1
|
Bolduan V, Palzer KA, Hieber C, Schunke J, Fichter M, Schneider P, Grabbe S, Pautz A, Bros M. The mRNA-Binding Protein KSRP Limits the Inflammatory Response of Macrophages. Int J Mol Sci 2024; 25:3884. [PMID: 38612694 PMCID: PMC11011855 DOI: 10.3390/ijms25073884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Revised: 03/27/2024] [Accepted: 03/29/2024] [Indexed: 04/14/2024] Open
Abstract
KH-type splicing regulatory protein (KSRP) is a single-stranded nucleic acid-binding protein with multiple functions. It is known to bind AU-rich motifs within the 3'-untranslated region of mRNA species, which in many cases encode dynamically regulated proteins like cytokines. In the present study, we investigated the role of KSRP for the immunophenotype of macrophages using bone marrow-derived macrophages (BMDM) from wild-type (WT) and KSRP-/- mice. RNA sequencing revealed that KSRP-/- BMDM displayed significantly higher mRNA expression levels of genes involved in inflammatory and immune responses, particularly type I interferon responses, following LPS stimulation. In line, time kinetics studies revealed increased levels of interferon-γ (IFN-γ), interleukin (IL)-1β and IL-6 mRNA in KSRP-/- macrophages after 6 h subsequent to LPS stimulation as compared to WT cultures. At the protein level, KSRP-/- BMDM displayed higher levels of these cytokines after overnight stimulation. Matching results were observed for primary peritoneal macrophages of KSRP-/- mice. These showed higher IL-6, tumor necrosis factor-α (TNF-α), C-X-C motif chemokine 1 (CXCL1) and CC-chemokine ligand 5 (CCL5) protein levels in response to LPS stimulation than the WT controls. As macrophages play a key role in sepsis, the in vivo relevance of KSRP deficiency for cytokine/chemokine production was analyzed in an acute inflammation model. In agreement with our in vitro findings, KSRP-deficient animals showed higher cytokine production upon LPS administration in comparison to WT mice. Taken together, these findings demonstrate that KSRP constitutes an important negative regulator of cytokine expression in macrophages.
Collapse
Affiliation(s)
- Vanessa Bolduan
- Department of Dermatology, University Medical Center, Langenbeckstr. 1, 55131 Mainz, Germany
| | - Kim-Alicia Palzer
- Department of Pharmacology, University Medical Center, Langenbeckstr. 1, 55131 Mainz, Germany (A.P.)
| | - Christoph Hieber
- Department of Dermatology, University Medical Center, Langenbeckstr. 1, 55131 Mainz, Germany
| | - Jenny Schunke
- Department of Dermatology, University Medical Center, Langenbeckstr. 1, 55131 Mainz, Germany
| | - Michael Fichter
- Department of Dermatology, University Medical Center, Langenbeckstr. 1, 55131 Mainz, Germany
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Paul Schneider
- Department of Dermatology, University Medical Center, Langenbeckstr. 1, 55131 Mainz, Germany
| | - Stephan Grabbe
- Department of Dermatology, University Medical Center, Langenbeckstr. 1, 55131 Mainz, Germany
| | - Andrea Pautz
- Department of Pharmacology, University Medical Center, Langenbeckstr. 1, 55131 Mainz, Germany (A.P.)
| | - Matthias Bros
- Department of Dermatology, University Medical Center, Langenbeckstr. 1, 55131 Mainz, Germany
| |
Collapse
|
2
|
Leavenworth JD, Yusuf N, Hassan Q. K-Homology Type Splicing Regulatory Protein: Mechanism of Action in Cancer and Immune Disorders. Crit Rev Eukaryot Gene Expr 2024; 34:75-87. [PMID: 37824394 PMCID: PMC11003564 DOI: 10.1615/critreveukaryotgeneexpr.2023048085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2023]
Abstract
K homology-type splicing regulatory protein (KSRP) is emerging as a key player in cancer biology, and immunology. As a single-strand nucleic acid binding protein it functions in both transcriptional and post-transcriptional regulation, while facilitating multiple stages of RNA metabolism to affect proliferation and control cell fate. However, it must interact with other proteins to determine the fate of its bound substrate. Here we provide an minireview of this important regulatory protein and describe its complex subcellular functions to affect RNA metabolism, stability, miRNA biogenesis and maturation, stress granule function, metastasis, and inflammatory processes.
Collapse
Affiliation(s)
- Jonathan D. Leavenworth
- Department of Oral and Maxillofacial Surgery, Institute of Oral Health Research, School of Dentistry, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Nabiha Yusuf
- Department of Dermatology, Heersink School of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Quamarul Hassan
- Department of Oral and Maxillofacial Surgery, Institute of Oral Health Research, School of Dentistry, University of Alabama at Birmingham, Birmingham, AL, USA
| |
Collapse
|
3
|
Schuster SL, Arora S, Wladyka CL, Itagi P, Corey L, Young D, Stackhouse BL, Kollath L, Wu QV, Corey E, True LD, Ha G, Paddison PJ, Hsieh AC. Multi-level functional genomics reveals molecular and cellular oncogenicity of patient-based 3' untranslated region mutations. Cell Rep 2023; 42:112840. [PMID: 37516102 PMCID: PMC10540565 DOI: 10.1016/j.celrep.2023.112840] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 06/05/2023] [Accepted: 07/05/2023] [Indexed: 07/31/2023] Open
Abstract
3' untranslated region (3' UTR) somatic mutations represent a largely unexplored avenue of alternative oncogenic gene dysregulation. To determine the significance of 3' UTR mutations in disease, we identify 3' UTR somatic variants across 185 advanced prostate tumors, discovering 14,497 single-nucleotide mutations enriched in oncogenic pathways and 3' UTR regulatory elements. By developing two complementary massively parallel reporter assays, we measure how thousands of patient-based mutations affect mRNA translation and stability and identify hundreds of functional variants that allow us to define determinants of mutation significance. We demonstrate the clinical relevance of these mutations, observing that CRISPR-Cas9 endogenous editing of distinct variants increases cellular stress resistance and that patients harboring oncogenic 3' UTR mutations have a particularly poor prognosis. This work represents an expansive view of the extent to which disease-relevant 3' UTR mutations affect mRNA stability, translation, and cancer progression, uncovering principles of regulatory functionality and potential therapeutic targets in previously unexplored regulatory regions.
Collapse
Affiliation(s)
- Samantha L Schuster
- Molecular and Cellular Biology Graduate Program, University of Washington, Seattle, WA 98195, USA; Human Biology Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Sonali Arora
- Human Biology Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Cynthia L Wladyka
- Human Biology Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Pushpa Itagi
- Human Biology Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA; Public Health Sciences Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Lukas Corey
- Human Biology Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Dave Young
- Human Biology Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | | | - Lori Kollath
- Department of Urology, University of Washington, Seattle, WA 98195, USA
| | - Qian V Wu
- Clinical Research Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Eva Corey
- Department of Urology, University of Washington, Seattle, WA 98195, USA
| | - Lawrence D True
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA 98195, USA
| | - Gavin Ha
- Public Health Sciences Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA; Department of Genome Sciences, University of Washington, Seattle, WA 98195, USA
| | - Patrick J Paddison
- Molecular and Cellular Biology Graduate Program, University of Washington, Seattle, WA 98195, USA; Human Biology Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Andrew C Hsieh
- Molecular and Cellular Biology Graduate Program, University of Washington, Seattle, WA 98195, USA; Human Biology Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA; Department of Genome Sciences, University of Washington, Seattle, WA 98195, USA; Department of Medicine, University of Washington, Seattle, WA 98195, USA.
| |
Collapse
|
4
|
Mehta M, Raguraman R, Ramesh R, Munshi A. RNA binding proteins (RBPs) and their role in DNA damage and radiation response in cancer. Adv Drug Deliv Rev 2022; 191:114569. [PMID: 36252617 PMCID: PMC10411638 DOI: 10.1016/j.addr.2022.114569] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 09/27/2022] [Accepted: 09/29/2022] [Indexed: 01/24/2023]
Abstract
Traditionally majority of eukaryotic gene expression is influenced by transcriptional and post-transcriptional events. Alterations in the expression of proteins that act post-transcriptionally can affect cellular signaling and homeostasis. RNA binding proteins (RBPs) are a family of proteins that specifically bind to RNAs and are involved in post-transcriptional regulation of gene expression and important cellular processes such as cell differentiation and metabolism. Deregulation of RNA-RBP interactions and any changes in RBP expression or function can lead to various diseases including cancer. In cancer cells, RBPs play an important role in regulating the expression of tumor suppressors and oncoproteins involved in various cell-signaling pathways. Several RBPs such as HuR, AUF1, RBM38, LIN28, RBM24, tristetrapolin family and Musashi play critical roles in various types of cancers and their aberrant expression in cancer cells makes them an attractive therapeutic target for cancer treatment. In this review we provide an overview of i). RBPs involved in cancer progression and their mechanism of action ii). the role of RBPs, including HuR, in breast cancer progression and DNA damage response and iii). explore RBPs with emphasis on HuR as therapeutic target for breast cancer therapy.
Collapse
Affiliation(s)
- Meghna Mehta
- Department of Radiation Oncology, The University of Oklahoma Health Sciences Center, Oklahoma City, OK 73013, USA; Stephenson Cancer Center, The University of Oklahoma Health Sciences Center, Oklahoma City, OK 73013, USA
| | - Rajeswari Raguraman
- Department of Pathology, The University of Oklahoma Health Sciences Center, Oklahoma City, OK 73013, USA; Stephenson Cancer Center, The University of Oklahoma Health Sciences Center, Oklahoma City, OK 73013, USA
| | - Rajagopal Ramesh
- Department of Pathology, The University of Oklahoma Health Sciences Center, Oklahoma City, OK 73013, USA; Stephenson Cancer Center, The University of Oklahoma Health Sciences Center, Oklahoma City, OK 73013, USA
| | - Anupama Munshi
- Department of Radiation Oncology, The University of Oklahoma Health Sciences Center, Oklahoma City, OK 73013, USA; Stephenson Cancer Center, The University of Oklahoma Health Sciences Center, Oklahoma City, OK 73013, USA.
| |
Collapse
|
5
|
RNA-Binding Proteins in the Regulation of Adipogenesis and Adipose Function. Cells 2022; 11:cells11152357. [PMID: 35954201 PMCID: PMC9367552 DOI: 10.3390/cells11152357] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2022] [Revised: 07/28/2022] [Accepted: 07/29/2022] [Indexed: 01/27/2023] Open
Abstract
The obesity epidemic represents a critical public health issue worldwide, as it is a vital risk factor for many diseases, including type 2 diabetes (T2D) and cardiovascular disease. Obesity is a complex disease involving excessive fat accumulation. Proper adipose tissue accumulation and function are highly transcriptional and regulated by many genes. Recent studies have discovered that post-transcriptional regulation, mainly mediated by RNA-binding proteins (RBPs), also plays a crucial role. In the lifetime of RNA, it is bound by various RBPs that determine every step of RNA metabolism, from RNA processing to alternative splicing, nucleus export, rate of translation, and finally decay. In humans, it is predicted that RBPs account for more than 10% of proteins based on the presence of RNA-binding domains. However, only very few RBPs have been studied in adipose tissue. The primary aim of this paper is to provide an overview of RBPs in adipogenesis and adipose function. Specifically, the following best-characterized RBPs will be discussed, including HuR, PSPC1, Sam68, RBM4, Ybx1, Ybx2, IGF2BP2, and KSRP. Characterization of these proteins will increase our understanding of the regulatory mechanisms of RBPs in adipogenesis and provide clues for the etiology and pathology of adipose-tissue-related diseases.
