1
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Xu S, Yang X, Chen Q, Liu Z, Chen Y, Yao X, Xiao A, Tian J, Xie L, Zhou M, Hu Z, Zhu F, Xu X, Hou F, Nie J. Leukemia inhibitory factor is a therapeutic target for renal interstitial fibrosis. EBioMedicine 2022; 86:104312. [PMID: 36335669 PMCID: PMC9646860 DOI: 10.1016/j.ebiom.2022.104312] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Revised: 09/28/2022] [Accepted: 10/04/2022] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND The role of the IL6 family members in organ fibrosis, including renal interstitial fibrosis (TIF), has been widely explored. However, few studies have ever simultaneously examined them in the same cohort of patients. Besides, the role of leukemia inhibitory factor (LIF) in TIF remains unclear. METHODS RNA-seq data of kidney biopsies from chronic kidney disease (CKD) patients, in both public databases and our assays, were used to analyze transcript levels of IL6 family members. Two TIF mouse models, the unilateral ureteral obstruction (UUO) and the ischemia reperfusion injury (IRI), were employed to validate the finding. To assess the role of LIF in vivo, short hairpin RNA, lenti-GFP-LIF was used to knockdown LIF receptor (LIFR), overexpress LIF, respectively. LIF-neutralizing antibody was used in therapeutic studies. Whether urinary LIF could be used as a promising predictor for CKD progression was investigated in a prospective observation patient cohort. FINDINGS Among IL6 family members, LIF is the most upregulated one in both human and mouse renal fibrotic lesions. The mRNA level of LIF negatively correlated with eGFR with the strongest correlation and the smallest P value. Baseline urinary concentrations of LIF in CKD patients predict the risk of CKD progression to end-stage kidney disease by Kaplan-Meier analysis. In mouse TIF models, knockdown of LIFR alleviated TIF; conversely, overexpressing LIF exacerbated TIF. Most encouragingly, visible efficacy against TIF was observed by administering LIF-neutralizing antibodies to mice. Mechanistically, LIF-LIFR-EGR1 axis and Sonic Hedgehog signaling formed a vicious cycle between fibroblasts and proximal tubular cells to augment LIF expression and promote the pro-fibrotic response via ERK and STAT3 activation. INTERPRETATION This study discovered that LIF is a noninvasive biomarker for the progression of CKD and a potential therapeutic target of TIF. FUNDINGS Stated in the Acknowledgements section of the manuscript.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | - Fanfan Hou
- Corresponding author. Division of Nephrology, Nanfang Hospital, Southern Medical University, Guangzhou, China.
| | - Jing Nie
- Corresponding author. Division of Nephrology, Nanfang Hospital, Southern Medical University, Guangzhou, China.
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2
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Christianson J, Oxford JT, Jorcyk CL. Emerging Perspectives on Leukemia Inhibitory Factor and its Receptor in Cancer. Front Oncol 2021; 11:693724. [PMID: 34395259 PMCID: PMC8358831 DOI: 10.3389/fonc.2021.693724] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Accepted: 07/13/2021] [Indexed: 12/26/2022] Open
Abstract
Tumorigenesis and metastasis have deep connections to inflammation and inflammatory cytokines, but the mechanisms underlying these relationships are poorly understood. Leukemia Inhibitory Factor (LIF) and its receptor (LIFR), part of the interleukin-6 (IL-6) cytokine family, make up one such ill-defined piece of the puzzle connecting inflammation to cancer. Although other members of the IL-6 family have been shown to be involved in the metastasis of multiple types of cancer, the role of LIF and LIFR has been challenging to determine. Described by others in the past as enigmatic and paradoxical, LIF and LIFR are expressed in a diverse array of cells in the body, and the narrative surrounding them in cancer-related processes has been vague, and at times even contradictory. Despite this, recent insights into their functional roles in cancer have highlighted interesting patterns that may allude to a broader understanding of LIF and LIFR within tumor growth and metastasis. This review will discuss in depth the signaling pathways activated by LIF and LIFR specifically in the context of cancer-the purpose being to summarize recent literature concerning the downstream effects of LIF/LIFR signaling in a variety of cancer-related circumstances in an effort to begin teasing out the intricate web of contradictions that have made this pair so challenging to define.
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Affiliation(s)
- Joe Christianson
- Department of Biological Sciences, Boise State University, Boise, ID, United States
- Biomolecular Sciences Program, Boise State University, Boise, ID, United States
| | - Julia Thom Oxford
- Department of Biological Sciences, Boise State University, Boise, ID, United States
- Biomolecular Sciences Program, Boise State University, Boise, ID, United States
| | - Cheryl L. Jorcyk
- Department of Biological Sciences, Boise State University, Boise, ID, United States
- Biomolecular Sciences Program, Boise State University, Boise, ID, United States
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3
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Welc SS, Flores I, Wehling-Henricks M, Ramos J, Wang Y, Bertoni C, Tidball JG. Targeting a therapeutic LIF transgene to muscle via the immune system ameliorates muscular dystrophy. Nat Commun 2019; 10:2788. [PMID: 31243277 PMCID: PMC6594976 DOI: 10.1038/s41467-019-10614-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Accepted: 05/22/2019] [Indexed: 12/18/2022] Open
Abstract
Many potentially therapeutic molecules have been identified for treating Duchenne muscular dystrophy. However, targeting those molecules only to sites of active pathology is an obstacle to their clinical use. Because dystrophic muscles become extensively inflamed, we tested whether expressing a therapeutic transgene in leukocyte progenitors that invade muscle would provide selective, timely delivery to diseased muscle. We designed a transgene in which leukemia inhibitory factor (LIF) is under control of a leukocyte-specific promoter and transplanted transgenic cells into dystrophic mice. Transplantation diminishes pathology, reduces Th2 cytokines in muscle and biases macrophages away from a CD163+/CD206+ phenotype that promotes fibrosis. Transgenic cells also abrogate TGFβ signaling, reduce fibro/adipogenic progenitor cells and reduce fibrogenesis of muscle cells. These findings indicate that leukocytes expressing a LIF transgene reduce fibrosis by suppressing type 2 immunity and highlight a novel application by which immune cells can be genetically modified as potential therapeutics to treat muscle disease.
