome proliferator activated receptors given their role in controlling liver lipid metabolism and the availability of specific pharmacological drugs of potential therapeutic utilization. However, the reported role of PPARs in HCV infection provides conflicting results likely due to different species-specific contests. In this paper we summarize the current knowledge on this issue and offer a reconciling model based on mitochondria-related features.
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Cytosolic phospholipase A(2)α protects against Fas- but not LPS-induced liver injury. J Hepatol 2011; 55:1281-90. [PMID: 21703211 PMCID: PMC3221788 DOI: 10.1016/j.jhep.2011.03.017] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2010] [Revised: 02/27/2011] [Accepted: 03/01/2011] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS Cytosolic phospholipase A(2)α (cPLA(2)α) is a rate-limiting key enzyme controlling the release of arachidonic acid (AA) substrate for the synthesis of prostaglandins and leukotrienes. This study was designed to explore the role of hepatocyte cPLA(2)α in Fas-mediated liver injury, in vivo. METHODS Transgenic mice with targeted expression of cPLA(2)α under control of the albumin-promoter enhancer and wild-type mice were injected intraperitoneally with anti-Fas antibody Jo2 or lipopolysaccharide plus d-galactosamine and monitored for liver injury and survival at various time points. RESULTS The cPLA(2)α Tg mice resist Fas-induced liver failure, as reflected by the lower serum transaminase levels, fewer apoptotic hepatocytes, reduced caspase activation, and reduced PARP cleavage when compared to the matched wild type mice. Inhibition of cPLA(2)α by its pharmacological inhibitor, pyrrolidine, enhanced Jo2-induced liver injury in both cPLA(2)α Tg and wild type mice. Hepatic overexpression of cPLA(2)α increases the expression of EGFR in the liver and the EGFR inhibitor, AG1478, exacerbated Jo2-mediated liver injury. The cPLA(2)α transgenic mice develop more prominent liver tissue damage than wild-type mice after LPS/d-galactosamine injection. CONCLUSIONS Hepatocyte cPLA(2)α protects against Fas-induced liver injury and this effect is mediated at least in part through the upregulation of EGFR.
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Zhao L, Gandhi CR, Gao ZH. Involvement of cytosolic phospholipase A2 alpha signalling pathway in spontaneous and transforming growth factor-beta-induced activation of rat hepatic stellate cells. Liver Int 2011; 31:1565-73. [PMID: 22093332 DOI: 10.1111/j.1478-3231.2011.02632.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2010] [Accepted: 08/01/2011] [Indexed: 12/23/2022]
Abstract
BACKGROUND Hepatic stellate cells (HSCs) are extracellular matrix-producing cells that play a pivotal role in liver fibrogenesis. During liver injury and when cells are placed in vitro, HSCs undergo phenotypic transition from quiescent retinoid-storing cells to activated retinoid-deficient myofibroblast-like cells. Although several mediators including reactive oxygen species, platelet derived growth factor, transforming growth factor-beta (TGF-β) and tumour necrosis factor-alpha (TNF-α) were implicated in HSC activation, the cellular signalling pathways that regulate this process remain incompletely defined. AIMS The objectives of this study were to evaluate the role of cytosolic phospholipase A(2) alpha (cPLA(2)α) and peroxisome proliferator-activated receptor-beta/delta (PPAR-β/δ) in HSC activation. METHODS Rat HSCs were isolated, purified, cultured and stimulated with TGF-β1 in the presence or absence of the selective cPLA(2)α inhibitor, arachidonyltrifluoromethyl ketone (AACOCF(3)). The activation status of HSC was evaluated by immunofluorescent staining of alpha-smooth muscle actin (α-SMA) and by measuring the expression of cPLA(2)α, cyclooxygenase 2 (COX-2) and PPAR-β/δ using western blot analysis. RESULTS Rapid and significant increase in cPLA(2)α expression was observed during activation of HSCs. These events preceded the elevation of PPAR-β/δ and the expression of α-SMA. Elevated expression of cPLA(2)α, but not COX-2, was also observed during TGF-β-induced HSC activation. The TGF-β-induced α-SMA expression was blocked by AACOCF(3). Furthermore, transfection of a cPLA(2)α expression vector enhanced the transcription activity of PPAR-β/δ and the expression of α-SMA in HSCs. CONCLUSION cPLA(2)α-mediated induction of PPAR-β/δ is a novel intracellular signalling pathway in spontaneous and TGF-β induced activation of HSCs and could be a potential therapeutic target for the treatment of liver fibrosis.