Collapse
|
6
|
Palzer KA, Bolduan V, Käfer R, Kleinert H, Bros M, Pautz A. The Role of KH-Type Splicing Regulatory Protein (KSRP) for Immune Functions and Tumorigenesis. Cells 2022; 11:cells11091482. [PMID: 35563788 PMCID: PMC9104899 DOI: 10.3390/cells11091482] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 04/21/2022] [Accepted: 04/26/2022] [Indexed: 12/11/2022] Open
Abstract
Post-transcriptional control of gene expression is one important mechanism that enables stringent and rapid modulation of cytokine, chemokines or growth factors expression, all relevant for immune or tumor cell function and communication. The RNA-binding protein KH-type splicing regulatory protein (KSRP) controls the mRNA stability of according genes by initiation of mRNA decay and inhibition of translation, and by enhancing the maturation of microRNAs. Therefore, KSRP plays a pivotal role in immune cell function and tumor progression. In this review, we summarize the current knowledge about KSRP with regard to the regulation of immunologically relevant targets, and the functional role of KSRP on immune responses and tumorigenesis. KSRP is involved in the control of myeloid hematopoiesis. Further, KSRP-mediated mRNA decay of pro-inflammatory factors is necessary to keep immune homeostasis. In case of infection, functional impairment of KSRP is important for the induction of robust immune responses. In this regard, KSRP seems to primarily dampen T helper cell 2 immune responses. In cancer, KSRP has often been associated with tumor growth and metastasis. In summary, aside of initiation of mRNA decay, the KSRP-mediated regulation of microRNA maturation seems to be especially important for its diverse biological functions, which warrants further in-depth examination.
Collapse
Affiliation(s)
- Kim-Alicia Palzer
- Department of Pharmacology, University Medical Center of the Johannes Gutenberg University Mainz, 55131 Mainz, Germany; (K.-A.P.); (R.K.); (H.K.)
| | - Vanessa Bolduan
- Department of Dermatology, University Medical Center of the Johannes Gutenberg University Mainz, 55131 Mainz, Germany; (V.B.); (M.B.)
| | - Rudolf Käfer
- Department of Pharmacology, University Medical Center of the Johannes Gutenberg University Mainz, 55131 Mainz, Germany; (K.-A.P.); (R.K.); (H.K.)
| | - Hartmut Kleinert
- Department of Pharmacology, University Medical Center of the Johannes Gutenberg University Mainz, 55131 Mainz, Germany; (K.-A.P.); (R.K.); (H.K.)
| | - Matthias Bros
- Department of Dermatology, University Medical Center of the Johannes Gutenberg University Mainz, 55131 Mainz, Germany; (V.B.); (M.B.)
| | - Andrea Pautz
- Department of Pharmacology, University Medical Center of the Johannes Gutenberg University Mainz, 55131 Mainz, Germany; (K.-A.P.); (R.K.); (H.K.)
- Correspondence: ; Tel.: +49-6131-179276; Fax: +49-6131-179042
| |
Collapse
|
7
|
Guha A, Waris S, Nabors LB, Filippova N, Gorospe M, Kwan T, King PH. The versatile role of HuR in Glioblastoma and its potential as a therapeutic target for a multi-pronged attack. Adv Drug Deliv Rev 2022; 181:114082. [PMID: 34923029 PMCID: PMC8916685 DOI: 10.1016/j.addr.2021.114082] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 10/15/2021] [Accepted: 12/12/2021] [Indexed: 02/03/2023]
Abstract
Glioblastoma (GBM) is a malignant and aggressive brain tumor with a median survival of ∼15 months. Resistance to treatment arises from the extensive cellular and molecular heterogeneity in the three major components: glioma tumor cells, glioma stem cells, and tumor-associated microglia and macrophages. Within this triad, there is a complex network of intrinsic and secreted factors that promote classic hallmarks of cancer, including angiogenesis, resistance to cell death, proliferation, and immune evasion. A regulatory node connecting these diverse pathways is at the posttranscriptional level as mRNAs encoding many of the key drivers contain adenine- and uridine rich elements (ARE) in the 3' untranslated region. Human antigen R (HuR) binds to ARE-bearing mRNAs and is a major positive regulator at this level. This review focuses on basic concepts of ARE-mediated RNA regulation and how targeting HuR with small molecule inhibitors represents a plausible strategy for a multi-pronged therapeutic attack on GBM.
Collapse
Affiliation(s)
- Abhishek Guha
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL 35294, United States
| | - Saboora Waris
- Shaheed Zulfiqar Ali Bhutto Medical University, PIMS, G-8, Islamabad, Pakistan
| | - Louis B Nabors
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL 35294, United States
| | - Natalia Filippova
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL 35294, United States
| | - Myriam Gorospe
- Laboratory of Genetics and Genomics, National Institute on Aging Intramural Research Program, National Institutes of Health, Baltimore, MD 21224, United States
| | - Thaddaeus Kwan
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL 35294, United States
| | - Peter H King
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL 35294, United States; Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL 35294, United States; Birmingham Veterans Affairs Medical Center, Birmingham, AL 35294, United States.
| |
Collapse
|
8
|
Chellappan R, Guha A, Si Y, Kwan T, Nabors LB, Filippova N, Yang X, Myneni AS, Meesala S, Harms AS, King PH. SRI-42127, a novel small molecule inhibitor of the RNA regulator HuR, potently attenuates glial activation in a model of lipopolysaccharide-induced neuroinflammation. Glia 2022; 70:155-172. [PMID: 34533864 PMCID: PMC8595840 DOI: 10.1002/glia.24094] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 09/03/2021] [Accepted: 09/06/2021] [Indexed: 01/03/2023]
Abstract
Glial activation with the production of pro-inflammatory mediators is a major driver of disease progression in neurological processes ranging from acute traumatic injury to chronic neurodegenerative diseases such as amyotrophic lateral sclerosis and Alzheimer's disease. Posttranscriptional regulation is a major gateway for glial activation as many mRNAs encoding pro-inflammatory mediators contain adenine- and uridine-rich elements (ARE) in the 3' untranslated region which govern their expression. We have previously shown that HuR, an RNA regulator that binds to AREs, plays a major positive role in regulating inflammatory cytokine production in glia. HuR is predominantly nuclear in localization but translocates to the cytoplasm to exert a positive regulatory effect on RNA stability and translational efficiency. Homodimerization of HuR is necessary for translocation and we have developed a small molecule inhibitor, SRI-42127, that blocks this process. Here we show that SRI-42127 suppressed HuR translocation in LPS-activated glia in vitro and in vivo and significantly attenuated the production of pro-inflammatory mediators including IL1β, IL-6, TNF-α, iNOS, CXCL1, and CCL2. Cytokines typically associated with anti-inflammatory effects including TGF-β1, IL-10, YM1, and Arg1 were either unaffected or minimally affected. SRI-42127 suppressed microglial activation in vivo and attenuated the recruitment/chemotaxis of neutrophils and monocytes. RNA kinetic studies and luciferase studies indicated that SRI-42127 has inhibitory effects both on mRNA stability and gene promoter activation. In summary, our findings underscore HuR's critical role in promoting glial activation and the potential for SRI-42127 and other HuR inhibitors for treating neurological diseases driven by this activation.
Collapse
Affiliation(s)
- Rajeshwari Chellappan
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL 35294,,Birmingham Veterans Affairs Medical Center, Birmingham, AL 35294
| | - Abhishek Guha
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Ying Si
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL 35294,,Birmingham Veterans Affairs Medical Center, Birmingham, AL 35294
| | - Thaddaeus Kwan
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL 35294
| | - L. Burt Nabors
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Natalia Filippova
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Xiuhua Yang
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Anish S. Myneni
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Shriya Meesala
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Ashley S Harms
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Peter H. King
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL 35294,,Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL 35294,,Birmingham Veterans Affairs Medical Center, Birmingham, AL 35294,Correspondence to: Dr. P.H. King; UAB Dept. of Neurology, Civitan 545C, 1530 3 Avenue South, Birmingham, AL 35294-0017, USA. Tel. (205) 975-8116; Fax (205) 996-7255;
| |
Collapse
|
9
|
Kang D, Lee Y, Lee JS. RNA-Binding Proteins in Cancer: Functional and Therapeutic Perspectives. Cancers (Basel) 2020; 12:cancers12092699. [PMID: 32967226 PMCID: PMC7563379 DOI: 10.3390/cancers12092699] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 09/17/2020] [Accepted: 09/18/2020] [Indexed: 12/12/2022] Open
Abstract
Simple Summary RNA-binding proteins (RBPs) play central roles in regulating posttranscriptional expression of genes. Many of them are known to be deregulated in a wide variety of cancers. Dysregulated RBPs influence the expression levels of target RNAs related to cancer phenotypes, such as proliferation, apoptosis, angiogenesis, senescence, and EMT/invasion/metastasis. Thus, understanding the molecular functions of RBPs and their roles in cancer-related phenotypes can lead to improved therapeutic strategies. Abstract RNA-binding proteins (RBPs) crucially regulate gene expression through post-transcriptional regulation, such as by modulating microRNA (miRNA) processing and the alternative splicing, alternative polyadenylation, subcellular localization, stability, and translation of RNAs. More than 1500 RBPs have been identified to date, and many of them are known to be deregulated in cancer. Alterations in the expression and localization of RBPs can influence the expression levels of oncogenes, tumor-suppressor genes, and genome stability-related genes. RBP-mediated gene regulation can lead to diverse cancer-related cellular phenotypes, such as proliferation, apoptosis, angiogenesis, senescence, and epithelial-mesenchymal transition (EMT)/invasion/metastasis. This regulation can also be associated with cancer prognosis. Thus, RBPs can be potential targets for the development of therapeutics for the cancer treatment. In this review, we describe the molecular functions of RBPs, their roles in cancer-related cellular phenotypes, and various approaches that may be used to target RBPs for cancer treatment.
Collapse
Affiliation(s)
- Donghee Kang
- Medical Research Center, College of Medicine, Inha University, Incheon 22212, Korea; (D.K.); (Y.L.)
- Department of Molecular Medicine, College of Medicine, Inha University, Incheon 22212, Korea
- Program in Biomedical Science & Engineering, Inha University Graduate School, Incheon 22212, Korea
| | - Yerim Lee
- Medical Research Center, College of Medicine, Inha University, Incheon 22212, Korea; (D.K.); (Y.L.)
- Department of Molecular Medicine, College of Medicine, Inha University, Incheon 22212, Korea
| | - Jae-Seon Lee
- Medical Research Center, College of Medicine, Inha University, Incheon 22212, Korea; (D.K.); (Y.L.)
- Department of Molecular Medicine, College of Medicine, Inha University, Incheon 22212, Korea
- Program in Biomedical Science & Engineering, Inha University Graduate School, Incheon 22212, Korea
- Correspondence: ; Tel.: +82-32-860-9832
| |
Collapse
|
10
|
Zarnack K, Balasubramanian S, Gantier MP, Kunetsky V, Kracht M, Schmitz ML, Sträßer K. Dynamic mRNP Remodeling in Response to Internal and External Stimuli. Biomolecules 2020; 10:biom10091310. [PMID: 32932892 PMCID: PMC7565591 DOI: 10.3390/biom10091310] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 09/02/2020] [Accepted: 09/08/2020] [Indexed: 02/06/2023] Open
Abstract
Signal transduction and the regulation of gene expression are fundamental processes in every cell. RNA-binding proteins (RBPs) play a key role in the post-transcriptional modulation of gene expression in response to both internal and external stimuli. However, how signaling pathways regulate the assembly of RBPs with mRNAs remains largely unknown. Here, we summarize observations showing that the formation and composition of messenger ribonucleoprotein particles (mRNPs) is dynamically remodeled in space and time by specific signaling cascades and the resulting post-translational modifications. The integration of signaling events with gene expression is key to the rapid adaptation of cells to environmental changes and stress. Only a combined approach analyzing the signal transduction pathways and the changes in post-transcriptional gene expression they cause will unravel the mechanisms coordinating these important cellular processes.