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Affiliation(s)
- Steven S Welc
- Department of Integrative Biology and Physiology, University of California, Los Angeles, CA, 90095-1606, USA
| | - Ivan Flores
- Molecular, Cellular & Integrative Physiology Program, University of California, Los Angeles, CA, 90095-1606, USA
| | - Michelle Wehling-Henricks
- Department of Integrative Biology and Physiology, University of California, Los Angeles, CA, 90095-1606, USA
| | - Julian Ramos
- Department of Integrative Biology and Physiology, University of California, Los Angeles, CA, 90095-1606, USA
| | - Ying Wang
- Molecular, Cellular & Integrative Physiology Program, University of California, Los Angeles, CA, 90095-1606, USA
| | - Carmen Bertoni
- Department of Neurology, David Geffen School of Medicine at UCLA, University of California, Los Angeles, CA, 90095, USA
| | - James G Tidball
- Department of Integrative Biology and Physiology, University of California, Los Angeles, CA, 90095-1606, USA.
- Molecular, Cellular & Integrative Physiology Program, University of California, Los Angeles, CA, 90095-1606, USA.
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine at UCLA, University of California, Los Angeles, CA, 90095, USA.
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4
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Butturini E, Cozzolino F, Boriero D, Carcereri de Prati A, Monti M, Rossin M, Canetti D, Cellini B, Pucci P, Mariotto S. S-glutathionylation exerts opposing roles in the regulation of STAT1 and STAT3 signaling in reactive microglia. Free Radic Biol Med 2018; 117:191-201. [PMID: 29427792 DOI: 10.1016/j.freeradbiomed.2018.02.005] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Revised: 02/02/2018] [Accepted: 02/03/2018] [Indexed: 10/18/2022]
Abstract
STAT1 and STAT3 are two transcription factors involved in a lot of cellular functions such as immune response, proliferation, apoptosis, and cell survival. A number of literature evidences described a yin-yang relationship between activation of STAT1 and STAT3 in neurodegenerative disorders where STAT1 exerts a pro-apoptotic effect whereas STAT3 shows neuroprotective properties through the inhibition of apoptosis. Although the role of oxidative-stress in the pathogenesis of neurodegeneration is clearly described, its influence in the regulation of these pathways is poorly understood. Herein, we demonstrate that H2O2 rapidly induces phosphorylation of STAT1 whereas it is not able to influence phosphorylation of STAT3 in mouse microglia BV2 cells. The analysis of the molecular mechanism of STATs signaling reveals that H2O2 induces S-glutathionylation of both STAT1 and STAT3. The same post-translational event exerts an opposing role in the regulation of STAT1 and STAT3 signaling. These data not only confirm redox sensibility of STAT3 signaling but also reveal for the first time that STAT1 is susceptible to redox regulation. A deep study of the molecular mechanism of STAT1 redox regulation, identifies Cys324 and Cys492 as the main targets of S-glutathionylation and confirms that S-glutathionylation does not impair JAK2 mediated STAT1 tyrosine phosphorylation. These results demonstrate that both phosphorylation and glutathionylation contribute to activation of STAT1 during oxidative stress and underline that the same post-translation event exerts an opposing role in the regulation of STAT1 and STAT3 signaling in microglia cells.
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Affiliation(s)
- Elena Butturini
- Department of Neuroscience, Biomedicine and Movement Sciences, Section of Biological Chemistry, University of Verona, Strada Le Grazie, 8, 37134 Verona, Italy
| | - Flora Cozzolino
- CEINGE Biotecnologie Avanzate and Department of Chemical Science, University of Naples "Federico II, Naples, Italy
| | - Diana Boriero
- Department of Neuroscience, Biomedicine and Movement Sciences, Section of Biological Chemistry, University of Verona, Strada Le Grazie, 8, 37134 Verona, Italy
| | - Alessandra Carcereri de Prati
- Department of Neuroscience, Biomedicine and Movement Sciences, Section of Biological Chemistry, University of Verona, Strada Le Grazie, 8, 37134 Verona, Italy
| | - Maria Monti
- CEINGE Biotecnologie Avanzate and Department of Chemical Science, University of Naples "Federico II, Naples, Italy
| | - Michele Rossin
- Department of Neuroscience, Biomedicine and Movement Sciences, Section of Biological Chemistry, University of Verona, Strada Le Grazie, 8, 37134 Verona, Italy; CEINGE Biotecnologie Avanzate and Department of Chemical Science, University of Naples "Federico II, Naples, Italy; Department of Experimental Medicine, University of Perugia, Perugia, Italy3
| | - Diana Canetti
- CEINGE Biotecnologie Avanzate and Department of Chemical Science, University of Naples "Federico II, Naples, Italy
| | - Barbara Cellini
- Department of Experimental Medicine, University of Perugia, Perugia, Italy3
| | - Piero Pucci
- CEINGE Biotecnologie Avanzate and Department of Chemical Science, University of Naples "Federico II, Naples, Italy
| | - Sofia Mariotto
- Department of Neuroscience, Biomedicine and Movement Sciences, Section of Biological Chemistry, University of Verona, Strada Le Grazie, 8, 37134 Verona, Italy.
