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Wu X, Zhang L, Liu C, Cheng Q, Zhao W, Chen P, Qin Y, Chen M. The NS2B-PP1α-eIF2α axis: Inhibiting stress granule formation and Boosting Zika virus replication. PLoS Pathog 2024; 20:e1012355. [PMID: 38935808 DOI: 10.1371/journal.ppat.1012355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Accepted: 06/19/2024] [Indexed: 06/29/2024] Open
Abstract
Stress granules (SGs), formed by untranslated messenger ribonucleoproteins (mRNPs) during cellular stress in eukaryotes, have been linked to flavivirus interference without clear understanding. This study reveals the role of Zika virus (ZIKV) NS2B as a scaffold protein mediating interaction between protein phosphatase 1α (PP1α) and eukaryotic initiation factor 2α (eIF2α). This interaction promotes eIF2α dephosphorylation by PP1α, inhibiting SG formation. The NS2B-PP1α complex exhibits remarkable stability, resisting ubiquitin-induced degradation and amplifying eIF2α dephosphorylation, thus promoting ZIKV replication. In contrast, the NS2BV35A mutant, interacting exclusively with eIF2α, fails to inhibit SG formation, resulting in reduced viral replication and diminished impact on brain organoid growth. These findings reveal PP1α's dual role in ZIKV infection, inducing interferon production as an antiviral factor and suppressing SG formation as a viral promoter. Moreover, we found that NS2B also serves as a versatile mechanism employed by flaviviruses to counter host antiviral defenses, primarily by broadly inhibiting SG formation. This research advances our comprehension of the complex interplay in flavivirus-host interactions, offering potential for innovative therapeutic strategies against flavivirus infections.
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Affiliation(s)
- Xiaoyan Wu
- State Key Laboratory of Virology and Modern Virology Research Center, College of Life Sciences, Wuhan University, Wuhan, China
| | - Linliang Zhang
- College of Life Sciences, Hubei University, Wuhan, China
| | - Cong Liu
- State Key Laboratory of Virology and Modern Virology Research Center, College of Life Sciences, Wuhan University, Wuhan, China
| | - Qi Cheng
- Wuhan Jinyintan Hospital, Tongji Medical College of Huazhong University of Science and Technology, Wuhan, China
| | - Wen Zhao
- Tissue Engineering and Organ Manufacturing (TEOM) lab, Department of Biomedical Engineering, Wuhan University Taikang Medical School (School of Basic Medical Sciences), Wuhan, China
| | - Pu Chen
- Tissue Engineering and Organ Manufacturing (TEOM) lab, Department of Biomedical Engineering, Wuhan University Taikang Medical School (School of Basic Medical Sciences), Wuhan, China
- Taikang Center for Life and Medical Sciences, Wuhan University, Wuhan, China
| | - Yali Qin
- State Key Laboratory of Virology and Modern Virology Research Center, College of Life Sciences, Wuhan University, Wuhan, China
- College of Life Sciences, Hubei University, Wuhan, China
| | - Mingzhou Chen
- State Key Laboratory of Virology and Modern Virology Research Center, College of Life Sciences, Wuhan University, Wuhan, China
- College of Life Sciences, Hubei University, Wuhan, China
- Taikang Center for Life and Medical Sciences, Wuhan University, Wuhan, China
- Hubei Jiangxia Laboratory, Wuhan, China
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2
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Huang B, Ren J, Ma Q, Yang F, Pan X, Zhang Y, Liu Y, Wang C, Zhang D, Wei L, Ran L, Zhao H, Liang C, Wang X, Wang S, Li H, Ning H, Ran A, Li W, Wang Y, Xiao B. A novel peptide PDHK1-241aa encoded by circPDHK1 promotes ccRCC progression via interacting with PPP1CA to inhibit AKT dephosphorylation and activate the AKT-mTOR signaling pathway. Mol Cancer 2024; 23:34. [PMID: 38360682 PMCID: PMC10870583 DOI: 10.1186/s12943-024-01940-0] [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: 10/03/2023] [Accepted: 01/12/2024] [Indexed: 02/17/2024] Open
Abstract
BACKGROUND Clear cell renal cell carcinoma (ccRCC) is the most prevalent kidney cancer with high aggressive phenotype and poor prognosis. Accumulating evidence suggests that circRNAs have been identified as pivotal mediators in cancers. However, the role of circRNAs in ccRCC progression remains elusive. METHODS The differentially expressed circRNAs in 4 paired human ccRCC and adjacent noncancerous tissues ccRCC were screened using circRNA microarrays and the candidate target was selected based on circRNA expression level using weighted gene correlation network analysis (WGCNA) and the gene expression omnibus (GEO) database. CircPDHK1 expression in ccRCC and adjacent noncancerous tissues (n = 148) were evaluated along with clinically relevant information. RT-qPCR, RNase R digestion, and actinomycin D (ActD) stability test were conducted to identify the characteristics of circPDHK1. The subcellular distribution of circPDHK1 was analyzed by subcellular fractionation assay and fluorescence in situ hybridization (FISH). Immunoprecipitation-mass spectrometry (IP-MS) and immunofluorescence (IF) were employed to evaluate the protein-coding ability of circPDHK1. ccRCC cells were transfected with siRNAs, plasmids or lentivirus approach, and cell proliferation, migration and invasion, as well as tumorigenesis and metastasis in nude mice were assessed to clarify the functional roles of circPDHK1 and its encoded peptide PDHK1-241aa. RNA-sequencing, western blot analysis, immunoprecipitation (IP) and chromatin immunoprecipitation (ChIP) assays were further employed to identify the underlying mechanisms regulated by PDHK1-241aa. RESULTS CircPDHK1 was upregulated in ccRCC tissues and closely related to WHO/ISUP stage, T stage, distant metastasis, VHL mutation and Ki-67 levels. CircPDHK1 had a functional internal ribosome entry site (IRES) and encoded a novel peptide PDHK1-241aa. Functionally, we confirmed that PDHK1-241aa and not the circPDHK1 promoted the proliferation, migration and invasion of ccRCC. Mechanistically, circPDHK1 was activated by HIF-2A at the transcriptional level. PDHK1-241aa was upregulated and interacted with PPP1CA, causing the relocation of PPP1CA to the nucleus. This thereby inhibited AKT dephosphorylation and activated the AKT-mTOR signaling pathway. CONCLUSIONS Our data indicated that circPDHK1-encoded PDHK1-241aa promotes ccRCC progression by interacting with PPP1CA to inhibit AKT dephosphorylation. This study provides novel insights into the multiplicity of circRNAs and highlights the potential use of circPDHK1 or PDHK1-241aa as a therapeutic target for ccRCC.
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Affiliation(s)
- Bo Huang
- College of Pharmacy, Chongqing Medical University, Chongqing, 400016, P.R. China
- Key Laboratory of Basic Pharmacology of Ministry of Education and Joint International Research Laboratory of Ethnomedicine of Ministry of Education, Zunyi Medical University, Zunyi, Guizhou, 563006, P.R. China
| | - Junwu Ren
- College of Pharmacy, Chongqing Medical University, Chongqing, 400016, P.R. China
| | - Qiang Ma
- College of Pharmacy, Chongqing Medical University, Chongqing, 400016, P.R. China
| | - Feifei Yang
- College of Pharmacy, Chongqing Medical University, Chongqing, 400016, P.R. China
| | - Xiaojuan Pan
- College of Pharmacy, Chongqing Medical University, Chongqing, 400016, P.R. China
| | - Yuying Zhang
- College of Pharmacy, Chongqing Medical University, Chongqing, 400016, P.R. China
| | - Yuying Liu
- College of Pharmacy, Chongqing Medical University, Chongqing, 400016, P.R. China
| | - Cong Wang
- Department of Urology, Southwest Hospital, Army Medical University, Chongqing, 400038, P.R. China
| | - Dawei Zhang
- Department of Urology, Southwest Hospital, Army Medical University, Chongqing, 400038, P.R. China
| | - Ling Wei
- Department of Urology, Southwest Hospital, Army Medical University, Chongqing, 400038, P.R. China
| | - Lingyu Ran
- Department of Kidney, Southwest Hospital, Army Medical University, Chongqing, 400038, P.R. China
| | - Hongwen Zhao
- Department of Kidney, Southwest Hospital, Army Medical University, Chongqing, 400038, P.R. China
| | - Ce Liang
- College of Pharmacy, Chongqing Medical University, Chongqing, 400016, P.R. China
| | - Xiaolin Wang
- College of Pharmacy, Chongqing Medical University, Chongqing, 400016, P.R. China
| | - Shiming Wang
- College of Pharmacy, Chongqing Medical University, Chongqing, 400016, P.R. China
| | - Haiping Li
- College of Pharmacy, Chongqing Medical University, Chongqing, 400016, P.R. China
| | - Hao Ning
- College of Pharmacy, Chongqing Medical University, Chongqing, 400016, P.R. China
| | - Ai Ran
- College of Pharmacy, Chongqing Medical University, Chongqing, 400016, P.R. China
| | - Wei Li
- Department of Pharmacy, Chongqing University Cancer Hospital, Chongqing, 400030, P.R. China.
| | - Yongquan Wang
- Department of Urology, Southwest Hospital, Army Medical University, Chongqing, 400038, P.R. China.
| | - Bin Xiao
- College of Pharmacy, Chongqing Medical University, Chongqing, 400016, P.R. China.
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3
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Wu C, Zhang W, Luo Y, Cheng C, Wang X, Jiang Y, Li S, Luo L, Yang Y. Zebrafish ppp1r21 mutant as a model for the study of primary biliary cholangitis. J Genet Genomics 2023; 50:1004-1013. [PMID: 37271428 DOI: 10.1016/j.jgg.2023.05.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 05/05/2023] [Accepted: 05/22/2023] [Indexed: 06/06/2023]
Abstract
Primary biliary cholangitis (PBC) is an autoimmune cholestatic liver disease that progresses to fibrosis and cirrhosis, resulting from the gradual destruction of intrahepatic bile ducts. Exploring genetic variants associated with PBC is essential to understand the pathogenesis of PBC. Here we identify a zebrafish balloon dog (blg) mutant with intrahepatic bile duct branching defects, exhibiting several key pathological PBC-like features, including immunodominant autoantigen PDC-E2 production, cholangiocyte apoptosis, immune cell infiltration, inflammatory activation, and liver fibrosis. blg encodes the protein phosphatase 1 regulatory subunit 21 (Ppp1r21), which is enriched in the liver and its peripheral tissues and plays a vital role in the early intrahepatic bile duct formation stage. Further studies show an excessive activation of the PI3K/AKT/mTOR pathway in the hepatic tissues in the mutant, while treatment with the pathway inhibitor LY294002 and rapamycin partially rescues intrahepatic bile duct branching defects and alleviates the PBC-like symptoms. These findings implicate the potential role of the Ppp1r21-mediated PI3K/AKT/mTOR pathway in the pathophysiology of PBC.
