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Delisle SV, Labreche C, Lara-Márquez M, Abou-Hamad J, Garland B, Lamarche-Vane N, Sabourin LA. Expression of a kinase inactive SLK is embryonic lethal and impairs cell migration in fibroblasts. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2024; 1871:119783. [PMID: 38871226 DOI: 10.1016/j.bbamcr.2024.119783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Revised: 06/03/2024] [Accepted: 06/06/2024] [Indexed: 06/15/2024]
Abstract
Kinases are known to have kinase activity independent functions. To gain further insights into potential kinase-independent functions of SLK/STK2, we have developed a kinase-dead allele, SLKK63R using in vivo CRISPR/Cas technology. Our studies show that blastocysts homozygote for SLKK63R do not develop into viable mice. However, heterozygotes are viable and fertile with no overt phenotypes. Analyses of mouse embryonic fibroblasts show that expression of SLKK63R results in a 50% decrease in kinase activity in heterozygotes. In contrast to previous studies, our data show that SLK does not form homodimers and that the kinase defective allele does not act in a dominant negative fashion. Expression of SLKK63R leads to altered Rac1 and RhoA activity, increased stress fiber formation and delayed focal adhesion turnover. Our data support a previously observed role for SLK in cell migration and suggest that at least 50% kinase activity is sufficient for embryonic development.
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Affiliation(s)
- Samuel V Delisle
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Cedrik Labreche
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Mónica Lara-Márquez
- Cancer Research Program, Research Institute of the McGill University Health Centre and Department of Anatomy and Cell Biology, McGill University, Montreal, QC, Canada
| | - John Abou-Hamad
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada; Dept. of Cancer Therapeutics, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Brennan Garland
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Nathalie Lamarche-Vane
- Cancer Research Program, Research Institute of the McGill University Health Centre and Department of Anatomy and Cell Biology, McGill University, Montreal, QC, Canada
| | - Luc A Sabourin
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada; Dept. of Cancer Therapeutics, Ottawa Hospital Research Institute, Ottawa, ON, Canada.
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2
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Al-Zahrani KN, Abou-Hamad J, Pascoal J, Labrèche C, Garland B, Sabourin LA. AKT-mediated phosphorylation of Sox9 induces Sox10 transcription in a murine model of HER2-positive breast cancer. Breast Cancer Res 2021; 23:55. [PMID: 33985544 PMCID: PMC8120776 DOI: 10.1186/s13058-021-01435-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Accepted: 05/05/2021] [Indexed: 02/07/2023] Open
Abstract
Background Approximately 5–10% of HER2-positive breast cancers can be defined by low expression of the Ste20-like kinase, SLK, and high expression of SOX10. Our lab has observed that genetic deletion of SLK results in the induction of Sox10 and significantly accelerates tumor initiation in a HER2-induced mammary tumor model. However, the mechanism responsible for the induction of SOX10 gene expression in this context remains unknown. Methods Using tumor-derived cell lines from MMTV-Neu mice lacking SLK and biochemical approaches, we have characterized the signaling mechanisms and relevant DNA elements driving Sox10 expression. Results Biochemical and genetic analyses of the SOX10 regulatory region in SLK-deficient mammary tumor cells show that Sox10 expression is dependent on a novel −7kb enhancer that harbors three SoxE binding sites. ChIP analyses demonstrate that Sox9 is bound to those elements in vivo. Our data show that AKT can directly phosphorylate Sox9 in vitro at serine 181 and that AKT inhibition blocks Sox9 phosphorylation and Sox10 expression in SLK(-/-) tumor cells. AKT-mediated Sox9 phosphorylation increases its transcriptional activity on the Sox10 −7kb enhancer without altering its DNA-binding activity. Interestingly, analysis of murine and human mammary tumors reveals a direct correlation between the levels of active phospho-Sox9 S181 and Sox10 expression. Conclusions Our results have identified a novel Sox10 enhancer and validated Sox9 as a direct target for AKT. As Sox10 is a biomarker for triple-negative breast cancers (TNBC), these findings might have major implications in the targeting and treatment of those cancers. Supplementary Information The online version contains supplementary material available at 10.1186/s13058-021-01435-6.