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5
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Xu L, Long J, Shi C, Zhang N, Lv Y, Feng J, Xuan A, He X, Li Q, Bai Y, Liu S, Long D. Effect of leukocyte inhibitory factor on neuron differentiation from human induced pluripotent stem cell-derived neural precursor cells. Int J Mol Med 2018; 41:2037-2049. [PMID: 29393372 PMCID: PMC5810244 DOI: 10.3892/ijmm.2018.3418] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 01/05/2018] [Indexed: 12/27/2022] Open
Abstract
Direct derivation of human induced pluripotent stem cells into neural precursor cells and differentiation of these into neurons holds great promise in the cell therapy of neuro-degenerative diseases. However, the availability and survival rate of neurons requires improvement. In the present study, it was found that the addition of 5 ng/ml leukocyte inhibitory factor (LIF) during the process of differentiation significantly improved the expression of neuron-specific class III β-tubulin (TUJ1) and microtubule-associated protein 2 (MAP2), as detected by immunofluorescence and western blotting. In addition, LIF improved the cell viability, increased the expression of phosphorylated-protein kinase B (AKT), downregulated the expression of proinflammatory cytokines, including interleukin-1α (IL-1α) and tumor necrosis factor-α (TNF-α), and upregulated the expression of anti-inflammatory cytokines, including interleukin-10 (IL-10) and transforming growth factor-β (TGF-β). After adding the phosphatidylinositol 3-kinase (PI3K)/AKT signaling inhibitor LY294002 or wortmannin to the LIF differentiation group, LIF-induced changes in the protein expression of TUJ1 and MAP2 were reversed, but this effect could not be prevented by rapamycin, a mechanistic target of rapamycin signaling inhibitor. The expression of cytokines associated with inflammation and cell viability was reversed by LY294002 and wortmannin, but not by rapamycin. In conclusion, LIF could improve neuronal differentiation and survival through the activation of PI3K/AKT signaling and the anti-inflammatory effect. The anti-inflammatory effect may be mediated by the activation of PI3K/AKT.
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Affiliation(s)
- Liping Xu
- Key Laboratory of Neuroscience, School of Basic Medical Sciences, Guangzhou Medical University, Guangzhou, Guangdong 511436, P.R. China
| | - Jingyi Long
- Institute of Neuroscience and The Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, Guangdong 511436, P.R. China
| | - Chun Shi
- Key Laboratory of Neuroscience, School of Basic Medical Sciences, Guangzhou Medical University, Guangzhou, Guangdong 511436, P.R. China
| | - Nianping Zhang
- Key Laboratory of Neuroscience, School of Basic Medical Sciences, Guangzhou Medical University, Guangzhou, Guangdong 511436, P.R. China
| | - Ying Lv
- Key Laboratory of Neuroscience, School of Basic Medical Sciences, Guangzhou Medical University, Guangzhou, Guangdong 511436, P.R. China
| | - Junda Feng
- Key Laboratory of Neuroscience, School of Basic Medical Sciences, Guangzhou Medical University, Guangzhou, Guangdong 511436, P.R. China
| | - Aiguo Xuan
- Key Laboratory of Neuroscience, School of Basic Medical Sciences, Guangzhou Medical University, Guangzhou, Guangdong 511436, P.R. China
| | - Xiaosong He
- Key Laboratory of Neuroscience, School of Basic Medical Sciences, Guangzhou Medical University, Guangzhou, Guangdong 511436, P.R. China
| | - Qingqing Li
- Key Laboratory of Neuroscience, School of Basic Medical Sciences, Guangzhou Medical University, Guangzhou, Guangdong 511436, P.R. China
| | - Yinshan Bai
- Key Laboratory of Neuroscience, School of Basic Medical Sciences, Guangzhou Medical University, Guangzhou, Guangdong 511436, P.R. China
| | - Shanshan Liu
- Key Laboratory of Neuroscience, School of Basic Medical Sciences, Guangzhou Medical University, Guangzhou, Guangdong 511436, P.R. China
| | - Dahong Long
- Key Laboratory of Neuroscience, School of Basic Medical Sciences, Guangzhou Medical University, Guangzhou, Guangdong 511436, P.R. China
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6
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Engelhardt M, Hamad MIK, Jack A, Ahmed K, König J, Rennau LM, Jamann N, Räk A, Schönfelder S, Riedel C, Wirth MJ, Patz S, Wahle P. Interneuron synaptopathy in developing rat cortex induced by the pro-inflammatory cytokine LIF. Exp Neurol 2018; 302:169-180. [PMID: 29305051 DOI: 10.1016/j.expneurol.2017.12.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 12/08/2017] [Accepted: 12/26/2017] [Indexed: 12/31/2022]
Affiliation(s)
- Maren Engelhardt
- Developmental Neurobiology, Faculty of Biology and Biotechnology, Ruhr University Bochum, Germany; Institute of Neuroanatomy, Medical Faculty Mannheim, CBTM, Heidelberg University, Germany
| | - Mohammad I K Hamad
- Developmental Neurobiology, Faculty of Biology and Biotechnology, Ruhr University Bochum, Germany
| | - Alexander Jack
- Developmental Neurobiology, Faculty of Biology and Biotechnology, Ruhr University Bochum, Germany
| | - Küpra Ahmed
- Developmental Neurobiology, Faculty of Biology and Biotechnology, Ruhr University Bochum, Germany
| | - Jennifer König
- Developmental Neurobiology, Faculty of Biology and Biotechnology, Ruhr University Bochum, Germany
| | - Lisa Marie Rennau
- Developmental Neurobiology, Faculty of Biology and Biotechnology, Ruhr University Bochum, Germany
| | - Nora Jamann
- Institute of Neuroanatomy, Medical Faculty Mannheim, CBTM, Heidelberg University, Germany
| | - Andrea Räk
- Developmental Neurobiology, Faculty of Biology and Biotechnology, Ruhr University Bochum, Germany
| | - Sabine Schönfelder
- Developmental Neurobiology, Faculty of Biology and Biotechnology, Ruhr University Bochum, Germany
| | - Christian Riedel
- Developmental Neurobiology, Faculty of Biology and Biotechnology, Ruhr University Bochum, Germany
| | - Markus Joseph Wirth
- Developmental Neurobiology, Faculty of Biology and Biotechnology, Ruhr University Bochum, Germany; Institute of Biology-II, RWTH Aachen University, Aachen, Germany
| | - Silke Patz
- Developmental Neurobiology, Faculty of Biology and Biotechnology, Ruhr University Bochum, Germany; Research Unit for Experimental Neurotraumatology, Department of Neurosurgery, Medical University of Graz, Graz, Austria
| | - Petra Wahle
- Developmental Neurobiology, Faculty of Biology and Biotechnology, Ruhr University Bochum, Germany.