Collapse
Affiliation(s)
- Kathi Zarnack
- Buchmann Institute for Molecular Life Sciences, Goethe University Frankfurt, 60438 Frankfurt a.M., Germany;
| | | | - Michael P. Gantier
- Centre for Innate Immunity and Infectious Diseases, Hudson Institute of Medical Research, Clayton, VIC 3168, Australia;
- Department of Molecular and Translational Science, Monash University, Clayton, VIC 3800, Australia
| | - Vladislav Kunetsky
- Institute of Biochemistry, FB08, Justus Liebig University, 35392 Giessen, Germany;
| | - Michael Kracht
- Rudolf Buchheim Institute of Pharmacology, FB11, Justus Liebig University, 35392 Giessen, Germany;
| | - M. Lienhard Schmitz
- Institute of Biochemistry, FB11, Justus Liebig University, 35392 Giessen, Germany;
| | - Katja Sträßer
- Institute of Biochemistry, FB08, Justus Liebig University, 35392 Giessen, Germany;
- Correspondence:
| |
Collapse
|
11
|
Caiazza F, Oficjalska K, Tosetto M, Phelan JJ, Noonan S, Martin P, Killick K, Breen L, O'Neill F, Nolan B, Furney S, Power R, Fennelly D, Craik CS, O'Sullivan J, Sheahan K, Doherty GA, Ryan EJ. KH-Type Splicing Regulatory Protein Controls Colorectal Cancer Cell Growth and Modulates the Tumor Microenvironment. THE AMERICAN JOURNAL OF PATHOLOGY 2019; 189:1916-1932. [PMID: 31404541 DOI: 10.1016/j.ajpath.2019.07.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 06/06/2019] [Accepted: 07/03/2019] [Indexed: 01/18/2023]
Abstract
KH-type splicing regulatory protein (KHSRP) is a multifunctional nucleic acid binding protein implicated in key aspects of cancer cell biology: inflammation and cell-fate determination. However, the role KHSRP plays in colorectal cancer (CRC) tumorigenesis remains largely unknown. Using a combination of in silico analysis of large data sets, ex vivo analysis of protein expression in patients, and mechanistic studies using in vitro models of CRC, we investigated the oncogenic role of KHSRP. We demonstrated KHSRP expression in the epithelial and stromal compartments of both primary and metastatic tumors. Elevated expression was found in tumor versus matched normal tissue, and these findings were validated in larger independent cohorts in silico. KHSRP expression was a prognostic indicator of worse overall survival (hazard ratio, 3.74; 95% CI, 1.43-22.97; P = 0.0138). Mechanistic data in CRC cell line models supported a role of KHSRP in driving epithelial cell proliferation in both a primary and metastatic setting, through control of the G1/S transition. In addition, KHSRP promoted a proangiogenic extracellular environment by regulating the secretion of oncogenic proteins involved in diverse cellular processes, such as migration and response to cellular stress. Our study provides novel mechanistic insight into the tumor-promoting effects of KHSRP in CRC.
Collapse
Affiliation(s)
- Francesco Caiazza
- Centre for Colorectal Disease, St. Vincent's University Hospital, Dublin, Ireland; Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, California.
| | - Katarzyna Oficjalska
- Centre for Colorectal Disease, St. Vincent's University Hospital, Dublin, Ireland; School of Medicine, University College Dublin, Dublin, Ireland
| | - Miriam Tosetto
- Centre for Colorectal Disease, St. Vincent's University Hospital, Dublin, Ireland
| | - James J Phelan
- Department of Surgery, Trinity Translational Medicine Institute, Trinity College Dublin, Dublin, Ireland
| | - Sinéad Noonan
- Centre for Colorectal Disease, St. Vincent's University Hospital, Dublin, Ireland
| | - Petra Martin
- Centre for Colorectal Disease, St. Vincent's University Hospital, Dublin, Ireland
| | - Kate Killick
- Systems Biology Ireland, University College Dublin, Dublin, Ireland
| | - Laura Breen
- National Institute for Cellular Biotechnology, Dublin City University, Dublin, Ireland
| | - Fiona O'Neill
- National Institute for Cellular Biotechnology, Dublin City University, Dublin, Ireland
| | - Blathnaid Nolan
- Centre for Colorectal Disease, St. Vincent's University Hospital, Dublin, Ireland
| | - Simon Furney
- Department of Physiology and Medical Physics, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Robert Power
- School of Medicine, University College Dublin, Dublin, Ireland
| | - David Fennelly
- Centre for Colorectal Disease, St. Vincent's University Hospital, Dublin, Ireland; School of Medicine, University College Dublin, Dublin, Ireland
| | - Charles S Craik
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, California
| | - Jacintha O'Sullivan
- Department of Surgery, Trinity Translational Medicine Institute, Trinity College Dublin, Dublin, Ireland
| | - Kieran Sheahan
- Centre for Colorectal Disease, St. Vincent's University Hospital, Dublin, Ireland; School of Medicine, University College Dublin, Dublin, Ireland
| | - Glen A Doherty
- Centre for Colorectal Disease, St. Vincent's University Hospital, Dublin, Ireland; School of Medicine, University College Dublin, Dublin, Ireland
| | - Elizabeth J Ryan
- Centre for Colorectal Disease, St. Vincent's University Hospital, Dublin, Ireland; School of Medicine, University College Dublin, Dublin, Ireland
| |
Collapse
|
12
|
Behrens G, Winzen R, Rehage N, Dörrie A, Barsch M, Hoffmann A, Hackermüller J, Tiedje C, Heissmeyer V, Holtmann H. A translational silencing function of MCPIP1/Regnase-1 specified by the target site context. Nucleic Acids Res 2019; 46:4256-4270. [PMID: 29471506 PMCID: PMC5934641 DOI: 10.1093/nar/gky106] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2016] [Accepted: 02/09/2018] [Indexed: 12/13/2022] Open
Abstract
The expression of proteins during inflammatory and immune reactions is coordinated by post-transcriptional mechanisms. A particularly strong suppression of protein expression is exerted by a conserved translational silencing element (TSE) identified in the 3′ UTR of NFKBIZ mRNA, which is among the targets of the RNA-binding proteins Roquin-1/2 and MCPIP1/Regnase-1. We present evidence that in the context of the TSE MCPIP1, so far known for its endonuclease activity toward mRNAs specified by distinct stem–loop (SL) structures, also suppresses translation. Overexpression of MCPIP1 silenced translation in a TSE-dependent manner and reduced ribosome occupancy of the mRNA. Correspondingly, MCPIP1 depletion alleviated silencing and increased polysomal association of the mRNA. Translationally silenced NFKBIZ or reporter mRNAs were mostly capped, polyadenylated and ribosome associated. Furthermore, MCPIP1 silenced also cap-independent, CrPV-IRES-dependent translation. This suggests that MCPIP1 suppresses a post-initiation step. The TSE is predicted to form five SL structures. SL4 and 5 resemble target structures reported for MCPIP1 and together were sufficient for MCPIP1 binding and mRNA destabilization. Translational silencing, however, required SL1–3 in addition. Thus the NFKBIZ TSE functions as an RNA element in which sequences adjacent to the site of interaction with MCPIP1 and dispensable for accelerated mRNA degradation extend the functional repertoire of MCPIP1 to translational silencing.
Collapse
Affiliation(s)
- Gesine Behrens
- Institute of Cell Biochemistry, Hannover Medical School, 30625 Hannover, Germany
| | - Reinhard Winzen
- Institute of Cell Biochemistry, Hannover Medical School, 30625 Hannover, Germany
| | - Nina Rehage
- Institute for Immunology, Biomedical Center of the Ludwig-Maximilians-Universität München, 82152 Planegg-Martinsried, Germany
| | - Anneke Dörrie
- Institute of Cell Biochemistry, Hannover Medical School, 30625 Hannover, Germany
| | - Monika Barsch
- Institute of Cell Biochemistry, Hannover Medical School, 30625 Hannover, Germany
| | - Anne Hoffmann
- Young Investigators Group Bioinformatics and Transcriptomics, Department of Molecular Systems Biology, Helmholtz Centre for Environmental Research - UFZ, 04318 Leipzig, Germany
| | - Jörg Hackermüller
- Young Investigators Group Bioinformatics and Transcriptomics, Department of Molecular Systems Biology, Helmholtz Centre for Environmental Research - UFZ, 04318 Leipzig, Germany.,Department of Computer Science, University of Leipzig, 04081 Leipzig, Germany
| | - Christopher Tiedje
- Institute of Cell Biochemistry, Hannover Medical School, 30625 Hannover, Germany
| | - Vigo Heissmeyer
- Institute for Immunology, Biomedical Center of the Ludwig-Maximilians-Universität München, 82152 Planegg-Martinsried, Germany.,Research Unit Molecular Immune Regulation, Helmholtz Zentrum München, 81377 München, Germany
| | - Helmut Holtmann
- Institute of Cell Biochemistry, Hannover Medical School, 30625 Hannover, Germany
| |
Collapse
|
13
|
Pan R, Cai W, Sun J, Yu C, Li P, Zheng M. Inhibition of KHSRP sensitizes colorectal cancer to 5-fluoruracil through miR-501-5p-mediated ERRFI1 mRNA degradation. J Cell Physiol 2019; 235:1576-1587. [PMID: 31313286 DOI: 10.1002/jcp.29076] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 06/14/2019] [Indexed: 12/23/2022]
Abstract
K-homology (KH)-type splicing regulatory protein (KHSRP) is an RNA binding protein that participates in RNA variable splicing and stability, and facilitates the biogenesis of miRNAs that target mRNA. However, to date, the role of KHSRP in colorectal cancer (CRC) progression has not been reported. In this study, the function of KHSRP in CRC proliferation and 5-fluoruracil (5-FU) resistance was investigated. The upregulation of KHSRP expression was confirmed in CRC patient tissues and two CRC cell lines. Manipulating KHSRP expression altered cell proliferation and 5-FU resistance in CRC cells. ERRFI1, a downstream effector of KHSRP in CRC cells, reduced CRC cell proliferation. Sensitivity to 5-FU mediated by KHSRP knockdown was reversed by ERRFI1 knockdown. We found that KHSRP decreased ERRFI1 mRNA expression indirectly. By screening KHSRP-regulated miRNAs, we further found that miR-501-5p directly combines with KHSRP in CRC cells. Mechanistically, the results of a luciferase assay suggested that miR-501-5p directly binds to the ERRFI1 3'-untranslated region. Taken together, our data indicated that modification of ERRFI1 by KHSRP occurs through miR-501-5p, an essential mechanism driving CRC proliferation and 5-FU resistance. Insight into this mechanism may provide novel targets for overcoming drug resistance in CRC.