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Affiliation(s)
- Khalid N Al-Zahrani
- Centre for Cancer Therapeutics, Ottawa Hospital Research Institute, 501 Smyth Road, Ottawa, ON, K1H 8L6, Canada.,Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, K1H 8M5, Canada
| | - John Abou-Hamad
- Centre for Cancer Therapeutics, Ottawa Hospital Research Institute, 501 Smyth Road, Ottawa, ON, K1H 8L6, Canada.,Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, K1H 8M5, Canada
| | - Julia Pascoal
- Centre for Cancer Therapeutics, Ottawa Hospital Research Institute, 501 Smyth Road, Ottawa, ON, K1H 8L6, Canada
| | - Cédrik Labrèche
- Centre for Cancer Therapeutics, Ottawa Hospital Research Institute, 501 Smyth Road, Ottawa, ON, K1H 8L6, Canada.,Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, K1H 8M5, Canada
| | - Brennan Garland
- Centre for Cancer Therapeutics, Ottawa Hospital Research Institute, 501 Smyth Road, Ottawa, ON, K1H 8L6, Canada.,Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, K1H 8M5, Canada
| | - Luc A Sabourin
- Centre for Cancer Therapeutics, Ottawa Hospital Research Institute, 501 Smyth Road, Ottawa, ON, K1H 8L6, Canada. .,Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, K1H 8M5, Canada.
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3
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Garland B, Delisle S, Al-Zahrani KN, Pryce BR, Sabourin LA. The Ste20-like kinase - a Jack of all trades? J Cell Sci 2021; 134:261804. [PMID: 33961052 DOI: 10.1242/jcs.258269] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Over the past 20 years, the Ste20-like kinase (SLK; also known as STK2) has emerged as a central regulator of cytoskeletal dynamics. Reorganization of the cytoskeleton is necessary for a plethora of biological processes including apoptosis, proliferation, migration, tissue repair and signaling. Several studies have also uncovered a role for SLK in disease progression and cancer. Here, we review the recent findings in the SLK field and summarize the various roles of SLK in different animal models and discuss the biochemical mechanisms regulating SLK activity. Together, these studies have revealed multiple roles for SLK in coupling cytoskeletal dynamics to cell growth, in muscle repair and in negative-feedback loops critical for cancer progression. Furthermore, the ability of SLK to regulate some systems appears to be kinase activity independent, suggesting that it may be an important scaffold for signal transduction pathways. These various findings reveal highly complex functions and regulation patterns of SLK in development and disease, making it a potential therapeutic target.
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Affiliation(s)
- Brennan Garland
- Ottawa Hospital Research Institute, Cancer Therapeutics, Ottawa, Ontario, K1H8L1, Canada.,Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, K1H8L6, Canada
| | - Samuel Delisle
- Ottawa Hospital Research Institute, Cancer Therapeutics, Ottawa, Ontario, K1H8L1, Canada.,Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, K1H8L6, Canada
| | - Khalid N Al-Zahrani
- Center for Molecular and Systems Biology, Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, M5G1X5, Canada
| | - Benjamin R Pryce
- Department of Pediatrics, Hollings Cancer Center, Medical University of South Carolina,Charleston, SC 29425, USA
| | - Luc A Sabourin
- Ottawa Hospital Research Institute, Cancer Therapeutics, Ottawa, Ontario, K1H8L1, Canada.,Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, K1H8L6, Canada
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4
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Villemin JP, Lorenzi C, Cabrillac MS, Oldfield A, Ritchie W, Luco RF. A cell-to-patient machine learning transfer approach uncovers novel basal-like breast cancer prognostic markers amongst alternative splice variants. BMC Biol 2021; 19:70. [PMID: 33845831 PMCID: PMC8042689 DOI: 10.1186/s12915-021-01002-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 03/09/2021] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Breast cancer is amongst the 10 first causes of death in women worldwide. Around 20% of patients are misdiagnosed leading to early metastasis, resistance to treatment and relapse. Many clinical and gene expression profiles have been successfully used to classify breast tumours into 5 major types with different prognosis and sensitivity to specific treatments. Unfortunately, these profiles have failed to subclassify breast tumours into more subtypes to improve diagnostics and survival rate. Alternative splicing is emerging as a new source of highly specific biomarkers to classify tumours in different grades. Taking advantage of extensive public transcriptomics datasets in breast cancer cell lines (CCLE) and breast cancer tumours (TCGA), we have addressed the capacity of alternative splice variants to subclassify highly aggressive breast cancers. RESULTS Transcriptomics analysis of alternative splicing events between