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7
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Guo H, Cheng Y, Martinka M, McElwee K. High LIFr expression stimulates melanoma cell migration and is associated with unfavorable prognosis in melanoma. Oncotarget 2016; 6:25484-98. [PMID: 26329521 PMCID: PMC4694846 DOI: 10.18632/oncotarget.4688] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Accepted: 07/13/2015] [Indexed: 11/25/2022] Open
Abstract
Increased or decreased expression of LIF receptor (LIFr) has been reported in several human cancers, including skin cancer, but its role in melanoma is unknown. In this study, we investigated the expression pattern of LIFr in melanoma and assessed its prognostic value. Using tissue microarrays consisting of 441 melanomas and 96 nevi, we found that no normal nevi showed high LIFr expression. LIFr staining was significantly increased in primary melanoma compared to dysplastic nevi (P = 0.0003) and further increased in metastatic melanoma (P = 0.0000). Kaplan–Meier survival curve and univariate Cox regression analyses showed that increased expression of LIFr was correlated with poorer 5-year patient survival (overall survival, P = 0.0000; disease-specific survival, P = 0.0000). Multivariate Cox regression analyses indicated that increased LIFr expression was an independent prognostic marker for primary melanoma (P = 0.036). LIFr knockdown inhibited melanoma cell migration in wound healing assays and reduced stress fiber formation. LIFr knockdown correlated with STAT3 suppression, but not YAP, suggesting that LIFr activation might stimulate melanoma cell migration through the STAT3 pathway. Our data indicate that strong LIFr expression identifies potentially highly malignant melanocytic lesions at an early stage and LIFr may be a potential target for the development of early intervention therapeutics.
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Affiliation(s)
- Hongwei Guo
- Department of Dermatology and Skin Science, University of British Columbia, Vancouver, Canada.,Department of Dermatology, Affiliated Hospital of Guangdong Medical College, Zhanjiang, Guangdong, China
| | - Yabin Cheng
- Department of Dermatology and Skin Science, University of British Columbia, Vancouver, Canada
| | - Magdalena Martinka
- Department of Pathology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Kevin McElwee
- Department of Dermatology and Skin Science, University of British Columbia, Vancouver, Canada
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8
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Kalyanasundaram Bhanumathy K, Zhang B, Xie Y, Xu A, Tan X, Xiang J. Potent immunotherapy against well-established thymoma using adoptively transferred transgeneIL-6-engineered dendritic cell-stimulated CD8+T-cells with prolonged survival and enhanced cytotoxicity. J Gene Med 2015. [DOI: 10.1002/jgm.2836] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Affiliation(s)
| | - Bei Zhang
- Cancer Research Cluster, Saskatchewan Cancer Agency, Division of Oncology; University of Saskatchewan; Saskatoon Saskatchewan Canada
| | - Yufeng Xie
- Cancer Research Cluster, Saskatchewan Cancer Agency, Division of Oncology; University of Saskatchewan; Saskatoon Saskatchewan Canada
| | - Aizhang Xu
- Cancer Research Cluster, Saskatchewan Cancer Agency, Division of Oncology; University of Saskatchewan; Saskatoon Saskatchewan Canada
| | - Xin Tan
- College of Life Science; Beijing Institute of Technology; Beijing China
| | - Jim Xiang
- Cancer Research Cluster, Saskatchewan Cancer Agency, Division of Oncology; University of Saskatchewan; Saskatoon Saskatchewan Canada
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9
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Liang XH, Deng WB, Li M, Zhao ZA, Wang TS, Feng XH, Cao YJ, Duan EK, Yang ZM. Egr1 protein acts downstream of estrogen-leukemia inhibitory factor (LIF)-STAT3 pathway and plays a role during implantation through targeting Wnt4. J Biol Chem 2014; 289:23534-45. [PMID: 25012664 DOI: 10.1074/jbc.m114.588897] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Embryo implantation is a highly synchronized process between an activated blastocyst and a receptive uterus. Successful implantation relies on the dynamic interplay of estrogen and progesterone, but the key mediators underlying embryo implantation are not fully understood. Here we show that transcription factor early growth response 1 (Egr1) is regulated by estrogen as a downstream target through leukemia inhibitory factor (LIF) signal transducer and activator of transcription 3 (STAT3) pathway in mouse uterus. Egr1 is localized in the subluminal stromal cells surrounding the implanting embryo on day 5 of pregnancy. Estrogen rapidly, markedly, and transiently enhances Egr1 expression in uterine stromal cells, which fails in estrogen receptor α knock-out mouse uteri. STAT3 is phosphorylated by LIF and subsequently recruited on Egr1 promoter to induce its expression. Our results of Egr1 expression under induced decidualization in vivo and in vitro show that Egr1 is rapidly induced after deciduogenic stimulus. Egr1 knockdown can inhibit in vitro decidualization of cultured uterine stromal cells. Chromatin immunoprecipitation data show that Egr1 is recruited to the promoter of wingless-related murine mammary tumor virus integration site 4 (Wnt4). Collectively, our study presents for the first time that estrogen regulates Egr1 expression through LIF-STAT3 signaling pathway in mouse uterus, and Egr1 functions as a critical mediator of stromal cell decidualization by regulating Wnt4.