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Affiliation(s)
- Chaoying Wu
- Institute of Developmental Biology and Regenerative Medicine, Southwest University, Beibei, Chongqing 400715, China
| | - Wenfeng Zhang
- Institute of Developmental Biology and Regenerative Medicine, Southwest University, Beibei, Chongqing 400715, China
| | - Yiyu Luo
- Institute of Developmental Biology and Regenerative Medicine, Southwest University, Beibei, Chongqing 400715, China
| | - Chaoqing Cheng
- Institute of Developmental Biology and Regenerative Medicine, Southwest University, Beibei, Chongqing 400715, China
| | - Xinjuan Wang
- Institute of Developmental Biology and Regenerative Medicine, Southwest University, Beibei, Chongqing 400715, China
| | - Yan Jiang
- Institute of Developmental Biology and Regenerative Medicine, Southwest University, Beibei, Chongqing 400715, China
| | - Shuang Li
- Institute of Developmental Biology and Regenerative Medicine, Southwest University, Beibei, Chongqing 400715, China
| | - Lingfei Luo
- Institute of Developmental Biology and Regenerative Medicine, Southwest University, Beibei, Chongqing 400715, China
| | - Yun Yang
- Institute of Developmental Biology and Regenerative Medicine, Southwest University, Beibei, Chongqing 400715, China.
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Chu E, Mychasiuk R, Green TRF, Zamani A, Dill LK, Sharma R, Raftery AL, Tsantikos E, Hibbs ML, Semple BD. Regulation of microglial responses after pediatric traumatic brain injury: exploring the role of SHIP-1. Front Neurosci 2023; 17:1276495. [PMID: 37901420 PMCID: PMC10603304 DOI: 10.3389/fnins.2023.1276495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2023] [Accepted: 09/18/2023] [Indexed: 10/31/2023] Open
Abstract
Introduction Severe traumatic brain injury (TBI) is the world's leading cause of permanent neurological disability in children. TBI-induced neurological deficits may be driven by neuroinflammation post-injury. Abnormal activity of SH2 domain-containing inositol 5' phosphatase-1 (SHIP-1) has been associated with dysregulated immunological responses, but the role of SHIP-1 in the brain remains unclear. The current study investigated the immunoregulatory role of SHIP-1 in a mouse model of moderate-severe pediatric TBI. Methods SHIP-1+/- and SHIP-1-/- mice underwent experimental TBI or sham surgery at post-natal day 21. Brain gene expression was examined across a time course, and immunofluorescence staining was evaluated to determine cellular immune responses, alongside peripheral serum cytokine levels by immunoassays. Brain tissue volume loss was measured using volumetric analysis, and behavior changes both acutely and chronically post-injury. Results Acutely, inflammatory gene expression was elevated in the injured cortex alongside increased IBA-1 expression and altered microglial morphology; but to a similar extent in SHIP-1-/- mice and littermate SHIP-1+/- control mice. Similarly, the infiltration and activation of CD68-positive macrophages, and reactivity of GFAP-positive astrocytes, was increased after TBI but comparable between genotypes. TBI increased anxiety-like behavior acutely, whereas SHIP-1 deficiency alone reduced general locomotor activity. Chronically, at 12-weeks post-TBI, SHIP-1-/- mice exhibited reduced body weight and increased circulating cytokines. Pro-inflammatory gene expression in the injured hippocampus was also elevated in SHIP-1-/- mice; however, GFAP immunoreactivity at the injury site in TBI mice was lower. TBI induced a comparable loss of cortical and hippocampal tissue in both genotypes, while SHIP-1-/- mice showed reduced general activity and impaired working memory, independent of TBI. Conclusion Together, evidence does not support SHIP-1 as an essential regulator of brain microglial morphology, brain immune responses, or the extent of tissue damage after moderate-severe pediatric TBI in mice. However, our data suggest that reduced SHIP-1 activity induces a greater inflammatory response in the hippocampus chronically post-TBI, warranting further investigation.
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Affiliation(s)
- Erskine Chu
- Department of Neuroscience, Monash University, Melbourne, VIC, Australia
- Department of Immunology, Monash University, Melbourne, VIC, Australia
| | - Richelle Mychasiuk
- Department of Neuroscience, Monash University, Melbourne, VIC, Australia
- Deparment of Neurology, Alfred Health, Prahran, VIC, Australia
| | - Tabitha R. F. Green
- Department of Integrative Physiology, The University of Colorado Boulder, Boulder, CO, United States
| | - Akram Zamani
- Department of Neuroscience, Monash University, Melbourne, VIC, Australia
| | - Larissa K. Dill
- Department of Neuroscience, Monash University, Melbourne, VIC, Australia
- Alfred Health, Prahran, VIC, Australia
| | - Rishabh Sharma
- Department of Neuroscience, Monash University, Melbourne, VIC, Australia
| | - April L. Raftery
- Department of Immunology, Monash University, Melbourne, VIC, Australia
| | - Evelyn Tsantikos
- Department of Immunology, Monash University, Melbourne, VIC, Australia
| | - Margaret L. Hibbs
- Department of Immunology, Monash University, Melbourne, VIC, Australia
| | - Bridgette D. Semple
- Department of Neuroscience, Monash University, Melbourne, VIC, Australia
- Deparment of Neurology, Alfred Health, Prahran, VIC, Australia
- Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Parkville, VIC, Australia
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Dedigama-Arachchige PM, Acharige NPN, Zhang X, Bremer HJ, Yi Z, Pflum MKH. Identification of PP1c-PPP1R12A Substrates Using Kinase-Catalyzed Biotinylation to Identify Phosphatase Substrates. ACS OMEGA 2023; 8:35628-35637. [PMID: 37810667 PMCID: PMC10552495 DOI: 10.1021/acsomega.3c01944] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 07/21/2023] [Indexed: 10/10/2023]
Abstract
Protein phosphatase 1 regulatory subunit 12A (PPP1R12A) interacts with the catalytic subunit of protein phosphatase 1 (PP1c) to form the myosin phosphatase complex. In addition to a well-documented role in muscle contraction, the PP1c-PPP1R12A complex is associated with cytoskeleton organization, cell migration and adhesion, and insulin signaling. Despite the variety of biological functions, only a few substrates of the PP1c-PPP1R12A complex are characterized, which limit a full understanding of PP1c-PPP1R12A activities in muscle contraction and cytoskeleton regulation. Here, the chemoproteomics method Kinase-catalyzed Biotinylation to Identify Phosphatase Substrates (K-BIPS) was used to identify substrates of the PP1c-PPP1R12A complex in L6 skeletal muscle cells. K-BIPS enriched 136 candidate substrates with 14 high confidence hits. One high confidence hit, AKT1 kinase, was validated as a novel PP1c-PPP1R12A substrate. Given the previously documented role of AKT1 in PPP1R12A phosphorylation and cytoskeleton organization, the data suggest that PP1c-PPP1R12A regulates its own phosphatase activity through an AKT1-dependent feedback mechanism to influence cytoskeletal arrangement in muscle cells.
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Affiliation(s)
| | - Nuwan P N Acharige
- Department of Chemistry, Wayne State University, 5101 Cass Ave, Detroit 48202-3489, Michigan, United States
| | - Xiangmin Zhang
- Department of Pharmaceutical Sciences, Wayne State University, 259 Mack Ave, Detroit 48201, Michigan, United States
| | - Hannah J Bremer
- Department of Chemistry, Wayne State University, 5101 Cass Ave, Detroit 48202-3489, Michigan, United States
| | - Zhengping Yi
- Department of Pharmaceutical Sciences, Wayne State University, 259 Mack Ave, Detroit 48201, Michigan, United States
| | - Mary Kay H Pflum
- Department of Chemistry, Wayne State University, 5101 Cass Ave, Detroit 48202-3489, Michigan, United States
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6
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Zhang L, Jiao G, You Y, Li X, Liu J, Sun Z, Li Q, Dai Z, Ma J, Zhou H, Li G, Meng C, Chen Y. Arginine methylation of PPP1CA by CARM1 regulates glucose metabolism and affects osteogenic differentiation and osteoclastic differentiation. Clin Transl Med 2023; 13:e1369. [PMID: 37649137 PMCID: PMC10468565 DOI: 10.1002/ctm2.1369] [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: 03/13/2023] [Revised: 08/02/2023] [Accepted: 08/08/2023] [Indexed: 09/01/2023] Open
Abstract
BACKGROUND The imbalance between osteoblasts and osteoclasts may lead to osteoporosis. Osteoblasts and osteoclasts have different energy requirements, with aerobic glycolysis being the prominent metabolic feature of osteoblasts, while osteoclast differentiation and fusion are driven by oxidative phosphorylation. METHODS By polymerase chain reaction as well as Western blotting, we assayed coactivator-associated arginine methyltransferase 1 (CARM1) expression in bone tissue, the mouse precranial osteoblast cell line MC3T3-E1 and the mouse monocyte macrophage leukaemia cell line RAW264.7, and expression of related genes during osteogenic differentiation and osteoclast differentiation. Using gene overexpression (lentivirus) and loss-of-function approach (CRISPR/Cas9-mediated knockout) in vitro, we examined whether CARM1 regulates osteogenic differentiation and osteoblast differentiation by metabolic regulation. Transcriptomic assays and metabolomic assays were used to find the mechanism of action of CARM1. Furthermore, in vitro methylation assays were applied to clarify the arginine methylation site of PPP1CA by CARM1. RESULTS We discovered that CARM1 reprogrammed glucose metabolism in osteoblasts and osteoclasts from oxidative phosphorylation to aerobic glycolysis, thereby promoting osteogenic differentiation and inhibiting osteoclastic differentiation. In vivo experiments revealed that CARM1 significantly decreased bone loss in osteoporosis model mice. Mechanistically, CARM1 methylated R23 of PPP1CA, affected the dephosphorylation of AKT-T450 and AMPK-T172, and increased the activities of phosphofructokinase-1 and pructose-2,6-biphosphatase3, causing an up-regulation of glycolytic flux. At the same time, as a transcriptional coactivator, CARM1 regulated the expression of pyruvate dehydrogenase kinase 3, which resulted in the inhibition of pyruvate dehydrogenase activity and inhibition of the tricarboxylic acid cycle, leading to a subsequent decrease in the flux of oxidative phosphorylation. CONCLUSIONS These findings reveal for the first time the mechanism by which CARM1 affects both osteogenesis and osteoclast differentiation through metabolic regulation, which may represent a new feasible treatment strategy for osteoporosis.