luminal, basal A and basal B breast cancer cell lines identified a unique splicing signature for a subtype of tumours, the basal B, whose classification is not in use in the clinic yet. Basal B cell lines, in contrast with luminal and basal A, are highly metastatic and express epithelial-to-mesenchymal (EMT) markers, which are hallmarks of cell invasion and resistance to drugs. By developing a semi-supervised machine learning approach, we transferred the molecular knowledge gained from these cell lines into patients to subclassify basal-like triple negative tumours into basal A- and basal B-like categories. Changes in splicing of 25 alternative exons, intimately related to EMT and cell invasion such as ENAH, CD44 and CTNND1, were sufficient to identify the basal-like patients with the worst prognosis. Moreover, patients expressing this basal B-specific splicing signature also expressed newly identified biomarkers of metastasis-initiating cells, like CD36, supporting a more invasive phenotype for this basal B-like breast cancer subtype. CONCLUSIONS Using a novel machine learning approach, we have identified an EMT-related splicing signature capable of subclassifying the most aggressive type of breast cancer, which are basal-like triple negative tumours. This proof-of-concept demonstrates that the biological knowledge acquired from cell lines can be transferred to patients data for further clinical investigation. More studies, particularly in 3D culture and organoids, will increase the accuracy of this transfer of knowledge, which will open new perspectives into the development of novel therapeutic strategies and the further identification of specific biomarkers for drug resistance and cancer relapse.
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Affiliation(s)
- Jean-Philippe Villemin
- Institut de Génétique Humaine (IGH-UMR9002), Centre National de la Recherche Scientifique (CNRS), University of Montpellier, Montpellier, France
| | - Claudio Lorenzi
- Institut de Génétique Humaine (IGH-UMR9002), Centre National de la Recherche Scientifique (CNRS), University of Montpellier, Montpellier, France
| | - Marie-Sarah Cabrillac
- Institut de Génétique Humaine (IGH-UMR9002), Centre National de la Recherche Scientifique (CNRS), University of Montpellier, Montpellier, France
| | - Andrew Oldfield
- Institut de Génétique Humaine (IGH-UMR9002), Centre National de la Recherche Scientifique (CNRS), University of Montpellier, Montpellier, France
| | - William Ritchie
- Institut de Génétique Humaine (IGH-UMR9002), Centre National de la Recherche Scientifique (CNRS), University of Montpellier, Montpellier, France.
| | - Reini F Luco
- Institut de Génétique Humaine (IGH-UMR9002), Centre National de la Recherche Scientifique (CNRS), University of Montpellier, Montpellier, France.
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5
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Pryce BR, Labrèche C, Hamoudi D, Abou-Hamad J, Al-Zahrani KN, Hodgins JJ, Boulanger-Piette A, Bossé S, Balog-Alvarez C, Frénette J, Ardolino M, Kornegay JN, Sabourin LA. Muscle-specific deletion of SLK/Stk2 enhances p38 activity and myogenesis in mdx mice. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2020; 1868:118917. [PMID: 33259860 DOI: 10.1016/j.bbamcr.2020.118917] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 11/23/2020] [Accepted: 11/25/2020] [Indexed: 01/17/2023]
Abstract
Duchenne's muscular dystrophy (DMD) is a severe muscle wasting disorder characterized by the loss of dystrophin expression, muscle necrosis, inflammation and fibrosis. Ongoing muscle regeneration is impaired by persistent cytokine stress, further decreasing muscle function. Patients with DMD rarely survive beyond their early 20s, with cardiac and respiratory dysfunction being the primary cause of death. Despite an increase in our understanding of disease progression as well as promising preclinical animal models for therapeutic intervention, treatment options for muscular dystrophy remain limited and novel therapeutic targets are required. Many reports suggest that the TGFβ signalling pathway is activated in dystrophic muscle and contributes to the pathology of DMD in part by impairing the differentiation of myoblasts into mature myofibers. Here, we show that in vitro knockdown of the Ste20-like kinase, SLK, can partially restore myoblast differentiation downstream of TGFβ in a Smad2/3 independent manner. In an mdx model, we demonstrate that SLK is expressed at high levels in regenerating myofibers. Muscle-specific deletion of SLK reduced leukocyte infiltration, increased myogenin and utrophin expression and enhanced differentiation. This was accompanied by resistance to eccentric contraction-induced injury in slow fiber type-enriched soleus muscles. Finally, we found that these effects were partially dependent on the upregulation of p38 signalling. Collectively, these results demonstrate that SLK downregulation can restore some aspects of disease progression in DMD.