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Affiliation(s)
- Xiao-Huan Liang
- From the College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Wen-Bo Deng
- From the College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China
| | - Ming Li
- College of Life Science, Xiamen University, Xiamen 361005, China
| | - Zhen-Ao Zhao
- State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Science, Beijing 100101, China, and
| | - Tong-Song Wang
- Department of Biology, Shantou University, Shantou 515063, China
| | - Xu-Hui Feng
- College of Life Science, Xiamen University, Xiamen 361005, China
| | - Yu-Jing Cao
- State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Science, Beijing 100101, China, and
| | - En-Kui Duan
- State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Science, Beijing 100101, China, and
| | - Zeng-Ming Yang
- From the College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, China,
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10
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Hall VJ, Hyttel P. Breaking down pluripotency in the porcine embryo reveals both a premature and reticent stem cell state in the inner cell mass and unique expression profiles of the naive and primed stem cell states. Stem Cells Dev 2014; 23:2030-45. [PMID: 24742229 DOI: 10.1089/scd.2013.0502] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
To date, it has been difficult to establish bona fide porcine embryonic stem cells (pESC) and stable induced pluripotent stem cells. Reasons for this remain unclear, but they may depend on inappropriate culture conditions. This study reports the most insights to date on genes expressed in the pluripotent cells of the porcine embryo, namely the inner cell mass (ICM), the trophectoderm-covered epiblast (EPI), and the embryonic disc epiblast (ED). Specifically, we reveal that the early porcine ICM represents a premature state of pluripotency due to lack of translation of key pluripotent proteins, and the late ICM enters a transient, reticent pluripotent state which lacks expression of most genes associated with pluripotency. We describe a unique expression profile of the porcine EPI, reflecting the naive stem cell state, including expression of OCT4, NANOG, CRIPTO, and SSEA-1; weak expression of NrOB1 and REX1; but very limited expression of genes in classical pathways involved in regulating pluripotency. The porcine ED, reflecting the primed stem cell state, can be characterized by the expression of OCT4, NANOG, SOX2, KLF4, cMYC, REX1, CRIPTO, and KLF2. Further cell culture experiments using inhibitors against FGF, JAK/STAT, BMP, WNT, and NODAL pathways on cell cultures derived from day 5 and 10 embryos reveal the importance of FGF, JAK/STAT, and BMP signaling in maintaining cell proliferation of pESCs in vitro. Together, this article provides new insights into the regulation of pluripotency, revealing unique stem cell states in the different porcine stem cell populations derived from the early developing embryo.
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Affiliation(s)
- Vanessa Jane Hall
- Department of Veterinary Clinical and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen , Frederiksberg C, Denmark
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11
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Wu J, Akkuratov EE, Bai Y, Gaskill CM, Askari A, Liu L. Cell signaling associated with Na(+)/K(+)-ATPase: activation of phosphatidylinositide 3-kinase IA/Akt by ouabain is independent of Src. Biochemistry 2013; 52:9059-67. [PMID: 24266852 PMCID: PMC3868411 DOI: 10.1021/bi4011804] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
Exposure
of intact cells to selective inhibitors of Na+/K+-ATPase such as ouabain activates several growth-related
cell signaling pathways. It has been suggested that the initial event
of these pathways is the binding of ouabain to a preexisting complex
of Src with Na+/K+-ATPase of the plasma membrane.
The aim of this work was to evaluate the role of Src in the ouabain-induced
activation of phosphatidylinositide 3-kinase 1A (PI3K1A) and its downstream
consequences. When fibroblasts devoid of Src (SYF cells) and controls
(Src++ cells) were exposed to ouabain, PI3K1A, Akt, and
proliferative growth were similarly stimulated in both cell lines.
Ouabain-induced activation of Akt was not prevented by the Src inhibitor
PP2. In contrast, ERK1/2 were not activated by ouabain in SYF cells
but were stimulated in Src++ cells; this was prevented
by PP2. In isolated adult mouse cardiac myocytes, where ouabain induces
hypertrophic growth, PP2 also did not prevent ouabain-induced activation
of Akt and the resulting hypertrophy. Ouabain-induced increases in
the levels of co-immunoprecipitation of the α-subunit of Na+/K+-ATPase with the p85 subunit of PI3K1A were
noted in SYF cells, Src++ cells, and adult cardiac myocytes.
In conjunction with previous findings, the results presented here
indicate that (a) if there is a preformed complex of Src and Na+/K+-ATPase, it is irrelevant to ouabain-induced
activation of the PI3K1A/Akt pathway through Na+/K+-ATPase and (b) a more likely, but not established, mechanism
of linkage of Na+/K+-ATPase to PI3K1A is the
ouabain-induced interaction of a proline-rich domain of the α-subunit
of Na+/K+-ATPase with the SH3 domain of the
p85 subunit of PI3K1A.