Collapse
Affiliation(s)
- Ruijun Pan
- Department of General Surgery, Shanghai Minimally Invasive Surgery Center, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, P.R. China
| | - Wei Cai
- Department of General Surgery, Shanghai Minimally Invasive Surgery Center, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, P.R. China
| | - Jing Sun
- Department of General Surgery, Shanghai Minimally Invasive Surgery Center, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, P.R. China
| | - Chaoran Yu
- Department of General Surgery, Shanghai Minimally Invasive Surgery Center, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, P.R. China
| | - Peiyong Li
- Department of Nuclear Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, P.R. China
| | - Minhua Zheng
- Department of General Surgery, Shanghai Minimally Invasive Surgery Center, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, P.R. China
| |
Collapse
|
14
|
Liu W, Chou CF, Liu S, Crossman D, Yusuf N, Wu Y, Chen CY. KSRP modulates melanoma growth and efficacy of vemurafenib. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2019; 1862:759-770. [PMID: 31269460 DOI: 10.1016/j.bbagrm.2019.06.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 05/30/2019] [Accepted: 06/12/2019] [Indexed: 01/15/2023]
Abstract
The majority of melanomas carry an oncogenic BRAF mutation (BRAFV600E), which results in constitutive kinase activity driving melanoma proliferation. While inhibitors of BRAFV600E (BRAFi) effectively lead to rapid tumor shrinkage, most patients treated with BRAFi develop acquired resistance. Identification of factors as regulators of melanoma growth and as potential sources of resistance is thus crucial for the design of improved therapies to treat advanced melanoma with more durable responses. Here, we show that KH-type splicing regulatory protein (KSRP) is critical for proliferation of melanoma cells without and with acquired resistance to vemurafenib. Silencing KSRP reduces cell proliferation and augments the growth suppressive effects of vemurafenib. We identify killin (KLLN), a p53-regulated DNA replication inhibitor, as a downstream effector of growth inhibition by KSRP silencing and demonstrate that KSRP promotes decay of KLLN mRNA through an RNA-protein interaction. Using heterologous mRNA reporters, we show that a U-rich element within the 3' untranslated region of KLLN is responsible for KSRP-dependent mRNA decay. These findings implicate that KSRP is an important regulator of melanoma cell growth in part through controlling KLLN mRNA stability.
Collapse
Affiliation(s)
- Wenwen Liu
- State Key Laboratory of Structured Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, China; University of Chinese Academy of Sciences, Beijing 100049, China; Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, United States of America
| | - Chu-Fang Chou
- Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, AL 35294, United States of America
| | - Shanrun Liu
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, United States of America
| | - David Crossman
- Department of Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, United States of America
| | - Nabiha Yusuf
- Department of Dermatology, University of Alabama at Birmingham, Birmingham, AL 35294, United States of America
| | - Yunkun Wu
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, College of Life Science, Key Laboratory of OptoElectronic Science and Technology for Medicine of Ministry of Education, Fujian Normal University, Fuzhou 350119, China.
| | - Ching-Yi Chen
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, United States of America.
| |
Collapse
|
15
|
Li C, An MX, Jiang JY, Yao HB, Li S, Yan J, Li XY, Wang HQ. BAG3 Suppresses Loading of Ago2 to IL6 mRNA in Pancreatic Ductal Adenocarcinoma. Front Oncol 2019; 9:225. [PMID: 31001483 PMCID: PMC6454118 DOI: 10.3389/fonc.2019.00225] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Accepted: 03/13/2019] [Indexed: 01/16/2023] Open
Abstract
Pancreatic stellate cells (PSCs) are a subset of pancreatic cancer-associated fibroblasts, which play a critical role in pancreatic fibrosis, a characteristic feature of pancreatic cancer. The interplay between PSCs and pancreatic cancer cells is vital for promotion of tumor progression and metastasis. BAG3 is correlated with poor prognostics in patients with pancreatic ductal adenocarcinoma (PDAC), however, the exact mechanisms remain largely unknown. In this study, we demonstrated that BAG3 downregulation decreased IL6 release by PDACs, and IL6 reduction was, at least partially, responsible for suppression of PSCs activation by PDACs with BAG3 downmodulation. Importantly, BAG3 expression positively correlated with fibrosis in pancreatic cancer tissue. With regard to the underlying mechanism, we demonstrated that BAG3 knockdown facilitated recruitment of Agonaute 2 (Ago2) to IL6 mRNA, resulting in destabilization of IL6 mRNA. In addition, the current study demonstrated that phosphorylation at Serine (Ser) 387 site was required for recruitment of Ago2-containing miRISC to IL6 mRNA and BAG3 knockdown facilitated Ago2 loading to IL6 mRNA via increasing its phosphorylation at Ser 387. This study shed new light on the tumor-promoting role of BAG3 in PDAC tumors, suggesting BAG3 might represent an interesting therapeutic opportunity to PDAC patients.
Collapse
Affiliation(s)
- Chao Li
- Department of Biochemistry and Molecular Biology, China Medical University, Shenyang, China.,Key Laboratory of Cell Biology, Ministry of Public Health, and Key Laboratory of Medical Cell Biology, Ministry of Education, China Medical University, Shenyang, China
| | - Ming-Xin An
- Department of Biochemistry and Molecular Biology, China Medical University, Shenyang, China
| | - Jing-Yi Jiang
- Department of Biochemistry and Molecular Biology, China Medical University, Shenyang, China
| | - Han-Bing Yao
- Department of Biochemistry and Molecular Biology, China Medical University, Shenyang, China
| | - Si Li
- Department of Biochemistry and Molecular Biology, China Medical University, Shenyang, China
| | - Jing Yan
- Department of Biochemistry and Molecular Biology, China Medical University, Shenyang, China
| | - Xin-Yu Li
- Department of Biochemistry and Molecular Biology, China Medical University, Shenyang, China
| | - Hua-Qin Wang
- Department of Biochemistry and Molecular Biology, China Medical University, Shenyang, China.,Key Laboratory of Cell Biology, Ministry of Public Health, and Key Laboratory of Medical Cell Biology, Ministry of Education, China Medical University, Shenyang, China
| |
Collapse
|
16
|
KH-type splicing regulatory protein is regulated by nuclear factor-κB signaling to mediate innate immunity in Caco-2 cells infected by Salmonella enteritidis. Folia Microbiol (Praha) 2018; 63:669-676. [DOI: 10.1007/s12223-018-0606-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Accepted: 04/25/2018] [Indexed: 02/04/2023]
|
17
|
Li N, Cao M, Yi S, Cheng J, Wang L, Tao Y, Wu D, Peng J, Zhang M, Qi P, Zhao J. Effects of the RNA-binding protein, KSRP, on innate immune response against Helicobacter pylori infection in mice. Biochem Biophys Res Commun 2017; 495:1573-1579. [PMID: 29222050 DOI: 10.1016/j.bbrc.2017.12.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Accepted: 12/04/2017] [Indexed: 11/29/2022]
Abstract
Helicobacter pylori (H. pylori) contributes to various gastric diseases such as chronic gastritis, gastric ulcer, and gastric carcinoma. Host innate immune response against the pathogen plays a significant role in elimination of pathogen infection. Importantly, pathogen elimination is closely related to numerous inflammatory-related genes that participate in complex biological response of cells to harmful stimuli. Here we studied effects of the KH-type splicing regulatory protein (KSRP), a RNA-binding protein, on innate immune response against H. pylori infection. We found that H. pylori infection downregulated KSRP expression directly, and that KSRP overexpression repressed upregulation of CXCL-2 expression induced by H. pylori and facilitated H. pylori proliferation in vitro. Similarly, KSRP overexpression in H. pylori mice also facilitated H. pylori proliferation and colonization, and induced more severe gastric mucosal damage. Intriguingly, CXCL-2 and HMOX-1 were upregulated in H. pylori infected mice after KSRP overexpression. This difference in expression of these genes implicated that KSRP was closely associated with and directly participated in the innate immune response against H. pylori. These results were beneficial for understanding the in vivo function of KSRP on innate immune response against pathogen infection.
Collapse
Affiliation(s)
- Ningzhe Li
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065, Sichuan, PR China
| | - Mei Cao
- Core Laboratory, School of Medicine, Sichuan Provincial People's Hospital Affiliated to University of Electronic Science and Technology of China, Chengdu 610072, PR China
| | - Sijun Yi
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065, Sichuan, PR China
| | - Juan Cheng
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065, Sichuan, PR China
| | - Lei Wang
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065, Sichuan, PR China
| | - Yuwei Tao
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065, Sichuan, PR China
| | - Daoyan Wu
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065, Sichuan, PR China
| | - Jingshan Peng
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065, Sichuan, PR China
| | - Mao Zhang
- Core Laboratory, School of Medicine, Sichuan Provincial People's Hospital Affiliated to University of Electronic Science and Technology of China, Chengdu 610072, PR China
| | - Panpan Qi
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065, Sichuan, PR China
| | - Jian Zhao
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065, Sichuan, PR China.
| |
Collapse
|
18
|
Changes in haematological indices following local application of interleukin-1 receptor antagonist protein after tenotomy in rabbits. ACTA VET BRNO 2017. [DOI: 10.2754/avb201786020183] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Interleukin-1 (IL-1) is the most important cytokine in the inflammation cascade activation in all tissues and is present in acute and chronic phases of inflammation. By blocking IL-1 binding to target cells, numerous inflammation processes are prevented. The use of autologous conditioned serum rich with IL-1 receptor antagonist protein (IL-1Ra) is a novel treatment method of tendon inflammation in domestic animals and humans. Injections of autologous conditioned serum (ACS) have demonstrated clinical efficacy and safety in animal models and humans in the treatment of osteoarthritis, disc prolapse and muscles and tendons injuries with low side effect. Neutropaenia, reduced white blood cell count, and infections or local irritations are described as side effects of IL-1 antagonist use in humans. Therefore, a study of blood changes in rabbits after local administration of IL-1Ra in the Achilles tendon tissue after iatrogenic inflammation was conducted. Interleukin-1 receptor antagonist protein was used to prevent and reduce tendon inflammation after longitudinal tenotomy. The study was done on 26 white Californian rabbits, divided into two equal groups consisting of 13 animals each; the experimental interleukin-1 receptor antagonist protein (irap) group, and the control group. In the irap group, autologous serum rich with IL-1Ra was used (Orthokine®vet irap, Alfa-Arthro, Croatia). Differences between two groups were considered significant as changes in the blood for certain blood elements atP< 0.01. ThePvalue wasP= 0.0153 for the white blood cells,P= 0.00153 for neutrophils,P= 0.00017 and for platelets. In the control group, an increased platelet count was noticed in 70% of blood samples and a decreased neutrophil count was found in all of the irap group samples at the end of the study in comparison to the initial blood count prior to application.
Collapse
|
19
|
Chen CYA, Chang JT, Ho YF, Shyu AB. MiR-26 down-regulates TNF-α/NF-κB signalling and IL-6 expression by silencing HMGA1 and MALT1. Nucleic Acids Res 2016; 44:3772-87. [PMID: 27025651 PMCID: PMC4856999 DOI: 10.1093/nar/gkw205] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Accepted: 03/18/2016] [Indexed: 01/14/2023] Open
Abstract
MiR-26 has emerged as a key tumour suppressor in various cancers. Accumulating evidence supports that miR-26 regulates inflammation and tumourigenicity largely through down-regulating IL-6 production, but the underlying mechanism remains obscure. Here, combining a transcriptome-wide approach with manipulation of cellular miR-26 levels, we showed that instead of directly targeting IL-6 mRNA for gene silencing, miR-26 diminishes IL-6 transcription activated by TNF-α through silencing NF-κB signalling related factors HMGA1 and MALT1. We demonstrated that miR-26 extensively dampens the induction of many inflammation-related cytokine, chemokine and tissue-remodelling genes that are activated via NF-κB signalling pathway. Knocking down both HMGA1 and MALT1 by RNAi had a silencing effect on NF-κB-responsive genes similar to that caused by miR-26. Moreover, we discovered that poor patient prognosis in human lung adenocarcinoma is associated with low miR-26 and high HMGA1 or MALT1 levels and not with levels of any of them individually. These new findings not only unravel a novel mechanism by which miR-26 dampens IL-6 production transcriptionally but also demonstrate a direct role of miR-26 in down-regulating NF-κB signalling pathway, thereby revealing a more critical and broader role of miR-26 in inflammation and cancer than previously realized.