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Affiliation(s)
- Benjamin R Pryce
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada; Cancer Therapeutics Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Cédrik Labrèche
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada; Cancer Therapeutics Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Dounia Hamoudi
- Centre de Recherche du Centre Hospitalier Universitaire de Québec-Centre Hospitalier de L'Université Laval, Université Laval, Quebec City, Quebec, Canada
| | - John Abou-Hamad
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada; Cancer Therapeutics Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Khalid N Al-Zahrani
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada; Cancer Therapeutics Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Jonathan J Hodgins
- Cancer Therapeutics Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada; Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Antoine Boulanger-Piette
- Centre de Recherche du Centre Hospitalier Universitaire de Québec-Centre Hospitalier de L'Université Laval, Université Laval, Quebec City, Quebec, Canada
| | - Sabrina Bossé
- Centre de Recherche du Centre Hospitalier Universitaire de Québec-Centre Hospitalier de L'Université Laval, Université Laval, Quebec City, Quebec, Canada
| | - Cindy Balog-Alvarez
- Department of Veterinary Integrative Biosciences, Texas A&M University College of Veterinary Medicine & Biomedical Sciences, College Station, TX, USA
| | - Jérôme Frénette
- Centre de Recherche du Centre Hospitalier Universitaire de Québec-Centre Hospitalier de L'Université Laval, Université Laval, Quebec City, Quebec, Canada; Département de Réadaptation, Faculté de Médecine, Université Laval, Quebec City, Quebec, Canada
| | - Michele Ardolino
- Cancer Therapeutics Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada; Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada
| | - Joe N Kornegay
- Department of Veterinary Integrative Biosciences, Texas A&M University College of Veterinary Medicine & Biomedical Sciences, College Station, TX, USA
| | - Luc A Sabourin
- Department of Cellular and Molecular Medicine, Faculty of Medicine, University of Ottawa, Ottawa, ON, Canada; Cancer Therapeutics Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada.
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6
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Loss of the Ste20-like kinase induces a basal/stem-like phenotype in HER2-positive breast cancers. Oncogene 2020; 39:4592-4602. [PMID: 32393835 DOI: 10.1038/s41388-020-1315-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 04/22/2020] [Accepted: 04/24/2020] [Indexed: 01/20/2023]
Abstract
HER2 is overexpressed in 20-30% of all breast cancers and is associated with an invasive disease and poor clinical outcome. The Ste20-like kinase (SLK) is activated downstream of HER2/Neu and is required for efficient epithelial-to-mesenchymal transition, cell cycle progression, and migration in the mammary epithelium. Here we show that loss of SLK in a murine model of HER2/Neu-positive breast cancers significantly accelerates tumor onset and decreases overall survival. Transcriptional profiling of SLK knockout HER2/Neu-derived tumor cells revealed a strong induction in the triple-negative breast cancer marker, Sox10, accompanied by an increase in mammary stem/progenitor activity. Similarly, we demonstrate that SLK and Sox10 expression are inversely correlated in patient samples, with the loss of SLK and acquisition of Sox10 marking the triple-negative subtype. Furthermore, pharmacological inhibition of AKT reduces SLK-null tumor growth in vivo and is rescued by ectopic Sox10 expression, suggesting that Sox10 is a critical regulator of tumor growth downstream of SLK/AKT. These findings highlight a role for SLK in negatively regulating HER2-induced mammary tumorigenesis and provide mechanistic insight into the regulation of Sox10 expression in breast cancer.