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Affiliation(s)
- Lu Zhang
- Department of Spine SurgeryQilu Hospital of Shandong UniversityJinanShandongChina
- Department of MicroorthopaedicsAffiliated Hospital of Shandong University of Traditional Chinese MedicineJinanShandongChina
- Department of Spine SurgeryAffiliated Hospital of Jining Medical UniversityJiningShandongChina
| | - Guangjun Jiao
- Department of Spine SurgeryQilu Hospital of Shandong UniversityJinanShandongChina
| | - Yunhao You
- Department of Spine SurgeryQilu Hospital of Shandong UniversityJinanShandongChina
- Department of OrthopaedicsThe First Clinical College of Shandong UniversityJinanShandongChina
| | - Xiang Li
- Department of Spine SurgeryQilu Hospital of Shandong UniversityJinanShandongChina
- Department of OrthopaedicsThe First Clinical College of Shandong UniversityJinanShandongChina
| | - Jincheng Liu
- Department of Spine SurgeryQilu Hospital of Shandong UniversityJinanShandongChina
- Department of OrthopaedicsThe First Clinical College of Shandong UniversityJinanShandongChina
| | - Zhenqian Sun
- Department of Spine SurgeryQilu Hospital of Shandong UniversityJinanShandongChina
- Department of OrthopaedicsThe First Clinical College of Shandong UniversityJinanShandongChina
| | - Qinghui Li
- Department of Spine SurgeryQilu Hospital of Shandong UniversityJinanShandongChina
- Department of OrthopaedicsThe First Clinical College of Shandong UniversityJinanShandongChina
| | - Zihan Dai
- Department of Spine SurgeryQilu Hospital of Shandong UniversityJinanShandongChina
- Department of OrthopaedicsThe First Clinical College of Shandong UniversityJinanShandongChina
| | - Jinlong Ma
- Department of Spine SurgeryQilu Hospital of Shandong UniversityJinanShandongChina
- Department of OrthopaedicsThe First Clinical College of Shandong UniversityJinanShandongChina
| | - Hongming Zhou
- Department of Spine SurgeryShandong Provincial Hospital Affiliated to Shandong First Medical UniversityJinanShandongChina
- Department of Spine SurgeryLinyi Central HospitalLinyiShandongChina
| | - Gang Li
- Department of MicroorthopaedicsAffiliated Hospital of Shandong University of Traditional Chinese MedicineJinanShandongChina
| | - Chunyang Meng
- Department of Spine SurgeryAffiliated Hospital of Jining Medical UniversityJiningShandongChina
| | - Yunzhen Chen
- Department of Spine SurgeryQilu Hospital of Shandong UniversityJinanShandongChina
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Costa A, Cruz AC, Martins F, Rebelo S. Protein Phosphorylation Alterations in Myotonic Dystrophy Type 1: A Systematic Review. Int J Mol Sci 2023; 24:ijms24043091. [PMID: 36834509 PMCID: PMC9965115 DOI: 10.3390/ijms24043091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 01/21/2023] [Accepted: 02/01/2023] [Indexed: 02/09/2023] Open
Abstract
Among the most common muscular dystrophies in adults is Myotonic Dystrophy type 1 (DM1), an autosomal dominant disorder characterized by myotonia, muscle wasting and weakness, and multisystemic dysfunctions. This disorder is caused by an abnormal expansion of the CTG triplet at the DMPK gene that, when transcribed to expanded mRNA, can lead to RNA toxic gain of function, alternative splicing impairments, and dysfunction of different signaling pathways, many regulated by protein phosphorylation. In order to deeply characterize the protein phosphorylation alterations in DM1, a systematic review was conducted through PubMed and Web of Science databases. From a total of 962 articles screened, 41 were included for qualitative analysis, where we retrieved information about total and phosphorylated levels of protein kinases, protein phosphatases, and phosphoproteins in DM1 human samples and animal and cell models. Twenty-nine kinases, 3 phosphatases, and 17 phosphoproteins were reported altered in DM1. Signaling pathways that regulate cell functions such as glucose metabolism, cell cycle, myogenesis, and apoptosis were impaired, as seen by significant alterations to pathways such as AKT/mTOR, MEK/ERK, PKC/CUGBP1, AMPK, and others in DM1 samples. This explains the complexity of DM1 and its different manifestations and symptoms, such as increased insulin resistance and cancer risk. Further studies can be done to complement and explore in detail specific pathways and how their regulation is altered in DM1, to find what key phosphorylation alterations are responsible for these manifestations, and ultimately to find therapeutic targets for future treatments.
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8
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Xiao Y, Xiang JW, Gao Q, Bai YY, Huang ZX, Hu XH, Wang L, Li DWC. MAB21L1 promotes survival of lens epithelial cells through control of αB-crystallin and ATR/CHK1/p53 pathway. Aging (Albany NY) 2022; 14:6128-6148. [PMID: 35951367 PMCID: PMC9417230 DOI: 10.18632/aging.204203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 07/25/2022] [Indexed: 11/25/2022]
Abstract
The male abnormal gene family 21 (mab21), was initially identified in C. elegans. Since its identification, studies from different groups have shown that it regulates development of ocular tissues, brain, heart and liver. However, its functional mechanism remains largely unknown. Here, we demonstrate that Mab21L1 promotes survival of lens epithelial cells. Mechanistically, Mab21L1 upregulates expression of αB-crystallin. Moreover, our results show that αB-crystallin prevents stress-induced phosphorylation of p53 at S-20 and S-37 through abrogating the activation of the upstream kinases, ATR and CHK1. As a result of suppressing p53 activity by αB-crystallin, Mab21L1 downregulates expression of Bak but upregulates Mcl-1 during stress insult. Taken together, our results demonstrate that Mab21L1 promotes survival of lens epithelial cells through upregulation of αB-crystallin to suppress ATR/CHK1/p53 pathway.
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Affiliation(s)
- Yuan Xiao
- College of Life Sciences, Hunan Normal University, Changsha 410080, Hunan, China.,The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Tianhe, Guangzhou 510230, Guangdong, China
| | - Jia-Wen Xiang
- The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Tianhe, Guangzhou 510230, Guangdong, China
| | - Qian Gao
- College of Life Sciences, Hunan Normal University, Changsha 410080, Hunan, China.,The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Tianhe, Guangzhou 510230, Guangdong, China
| | - Yue-Yue Bai
- College of Life Sciences, Hunan Normal University, Changsha 410080, Hunan, China.,The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Tianhe, Guangzhou 510230, Guangdong, China
| | - Zhao-Xia Huang
- Department of Basic Medicine, Guizhou University of Traditional Chinese Medicine, Guiyang 121212, Guizhou, China
| | - Xiao-Hui Hu
- College of Life Sciences, Hunan Normal University, Changsha 410080, Hunan, China
| | - Ling Wang
- The Academician Work Station, Changsha Medical University, Changsha 410219, Hunan, China
| | - David Wan-Cheng Li
- College of Life Sciences, Hunan Normal University, Changsha 410080, Hunan, China.,The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Tianhe, Guangzhou 510230, Guangdong, China
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9
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Zhang L, Wang L, Hu X, Hou M, Xiao Y, Xiang J, Xie J, Chen Z, Yang T, Nie Q, Fu J, Wang Y, Zheng S, Liu Y, Gan Y, Gao Q, Bai Y, Wang J, Qi R, Zou M, Ke Q, Zhu X, Gong L, Liu Y, Li DW. MYPT1/PP1-Mediated EZH2 Dephosphorylation at S21 Promotes Epithelial-Mesenchymal Transition in Fibrosis through Control of Multiple Families of Genes. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2105539. [PMID: 35293697 PMCID: PMC9108659 DOI: 10.1002/advs.202105539] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 01/24/2022] [Indexed: 05/25/2023]
Abstract
The methyltransferase EZH2 plays an important role in regulating chromatin conformation and gene transcription. Phosphorylation of EZH2 at S21 by AKT kinase suppresses its function. However, protein phosphatases responsible for the dephosphorylation of EZH2-S21 remain elusive. Here, it is demonstrated that EZH2 is highly expressed in the ocular lens, and AKT-EZH2 axis is important in TGFβ-induced epithelial-mesenchymal transition (EMT). More importantly, it is identified that MYPT1/PP1 dephosphorylates EZH2-S21 and thus modulates its functions. MYPT1 knockout accelerates EMT, but expression of the EZH2-S21A mutant suppresses EMT through control of multiple families of genes. Furthermore, the phosphorylation status and gene expression modulation of EZH2 are implicated in control of anterior subcapsular cataracts (ASC) in human and mouse eyes. Together, the results identify the specific phosphatase for EZH2-S21 and reveal EZH2 dephosphorylation control of several families of genes implicated in lens EMT and ASC pathogenesis. These results provide important novel information in EZH2 function and regulation.