Collapse
Affiliation(s)
- Chyi-Ying A Chen
- Department of Biochemistry and Molecular Biology, McGovern Medical School, Houston, TX 77030, USA
| | - Jeffrey T Chang
- Department of Integrative Biology and Pharmacology, McGovern Medical School, Houston, TX 77030, USA School of Biomedical Informatics, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Yi-Fang Ho
- Department of Biochemistry and Molecular Biology, McGovern Medical School, Houston, TX 77030, USA
| | - Ann-Bin Shyu
- Department of Biochemistry and Molecular Biology, McGovern Medical School, Houston, TX 77030, USA
| |
Collapse
|
20
|
Briata P, Bordo D, Puppo M, Gorlero F, Rossi M, Perrone-Bizzozero N, Gherzi R. Diverse roles of the nucleic acid-binding protein KHSRP in cell differentiation and disease. WILEY INTERDISCIPLINARY REVIEWS-RNA 2015; 7:227-40. [PMID: 26708421 DOI: 10.1002/wrna.1327] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Revised: 11/16/2015] [Accepted: 11/17/2015] [Indexed: 12/15/2022]
Abstract
The single-stranded nucleic acid-binding protein KHSRP (KH-type splicing regulatory protein) modulates RNA life and gene expression at various levels. KHSRP controls important cellular functions as different as proliferation, differentiation, metabolism, and response to infectious agents. We summarize and discuss experimental evidence providing a potential link between changes in KHSRP expression/function and human diseases including neuromuscular disorders, obesity, type II diabetes, and cancer.
Collapse
Affiliation(s)
- Paola Briata
- Gene Expression Regulation Laboratory, IRCCS AOU San Martino-IST, Genova, Italy
| | - Domenico Bordo
- Gene Expression Regulation Laboratory, IRCCS AOU San Martino-IST, Genova, Italy
| | - Margherita Puppo
- Gene Expression Regulation Laboratory, IRCCS AOU San Martino-IST, Genova, Italy
| | - Franco Gorlero
- S.C. Ginecologia e Ostetricia Galliera Hospital, Genova, Italy.,School of Medicine, DINOGMI, University of Genova, Genova, Italy
| | - Martina Rossi
- Gene Expression Regulation Laboratory, IRCCS AOU San Martino-IST, Genova, Italy
| | - Nora Perrone-Bizzozero
- Department of Neurosciences, School of Medicine, University of New Mexico, Albuquerque, NM, USA
| | - Roberto Gherzi
- Gene Expression Regulation Laboratory, IRCCS AOU San Martino-IST, Genova, Italy
| |
Collapse
|
21
|
Response of Mammalian Macrophages to Challenge with the Chlorovirus Acanthocystis turfacea Chlorella Virus 1. J Virol 2015; 89:12096-107. [PMID: 26401040 DOI: 10.1128/jvi.01254-15] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 09/16/2015] [Indexed: 02/03/2023] Open
Abstract
UNLABELLED It was recently reported that 44% of the oropharyngeal samples from the healthy humans in a study cohort had DNA sequences similar to that of the chlorovirus ATCV-1 (Acanthocystis turfacea chlorella virus 1, family Phycodnaviridae) and that these study subjects had decreases in visual processing and visual motor speed compared with individuals in whom no virus was detected. Moreover, mice inoculated orally with ATCV-1 developed immune responses to ATCV-1 proteins and had decreases in certain cognitive domains. Because heightened interleukin-6 (IL-6), nitric oxide (NO), and ERK mitogen-activated protein (MAP) kinase activation from macrophages are linked to cognitive impairments, we evaluated cellular responses and viral PFU counts in murine RAW264.7 cells and primary macrophages after exposure to ATCV-1 in vitro for up to 72 h after a virus challenge. Approximately 8% of the ATCV-1 inoculum was associated with macrophages after 1 h, and the percentage increased 2- to 3-fold over 72 h. Immunoblot assays with rabbit anti-ATCV-1 antibody detected a 55-kDa protein consistent with the viral capsid protein from 1 to 72 h and increasing de novo synthesis of a previously unidentified 17-kDa protein beginning at 24 h. Emergence of the 17-kDa protein did not occur and persistence of the 55-kDa protein declined over time when cells were exposed to heat-inactivated ATCV-1. Moreover, starting at 24 h, RAW264.7 cells exhibited cytopathic effects, annexin V staining, and cleaved caspase 3. Activation of ERK MAP kinases occurred in these cells by 30 min postchallenge, which preceded the expression of IL-6 and NO. Therefore, ATCV-1 persistence in and induction of inflammatory factors by these macrophages may contribute to declines in the cognitive abilities of mice and humans. IMPORTANCE Virus infections that persist in and stimulate inflammatory factors in macrophages contribute to pathologies in humans. A previous study showed that DNA sequences homologous to the chlorovirus ATCV-1 were found in a significant fraction of oropharyngeal samples from a healthy human cohort. We show here that ATCV-1, whose only known host is a eukaryotic green alga (Chlorella heliozoae) that is an endosymbiont of the heliozoon Acanthocystis turfacea, can unexpectedly persist within murine macrophages and trigger inflammatory responses including factors that contribute to immunopathologies. The inflammatory factors that are produced in response to ATCV-1 include IL-6 and NO, whose induction is preceded by the activation of ERK MAP kinases. Other responses of ATCV-1-challenged macrophages include an apoptotic cytopathic effect, an innate antiviral response, and a metabolic shift toward aerobic glycolysis. Therefore, mammalian encounters with chloroviruses may contribute to chronic inflammatory responses from macrophages.
Collapse
|
22
|
Tiedje C, Holtmann H, Gaestel M. The role of mammalian MAPK signaling in regulation of cytokine mRNA stability and translation. J Interferon Cytokine Res 2015; 34:220-32. [PMID: 24697200 DOI: 10.1089/jir.2013.0146] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Extracellular-regulated kinases and p38 mitogen-activated protein kinases are activated in innate (and adaptive) immunity and signal via different routes to alter the stability and translation of various cytokine mRNAs, enabling immune cells to respond promptly. This regulation involves mRNA elements, such as AU-rich motifs, and mRNA-binding proteins, such as tristetraprolin (TTP), HuR, and hnRNPK-homology (KH) type splicing regulatory protein (KSRP). Signal-dependent phosphorylation of mRNA-binding proteins often alters their subcellular localization or RNA-binding affinity. Furthermore, it could lead to an altered interaction with other mRNA-binding proteins and altered scaffolding properties for mRNA-modifying enzymes, such as deadenylases, polyadenylases, decapping enzymes, poly(A) binding proteins, exo- or endonucleases, and proteins of the exosome machinery. In many cases, this results in unstable mRNAs being stabilized, with their translational arrest being released and cytokine production being stimulated. Hence, components of these mechanisms are potential targets for the modulation of the inflammatory response.
Collapse
Affiliation(s)
- Christopher Tiedje
- Institute of Physiological Chemistry, Hannover Medical School , Hannover, Germany
| | | | | |
Collapse
|
23
|
King PH, Chen CY. Role of KSRP in control of type I interferon and cytokine expression. J Interferon Cytokine Res 2015; 34:267-74. [PMID: 24697204 DOI: 10.1089/jir.2013.0143] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Cytokines and chemokines are key participants in pathways that drive inflammatory, immune, and other cellular responses to exogenous insults such as infection, trauma, and physiological stress. Persistent and aberrant expression of these factors has been linked to autoimmune, degenerative, and neoplastic diseases. Consequently, cytokine and chemokine expression is tightly governed at each level of gene regulation. Recent studies have demonstrated a role for KH-type splicing regulatory protein (KSRP) in curtailing cytokine and chemokine expression through transcriptional and post-transcriptional mechanisms, including promotion of microRNA maturation. Understanding the role of KSRP in cytokine mRNA metabolism should identify promising targets for the modulation of immune and inflammatory responses.
Collapse
Affiliation(s)
- Peter H King
- 1 Department of Neurology, University of Alabama at Birmingham , Birmingham, Alabama
| | | |
Collapse
|
24
|
Griseri P, Pagès G. Control of pro-angiogenic cytokine mRNA half-life in cancer: the role of AU-rich elements and associated proteins. J Interferon Cytokine Res 2015; 34:242-54. [PMID: 24697202 DOI: 10.1089/jir.2013.0140] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Control of mRNA half-life plays a central role in normal development and disease. Several pathological conditions, such as inflammation and cancer, tightly correlate with deregulation in mRNA stability of pro-inflammatory genes. Among these, pro-angiogenesis cytokines, which play a crucial role in the formation of new blood vessels, normally show rapid mRNA decay patterns. The mRNA half-life of these genes appears to be regulated by mRNA-binding proteins that interact with AU-rich elements (AREs) in the 3'-untranslated region of mRNAs. Some of these RNA-binding proteins, such as tristetraprolin (TTP), ARE RNA-binding protein 1, and KH-type splicing regulatory protein, normally promote mRNA degradation. Conversely, other proteins, such as embryonic lethal abnormal vision-like protein 1 (HuR) and polyadenylate-binding protein-interacting protein 2, act as antagonists, stabilizing the mRNA. The steady state levels of mRNA-binding proteins and their relative ratio is often perturbed in human cancers and associated with invasion and aggressiveness. Compelling evidence also suggests that underexpression of TTP and overexpression of HuR may be a useful prognostic and predictive marker in breast, colon, prostate, and brain cancers, indicating a potential therapeutic approach for these tumors. In this review, we summarize the main mechanisms involved in the regulation of mRNA decay of pro-angiogenesis cytokines in different cancers and discuss the interactions between the AU-rich-binding proteins and their mRNA targets.
Collapse
Affiliation(s)
- Paola Griseri
- 1 U.O.C Medical Genetics, Institute Giannina Gaslini , Genoa, Italy
| | | |
Collapse
|
25
|
Chou CF, Zhu X, Lin YY, Gamble KL, Garvey WT, Chen CY. KSRP is critical in governing hepatic lipid metabolism through controlling Per2 expression. J Lipid Res 2014; 56:227-40. [PMID: 25514904 DOI: 10.1194/jlr.m050724] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Hepatic lipid metabolism is controlled by integrated metabolic pathways. Excess accumulation of hepatic TG is a hallmark of nonalcoholic fatty liver disease, which is associated with obesity and insulin resistance. Here, we show that KH-type splicing regulatory protein (KSRP) ablation reduces hepatic TG levels and diet-induced hepatosteatosis. Expression of period 2 (Per2) is increased during the dark period, and circadian oscillations of several core clock genes are altered with a delayed phase in Ksrp(-/-) livers. Diurnal expression of some lipid metabolism genes is also disturbed with reduced expression of genes involved in de novo lipogenesis. Using primary hepatocytes, we demonstrate that KSRP promotes decay of Per2 mRNA through an RNA-protein interaction and show that increased Per2 expression is responsible for the phase delay in cycling of several clock genes in the absence of KSRP. Similar to Ksrp(-/-) livers, both expression of lipogenic genes and intracellular TG levels are also reduced in Ksrp(-/-) hepatocytes due to increased Per2 expression. Using heterologous mRNA reporters, we show that the AU-rich element-containing 3' untranslated region of Per2 is responsible for KSRP-dependent mRNA decay. These findings implicate that KSRP is an important regulator of circadian expression of lipid metabolism genes in the liver likely through controlling Per2 mRNA stability.