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Affiliation(s)
- Jian Wu
- Department of Biochemistry and Cancer Biology, College of Medicine and Life Sciences, University of Toledo Health Science Campus , Toledo, Ohio 43614, United States
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Piazza TM, Lu JC, Carver KC, Schuler LA. SRC family kinases accelerate prolactin receptor internalization, modulating trafficking and signaling in breast cancer cells. Mol Endocrinol 2008; 23:202-12. [PMID: 19056863 DOI: 10.1210/me.2008-0341] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Despite the growing body of evidence supporting prolactin (PRL) actions in human breast cancer, little is known regarding PRL regulation of its own receptor in these cells. Ligand-initiated endocytosis is a key process in the regulation of receptor availability and signaling cascades that may lead to oncogenic actions. Although exposure to exogenous PRL accelerates degradation of the long isoform of the PRL receptor (lPRLR), neither the signals initiated by PRL that lead to lPRLR internalization and subsequent down-regulation, nor the relationship to downstream pathways are understood in breast cancer cells. In this study, we showed that PRL-induced down-regulation of the lPRLR was reduced by inhibition of src family kinases (SFKs), but not Janus kinase 2, in MCF-7 cells. Inhibition of SFKs also resulted in accumulation of a PRL-induced PRLR fragment containing the extracellular domain, which appeared to be generated from newly synthesized PRLR. lPRLR was constitutively associated with SFKs in lipid rafts. PRL-induced SFK activation led to recruitment of the guanosine triphosphatase, dynamin-2, to an internalization complex, resulting in endocytosis. Inhibition of endocytosis by small interfering RNA-mediated knockdown of dynamin-2 blocked PRL-induced down-regulation of lPRLR, confirming that internalization is essential for this process. Endocytosis also was required for optimal phosphorylation of ERK1/2 and Akt, but not for Janus kinase 2 or signal transducer and activator of transcription 5, indicating that internalization selectively modulates signaling cascades. Together, these data indicate that SFKs are key mediators of ligand-initiated lPRLR internalization, down-regulation, and signal transduction in breast cancer cells, and underscore the importance of target cell context in receptor trafficking and signal transduction.
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Affiliation(s)
- Timothy M Piazza
- Department of Comparative Biosciences, University of Wisconsin, Madison, Wisconsin 53706, USA
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13
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O'Brien JJ, Nathanson NM. Retrograde activation of STAT3 by leukemia inhibitory factor in sympathetic neurons. J Neurochem 2007; 103:288-302. [PMID: 17608645 DOI: 10.1111/j.1471-4159.2007.04736.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Leukemia inhibitory factor (LIF) is a member of the interleukin-6 family of cytokines and signals through the glycoprotein 130 and LIF receptor beta subunits. Binding of cytokines to these subunits activates multiple signaling cascades, including the Janus kinase (Jak)/signal transducers and activators of transcription (STAT) pathway. We used compartmentalized cultures of sympathetic neurons and immunocytochemical analyses of STAT3 to examine the mechanisms involved in retrograde signaling of LIF from distal neurites (DN) to cell bodies. Addition of LIF to the DN of these neurons triggers the activation and nuclear translocation of STAT3. Inhibition of Jak activity in the cell bodies prevented LIF-induced retrograde activation of STAT3, while block of Jak activity in the DN had no effect on the appearance of activated STAT3 in the nucleus. These results show that the transport of activated Jak is not the main mechanism mediating retrograde signaling. Although there is an increase in phosphorylated STAT3 in the neurites after distal stimulation, the transport of activated STAT3 is not necessary for retrograde signaling. Our results are consistent with a signaling endosome model for retrograde signaling, in which the LIF/glycoprotein 130/LIF receptor/Jak complex is internalized and transported to activate STAT3 in the cell body.
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Affiliation(s)
- Jennifer J O'Brien
- Department of Pharmacology, University of Washington, Seattle, Washington, USA
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Lin MT, Lin BR, Chang CC, Chu CY, Su HJ, Chen ST, Jeng YM, Kuo ML. IL-6 induces AGS gastric cancer cell invasion via activation of the c-Src/RhoA/ROCK signaling pathway. Int J Cancer 2007; 120:2600-8. [PMID: 17304514 DOI: 10.1002/ijc.22599] [Citation(s) in RCA: 119] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Interleukin-6 (IL-6) is a multifunctional cytokine that is associated with the disease status and outcomes of gastric cancer. Nonetheless, the underlying mechanism of how IL-6 promotes the spread of gastric cancer is still unclear. In this study, we used a modified Boyden chamber assay to test the invasion ability of different gastric cancer cell lines. Liposome-mediated transfection was used to introduce an IL-6 expression vector into AGS cells, and the transfectants were further examined for the expression of active RhoA and phosphorylated Src using a pull-down assay and coimmunoprecipitation/Western blot analysis. Furthermore, RhoA expression in gastric adenocarcinoma specimens was investigated immunohistochemically. We documented that IL-6 could promote AGS cell motility and invasiveness, and inhibition of RhoA expression by dominant negative RhoA, C3 transferase, or dominant negative Src expressing plasmids could effectively decrease the invasiveness of IL-6 transfectants. We also documented an interaction between active RhoA and phosphorylated-Src following IL-6 treatment. Gastric cancers displaying high expression of RhoA are highly correlated with aggressive lymph node metastasis, more advanced tumor stage, histologically diffuse type and poorer survival. In conclusion, IL-6 induces AGS gastric cancer cell invasion via activation of the c-Src/RhoA/ROCK signaling pathway and RhoA expression could be used as a prognostic factor in patients with gastric adenocarcinoma.