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Affiliation(s)
- Lan Zhang
- The State Key Laboratory of OphthalmologyZhongshan Ophthalmic CenterSun Yat‐sen University#54 Xianlie South RoadGuangzhouGuangdong510060China
| | - Ling Wang
- The State Key Laboratory of OphthalmologyZhongshan Ophthalmic CenterSun Yat‐sen University#54 Xianlie South RoadGuangzhouGuangdong510060China
| | - Xue‐Bin Hu
- The State Key Laboratory of OphthalmologyZhongshan Ophthalmic CenterSun Yat‐sen University#54 Xianlie South RoadGuangzhouGuangdong510060China
| | - Min Hou
- The State Key Laboratory of OphthalmologyZhongshan Ophthalmic CenterSun Yat‐sen University#54 Xianlie South RoadGuangzhouGuangdong510060China
| | - Yuan Xiao
- The State Key Laboratory of OphthalmologyZhongshan Ophthalmic CenterSun Yat‐sen University#54 Xianlie South RoadGuangzhouGuangdong510060China
| | - Jia‐Wen Xiang
- The State Key Laboratory of OphthalmologyZhongshan Ophthalmic CenterSun Yat‐sen University#54 Xianlie South RoadGuangzhouGuangdong510060China
| | - Jie Xie
- The State Key Laboratory of OphthalmologyZhongshan Ophthalmic CenterSun Yat‐sen University#54 Xianlie South RoadGuangzhouGuangdong510060China
| | - Zhi‐Gang Chen
- The State Key Laboratory of OphthalmologyZhongshan Ophthalmic CenterSun Yat‐sen University#54 Xianlie South RoadGuangzhouGuangdong510060China
| | - Tian‐Heng Yang
- The State Key Laboratory of OphthalmologyZhongshan Ophthalmic CenterSun Yat‐sen University#54 Xianlie South RoadGuangzhouGuangdong510060China
| | - Qian Nie
- The State Key Laboratory of OphthalmologyZhongshan Ophthalmic CenterSun Yat‐sen University#54 Xianlie South RoadGuangzhouGuangdong510060China
| | - Jia‐Ling Fu
- The State Key Laboratory of OphthalmologyZhongshan Ophthalmic CenterSun Yat‐sen University#54 Xianlie South RoadGuangzhouGuangdong510060China
| | - Yan Wang
- The State Key Laboratory of OphthalmologyZhongshan Ophthalmic CenterSun Yat‐sen University#54 Xianlie South RoadGuangzhouGuangdong510060China
| | - Shu‐Yu Zheng
- The State Key Laboratory of OphthalmologyZhongshan Ophthalmic CenterSun Yat‐sen University#54 Xianlie South RoadGuangzhouGuangdong510060China
| | - Yun‐Fei Liu
- The State Key Laboratory of OphthalmologyZhongshan Ophthalmic CenterSun Yat‐sen University#54 Xianlie South RoadGuangzhouGuangdong510060China
| | - Yu‐Wen Gan
- The State Key Laboratory of OphthalmologyZhongshan Ophthalmic CenterSun Yat‐sen University#54 Xianlie South RoadGuangzhouGuangdong510060China
| | - Qian Gao
- The State Key Laboratory of OphthalmologyZhongshan Ophthalmic CenterSun Yat‐sen University#54 Xianlie South RoadGuangzhouGuangdong510060China
| | - Yue‐Yue Bai
- The State Key Laboratory of OphthalmologyZhongshan Ophthalmic CenterSun Yat‐sen University#54 Xianlie South RoadGuangzhouGuangdong510060China
| | - Jing‐Miao Wang
- The State Key Laboratory of OphthalmologyZhongshan Ophthalmic CenterSun Yat‐sen University#54 Xianlie South RoadGuangzhouGuangdong510060China
| | - Rui‐Li Qi
- The State Key Laboratory of OphthalmologyZhongshan Ophthalmic CenterSun Yat‐sen University#54 Xianlie South RoadGuangzhouGuangdong510060China
| | - Ming Zou
- The State Key Laboratory of OphthalmologyZhongshan Ophthalmic CenterSun Yat‐sen University#54 Xianlie South RoadGuangzhouGuangdong510060China
| | - Qin Ke
- The State Key Laboratory of OphthalmologyZhongshan Ophthalmic CenterSun Yat‐sen University#54 Xianlie South RoadGuangzhouGuangdong510060China
| | - Xing‐Fei Zhu
- The State Key Laboratory of OphthalmologyZhongshan Ophthalmic CenterSun Yat‐sen University#54 Xianlie South RoadGuangzhouGuangdong510060China
| | - Lili Gong
- The State Key Laboratory of OphthalmologyZhongshan Ophthalmic CenterSun Yat‐sen University#54 Xianlie South RoadGuangzhouGuangdong510060China
| | - Yizhi Liu
- The State Key Laboratory of OphthalmologyZhongshan Ophthalmic CenterSun Yat‐sen University#54 Xianlie South RoadGuangzhouGuangdong510060China
| | - David Wan‐Cheng Li
- The State Key Laboratory of OphthalmologyZhongshan Ophthalmic CenterSun Yat‐sen University#54 Xianlie South RoadGuangzhouGuangdong510060China
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10
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Reinkens T, Stalke A, Huge N, Vajen B, Eilers M, Schäffer V, Dittrich-Breiholz O, Schlegelberger B, Illig T, Skawran B. Ago-RIP Sequencing Identifies New MicroRNA-449a-5p Target Genes Increasing Sorafenib Efficacy in Hepatocellular Carcinoma. J Cancer 2022; 13:62-75. [PMID: 34976171 PMCID: PMC8692677 DOI: 10.7150/jca.66016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 10/23/2021] [Indexed: 12/24/2022] Open
Abstract
BACKGROUND: Patients with hepatocellular carcinoma (HCC) have very limited treatment options. For the last fourteen years, the multi-tyrosine kinase inhibitor sorafenib has been used as standard-of-care therapeutic agent in advanced HCC. Unfortunately, drug resistance develops in many cases. Therefore, we aimed to find a way to mitigate drug resistance and to improve the sorafenib efficacy in HCC cells. MicroRNAs play a significant role in targeting genes involved in tumor control suggesting microRNA/sorafenib combination therapy as a promising treatment option in advanced HCC. METHODS: MiR-449a-5p target genes were identified by Ago-RIP sequencing and validated by luciferase reporter assays and expression analyses. Target gene expression and survival data were analyzed in public HCC datasets. Tumor-relevant functional effects of miR-449a-5p and its target genes as well as their impact on the effects of sorafenib were analyzed using in vitro assays. An indirect transwell co-culture system was used to survey anti-angiogenic effects of miR-449a-5p. RESULTS: PEA15, PPP1CA and TUFT1 were identified as direct target genes of miR-449a-5p. Overexpression of these genes correlated with a poor outcome of HCC patients. Transfection with miR-449a-5p and repression of miR-449a-5p target genes inhibited cell proliferation and angiogenesis, induced apoptosis and reduced AKT and ERK signaling in HLE and Huh7 cells. Importantly, miR-449a-5p potentiated the efficacy of sorafenib in HCC cells via downregulation of PEA15, PPP1CA and TUFT1. CONCLUSIONS: This study provides detailed insights into the targetome and regulatory network of miR-449a-5p. Our results demonstrate for the first time that targeting PEA15, PPP1CA and TUFT1 via miR-449a overexpression could have significant implications in counteracting sorafenib resistance suggesting miR-449a-5p as a promising candidate for a microRNA/sorafenib combination therapy.
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Affiliation(s)
- Thea Reinkens
- Department of Human Genetics, Hannover Medical School, Hannover, Germany
| | - Amelie Stalke
- Department of Human Genetics, Hannover Medical School, Hannover, Germany
| | - Nicole Huge
- Department of Human Genetics, Hannover Medical School, Hannover, Germany
| | - Beate Vajen
- Department of Human Genetics, Hannover Medical School, Hannover, Germany
| | - Marlies Eilers
- Department of Human Genetics, Hannover Medical School, Hannover, Germany
| | - Vera Schäffer
- Department of Human Genetics, Hannover Medical School, Hannover, Germany
| | | | | | - Thomas Illig
- Department of Human Genetics, Hannover Medical School, Hannover, Germany.,Hannover Unified Biobank (HUB), Hannover Medical School, Hannover, Germany
| | - Britta Skawran
- Department of Human Genetics, Hannover Medical School, Hannover, Germany
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11
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Kim HG, Jeong SG, Kim JH, Cho JY. Phosphatase inhibition by sodium orthovanadate displays anti-inflammatory action by suppressing AKT-IKKβ signaling in RAW264.7 cells. Toxicol Rep 2022; 9:1883-1893. [DOI: 10.1016/j.toxrep.2022.09.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Revised: 09/08/2022] [Accepted: 09/29/2022] [Indexed: 11/06/2022] Open
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12
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Chu E, Mychasiuk R, Hibbs ML, Semple BD. Dysregulated phosphoinositide 3-kinase signaling in microglia: shaping chronic neuroinflammation. J Neuroinflammation 2021; 18:276. [PMID: 34838047 PMCID: PMC8627624 DOI: 10.1186/s12974-021-02325-6] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2021] [Accepted: 11/15/2021] [Indexed: 12/15/2022] Open
Abstract
Microglia are integral mediators of innate immunity within the mammalian central nervous system. Typical microglial responses are transient, intending to restore homeostasis by orchestrating the removal of pathogens and debris and the regeneration of damaged neurons. However, prolonged and persistent microglial activation can drive chronic neuroinflammation and is associated with neurodegenerative disease. Recent evidence has revealed that abnormalities in microglial signaling pathways involving phosphatidylinositol 3-kinase (PI3K) and protein kinase B (AKT) may contribute to altered microglial activity and exacerbated neuroimmune responses. In this scoping review, the known and suspected roles of PI3K-AKT signaling in microglia, both during health and pathological states, will be examined, and the key microglial receptors that induce PI3K-AKT signaling in microglia will be described. Since aberrant signaling is correlated with neurodegenerative disease onset, the relationship between maladapted PI3K-AKT signaling and the development of neurodegenerative disease will also be explored. Finally, studies in which microglial PI3K-AKT signaling has been modulated will be highlighted, as this may prove to be a promising therapeutic approach for the future treatment of a range of neuroinflammatory conditions.
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Affiliation(s)
- Erskine Chu
- Department of Immunology and Pathology, Central Clinical School, Monash University, Level 6, 89 Commercial Road, Melbourne, VIC, 3004, Australia
- Department of Neuroscience, Central Clinical School, Monash University, Level 6, 99 Commercial Road, Melbourne, VIC, 3004, Australia
| | - Richelle Mychasiuk
- Department of Neuroscience, Central Clinical School, Monash University, Level 6, 99 Commercial Road, Melbourne, VIC, 3004, Australia
- Department of Neurology, Alfred Health, Prahran, VIC, 3181, Australia
| | - Margaret L Hibbs
- Department of Immunology and Pathology, Central Clinical School, Monash University, Level 6, 89 Commercial Road, Melbourne, VIC, 3004, Australia.
| | - Bridgette D Semple
- Department of Neuroscience, Central Clinical School, Monash University, Level 6, 99 Commercial Road, Melbourne, VIC, 3004, Australia.