Collapse
Affiliation(s)
- Chu-Fang Chou
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Xiaolin Zhu
- Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Yi-Yu Lin
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Karen L Gamble
- Department of Psychiatry and Behavioral Neurobiology, University of Alabama at Birmingham, Birmingham, AL 35294
| | - W Timothy Garvey
- Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Ching-Yi Chen
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL 35294
| |
Collapse
|
26
|
Bollmann F, Art J, Henke J, Schrick K, Besche V, Bros M, Li H, Siuda D, Handler N, Bauer F, Erker T, Behnke F, Mönch B, Härdle L, Hoffmann M, Chen CY, Förstermann U, Dirsch VM, Werz O, Kleinert H, Pautz A. Resveratrol post-transcriptionally regulates pro-inflammatory gene expression via regulation of KSRP RNA binding activity. Nucleic Acids Res 2014; 42:12555-69. [PMID: 25352548 PMCID: PMC4227754 DOI: 10.1093/nar/gku1033] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Resveratrol shows beneficial effects in inflammation-based diseases like cancer, cardiovascular and chronic inflammatory diseases. Therefore, the molecular mechanisms of the anti-inflammatory resveratrol effects deserve more attention. In human epithelial DLD-1 and monocytic Mono Mac 6 cells resveratrol decreased the expression of iNOS, IL-8 and TNF-α by reducing mRNA stability without inhibition of the promoter activity. Shown by pharmacological and siRNA-mediated inhibition, the observed effects are SIRT1-independent. Target-fishing and drug responsive target stability experiments showed selective binding of resveratrol to the RNA-binding protein KSRP, a central post-transcriptional regulator of pro-inflammatory gene expression. Knockdown of KSRP expression prevented resveratrol-induced mRNA destabilization in human and murine cells. Resveratrol did not change KSRP expression, but immunoprecipitation experiments indicated that resveratrol reduces the p38 MAPK-related inhibitory KSRP threonine phosphorylation, without blocking p38 MAPK activation or activity. Mutation of the p38 MAPK target site in KSRP blocked the resveratrol effect on pro-inflammatory gene expression. In addition, resveratrol incubation enhanced KSRP-exosome interaction, which is important for mRNA degradation. Finally, resveratrol incubation enhanced its intra-cellular binding to the IL-8, iNOS and TNF-α mRNA. Therefore, modulation of KSRP mRNA binding activity and, thereby, enhancement of mRNA degradation seems to be the common denominator of many anti-inflammatory effects of resveratrol.
Collapse
Affiliation(s)
- Franziska Bollmann
- Department of Pharmacology, Johannes Gutenberg-University Medical Center, Mainz, Germany
| | - Julia Art
- Department of Pharmacology, Johannes Gutenberg-University Medical Center, Mainz, Germany
| | - Jenny Henke
- Department of Pharmacology, Johannes Gutenberg-University Medical Center, Mainz, Germany
| | - Katharina Schrick
- Department of Pharmacology, Johannes Gutenberg-University Medical Center, Mainz, Germany
| | - Verena Besche
- Department of Dermatology, Johannes Gutenberg-University Medical Center, Mainz, Germany Core Facility Lentiviral Transduction Service, Johannes Gutenberg-University Medical Center, Mainz, Germany
| | - Matthias Bros
- Department of Dermatology, Johannes Gutenberg-University Medical Center, Mainz, Germany Core Facility Lentiviral Transduction Service, Johannes Gutenberg-University Medical Center, Mainz, Germany
| | - Huige Li
- Department of Pharmacology, Johannes Gutenberg-University Medical Center, Mainz, Germany
| | - Daniel Siuda
- Department of Pharmacology, Johannes Gutenberg-University Medical Center, Mainz, Germany
| | - Norbert Handler
- Department of Pharmaceutical/Medicinal Chemistry, University of Vienna, Vienna, Austria
| | - Florian Bauer
- Department of Pharmaceutical/Medicinal Chemistry, University of Vienna, Vienna, Austria
| | - Thomas Erker
- Department of Pharmaceutical/Medicinal Chemistry, University of Vienna, Vienna, Austria
| | - Felix Behnke
- Chair of Pharmaceutical/Medicinal Chemistry, Institute of Pharmacy, Friedrich-Schiller-University, Jena, Germany
| | - Bettina Mönch
- pharmazentrum frankfurt/ZAFES, University Hospital, Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Lorena Härdle
- Institute of Immunology, Johannes Gutenberg-University Medical Center, Mainz, Germany
| | - Markus Hoffmann
- Department of Biochemistry & Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Ching-Yi Chen
- Department of Pharmacognosy, University of Vienna, Vienna, Austria
| | - Ulrich Förstermann
- Department of Pharmacology, Johannes Gutenberg-University Medical Center, Mainz, Germany
| | - Verena M Dirsch
- Pharmaceutical Institute, University Tuebingen, Tuebingen, Germany
| | - Oliver Werz
- pharmazentrum frankfurt/ZAFES, University Hospital, Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Hartmut Kleinert
- Department of Pharmacology, Johannes Gutenberg-University Medical Center, Mainz, Germany
| | - Andrea Pautz
- Department of Pharmacology, Johannes Gutenberg-University Medical Center, Mainz, Germany
| |
Collapse
|
27
|
Estrogen receptor, progesterone receptor, interleukin-6 and interleukin-8 are variable in breast cancer and benign stem/progenitor cell populations. BMC Cancer 2014; 14:733. [PMID: 25269750 PMCID: PMC4190475 DOI: 10.1186/1471-2407-14-733] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Accepted: 09/23/2014] [Indexed: 12/15/2022] Open
Abstract
Background Estrogen receptor positive breast cancers have high recurrence rates despite tamoxifen therapy. Breast cancer stem/progenitor cells (BCSCs) initiate tumors, but expression of estrogen (ER) or progesterone receptors (PR) and response to tamoxifen is unknown. Interleukin-6 (IL-6) and interleukin-8 (IL-8) may influence tumor response to therapy but expression in BCSCs is also unknown. Methods BCSCs were isolated from breast cancer and benign surgical specimens based on CD49f/CD24 markers. CD44 was measured. Gene and protein expression of ER alpha, ER beta, PR, IL-6 and IL-8 were measured by proximity ligation assay and qRT-PCR. Results Gene expression was highly variable between patients. On average, BCSCs expressed 10-106 fold less ERα mRNA and 10-103 fold more ERβ than tumors or benign stem/progenitor cells (SC). BCSC lin-CD49f−CD24−cells were the exception and expressed higher ERα mRNA. PR mRNA in BCSCs averaged 10-104 fold less than in tumors or benign tissue, but was similar to benign SCs. ERα and PR protein detection in BCSCs was lower than ER positive and similar to ER negative tumors. IL-8 mRNA was 10-104 higher than tumor and 102 fold higher than benign tissue. IL-6 mRNA levels were equivalent to benign and only higher than tumor in lin-CD49f−CD24−cells. IL-6 and IL-8 proteins showed overlapping levels of expressions among various tissues and cell populations. Conclusions BCSCs and SCs demonstrate patient-specific variability of gene/protein expression. BCSC gene/protein expression may vary from that of other tumor cells, suggesting a mechanism by which hormone refractory disease may occur. Electronic supplementary material The online version of this article (doi:10.1186/1471-2407-14-733) contains supplementary material, which is available to authorized users.
Collapse
|
28
|
Chou CF, Lin YY, Wang HK, Zhu X, Giovarelli M, Briata P, Gherzi R, Garvey WT, Chen CY. KSRP ablation enhances brown fat gene program in white adipose tissue through reduced miR-150 expression. Diabetes 2014; 63:2949-61. [PMID: 24722250 PMCID: PMC4141372 DOI: 10.2337/db13-1901] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Brown adipose tissue oxidizes chemical energy for heat generation and energy expenditure. Promoting brown-like transformation in white adipose tissue (WAT) is a promising strategy for combating obesity. Here, we find that targeted deletion of KH-type splicing regulatory protein (KSRP), an RNA-binding protein that regulates gene expression at multiple levels, causes a reduction in body adiposity. The expression of brown fat-selective genes is increased in subcutaneous/inguinal WAT (iWAT) of Ksrp(-/-) mice because of the elevated expression of PR domain containing 16 and peroxisome proliferator-activated receptor gamma coactivator 1α, which are key regulators promoting the brown fat gene program. The expression of microRNA (miR)-150 in iWAT is decreased due to impaired primary miR-150 processing in the absence of KSRP. We show that miR-150 directly targets and represses Prdm16 and Ppargc1a, and that forced expression of miR-150 attenuates the elevated expression of brown fat genes caused by KSRP deletion. This study reveals the in vivo function of KSRP in controlling brown-like transformation of iWAT through post-transcriptional regulation of miR-150 expression.
Collapse
Affiliation(s)
- Chu-Fang Chou
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL
| | - Yi-Yu Lin
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL
| | - Hsu-Kun Wang
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL
| | - Xiaolin Zhu
- Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, AL
| | - Matteo Giovarelli
- Gene Expression Regulation Laboratory, Istituto Nazionale per la Ricerca sul Cancro, Genova, Italy
| | - Paola Briata
- Gene Expression Regulation Laboratory, Istituto Nazionale per la Ricerca sul Cancro, Genova, Italy
| | - Roberto Gherzi
- Gene Expression Regulation Laboratory, Istituto Nazionale per la Ricerca sul Cancro, Genova, Italy
| | - W Timothy Garvey
- Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, AL
| | - Ching-Yi Chen
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL
| |
Collapse
|
29
|
miR-3940-5p associated with genetic damage in workers exposed to hexavalent chromium. Toxicol Lett 2014; 229:319-26. [DOI: 10.1016/j.toxlet.2014.06.033] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Revised: 06/21/2014] [Accepted: 06/24/2014] [Indexed: 11/19/2022]
|
30
|
Cosyn J, Christiaens V, Koningsveld V, Coucke PJ, De Coster P, De Paepe A, De Bruyn H. An Exploratory Case-Control Study on the Impact ofIL-1Gene Polymorphisms on Early Implant Failure. Clin Implant Dent Relat Res 2014; 18:234-40. [DOI: 10.1111/cid.12237] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jan Cosyn
- Department of Periodontology and Oral Implantology; Dental School; Faculty of Medicine and Health Sciences; Ghent University; Ghent Belgium
- Dental Medicine; Faculty of Medicine and Pharmacy; Free University of Brussels; Brussels Belgium
| | - Véronique Christiaens
- Department of Periodontology and Oral Implantology; Dental School; Faculty of Medicine and Health Sciences; Ghent University; Ghent Belgium
| | - Vincent Koningsveld
- Dental School; Faculty of Medicine and Health Sciences; Ghent University; Ghent Belgium
| | - Paul J. Coucke
- Center for Medical Genetics; Faculty of Medicine and Health Sciences; Ghent University; Ghent Belgium
| | - Peter De Coster
- Unit of Oral Development and Applied Oral Histology; PaeCaMed Research Group; Dental School; Faculty of Medicine and Health Sciences; Ghent University; Ghent Belgium
| | - Anne De Paepe
- Center for Medical Genetics; Faculty of Medicine and Health Sciences; Ghent University; Ghent Belgium
| | - Hugo De Bruyn
- Periodontology and Oral Implantology; Dental School; Faculty of Medicine and Health Sciences; Ghent University; Ghent Belgium
- Department of Prosthodontics; Faculty of Odontology; Malmö University; Malmö Sweden
| |
Collapse
|
31
|
Lin YY, Chou CF, Giovarelli M, Briata P, Gherzi R, Chen CY. KSRP and MicroRNA 145 are negative regulators of lipolysis in white adipose tissue. Mol Cell Biol 2014; 34:2339-49. [PMID: 24732799 PMCID: PMC4054295 DOI: 10.1128/mcb.00042-14] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Revised: 01/28/2014] [Accepted: 04/06/2014] [Indexed: 12/21/2022] Open
Abstract
White adipose tissue (WAT) releases fatty acids from stored triacylglycerol for an energy source. Here, we report that targeted deletion of KH-type splicing regulatory protein (KSRP), an RNA-binding protein that regulates gene expression at multiple levels, enhances lipolysis in epididymal WAT (eWAT) because of the upregulation of genes promoting lipolytic activity. Expression of microRNA 145 (miR-145) is decreased because of impaired primary miR-145 processing in Ksrp(-/-) eWAT. We show that miR-145 directly targets and represses Foxo1 and Cgi58, activators of lipolytic activity, and forced expression of miR-145 attenuates lipolysis. This study reveals a novel in vivo function of KSRP in controlling adipose lipolysis through posttranscriptional regulation of miR-145 expression.