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Affiliation(s)
- Ming-Tsan Lin
- Department of Primary Care Medicine, National Taiwan University Hospital, Taipei, Taiwan
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15
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Hausherr A, Tavares R, Schäffer M, Obermeier A, Miksch C, Mitina O, Ellwart J, Hallek M, Krause G. Inhibition of IL-6-dependent growth of myeloma cells by an acidic peptide repressing the gp130-mediated activation of Src family kinases. Oncogene 2007; 26:4987-98. [PMID: 17310994 DOI: 10.1038/sj.onc.1210306] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
An acidic domain (AD) of gp130 was previously found to interact with the Src family kinase (SFK) Hck. Here, the influence of myristoylated peptides derived from this AD was assessed in the mouse myeloma cell line, 7TD1. The IL-6-dependent growth of 7TD1 cells was reduced by approximately 75%, if 100 microM of myristoylated 18mer peptide (18AD) was included in the growth medium, but was unaffected by a control peptide with scrambled sequence (18sc). A similar differential inhibition by peptides 18AD and 18sc was observed for the erythropoietin-dependent growth of BaF-EH cells expressing chimeric erythropoietin receptor-gp130 and human Hck and for the human myeloma cell line INA-6. While the peptide 18AD concentration inhibiting 50% was approximately 30 microM in 7TD1 and BaF-EH cells, peptide 18AD did not significantly inhibit growth of IL-6-independent MM1.S myeloma and OKT1 hybridoma cells or of BaF-EH cells supplied with IL-3. Treatment with 100 microM peptide 18AD caused the same degree or 60% of apoptosis induction as IL-6 deprivation in 7TD1 or INA-6 cells, respectively. Co-immunoprecipitation experiments revealed that peptide 18AD interfered with the association of Hck and gp130 in 7TD1 lysates in a concentration-dependent manner. IL-6-treatment of INA-6 cells induced the kinase activities of Fyn, Lyn and Hck, but not Src, and the IL-6-induced SFK activities were inhibited by peptide 18AD. Expression in 7TD1 cells of a kinase-inactive Hck mutant (K269R) elicited a dominant-negative effect on cell number increases providing further evidence that SFKs are required for gp130 signalling in myeloma cells.
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Affiliation(s)
- A Hausherr
- Clinical Cooperation Group Gene Therapy, GSF National Research Center for Environment and Health, Munich, Germany
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16
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Arcaro A, Aubert M, Espinosa del Hierro ME, Khanzada UK, Angelidou S, Tetley TD, Bittermann AG, Frame MC, Seckl MJ. Critical role for lipid raft-associated Src kinases in activation of PI3K-Akt signalling. Cell Signal 2006; 19:1081-92. [PMID: 17275257 DOI: 10.1016/j.cellsig.2006.12.003] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2006] [Revised: 12/12/2006] [Accepted: 12/12/2006] [Indexed: 01/02/2023]
Abstract
Lipid rafts are membrane microdomains distinct from caveolae, whose functions in polypeptide growth factor signalling remain unclear. Here we show that in small cell lung cancer (SCLC) cells, specific growth factor receptors such as c-Kit associate with lipid rafts and that these domains play a critical role in the activation of phosphoinositide 3-kinase (PI3K) signalling. The class IA p85/p110alpha associated with Src in lipid rafts and was activated by Src in vitro. Lipid raft integrity was essential for Src activation in response to stem cell factor (SCF) and raft disruption selectively inhibited activation of protein kinase B (PKB)/Akt in response to SCF stimulation. Moreover, inhibition of Src kinases blocked PKB/Akt activation and SCLC cell growth. The use of fibroblasts with targeted deletion of the Src family kinase genes confirmed the role of Src kinases in PKB/Akt activation by growth factor receptors. Moreover a constitutively activated mutant of Src also stimulated PI3K/Akt in lipid rafts, indicating that these microdomains play a role in oncogenic signalling. Together our data demonstrate that lipid rafts play a key role in the activation of PI3K signalling by facilitating the interaction of Src with specific PI3K isoforms.
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Affiliation(s)
- Alexandre Arcaro
- Lung Cancer Biology Group, Division of Medicine, Imperial College Faculty of Medicine, Hammersmith Hospital Campus, Du Cane Road, London W12 ONN, United Kingdom.
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17
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Laszlo GS, Rosoff ML, Amieux PS, Nathanson NM. Multiple promoter elements required for leukemia inhibitory factor-stimulated M2 muscarinic acetylcholine receptor promoter activity. J Neurochem 2006; 98:1302-15. [PMID: 16800851 DOI: 10.1111/j.1471-4159.2006.03976.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Treatment of neuronal cells with leukemia inhibitory factor (LIF) results in increased M(2) muscarinic acetylcholine receptor promoter activity. We demonstrate here that multiple promoter elements mediate LIF stimulation of M(2) gene transcription. We identify a LIF inducible element (LIE) in the M(2) promoter with high homology to a cytokine-inducible ACTG-containing sequence in the vasoactive intestinal peptide promoter. Mutagenesis of both a STAT (signal transducers and activators of transcription) element and the LIE in the M(2) promoter is required to attenuate stimulation of M(2) promoter activity by LIF completely. Mobility shift assays indicate that a LIF-stimulated complex binds to a 70 base pair M(2) promoter fragment. Furthermore, a STAT element within this fragment can bind to LIF-stimulated nuclear STAT1 homodimers in vitro. Mutagenesis experiments show that cytokine-stimulated activation of M(2) promoter activity requires tyrosine residues on glycoprotein 130 (gp130) that are also required for both STAT1 and STAT3 activation. Dominant negative STAT1 or STAT3 can block LIF-stimulated M(2) promoter activity. Real-time RT-PCR analysis indicates that LIF-stimulated induction of M(2) mRNA is partially dependent on protein synthesis. These results show that regulation of M(2) gene transcription in neuronal cells by LIF occurs through a complex novel mechanism that is dependent on LIE, STAT and de novo protein synthesis.