- Department of Neurology, Alfred Health, Prahran, VIC, 3181, Australia.
- Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Parkville, VIC, 3050, Australia.
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13
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Wang L, Zhang L, Gong X, Fu J, Gan Y, Hou M, Nie Q, Xiang J, Xiao Y, Wang Y, Zheng S, Yang L, Chen H, Xiang M, Liu Y, Li DW. PP-1β and PP-2Aα modulate cAMP response element-binding protein (CREB) functions in aging control and stress response through de-regulation of αB-crystallin gene and p300-p53 signaling axis. Aging Cell 2021; 20:e13458. [PMID: 34425033 PMCID: PMC8441381 DOI: 10.1111/acel.13458] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Revised: 07/04/2021] [Accepted: 08/06/2021] [Indexed: 02/06/2023] Open
Abstract
The function of the transcription factor, cAMP response element‐binding protein (CREB), is activated through S133 phosphorylation by PKA and others. Regarding its inactivation, it is not well defined. cAMP response element‐binding protein plays an essential role in promoting cell proliferation, neuronal survival and the synaptic plasticity associated with long‐term memory. Our recent studies have shown that CREB is an important player in mediating stress response. Here, we have demonstrated that CREB regulates aging process through suppression of αB‐crystallin and activation of the p300‐p53‐Bak/Bax signaling axis. First, we determined that two specific protein phosphatases, PP‐1β and PP‐2Aα, can inactivate CREB through S133 dephosphorylation. Subsequently, we demonstrated that cells expressing the S133A‐CREB, a mutant mimicking constant dephosphorylation at S133, suppress CREB functions in aging control and stress response. Mechanistically, S133A‐CREB not only significantly suppresses CREB control of αB‐crystallin gene, but also represses CREB‐mediated activation of p53 acetylation and downstream Bak/Bax genes. cAMP response element‐binding protein suppression of αB‐crystallin and its activation of p53 acetylation are major molecular events observed in human cataractous lenses of different age groups. Together, our results demonstrate that PP‐1β and PP‐2Aα modulate CREB functions in aging control and stress response through de‐regulation of αB‐crystallin gene and p300‐p53‐Bax/Bak signaling axis, which regulates human cataractogenesis in the aging lens.
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Affiliation(s)
- Ling Wang
- The State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat‐sen University Guangzhou China
| | - Lan Zhang
- The State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat‐sen University Guangzhou China
| | - Xiao‐Dong Gong
- The State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat‐sen University Guangzhou China
| | - Jia‐Ling Fu
- The State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat‐sen University Guangzhou China
| | - Yu‐Wen Gan
- The State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat‐sen University Guangzhou China
| | - Min Hou
- The State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat‐sen University Guangzhou China
| | - Qian Nie
- The State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat‐sen University Guangzhou China
| | - Jia‐Wen Xiang
- The State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat‐sen University Guangzhou China
| | - Yuan Xiao
- The State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat‐sen University Guangzhou China
| | - Yan Wang
- The State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat‐sen University Guangzhou China
| | - Shu‐Yu Zheng
- The State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat‐sen University Guangzhou China
| | - Lan Yang
- The State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat‐sen University Guangzhou China
| | - Huimin Chen
- The State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat‐sen University Guangzhou China
| | - Meng‐Qing Xiang
- The State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat‐sen University Guangzhou China
| | - Yizhi Liu
- The State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat‐sen University Guangzhou China
| | - David Wan‐Cheng Li
- The State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat‐sen University Guangzhou China
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14
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Matos B, Howl J, Jerónimo C, Fardilha M. Modulation of serine/threonine-protein phosphatase 1 (PP1) complexes: A promising approach in cancer treatment. Drug Discov Today 2021; 26:2680-2698. [PMID: 34390863 DOI: 10.1016/j.drudis.2021.08.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 04/23/2021] [Accepted: 08/05/2021] [Indexed: 01/21/2023]
Abstract
Cancer is the second leading cause of death worldwide. Despite the availability of numerous therapeutic options, tumor heterogeneity and chemoresistance have limited the success of these treatments, and the development of effective anticancer therapies remains a major focus in oncology research. The serine/threonine-protein phosphatase 1 (PP1) and its complexes have been recognized as potential drug targets. Research on the modulation of PP1 complexes is currently at an early stage, but has immense potential. Chemically diverse compounds have been developed to disrupt or stabilize different PP1 complexes in various cancer types, with the objective of inhibiting disease progression. Beneficial results obtained in vitro now require further pre-clinical and clinical validation. In conclusion, the modulation of PP1 complexes seems to be a promising, albeit challenging, therapeutic strategy for cancer.
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Affiliation(s)
- Bárbara Matos
- Laboratory of Signal Transduction, Department of Medical Sciences, Institute of Biomedicine-iBiMED, University of Aveiro, 3810-193 Aveiro, Portugal; Cancer Biology and Epigenetics Group, IPO Porto Research Center (CI-IPOP), Portuguese Institute of Oncology of Porto (IPO Porto), 4200-072 Porto, Portugal
| | - John Howl
- Molecular Pharmacology Group, Research Institute in Healthcare Science, University of Wolverhampton, Wolverhampton WV1 1LY, UK
| | - Carmen Jerónimo
- Cancer Biology and Epigenetics Group, IPO Porto Research Center (CI-IPOP), Portuguese Institute of Oncology of Porto (IPO Porto), 4200-072 Porto, Portugal; Department of Pathology and Molecular Immunology, Institute of Biomedical Sciences Abel Salazar, University of Porto (ICBAS-UP), 4050-513 Porto, Portugal
| | - Margarida Fardilha
- Laboratory of Signal Transduction, Department of Medical Sciences, Institute of Biomedicine-iBiMED, University of Aveiro, 3810-193 Aveiro, Portugal.
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15
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Nie Q, Chen H, Zou M, Wang L, Hou M, Xiang JW, Luo Z, Gong XD, Fu JL, Wang Y, Zheng SY, Xiao Y, Gan YW, Gao Q, Bai YY, Wang JM, Zhang L, Tang XC, Hu X, Gong L, Liu Y, Li DWC. The E3 Ligase PIAS1 Regulates p53 Sumoylation to Control Stress-Induced Apoptosis of Lens Epithelial Cells Through the Proapoptotic Regulator Bax. Front Cell Dev Biol 2021; 9:660494. [PMID: 34195189 PMCID: PMC8237824 DOI: 10.3389/fcell.2021.660494] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 04/20/2021] [Indexed: 01/31/2023] Open
Abstract
Protein sumoylation is one of the most important post-translational modifications regulating many biological processes (Flotho A & Melchior F. 2013. Ann Rev. Biochem. 82:357–85). Our previous studies have shown that sumoylation plays a fundamental role in regulating lens differentiation (Yan et al., 2010. PNAS, 107(49):21034-9.; Gong et al., 2014. PNAS. 111(15):5574–9). Whether sumoylation is implicated in lens pathogenesis remains elusive. Here, we present evidence to show that the protein inhibitor of activated STAT-1 (PIAS1), a E3 ligase for sumoylation, is implicated in regulating stress-induced lens pathogenesis. During oxidative stress-induced cataractogenesis, expression of PIAS1 is significantly altered at both mRNA and protein levels. Upregulation and overexpression of exogenous PIAS1 significantly enhances stress-induced apoptosis. In contrast, silence of PIAS1 with CRISPR/Cas9 technology attenuates stress-induced apoptosis. Mechanistically, different from other cells, PIAS1 has little effect to activate JNK but upregulates Bax, a major proapoptotic regulator. Moreover, Bax upregulation is derived from the enhanced transcription activity of the upstream transcription factor, p53. As revealed previously in other cells by different laboratories, our data also demonstrate that PIAS1 promotes SUMO1 conjugation of p53 at K386 residue in lens epithelial cells and thus enhances p53 transcription activity to promote Bax upregulation. Silence of Bax expression largely abrogates PIAS1-mediated enhancement of stress-induced apoptosis. Thus, our results demonstrated that PIAS1 promotes oxidative stress-induced apoptosis through positive control of p53, which specifically upregulates expression of the downstream proapoptotic regulator Bax. As a result, PIAS1-promoted apoptosis induced by oxidative stress is implicated in lens pathogenesis.
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Affiliation(s)
- Qian Nie
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Huimin Chen
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Ming Zou
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Ling Wang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Min Hou
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Jia-Wen Xiang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Zhongwen Luo
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Xiao-Dong Gong
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Jia-Ling Fu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Yan Wang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Shu-Yu Zheng
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Yuan Xiao
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Yu-Wen Gan
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Qian Gao
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Yue-Yue Bai
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Jing-Miao Wang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Lan Zhang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Xiang-Cheng Tang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Xuebin Hu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Lili Gong
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Yizhi Liu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - David Wan-Cheng Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
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16
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Oncogenic SNORD12B activates the AKT-mTOR-4EBP1 signaling in esophageal squamous cell carcinoma via nucleus partitioning of PP-1α. Oncogene 2021; 40:3734-3747. [PMID: 33941854 DOI: 10.1038/s41388-021-01809-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 04/06/2021] [Accepted: 04/20/2021] [Indexed: 02/03/2023]
Abstract
Esophageal cancer is a complex malignancy and the sixth leading cause of cancer death worldwide. In Eastern Asia including China, about 90% of all incident cases have esophageal squamous cell carcinoma (ESCC). Mounting evidence elucidates that aberrant expression of various non-coding RNAs (ncRNAs) contributes to ESCC progression, but it remains unclear how small nucleolar RNAs (snoRNAs) are involved in ESCC development. We systemically screened clinically relevant snoRNAs in ESCC via integrative analyses of The Cancer Genome Atlas (TCGA) data and validation in ESCC tissues. We found that snoRNA SNORD12B was one of the most evidently upregulated snoRNAs in ESCC specimens and its high expression was significantly associated with poor prognosis of patients. SNORD12B profoundly promoted proliferation, migration, invasion, and metastasis of ESCC cells in vitro and in vivo, indicating its oncogene nature. In particular, SNORD12B could interact with PP-1α, one of the three catalytic subunits of serine/threonine protein phosphatase 1, which is a major phosphatase that directly dephosphorylates AKT to suppress its activation. Interestingly, high levels of SNORD12B in ESCC cells could break interactions between 14-3-3ζ and PP-1α, abolish the retention of PP-1α in the cytosol by 14-3-3ζ and relocate PP-1α from the cytosol to the nucleus. This led to sequestered PP-1α in the nucleus, enhanced phosphorylation of AKT in the cytosol, activated AKT-mTOR-4EBP1 signaling, and, thus, ESCC progression. These insights would improve our understanding of how snoRNAs contribute to tumorigenesis and highlight the potential of snoRNAs as future therapeutic targets against cancers.