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7
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Gao N, Li J, Qin Y, Wang Y, Kang Q, Pei C. SNAI1 interacts with HDAC1 to control TGF‑β2‑induced epithelial‑mesenchymal transition in human lens epithelial cells. Int J Mol Med 2019; 45:265-273. [PMID: 31746377 DOI: 10.3892/ijmm.2019.4405] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2019] [Accepted: 09/03/2019] [Indexed: 11/06/2022] Open
Abstract
The opacity of the lens capsule after cataract surgery is caused by epithelial‑to‑mesenchymal transition (EMT) of lens epithelial cells. Snail family transcriptional repressor 1 (SNAI1) is a transcriptional repressor that recruits multiple chromatin enzymes including lysine‑specific histone demethylase 1A, histone deacetylase (HDAC) 1/2, polycomb repressive complex 2, euchromatic histone lysine methyltransferase 2 and suppressor of variegation 3‑9 homolog 1 to the E‑cadherin promoter, thereby suppressing E‑cadherin expression. However, the functional relationship between SNAI1 and HDAC in the induction of EMT in human lens epithelial cells (HLECs) is still unclear. Therefore, the objective of the present study was to explore the possible functional relationship between SNAI1 and HDAC1 in the induction of EMT in HLECs. In the present study, SNAI1 was found to be increased in HLECs during transforming growth factor‑β2 (TGF‑β2)‑induced EMT. Knockdown of SNAI1 by siRNA reversed TGF‑β2‑induced downregulation of E‑cadherin and upregulation of α‑Smooth Muscle Actin. Furthermore, SNAI1 was found to be associated with HDAC1 in the E‑cadherin promoter in TGF‑β2‑treated HLECs. Inhibition of HDAC by trichostatin A and suberoylanilide hydroxamic acid could prevent TGF‑β2‑induced EMT in HLECs. Collectively, SNAI1 interacted with HDAC1 to repress E‑cadherin in the TGF‑β2‑induced EMT in HLECs, suggesting that HDAC inhibitors may have potential therapeutic value for the prevention of EMT in HLECs.
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Affiliation(s)
- Ning Gao
- Department of Ophthalmology, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China
| | - Jingming Li
- Department of Ophthalmology, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China
| | - Yazhou Qin
- Department of Ophthalmology, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China
| | - Yingna Wang
- Department of Ophthalmology, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China
| | - Qianyang Kang
- Department of Ophthalmology, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China
| | - Cheng Pei
- Department of Ophthalmology, First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi 710061, P.R. China
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8
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Kumar D, Das M, Sauceda C, Ellies LG, Kuo K, Parwal P, Kaur M, Jih L, Bandyopadhyay GK, Burton D, Loomba R, Osborn O, Webster NJ. Degradation of splicing factor SRSF3 contributes to progressive liver disease. J Clin Invest 2019; 129:4477-4491. [PMID: 31393851 DOI: 10.1172/jci127374] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Serine rich splicing factor 3 (SRSF3) plays a critical role in liver function and its loss promotes chronic liver damage and regeneration. As a consequence, genetic deletion of SRSF3 in hepatocytes caused progressive liver disease and ultimately led to hepatocellular carcinoma. Here we show that SRSF3 is decreased in human liver samples with non-alcoholic fatty liver disease (NAFLD), non-alcoholic steatohepatitis (NASH), or cirrhosis that was associated with alterations in RNA splicing of known SRSF3 target genes. Hepatic SRSF3 expression was similarly decreased and RNA splicing dysregulated in mouse models of NAFLD and NASH. We showed that palmitic acid-induced oxidative stress caused conjugation of the ubiquitin like NEDD8 protein to SRSF3 and proteasome mediated degradation. SRSF3 was selectively neddylated at lysine11 and mutation of this residue (SRSF3-K11R) was sufficient to prevent both SRSF3 degradation and alterations in RNA splicing. Finally prevention of SRSF3 degradation in vivo partially protected mice from hepatic steatosis, fibrosis and inflammation. These results highlight a neddylation-dependent mechanism regulating gene expression in the liver that is disrupted in early metabolic liver disease and may contribute to the progression to NASH, cirrhosis and ultimately hepatocellular carcinoma.