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Affiliation(s)
- George S Laszlo
- Department of Pharmacology, University of Washington, School of Medicine, Seattle, 98195-7750, USA
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Wright LS, Prowse KR, Wallace K, Linskens MHK, Svendsen CN. Human progenitor cells isolated from the developing cortex undergo decreased neurogenesis and eventual senescence following expansion in vitro. Exp Cell Res 2006; 312:2107-20. [PMID: 16631163 DOI: 10.1016/j.yexcr.2006.03.012] [Citation(s) in RCA: 115] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2005] [Revised: 03/08/2006] [Accepted: 03/10/2006] [Indexed: 12/11/2022]
Abstract
Isolation of a true self-renewing stem cell from the human brain would be of great interest as a reliable source of neural tissue. Here, we report that human fetal cortical cells grown in epidermal growth factor expressed low levels of telomerase and telomeres in these cultures shortened over time leading to growth arrest after 30 weeks. Following leukemia inhibitory factor (LIF) supplementation, growth rates and telomerase expression increased. This was best demonstrated following cell cycle synchronization and staining for telomerase using immunocytochemistry. This increase in activity resulted in the maintenance of telomeres at approximately 7 kb for more than 60 weeks in vitro. However, all cultures displayed a lack of oligodendrotye production, decreases in neurogenesis over time and underwent replicative senescence associated with increased expression of p21 before 70 weeks in vitro. Thus, under our culture conditions, these cells are not stable, multipotent, telomerase expressing self-renewing stem cells. They may be more accurately described as human neural progenitor cells (hNPC) with limited lifespan and bi-potent potential (neurons/astrocytes). Interestingly, hNPC follow a course of proliferation, neuronal production and growth arrest similar to that seen during expansion and development of the human cortex, thus providing a possible model neural system. Furthermore, due to their high expansion potential and lack of tumorogenicity, these cells remain a unique and safe source of tissue for clinical transplantation.
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Affiliation(s)
- Lynda S Wright
- Waisman Center and Departments of Neurology and Anatomy University of Wisconsin-Madison, WI 53705-2280, USA
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Abstract
Signal transducer and activator of transcription 3 (STAT3) has long been shown to regulate gene transcription in response to cytokines and growth factors. Recent evidence suggests that STAT3 activation may also occur downstream of receptor-tyrosine kinase activation. In the current study we have identified STAT3 as a novel signal transducer for TrkA, the receptor-tyrosine kinase that mediates the functions of nerve growth factor (NGF). Activation of TrkA by NGF triggered STAT3 phosphorylation at Ser-727, and enhanced the DNA binding and transcriptional activities of STAT3. More importantly, neurotrophin-induced increase in STAT3 activation was observed to underlie several downstream functions of neurotrophin signaling. First of all, knockdown of STAT3 expression using the RNA interference approach attenuated NGF-induced transcription of immediate early genes in PC12 cells. Furthermore, reduced STAT3 expression in PC12 cells suppressed NGF-induced cyclin D1 expression, thereby inhibiting growth arrest normally triggered by NGF treatment. Finally, inhibition of STAT3 expression decreased brain-derived neurotrophic factor-promoted neurite outgrowth in primary hippocampal neurons. Together, our findings have identified STAT3 as an essential component of neurotrophin signaling and functions.
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Affiliation(s)
- Yu Pong Ng
- Department of Biochemistry, Biotechnology Research Institute, and Molecular Neuroscience Center, Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China
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20
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Böing I, Stross C, Radtke S, Lippok BE, Heinrich PC, Hermanns HM. Oncostatin M-induced activation of stress-activated MAP kinases depends on tyrosine 861 in the OSM receptor and requires Jak1 but not Src kinases. Cell Signal 2005; 18:50-61. [PMID: 15935618 DOI: 10.1016/j.cellsig.2005.03.015] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2005] [Revised: 03/11/2005] [Accepted: 03/15/2005] [Indexed: 11/16/2022]
Abstract
We have investigated the molecular mechanisms involved in the activation process of the stress-activated protein kinases (SAPK) p38 and JNK in response to the interleukin-6-type cytokine oncostatin M (OSM). Interestingly, activation of p38 and JNK originates from tyrosine residue 861 in the OSMR; the same tyrosine residue which we identified before to be involved in the activation of the mitogen-activated kinases Erk1/2 [Hermanns, H. M., Radtke, S., Schaper, F., Heinrich, P. C., and Behrmann, I. (2000) J. Biol. Chem. 275, 40742-40748]. Therefore, activation of members belonging to all three MAPK families is mediated by one tyrosine motif in the cytoplasmic region of the human OSMR. Concomitantly, point mutation of this residue abrogates the phosphorylation of these kinases. The Janus kinase Jak1 is absolutely essential for the activation of p38 in response to OSM, while Src kinase family members appear to be generally dispensable. Finally, we demonstrate that mutation of tyrosine 861 abrogates OSMR-mediated cell proliferation and identify Erk1/2 as mainly responsible for the proliferative effect. Erk1/2 activation is negatively influenced by p38 activation and inhibition of p38 significantly prolongs the half-life of OSM-induced Egr-1.
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Affiliation(s)
- Irene Böing
- Institut für Biochemie, Universitätsklinikum der Rheinisch-Westfälischen Technischen Hochschule Aachen, Pauwelsstr. 30, 52074 Aachen, Germany
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