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17
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Dong W, Rasid O, Chevalier C, Connor M, Eldridge MJG, Hamon MA. Streptococcus pneumoniae Infection Promotes Histone H3 Dephosphorylation by Modulating Host PP1 Phosphatase. Cell Rep 2021; 30:4016-4026.e4. [PMID: 32209465 DOI: 10.1016/j.celrep.2020.02.116] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 01/15/2020] [Accepted: 02/21/2020] [Indexed: 10/24/2022] Open
Abstract
Pathogenic bacteria can alter host gene expression through post-translational modifications of histones. We show that a natural colonizer, Streptococcus pneumoniae, induces specific histone modifications, including robust dephosphorylation of histone H3 on serine 10 (H3S10), during infection of respiratory epithelial cells. The bacterial pore-forming toxin pneumolysin (PLY), along with the pyruvate oxidase SpxB responsible for H2O2 production, play important roles in the induction of this modification. The combined effects of PLY and H2O2 trigger host signaling that culminates in H3S10 dephosphorylation, which is mediated by the host cell phosphatase PP1. Strikingly, S. pneumoniae infection induces dephosphorylation and subsequent activation of PP1 catalytic activity. Colonization of PP1 catalytically deficient cells results in impaired intracellular S. pneumoniae survival and infection. Interestingly, PP1 activation and H3S10 dephosphorylation are not restricted to S. pneumoniae and appear to be general epigenomic mechanisms favoring intracellular survival of pathogenic bacteria.
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Affiliation(s)
- Wenyang Dong
- G5 Chromatine et Infection, Institut Pasteur, Paris 75015, France; Université de Paris, Sorbonne Paris Cité, Paris, France
| | - Orhan Rasid
- G5 Chromatine et Infection, Institut Pasteur, Paris 75015, France
| | | | - Michael Connor
- G5 Chromatine et Infection, Institut Pasteur, Paris 75015, France
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18
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Gaviraghi M, Rabellino A, Andolfo A, Brand M, Brombin C, Bagnato P, De Feudis G, Raimondi A, Locatelli A, Tosoni D, Mazza D, Gianni L, Tonon G, Yarden Y, Tacchetti C, Daniele T. Direct stimulation of ERBB2 highlights a novel cytostatic signaling pathway driven by the receptor Thr 701 phosphorylation. Sci Rep 2020; 10:16906. [PMID: 33037285 PMCID: PMC7547737 DOI: 10.1038/s41598-020-73835-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Accepted: 09/16/2020] [Indexed: 11/19/2022] Open
Abstract
ERBB2 is a ligand-less tyrosine kinase receptor expressed at very low levels in normal tissues; when overexpressed, it is involved in malignant transformation and tumorigenesis in several carcinomas. In cancer cells, ERBB2 represents the preferred partner of other members of the ERBB receptor family, leading to stronger oncogenic signals, by promoting both ERK and AKT activation. The identification of the specific signaling downstream of ERBB2 has been impaired by the lack of a ligand and of an efficient way to selectively activate the receptor. In this paper, we found that antibodies (Abs) targeting different epitopes on the ERBB2 extracellular domain foster the activation of ERBB2 homodimers, and surprisingly induce a unique cytostatic signaling cascade promoting an ERK-dependent ERBB2 Thr701 phosphorylation, leading to AKT de-phosphorylation, via PP2A Ser/Thr phosphatases. Furthermore, the immunophilin Cyclophilin A plays a crucial role in this pathway, acting as a negative modulator of AKT de-phosphorylation, possibly by competing with Ser/Thr phosphatases for binding to AKT. Altogether, our data show that Ab recognizing ERBB2 extracellular domain function as receptor agonists, promoting ERBB2 homodimer activation, leading to an anti-proliferative signaling. Thus, the ultimate outcome of ERBB2 activity might depend on the dimerization status: pro-oncogenic in the hetero-, and anti-oncogenic in the homo-dimeric form.
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Affiliation(s)
- Marco Gaviraghi
- Division of Experimental Oncology, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific Institute, via Olgettina 60, 20132, Milan, Italy
| | - Andrea Rabellino
- Department of Experimental Medicine, University of Genoa, via De Toni 14, 16132, Genoa, Italy.,QIMR Berghofer Medical Research Institute, Brisbane, QLD, 4029, Australia
| | - Annapaola Andolfo
- Protein Microsequencing Facility, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific Institute, via Olgettina 60, 20132, Milan, Italy
| | - Matthias Brand
- Experimental Imaging Centre, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific Institute, via Olgettina 58, 20132, Milan, Italy.,CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, 1090, Vienna, Austria
| | - Chiara Brombin
- University Centre for Statistics in the Biomedical Sciences, Vita-Salute San Raffaele University, via Olgettina 58, 20132, Milan, Italy
| | - Paola Bagnato
- Department of Experimental Medicine, University of Genoa, via De Toni 14, 16132, Genoa, Italy
| | - Giuseppina De Feudis
- Experimental Imaging Centre, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific Institute, via Olgettina 58, 20132, Milan, Italy
| | - Andrea Raimondi
- Experimental Imaging Centre, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific Institute, via Olgettina 58, 20132, Milan, Italy
| | - Alberta Locatelli
- Department of Oncology, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific Institute, via Olgettina 60, 20132, Milan, Italy
| | - Daniela Tosoni
- Department of Experimental Oncology, IEO, European Institute of Oncology IRCCS, 20100, Milan, Italy
| | - Davide Mazza
- Experimental Imaging Centre, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific Institute, via Olgettina 58, 20132, Milan, Italy
| | - Luca Gianni
- Department of Oncology, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific Institute, via Olgettina 60, 20132, Milan, Italy
| | - Giovanni Tonon
- Division of Experimental Oncology, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific Institute, via Olgettina 60, 20132, Milan, Italy.,Center for Translational Genomics and Bioinformatics, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific Institute, via Olgettina 60, 20132, Milan, Italy
| | - Yosef Yarden
- Weizmann Institute of Science, 76100, Rehovot, Israel
| | - Carlo Tacchetti
- Experimental Imaging Centre, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific Institute, via Olgettina 58, 20132, Milan, Italy. .,Vita-Salute San Raffaele University, via Olgettina 58, 20132, Milan, Italy.
| | - Tiziana Daniele
- Department of Experimental Medicine, University of Genoa, via De Toni 14, 16132, Genoa, Italy. .,Experimental Imaging Centre, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific Institute, via Olgettina 58, 20132, Milan, Italy.
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Soares ATG, da Silva AC, Tinkov AA, Khan H, Santamaría A, Skalnaya MG, Skalny AV, Tsatsakis A, Bowman AB, Aschner M, Ávila DS. The impact of manganese on neurotransmitter systems. J Trace Elem Med Biol 2020; 61:126554. [PMID: 32480053 PMCID: PMC7677177 DOI: 10.1016/j.jtemb.2020.126554] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Revised: 04/09/2020] [Accepted: 05/15/2020] [Indexed: 02/07/2023]
Abstract
BACKGROUND Manganese (Mn) is a metal ubiquitously present in nature and essential for many living organisms. As a trace element, it is required in small amounts for the proper functioning of several important enzymes, and reports of Mn deficiency are indeed rare. METHODS This mini-review will cover aspects of Mn toxicokinetics and its impact on brain neurotransmission, as well as its Janus-faced effects on humans and other animal's health. RESULTS The estimated safe upper limit of intracellular Mn for physiological function is in anarrow range of 20-53 μM.Therefore, intake of higher levels of Mn and the outcomes, especially to the nervous system, have been well documented. CONCLUSION The metal affects mostly the brain by accumulating in specific areas, altering cognitive functions and locomotion, thus severely impacting the health of the exposed organisms.