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Affiliation(s)
- Deepak Kumar
- VA San Diego Healthcare System, San Diego, California, USA.,Department of Medicine
| | | | - Consuelo Sauceda
- VA San Diego Healthcare System, San Diego, California, USA.,Department of Medicine
| | - Lesley G Ellies
- Department of Pathology, and.,Moores Cancer Center, UCSD, La Jolla, California, USA
| | | | | | | | - Lily Jih
- VA San Diego Healthcare System, San Diego, California, USA
| | | | - Douglas Burton
- VA San Diego Healthcare System, San Diego, California, USA
| | - Rohit Loomba
- Department of Medicine.,Moores Cancer Center, UCSD, La Jolla, California, USA
| | | | - Nicholas Jg Webster
- VA San Diego Healthcare System, San Diego, California, USA.,Department of Medicine.,Moores Cancer Center, UCSD, La Jolla, California, USA
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9
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The LIM domain binding protein 1, Ldb1, has distinct roles in Neu-induced mammary tumorigenesis. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2018; 1865:1590-1597. [DOI: 10.1016/j.bbamcr.2018.08.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Revised: 08/07/2018] [Accepted: 08/14/2018] [Indexed: 01/15/2023]
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10
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Yang BL, Zhu P, Li YR, Xu MM, Wang H, Qiao LC, Xu HX, Chen HJ. Total flavone of Abelmoschus manihot suppresses epithelial-mesenchymal transition via interfering transforming growth factor-β1 signaling in Crohn’s disease intestinal fibrosis. World J Gastroenterol 2018; 24:3414-3425. [PMID: 30122880 PMCID: PMC6092575 DOI: 10.3748/wjg.v24.i30.3414] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 06/27/2018] [Accepted: 06/28/2018] [Indexed: 02/06/2023] Open
Abstract
AIM To explore the role and mechanism of total flavone of Abelmoschus manihot (TFA) on epithelial-mesenchymal transition (EMT) progress of Crohn’s disease (CD) intestinal fibrosis.
METHODS First, CCK-8 assay was performed to assess TFA on the viability of intestinal epithelial (IEC-6) cells and select the optimal concentrations of TFA for our further studies. Then cell morphology, wound healing and transwell assays were performed to examine the effect of TFA on morphology, migration and invasion of IEC-6 cells treated with TGF-β1. In addition, immunofluorescence, real-time PCR analysis (qRT-PCR) and western blotting assays were carried out to detect the impact of TFA on EMT progress. Moreover, western blotting assay was performed to evaluate the function of TFA on the Smad and MAPK signaling pathways. Further, the role of co-treatment of TFA and si-Smad or MAPK inhibitors has been examined by qRT-PCR, western blotting, morphology, wound healing and transwell assays.
RESULTS In this study, TFA promoted transforming growth factor-β1 (TGF-β1)-induced (IEC-6) morphological change, migration and invasion, and increased the expression of epithelial markers and reduced the levels of mesenchymal markers, along with the inactivation of Smad and MAPK signaling pathways. Moreover, we revealed that si-Smad and MAPK inhibitors effectively attenuated TGF-β1-induced EMT in IEC-6 cells. Importantly, co-treatment of TFA and si-Smad or MAPK inhibitors had better inhibitory effects on TGF-β1-induced EMT in IEC-6 cells than either one of them.
CONCLUSION These findings could provide new insight into the molecular mechanisms of TFA on TGF-β1-induced EMT in IEC-6 cells and TFA is expected to advance as a new therapy to treat CD intestinal fibrosis.
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Affiliation(s)
- Bo-Lin Yang
- Department of Colorectal Surgery, The Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing 210029, Jiangsu Province, China
| | - Ping Zhu
- Department of Colorectal Surgery, The Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing 210029, Jiangsu Province, China
| | - You-Ran Li
- Department of Colorectal Surgery, The Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing 210029, Jiangsu Province, China
| | - Min-Min Xu
- Department of Colorectal Surgery, The Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing 210029, Jiangsu Province, China
| | - Hao Wang
- Department of Colorectal Surgery, The Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing 210029, Jiangsu Province, China
| | - Li-Chao Qiao
- Department of Colorectal Surgery, The Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing 210029, Jiangsu Province, China
| | - Hai-Xia Xu
- Department of Colorectal Surgery, The Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing 210029, Jiangsu Province, China
| | - Hong-Jin Chen
- Department of Colorectal Surgery, The Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing 210029, Jiangsu Province, China
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