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Affiliation(s)
- Liena Zhao
- Department of Pathology and Laboratory Medicine, University of Calgary and Calgary Laboratory Services, Calgary, AB, Canada
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Abstract
Chronic hepatitis B continues to be a major global health burden. It accounts for a substantial impact on health care resources and finances in many parts of the world including Europe. Natural history and disease spectrum are varied, depending on when and how the infection is acquired. The chronic infective state increases patients' risk of progression to liver cirrhosis or hepatocellular carcinoma. Several treatment options are currently available, but their use depends on the stage of the patient's infection, which is influenced by both host and viral factors. The ultimate goals in hepatitis B treatment are to prevent disease progression, hepatic decompensation, hepatocellular carcinoma, and death. Patients with decompensated liver cirrhosis should be referred to specialized transplant centers in a timely manner.
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Abstract
The goal of hepatitis B treatment is to prevent cirrhosis, liver decompensation and hepatocellular carcinoma. In clinical practice, treatment response is determined by suppression of serum HBV DNA levels, hepatitis B e antigen seroconversion to hepatitis B e antibody, hepatitis B surface antigen loss, normalization of alanine aminotransferase levels and improvement in liver histology. Patients with life-threatening liver disease, and those with high levels of HBV replication and active or advanced liver disease, should be treated. Other patients should be monitored so that treatment can be initiated when indicated. Currently, seven medications are approved for the treatment of hepatitis B: two formulations of interferon and five nucleos(t)ide analogues. Interferon is administered for a finite duration while nucleos(t)ide analogues are usually administered for many years. Antiviral drug resistance is a major limiting factor to the success of nucleos(t)ide analogue treatment; therefore, treatment should be initiated with drugs that have a high genetic barrier to resistance (that is, a low potential for drug resistance). In addition, treatment response should be closely monitored to detect virologic breakthroughs, and the importance of medication adherence should be emphasized. Management of patients with treatment failure should be tailored according to the type of treatment failure (lack of initial response versus virologic breakthrough), the treatment that the patient is receiving, history of prior treatment, and the pretreatment characteristics of both the patient and the disease.
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Abstract
Infection with hepatitis viruses can lead to acute hepatitis with the risk of developing liver failure. Chronic viral hepatitis may evolve into liver cirrhosis and hepatocellular carcinoma. Thus, prevention of viral hepatitis and its sequels is essential. Vaccination against hepatitis A is successful in almost all individuals. Protective antibodies maintain for at least 20 years. Booster vaccinations are not necessary. Since the introduction of hepatitis A vaccines, the incidence of new HAV-infections has declined significantly. Hepatitis B vaccines are safe and highly effective. Special populations such as dialysis patients or immunocompromised patients require special vaccine schedules. New vaccines with improved adjuvants are currently being tested in clinical trials. So far there is no hepatitis C vaccine on the horizon. Prophylaxis of HCV-infections relies primarily on hygiene measures. Early therapy of acute hepatitis C can prevent chronic hepatitis C. HDV-infection can only be established if HBsAg is present. Thus, prevention of hepatitis B or elimination of HBsAg means prevention of hepatitis delta. Hepatitis E vaccines have been evaluated in phase III studies. The development of HEV vaccines becomes more relevant since chronic HEV infections have been reported in immunosuppressed individuals.
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Affiliation(s)
- M Cornberg
- Klinik für Gastroenterologie, Hepatologie und Endokrinologie, Medizinische Hochschule Hannover, Carl-Neuberg-Strasse 1, Hannover, Germany.
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