Collapse
Affiliation(s)
- Yi-Yu Lin
- Department of Biochemistry & Molecular Genetics, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Chu-Fang Chou
- Department of Biochemistry & Molecular Genetics, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Matteo Giovarelli
- Gene Expression Regulation Laboratory, IRCCS AOU San Martino-IST, Genoa, Italy
| | - Paola Briata
- Gene Expression Regulation Laboratory, IRCCS AOU San Martino-IST, Genoa, Italy
| | - Roberto Gherzi
- Gene Expression Regulation Laboratory, IRCCS AOU San Martino-IST, Genoa, Italy
| | - Ching-Yi Chen
- Department of Biochemistry & Molecular Genetics, University of Alabama at Birmingham, Birmingham, Alabama, USA
| |
Collapse
|
32
|
Gherzi R, Chen CY, Ramos A, Briata P. KSRP controls pleiotropic cellular functions. Semin Cell Dev Biol 2014; 34:2-8. [PMID: 24845017 DOI: 10.1016/j.semcdb.2014.05.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Revised: 05/09/2014] [Accepted: 05/12/2014] [Indexed: 01/12/2023]
Abstract
The single-strand-RNA binding protein KSRP is able to negatively regulate gene expression operating with at least two distinct and integrated postranscriptional mechanisms: (i) by promoting decay of unstable mRNAs and (ii) by favoring maturation from precursors of select microRNAs (miRNAs) including the prototypical tumor suppressor let-7. Studies performed in primary and cultured cells as well as in mice proved that the ability of KSRP to integrate different levels of gene expression is required for proper immune response, lipid metabolism, cell-fate decisions, tissue regeneration, and DNA damage response.
Collapse
Affiliation(s)
- Roberto Gherzi
- Gene Expression Regulation Laboratory, IRCCS Azienda Ospedaliera Universitaria San Martino-IST, 16132 Genova, Italy.
| | - Ching-Yi Chen
- Department of Biochemistry & Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Andres Ramos
- Molecular Structure Division, MRC National Institute for Medical Research, The Ridgeway, Mill Hill, London NW7 1AA, UK
| | - Paola Briata
- Gene Expression Regulation Laboratory, IRCCS Azienda Ospedaliera Universitaria San Martino-IST, 16132 Genova, Italy.
| |
Collapse
|
33
|
Vindry C, Vo Ngoc L, Kruys V, Gueydan C. RNA-binding protein-mediated post-transcriptional controls of gene expression: integration of molecular mechanisms at the 3' end of mRNAs? Biochem Pharmacol 2014; 89:431-40. [PMID: 24735612 DOI: 10.1016/j.bcp.2014.04.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Revised: 04/02/2014] [Accepted: 04/03/2014] [Indexed: 01/17/2023]
Abstract
Initially identified as an occasional and peculiar mode of gene regulation in eukaryotes, RNA-binding protein-mediated post-transcriptional control of gene expression has emerged, over the last two decades, as a major contributor in the control of gene expression. A large variety of RNA-binding proteins (RBPs) allows the recognition of very diverse messenger RNA sequences and participates in the regulation of basically all cellular processes. Nevertheless, the rapid outcome of post-transcriptional regulations on the level of gene expression has favored the expansion of this type of regulation in cellular processes prone to rapid and frequent modulations such as the control of the inflammatory response. At the molecular level, the 3'untranslated region (3'UTR) of mRNA is a favored site of RBP recruitment. RBPs binding to these regions control gene expression through two major modes of regulation, namely mRNA decay and modulation of translational activity. Recent progresses suggest that these two mechanisms are often interdependent and might result one from the other. Therefore, different RBPs binding distinct RNA subsets could share similar modes of action at the molecular level. RBPs are frequent targets of post-translational modifications, thereby disclosing numerous possibilities for pharmacological interventions. However, redundancies of the transduction pathways controlling these modifications have limited the perspectives to define RBPs as new therapeutic targets. Through the analysis of several examples of RBPs binding to 3'untranslated region of mRNA, we present here recent progress and perspectives regarding this rapidly evolving field of molecular biology.
Collapse
Affiliation(s)
- Caroline Vindry
- Laboratoire de Biologie moléculaire du gène, Institut de Biologie et de Médecine Moléculaires, Université Libre de Bruxelles, 12 rue des Profs. Jeener et Brachet, Gosselies 6041, Belgium
| | - Long Vo Ngoc
- Laboratoire de Biologie moléculaire du gène, Institut de Biologie et de Médecine Moléculaires, Université Libre de Bruxelles, 12 rue des Profs. Jeener et Brachet, Gosselies 6041, Belgium
| | - Véronique Kruys
- Laboratoire de Biologie moléculaire du gène, Institut de Biologie et de Médecine Moléculaires, Université Libre de Bruxelles, 12 rue des Profs. Jeener et Brachet, Gosselies 6041, Belgium
| | - Cyril Gueydan
- Laboratoire de Biologie moléculaire du gène, Institut de Biologie et de Médecine Moléculaires, Université Libre de Bruxelles, 12 rue des Profs. Jeener et Brachet, Gosselies 6041, Belgium.
| |
Collapse
|
34
|
Rübsamen D, Kunze MM, Buderus V, Brauß TF, Bajer MM, Brüne B, Schmid T. Inflammatory conditions induce IRES-dependent translation of cyp24a1. PLoS One 2014; 9:e85314. [PMID: 24416388 PMCID: PMC3885688 DOI: 10.1371/journal.pone.0085314] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Accepted: 12/04/2013] [Indexed: 01/28/2023] Open
Abstract
Rapid alterations in protein expression are commonly regulated by adjusting translation. In addition to cap-dependent translation, which is e.g. induced by pro-proliferative signaling via the mammalian target of rapamycin (mTOR)-kinase, alternative modes of translation, such as internal ribosome entry site (IRES)-dependent translation, are often enhanced under stress conditions, even if cap-dependent translation is attenuated. Common stress stimuli comprise nutrient deprivation, hypoxia, but also inflammatory signals supplied by infiltrating immune cells. Yet, the impact of inflammatory microenvironments on translation in tumor cells still remains largely elusive. In the present study, we aimed at identifying translationally deregulated targets in tumor cells under inflammatory conditions. Using polysome profiling and microarray analysis, we identified cyp24a1 (1,25-dihydroxyvitamin D3 24-hydroxylase) to be translationally upregulated in breast tumor cells co-cultured with conditioned medium of activated monocyte-derived macrophages (CM). Using bicistronic reporter assays, we identified and validated an IRES within the 5′ untranslated region (5′UTR) of cyp24a1, which enhances translation of cyp24a1 upon CM treatment. Furthermore, IRES-dependent translation of cyp24a1 by CM was sensitive to phosphatidyl-inositol-3-kinase (PI3K) inhibition, while constitutive activation of Akt sufficed to induce its IRES activity. Our data provide evidence that cyp24a1 expression is translationally regulated via an IRES element, which is responsive to an inflammatory environment. Considering the negative feedback impact of cyp24a1 on the vitamin D responses, the identification of a novel, translational mechanism of cyp24a1 regulation might open new possibilities to overcome the current limitations of vitamin D as tumor therapeutic option.
Collapse
Affiliation(s)
- Daniela Rübsamen
- Institute of Biochemistry I, Faculty of Medicine, Goethe-University Frankfurt, Frankfurt, Germany
| | - Michael M. Kunze
- Institute of Biochemistry I, Faculty of Medicine, Goethe-University Frankfurt, Frankfurt, Germany
| | - Victoria Buderus
- Institute of Biochemistry I, Faculty of Medicine, Goethe-University Frankfurt, Frankfurt, Germany
| | - Thilo F. Brauß
- Institute of Biochemistry I, Faculty of Medicine, Goethe-University Frankfurt, Frankfurt, Germany
| | - Magdalena M. Bajer
- Institute of Biochemistry I, Faculty of Medicine, Goethe-University Frankfurt, Frankfurt, Germany
| | - Bernhard Brüne
- Institute of Biochemistry I, Faculty of Medicine, Goethe-University Frankfurt, Frankfurt, Germany
| | - Tobias Schmid
- Institute of Biochemistry I, Faculty of Medicine, Goethe-University Frankfurt, Frankfurt, Germany
- * E-mail:
| |
Collapse
|
35
|
Uehata T, Akira S. mRNA degradation by the endoribonuclease Regnase-1/ZC3H12a/MCPIP-1. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2013; 1829:708-13. [DOI: 10.1016/j.bbagrm.2013.03.001] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Revised: 03/04/2013] [Accepted: 03/04/2013] [Indexed: 01/14/2023]
|
36
|
Dhamija S, Winzen R, Doerrie A, Behrens G, Kuehne N, Schauerte C, Neumann E, Dittrich-Breiholz O, Kracht M, Holtmann H. Interleukin-17 (IL-17) and IL-1 activate translation of overlapping sets of mRNAs, including that of the negative regulator of inflammation, MCPIP1. J Biol Chem 2013; 288:19250-9. [PMID: 23658019 DOI: 10.1074/jbc.m113.452649] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Changes in gene expression during inflammation are in part caused by post-transcriptional mechanisms. A transcriptome-wide screen for changes in ribosome occupancy indicated that the inflammatory cytokine IL-17 activates translation of a group of mRNAs that overlaps partially with those affected similarly by IL-1. Included are mRNAs of IκBζ and of MCPIP1, important regulators of the quality and course of immune and inflammatory responses. Evidence for increased ribosome association of these mRNAs was also obtained in LPS-activated RAW264.7 macrophages and human peripheral blood mononuclear cells. Like IL-1, IL-17 activated translation of IκBζ mRNA by counteracting the function of a translational silencing element in its 3'-UTR defined previously. Translational silencing of MCPIP1 mRNA in unstimulated cells resulted from the combined suppressive activities of its 5'-UTR, which contains upstream open reading frames, and of its 3'-UTR, which silences independently of the 5'-UTR. Only the silencing function of the 3'-UTR was counteracted by IL-17 as well as by IL-1. Translational silencing by the 3'-UTR was dependent on a putative stem-loop-forming region previously associated with rapid degradation of the mRNA. The results suggest that translational control exerted by IL-1 and IL-17 plays an important role in the coordination of an inflammatory reaction.
Collapse
Affiliation(s)
- Sonam Dhamija
- Institute of Biochemistry, Hannover Medical School, D-30623 Hannover, Germany
| | | | | | | | | | | | | | | | | | | |
Collapse
|
37
|
An RNA element in human interleukin 6 confers escape from degradation by the gammaherpesvirus SOX protein. J Virol 2013; 87:4672-82. [PMID: 23408619 DOI: 10.1128/jvi.00159-13] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Several viruses express factors to silence host gene expression via widespread mRNA degradation. This phenotype is the result of the coordinated activity of the viral endonuclease SOX and the cellular RNA degradation enzyme Xrn1 during lytic Kaposi's sarcoma-associated herpesvirus (KSHV) infection. While most cellular transcripts are highly downregulated, a subset of host mRNA escapes turnover via unknown mechanisms. One of the most prominent escapees is the interleukin 6 (IL-6) mRNA, which accumulates robustly during KSHV lytic infection and is not subjected to SOX-induced degradation. Here we reveal that the IL-6 mRNA contains a dominant, cis-acting ∼100-nucleotide element within its 3' untranslated region (UTR) that renders it directly refractory to cleavage by SOX. This element specifically interacts with a cellular protein complex both in SOX-transfected cells and in KSHV-infected B cells. Using a directed RNA pulldown approach, we identified two components of this complex to be the AU-rich element (ARE) binding proteins AUF1 and HuR. Depletion of these proteins significantly reduced the protective capacity of the IL-6 RNA element in SOX-expressing cells. These findings suggest that SOX activity may be directly counteracted by select RNA regulatory complexes and reveal a novel mechanism contributing to the robust expression of IL-6 during KSHV replication.