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Affiliation(s)
- Ana Thalita Gonçalves Soares
- Laboratory of Biochemistry and Toxicology in Caenorhabditis elegans, Graduation Program in Biochemistry, Federal University of Pampa Campus Uruguaiana, RS, Brazil
| | - Aline Castro da Silva
- Laboratory of Biochemistry and Toxicology in Caenorhabditis elegans, Graduation Program in Biochemistry, Federal University of Pampa Campus Uruguaiana, RS, Brazil
| | - Alexey A. Tinkov
- Yaroslavl State University, Yaroslavl, Russia
- IM Sechenov First Moscow State Medical University, Moscow, Russia
- Federal Scientific Center of Biological Systems and Agrotechnologies of the Russian Academy of Sciences, 460000, Orenburg, Russia
| | - Haroon Khan
- Department of pharmacy, Abdul Wali khan University Mardan 23200, Pakistan
| | - Abel Santamaría
- Laboratorio de Aminoácidos Excitadores, Instituto Nacional de Neurología y Neurocirugía, SSA. Mexico City, Mexico
| | | | - Anatoly V. Skalny
- IM Sechenov First Moscow State Medical University, Moscow, Russia
- Federal Scientific Center of Biological Systems and Agrotechnologies of the Russian Academy of Sciences, 460000, Orenburg, Russia
| | - Aristidis Tsatsakis
- Laboratory of Toxicology, Medical School, School of Medicine, University of Crete, Heraklion 71003, Greece
| | - Aaron B. Bowman
- School of Health Sciences, Purdue University, West Lafayette, IN 47906, USA
| | - Michael Aschner
- IM Sechenov First Moscow State Medical University, Moscow, Russia
- Department of Molecular Pharmacology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA
| | - Daiana Silva Ávila
- Laboratory of Biochemistry and Toxicology in Caenorhabditis elegans, Graduation Program in Biochemistry, Federal University of Pampa Campus Uruguaiana, RS, Brazil
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20
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Figueroa VA, Jara O, Oliva CA, Ezquer M, Ezquer F, Retamal MA, Martínez AD, Altenberg GA, Vargas AA. Contribution of Connexin Hemichannels to the Decreases in Cell Viability Induced by Linoleic Acid in the Human Lens Epithelial Cells (HLE-B3). Front Physiol 2020; 10:1574. [PMID: 32038277 PMCID: PMC6984129 DOI: 10.3389/fphys.2019.01574] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Accepted: 12/16/2019] [Indexed: 01/16/2023] Open
Abstract
Connexin (Cx) proteins form gap junction channels (GJC) and hemichannels that a allow bidirectional flow of ions and metabolites between the cytoplasm and extracellular space, respectively. Under physiological conditions, hemichannels have a very low probability of opening, but in certain pathologies, hemichannels activity can increase and induce and/or accelerate cell death. Several mechanisms control hemichannels activity, including phosphorylation and oxidation (i.e., S-nitrosylation). Recently, the effect of polyunsaturated fatty acids (PUFAs) such as linoleic acid (LA), were found to modulate Cxs. It has been seen that LA increase cell death in bovine and human lens cells. The lens is a structure allocated in the eye that highly depends on Cx for the metabolic coupling between its cells, a condition necessary for its transparency. Therefore, we hypothesized that LA induces lens cells death by modulating hemichannel activity. In this work, we characterized the effect of LA on hemichannel activity and survival of HLE-B3 cells (a human lens epithelial cell line). We found that HLE-B3 cells expresses Cx43, Cx46, and Cx50 and can form functional hemichannels in their plasma membrane. The extracellular exposure to 10–50 μM of LA increases hemichannels activity (dye uptake) in a concentration-dependent manner, which was reduced by Cx-channel blockers, such as the Cx-mimetic peptide Gap27 and TATGap19, La3+, carbenoxolone (CBX) and the Akt kinase inhibitor. Additionally, LA increases intracellular calcium, which is attenuated in the presence of TATGap19, a specific Cx43-hemichannel inhibitor. Finally, the long exposure of HLE-B3 cells to LA 20 and 50 μM, reduced cell viability, which was prevented by CBX. Moreover, LA increased the proportion of apoptotic HLE-B3 cells, effect that was prevented by the Cx-mimetic peptide TAT-Gap19 but not by Akt inhibitor. Altogether, these findings strongly suggest a contribution of hemichannels opening in the cell death induced by LA in HLE-B3 cells. These cells can be an excellent tool to develop pharmacological studies in vitro.
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Affiliation(s)
- Vania A Figueroa
- Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Santiago, Chile.,Instituto de Ciencias de la Salud, Universidad de O'Higgins, Rancagua, Chile
| | - Oscar Jara
- Department of Pediatrics, University of Chicago, Chicago, IL, United States
| | - Carolina A Oliva
- Centro de Envejecimiento y Regeneración (CARE-UC), Departamento Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Marcelo Ezquer
- Centro de Medicina Regenerativa, Facultad de Medicina, Clínica Alemana Universidad del Desarrollo, Santiago, Chile
| | - Fernando Ezquer
- Centro de Medicina Regenerativa, Facultad de Medicina, Clínica Alemana Universidad del Desarrollo, Santiago, Chile
| | - Mauricio A Retamal
- Universidad del Desarrollo, Centro de Fisiología Celular e Integrativa, Facultad de Medicina Clínica Alemana, Santiago, Chile.,Department of Cell Physiology and Molecular Biophysics, Texas Tech University Health Sciences Center, Lubbock, TX, United States.,Center for Membrane Protein Research, Texas Tech University Health Sciences Center, Lubbock, TX, United States
| | - Agustín D Martínez
- Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Guillermo A Altenberg
- Department of Cell Physiology and Molecular Biophysics, Texas Tech University Health Sciences Center, Lubbock, TX, United States.,Center for Membrane Protein Research, Texas Tech University Health Sciences Center, Lubbock, TX, United States
| | - Aníbal A Vargas
- Instituto de Ciencias de la Salud, Universidad de O'Higgins, Rancagua, Chile.,Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
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21
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Tang X, Chen Z, Deng M, Wang L, Nie Q, Xiang JW, Xiao Y, Yang L, Liu Y, Li DWC. The Sumoylation Modulated Tumor Suppressor p53 Regulates Cell Cycle Checking Genes to Mediate Lens Differentiation. Curr Mol Med 2019; 18:556-565. [PMID: 30636605 DOI: 10.2174/1566524019666190111154450] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 12/25/2018] [Accepted: 01/07/2019] [Indexed: 12/12/2022]
Abstract
PURPOSE The tumor suppressor p53 is a master regulator of apoptosis and also plays a key role in cell cycle checking. In our previous studies, we demonstrated that p53 directly regulates Bak in mouse JB6 cells and that p53-Bak signaling axis plays an important role in mediating EGCG-induced apoptosis. Furthermore, we have recently demonstrated that the same p53-Bak apoptotic signaling axis executes an essential role in regulating lens cell differentiation. In addition, we have also shown that p53 controls both transcription factors, C-Maf and Prox-1 as well as lens crystallin genes, αA, β- and γ-crystallins. Here, we have examined whether p53 also regulates other known target genes during its modulation of lens differentiation. The human and mouse lens epithelial cells, FHL124 and αTN4-1 were cultured in Dulbecco's modified Eagle's medium (DMEM) containing 10% fetal bovine serum (FBS) and 1% Penicillin-Streptomycin. METHODS Mice used in this study were handled in compliance with the "Protocol for the Care and Use of Laboratory Animals" (Sun Yat-sen University). Adult mice were used for the collection of lens cells. These samples were used for extraction of total proteins. A total of 32 embryonic mice {8 at 14.5 ED, 8 at 17.5 ED and 8 newborns for wild type} were used for immunohistochemistry, which were used for co-localization study. The mRNA levels were analysed with qRT-PCR. The protein levels were determined with western blot analysis and quantitated with Image J. RESULTS Immunohistochemistry revealed that both the cell cycle checking genes, p21 and Gadd45α and the apoptotic genes, Bcl-2 and PUMA, display developmental changes associated with p53 during mouse lens development. Knockdown of p53 in the mouse lens epithelial cells caused inhibition of lens differentiation. Associated with this inhibition, the cell cycle genes displayed significant downreglation, the apoptotic genes was also attenuated but to a much less degree. In addition, we found that bFGF can induce dose-dependent upregulation of the upstream kinases, CHK1/2 and ERK1/2, both known to phosphorylate p53 and activate the later. Furthermore, We showed that in both developing lens and human lens epithelial cells, p53 can be co-localized with the catalytic subunit of the protein phoshphatase-1 (PP-1), suggesting that PP-1 regulates p53 phosphorylation status both in vivo and in vitro. CONCLUSION Taken together, our results suggest that during mouse lens development, p53 activity is regulated by ERK and CHK kinases-mediated activation, and by PP-1-mediated inactivation. p53 can regulate multiple groups of genes to mediate lens differentiation.
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Affiliation(s)
- Xiangcheng Tang
- The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, #7 Jinsui Road, Guangzhou, Guangdong 510230, China
| | - Zhigang Chen
- The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, #7 Jinsui Road, Guangzhou, Guangdong 510230, China
| | - Mi Deng
- The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, #7 Jinsui Road, Guangzhou, Guangdong 510230, China
| | - Ling Wang
- The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, #7 Jinsui Road, Guangzhou, Guangdong 510230, China
| | - Qian Nie
- The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, #7 Jinsui Road, Guangzhou, Guangdong 510230, China
| | - Jia-Wen Xiang
- The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, #7 Jinsui Road, Guangzhou, Guangdong 510230, China
| | - Yuan Xiao
- The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, #7 Jinsui Road, Guangzhou, Guangdong 510230, China
| | - Lan Yang
- The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, #7 Jinsui Road, Guangzhou, Guangdong 510230, China
| | - Yizhi Liu
- The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, #7 Jinsui Road, Guangzhou, Guangdong 510230, China
| | - David Wan-Cheng Li
- The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, #7 Jinsui Road, Guangzhou, Guangdong 510230, China
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22
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Pascale RM, Simile MM, Peitta G, Seddaiu MA, Feo F, Calvisi DF. Experimental Models to Define the Genetic Predisposition to Liver Cancer. Cancers (Basel) 2019; 11:cancers11101450. [PMID: 31569678 PMCID: PMC6826893 DOI: 10.3390/cancers11101450] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 08/24/2019] [Accepted: 09/23/2019] [Indexed: 12/14/2022] Open
Abstract
Hepatocellular carcinoma (HCC) is a frequent human cancer and the most frequent liver tumor. The study of genetic mechanisms of the inherited predisposition to HCC, implicating gene-gene and gene-environment interaction, led to the discovery of multiple gene loci regulating the growth and multiplicity of liver preneoplastic and neoplastic lesions, thus uncovering the action of multiple genes and epistatic interactions in the regulation of the individual susceptibility to HCC. The comparative evaluation of the molecular pathways involved in HCC development in mouse and rat strains differently predisposed to HCC indicates that the genes responsible for HCC susceptibility control the amplification and/or overexpression of c-Myc, the expression of cell cycle regulatory genes, and the activity of Ras/Erk, AKT/mTOR, and of the pro-apoptotic Rassf1A/Nore1A and Dab2IP/Ask1 pathways, the methionine cycle, and DNA repair pathways in mice and rats. Comparative functional genetic studies, in rats and mice differently susceptible to HCC, showed that preneoplastic and neoplastic lesions of resistant mouse and rat strains cluster with human HCC with better prognosis, while the lesions of susceptible mouse and rats cluster with HCC with poorer prognosis, confirming the validity of the studies on the influence of the genetic predisposition to hepatocarinogenesis on HCC prognosis in mouse and rat models. Recently, the hydrodynamic gene transfection in mice provided new opportunities for the recognition of genes implicated in the molecular mechanisms involved in HCC pathogenesis and prognosis. This method appears to be highly promising to further study the genetic background of the predisposition to this cancer.
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Affiliation(s)
- Rosa M Pascale
- Department of Medical, Surgical and Experimental Sciences, Via P. Manzella 4, 07100 Sassari, Italy.
| | - Maria M Simile
- Department of Medical, Surgical and Experimental Sciences, Via P. Manzella 4, 07100 Sassari, Italy.
| | - Graziella Peitta
- Department of Medical, Surgical and Experimental Sciences, Via P. Manzella 4, 07100 Sassari, Italy.
| | - Maria A Seddaiu
- Department of Medical, Surgical and Experimental Sciences, Via P. Manzella 4, 07100 Sassari, Italy.
| | - Francesco Feo
- Department of Medical, Surgical and Experimental Sciences, Via P. Manzella 4, 07100 Sassari, Italy.
| | - Diego F Calvisi
- Department of Medical, Surgical and Experimental Sciences, Via P. Manzella 4, 07100 Sassari, Italy.