Collapse
|
38
|
Enterovirus 71 infection cleaves a negative regulator for viral internal ribosomal entry site-driven translation. J Virol 2013; 87:3828-38. [PMID: 23345520 DOI: 10.1128/jvi.02278-12] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Far-upstream element-binding protein 2 (FBP2) is an internal ribosomal entry site (IRES) trans-acting factor (ITAF) that negatively regulates enterovirus 71 (EV71) translation. This study shows that EV71 infection cleaved FBP2. Live EV71 and the EV71 replicon (but not UV-inactivated virus particles) induced FBP2 cleavage, suggesting that viral replication results in FBP2 cleavage. The results also showed that virus-induced proteasome, autophagy, and caspase activity co-contribute to EV71-induced FBP2 cleavage. Using FLAG-fused FBP2, we mapped the potential cleavage fragments of FBP2 in infected cells. We also found that FBP2 altered its function when its carboxyl terminus was cleaved. This study presents a mechanism for virus-induced cellular events to cleave a negative regulator for viral IRES-driven translation.
Collapse
|
39
|
Timper K, Grisouard J, Sauter NS, Herzog-Radimerski T, Dembinski K, Peterli R, Frey DM, Zulewski H, Keller U, Müller B, Christ-Crain M. Glucose-dependent insulinotropic polypeptide induces cytokine expression, lipolysis, and insulin resistance in human adipocytes. Am J Physiol Endocrinol Metab 2013; 304:E1-13. [PMID: 23092914 DOI: 10.1152/ajpendo.00100.2012] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Obesity-related insulin resistance is linked to a chronic state of systemic and adipose tissue-derived inflammation. Glucose-dependent insulinotropic polypeptide (GIP) is an incretin hormone also acting on adipocytes. We investigated whether GIP affects inflammation, lipolysis, and insulin resistance in human adipocytes. Human subcutaneous preadipocyte-derived adipocytes, differentiated in vitro, were treated with human GIP to analyze mRNA expression and protein secretion of cytokines, glycerol, and free fatty acid release and insulin-induced glucose uptake. GIP induced mRNA expression of IL-6, IL-1β, and the IL-1 receptor antagonist IL-1Ra, whereas TNFα, IL-8, and monocyte chemotactic protein (MCP)-1 remained unchanged. Cytokine induction involved PKA and the NF-κB pathway as well as an autocrine IL-1 effect. Furthermore, GIP potentiated IL-6 and IL-1Ra secretion in the presence of LPS, IL-1β, and TNFα. GIP induced lipolysis via activation of hormone-sensitive lipase and was linked to NF-κB activation. Finally, chronic GIP treatment impaired insulin-induced glucose uptake possibly due to the observed impaired translocation of glucose transporter GLUT4. In conclusion, GIP induces an inflammatory and prolipolytic response via the PKA -NF-κB-IL-1 pathway and impairs insulin sensitivity of glucose uptake in human adipocytes.
Collapse
Affiliation(s)
- Katharina Timper
- Department of Biomedicine, University Hospital Basel, Basel, Switzerland.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
40
|
Briata P, Chen CY, Ramos A, Gherzi R. Functional and molecular insights into KSRP function in mRNA decay. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2012. [PMID: 23178464 DOI: 10.1016/j.bbagrm.2012.11.003] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
KSRP is a single strand nucleic acid binding protein that controls gene expression at multiple levels. In this review we focus on the recent molecular, cellular, and structural insights into the mRNA decay promoting function of KSRP. We discuss also some aspects of KSRP-dependent microRNA maturation from precursors that are related to its mRNA destabilizing function. This article is part of a Special Issue entitled: RNA Decay mechanisms.
Collapse
Affiliation(s)
- Paola Briata
- IRCCS Azienda Ospedaliera Universitaria San Martino, Genova, Italy
| | | | | | | |
Collapse
|
41
|
Li X, Lin WJ, Chen CY, Si Y, Zhang X, Lu L, Suswam E, Zheng L, King PH. KSRP: a checkpoint for inflammatory cytokine production in astrocytes. Glia 2012; 60:1773-84. [PMID: 22847996 DOI: 10.1002/glia.22396] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2012] [Accepted: 06/29/2012] [Indexed: 11/08/2022]
Abstract
Chronic inflammation in the central nervous system (CNS) is a central feature of many neurodegenerative and autoimmune diseases. As an immunologically competent cell, the astrocyte plays an important role in CNS inflammation. It is capable of expressing a number of cytokines such as tumor necrosis factor alpha (TNF-α) and interleukin-1 beta (IL-1β) that promote inflammation directly and through the recruitment of immune cells. Checkpoints are therefore in place to keep tight control over cytokine production. Adenylate/uridylate-rich elements (ARE) in the 3' untranslated region of cytokine mRNAs serve as a major checkpoint by regulating mRNA stability and translational efficiency. Here, we examined the impact of KH-type splicing regulatory protein (KSRP), an RNA binding protein which destabilizes mRNAs via the ARE, on cytokine expression and paracrine phenotypes of primary astrocytes. We identified a network of inflammatory mediators, including TNF-α and IL-1β, whose expression increased 2 to 4-fold at the RNA level in astrocytes isolated from KSRP(-/-) mice compared to littermate controls. Upon activation, KSRP(-/-) astrocytes produced TNF-α and IL-1β at levels that exceeded control cells by 15-fold or more. Conditioned media from KSRP(-/-) astrocytes induced chemotaxis and neuronal cell death in vitro. Surprisingly, we observed a prolongation of half-life in only a subset of mRNA targets and only after selective astrocyte activation. Luciferase reporter studies indicated that KSRP regulates cytokine gene expression at both transcriptional and post-transcriptional levels. Our results outline a critical role for KSRP in regulating pro-inflammatory mediators and have implications for a wide range of CNS inflammatory and autoimmune diseases.
Collapse
Affiliation(s)
- Xuelin Li
- Department of Neurology, University of Alabama, Birmingham, Alabama 35233-0017, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
42
|
Control of early Theiler's murine encephalomyelitis virus replication in macrophages by interleukin-6 occurs in conjunction with STAT1 activation and nitric oxide production. J Virol 2012; 86:10841-51. [PMID: 22837198 DOI: 10.1128/jvi.01402-12] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
During Theiler's murine encephalomyelitis virus (TMEV) infection of macrophages, it is thought that high interleukin-6 (IL-6) levels contribute to the demyelinating disease found in chronically infected SJL/J mice but absent in B10.S mice capable of clearing the infection. Therefore, IL-6 expression was measured in TMEV-susceptible SJL/J and TMEV-resistant B10.S macrophages during their infection with TMEV DA strain or responses to lipopolysaccharide (LPS) or poly(I · C). Unexpectedly, IL-6 production was greater in B10.S macrophages than SJL/J macrophages during the first 24 h after stimulation with TMEV, LPS, or poly(I · C). Further experiments showed that in B10.S, SJL/J, and RAW264.7 macrophage cells, IL-6 expression was dependent on extracellular signal-regulated kinase (ERK) mitogen-activated protein kinase (MAPK) and enhanced by exogenous IL-12. In SJL/J and RAW264.7 macrophages, exogenous IL-6 resulted in decreased TMEV replication, earlier activation of STAT1 and STAT3, production of nitric oxide, and earlier upregulation of several antiviral genes downstream of STAT1. However, neither inhibition of IL-6-induced nitric oxide nor knockdown of STAT1 diminished the early antiviral effect of exogenous IL-6. In addition, neutralization of endogenous IL-6 from SJL/J macrophages with Fab antibodies did not exacerbate early TMEV infection. Therefore, endogenous IL-6 expression after TMEV infection is dependent on ERK MAPK, enhanced by IL-12, but too slow to decrease viral replication during early infection. In contrast, exogenous IL-6 enhances macrophage control of TMEV infection through preemptive antiviral nitric oxide production and antiviral STAT1 activation. These results indicate that immediate-early production of IL-6 could protect macrophages from TMEV infection.
Collapse
|
43
|
Kafasla P, Karakasiliotis I, Kontoyiannis DL. Decoding the functions of post-transcriptional regulators in the determination of inflammatory states: focus on macrophage activation. WILEY INTERDISCIPLINARY REVIEWS-SYSTEMS BIOLOGY AND MEDICINE 2012; 4:509-23. [PMID: 22761012 DOI: 10.1002/wsbm.1179] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Inflammation involves a continuum of intercellular interactions and cellular responses targeting infectious or tissue damage while maintaining homeostasis. At its core, this continuum encompasses the alternating phenotypes of innate immune cells; each phenotype is typified by the expression of molecules which either support host defence or aid tissue restoration and the resolution of inflammation. The aberrant persistence of any such phenotype can drive chronic inflammatory pathology. For macrophages, these phenotypes arise as changes in cellular plasticity because of adaptation. As such their underlying gene expression programs may not be determined by robust transcriptomic and epigenetic programs but by more flexible means like post-transcriptional mechanisms affecting mRNA use. These mechanisms require the assemblies of RNA-binding proteins (RBPs) and non-coding RNAs onto specific elements on their RNA targets in Ribonucleoprotein particles (RNPs) which control mRNA maturation, turnover and translation. The collection of RNPs within a cell defines the ribonome, that is, a high order system of coordinative post-transcriptional determination. mRNAs involved in the definition of different macrophage activation phenotypes share elements of RBP recognition rendering them amenable to ribonomic regulation. The molecular features of their cognitive RBPs and the pathologies developing in the corresponding mouse mutants support their involvement in inflammatory reactions. We view this information in the context of macrophage activation states to propose that these states can be determined via differential--synergistic or antagonistic--RNP associations. In doing so, we substantiate the need for the use of systems platforms to model RNP hierarchies controlling the continuum of inflammation.
Collapse
Affiliation(s)
- Panagiota Kafasla
- Institute of Immunology, Biomedical Sciences Research Center Alexander Fleming, Vari, Greece
| | | | | |
Collapse
|
44
|
AU-rich-element-dependent translation repression requires the cooperation of tristetraprolin and RCK/P54. Mol Cell Biol 2011; 32:913-28. [PMID: 22203041 DOI: 10.1128/mcb.05340-11] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AU-rich elements (AREs), residing in the 3' untranslated region (UTR) of many labile mRNAs, are important cis-acting elements that modulate the stability of these mRNAs by collaborating with trans-acting factors such as tristetraprolin (TTP). AREs also regulate translation, but the underlying mechanism is not fully understood. Here we examined the function and mechanism of TTP in ARE-mRNA translation. Through a luciferase-based reporter system, we used knockdown, overexpression, and tethering assays in 293T cells to demonstrate that TTP represses ARE reporter mRNA translation. Polyribosome fractionation experiments showed that TTP shifts target mRNAs to lighter fractions. In murine RAW264.7 macrophages, knocking down TTP produces significantly more tumor necrosis factor alpha (TNF-α) than the control, while the corresponding mRNA level has a marginal change. Furthermore, knockdown of TTP increases the rate of biosynthesis of TNF-α, suggesting that TTP can exert effects at translational levels. Finally, we demonstrate that the general translational repressor RCK may cooperate with TTP to regulate ARE-mRNA translation. Collectively, our studies reveal a novel function of TTP in repressing ARE-mRNA translation and that RCK is a functional partner of TTP in promoting TTP-mediated translational repression.
Collapse
|