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23
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Li J, An R, Lai S, Li L, Liu S, Xu H. Dysregulation of PP2A-Akt interaction contributes to Sucrose non-fermenting related kinase (SNRK) deficiency induced insulin resistance in adipose tissue. Mol Metab 2019; 28:26-35. [PMID: 31420304 PMCID: PMC6822176 DOI: 10.1016/j.molmet.2019.07.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2019] [Revised: 07/23/2019] [Accepted: 07/30/2019] [Indexed: 12/16/2022] Open
Abstract
Objective We previously identified Sucrose non-fermenting related kinase (SNRK) as a regulator of adipose inflammation and energy homeostasis. In this study, we aimed to investigate the role of SNRK in insulin signaling in white (WAT) and brown adipose tissue (BAT). Methods Adipose tissue specific (SNRK deficiency in both WAT and BAT) and BAT specific knockout mouse models were employed. Phosphoproteomic studies were conducted to identify the novel SNRK pathway regulating insulin signaling in adipose tissue. Results SNRK ablation is sufficient to inhibit insulin-stimulated AKT phosphorylation and glucose uptake in both WAT and BAT. Phosphoproteomic study using SNRK deficient versus wild type BAT samples revealed 99% reduction of phosphorylation on Serine 80 of PPP2R5D, the regulatory subunit of Protein phosphatase 2A (PP2A). Drastic (142.5-fold) induction of phosphorylation on Serine 80 of PPP2R5D was observed in SNRK-deficient primary brown adipocytes overexpressing SNRK compared to control protein. In vitro phosphorylation reaction followed by targeted phosphoproteomic detection further confirms that human recombinant SNRK is able to phosphorylate human recombinant PPP2R5D. Dephosphorylated PPP2R5D promotes constitutive assembly of PP2A-AKT complex, therefore inhibits insulin-induced AKT phosphorylation and subsequent glucose uptake in both BAT and WAT. Knockdown of PPP2R5D in adipocytes can improve insulin sensitivity in adipocytes without SNRK expression. Conclusions Our findings demonstrate that SNRK regulates insulin signaling through controlling PPP2R5D phosphorylation, which subsequently impacts PP2A activity and then AKT phosphorylation in both WAT and BAT. SNRK may represent a promising potential target for treating insulin resistance-related metabolic disorders. SNRK is essential for insulin-stimulated AKT phosphorylation in adipose tissue. SNRK ablation causes insulin resistance in both white and brown adipose tissue. Phosphoproteomic studies identify PPP2R5D as a novel substrate of SNRK. SNRK regulates PP2A-AKT interaction through PPP2R5D phosphorylation. Enhanced PP2A activity by SNRK ablation inhibits AKT phosphorylation.
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Affiliation(s)
- Jie Li
- Department of Epidemiology, Brown University, Providence, RI, USA; Center for Global Cardiometabolic Health, Brown University, Providence, RI, USA; National Key Discipline, Department of Nutrition and Food Hygiene, School of Public Health, Harbin Medical University, Harbin, China
| | - Ran An
- Department of Epidemiology, Brown University, Providence, RI, USA; Center for Global Cardiometabolic Health, Brown University, Providence, RI, USA; Department of Pharmaceutical Analysis and Analytical Chemistry, College of Pharmacy, Harbin Medical University, Harbin, China
| | - Shuiqing Lai
- Department of Endocrinology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China; Department of Epidemiology, Brown University, Providence, RI, USA; Center for Global Cardiometabolic Health, Brown University, Providence, RI, USA
| | - Linlin Li
- Department of Epidemiology, Brown University, Providence, RI, USA; Center for Global Cardiometabolic Health, Brown University, Providence, RI, USA; Department of Epidemiology & Biostatistics, School of Public Health, Zhengzhou University, China
| | - Simin Liu
- Department of Epidemiology, Brown University, Providence, RI, USA; Center for Global Cardiometabolic Health, Brown University, Providence, RI, USA
| | - Haiyan Xu
- Department of Epidemiology, Brown University, Providence, RI, USA; Center for Global Cardiometabolic Health, Brown University, Providence, RI, USA.
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24
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Kumar M, John M, Madhavan M, James J, Omkumar RV. Alteration in the phosphorylation status of NMDA receptor GluN2B subunit by activation of both NMDA receptor and L-type voltage gated calcium channel. Neurosci Lett 2019; 709:134343. [PMID: 31279915 DOI: 10.1016/j.neulet.2019.134343] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 06/03/2019] [Accepted: 06/18/2019] [Indexed: 01/27/2023]
Abstract
Calcium influx through N-methyl-D-aspartate receptors (NMDAR) and voltage-gated calcium channels (VGCC) play major roles in postsynaptic signaling mechanisms. NMDAR subunit GluN2B is phosphorylated at Ser1303. Phosphorylation at this site is a prominent event in cell culture systems as well as in vivo. However, the functional significance of phosphorylation at this site is not completely understood. In this study, we compared the effect of calcium signaling through NMDAR and VGCC on the phosphorylation status of GluN2B-Ser1303 in the rat in vivo. VGCC was activated by intraperitoneal (IP) injection of the activator, BayK8644 and NMDAR was activated by intracerebroventricular (ICV) injection of NMDA in separate experimental groups. We found that the level of phospho-GluN2B-Ser1303 in the cortex and in the hippocampus increased in response to activation of either channel. The effects could be prevented by prior ICV administration of the specific blockers of these channels such as MK-801 for NMDAR and nifedipine for VGCC. The effect was also blocked by pretreatment with ICV administration of KN-93 indicating that it is mediated through CaM kinase. Both during NMDAR activation and VGCC activation, cell survival associated signals such as phospho-AKT and phospho-CREB showed decrease, consistent with activation of cell death pathways during these treatments. We conclude that under in vivo conditions, calcium influx through either NMDAR or VGCC activates CaM kinase, which in turn phosphorylates GluN2B-Ser1303.
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Affiliation(s)
- Mantosh Kumar
- Molecular Neurobiology Division, Rajiv Gandhi Centre for Biotechnology, Thycaud, P.O., Thiruvananthapuram-695014, Kerala, India; Research Scholar, University of Kerala, India
| | - Mathew John
- Molecular Neurobiology Division, Rajiv Gandhi Centre for Biotechnology, Thycaud, P.O., Thiruvananthapuram-695014, Kerala, India
| | - Mayadevi Madhavan
- Molecular Neurobiology Division, Rajiv Gandhi Centre for Biotechnology, Thycaud, P.O., Thiruvananthapuram-695014, Kerala, India
| | - Jackson James
- Neuro Stem Cell Biology Lab, Rajiv Gandhi Centre for Biotechnology, India
| | - Ramakrishnapillai V Omkumar
- Molecular Neurobiology Division, Rajiv Gandhi Centre for Biotechnology, Thycaud, P.O., Thiruvananthapuram-695014, Kerala, India.
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25
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Inhibition of protein phosphatase 1 stimulates noncanonical ER stress eIF2α activation to enhance fisetin-induced chemosensitivity in HDAC inhibitor-resistant hepatocellular carcinoma cells. Cancers (Basel) 2019; 11:cancers11070918. [PMID: 31261976 PMCID: PMC6678694 DOI: 10.3390/cancers11070918] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Revised: 06/14/2019] [Accepted: 06/28/2019] [Indexed: 02/06/2023] Open
Abstract
Hepatocellular carcinoma (HCC) is a common fatal type of malignant tumor that has highly metastatic and recurrent properties. Fisetin is a natural flavonoid found in various vegetables and fruits which exhibits anti-cancer and anti-inflammatory properties, as well as other effects. Thus, we hypothesized that fisetin can act as an adjuvant therapy in cancer or drug-resistant cancer cells, and further investigated the molecular mechanisms underlying the development of drug-resistance in HCC cells. We found that fisetin effectively inhibited the cell viability of not only parental cells but also histone deacetylase inhibitors-resistant (HDACis-R) cells and enhanced the chemosensitivity of HCC cells. Interestingly, fisetin did not induce cell apoptosis through the activation of the endoplasmic reticulum (ER) stress sensor of protein kinase R (PKR)-like endoplasmic reticulum kinase, but rather through the non-canonical pathway of the protein phosphatase 1 (PP1)-mediated suppression of eIF2α phosphorylation. Moreover, fisetin-induced cell apoptosis was reversed by treatment with PP1 activator or eIF2α siRNA in HCC cells. Based on these observations, we suggest that PP1-eIF2α pathways are significantly involved in the effect of fisetin on HCC apoptosis. Thus, fisetin may act as a novel anticancer drug and new chemotherapy adjuvant which can improve the efficacy of chemotherapeutic agents and diminish their side-effects.
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Sakaguchi M, Cai W, Wang CH, Cederquist CT, Damasio M, Homan EP, Batista T, Ramirez AK, Gupta MK, Steger M, Wewer Albrechtsen NJ, Singh SK, Araki E, Mann M, Enerbäck S, Kahn CR. FoxK1 and FoxK2 in insulin regulation of cellular and mitochondrial metabolism. Nat Commun 2019; 10:1582. [PMID: 30952843 PMCID: PMC6450906 DOI: 10.1038/s41467-019-09418-0] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Accepted: 02/26/2019] [Indexed: 01/07/2023] Open
Abstract
A major target of insulin signaling is the FoxO family of Forkhead transcription factors, which translocate from the nucleus to the cytoplasm following insulin-stimulated phosphorylation. Here we show that the Forkhead transcription factors FoxK1 and FoxK2 are also downstream targets of insulin action, but that following insulin stimulation, they translocate from the cytoplasm to nucleus, reciprocal to the translocation of FoxO1. FoxK1/FoxK2 translocation to the nucleus is dependent on the Akt-mTOR pathway, while its localization to the cytoplasm in the basal state is dependent on GSK3. Knockdown of FoxK1 and FoxK2 in liver cells results in upregulation of genes related to apoptosis and down-regulation of genes involved in cell cycle and lipid metabolism. This is associated with decreased cell proliferation and altered mitochondrial fatty acid metabolism. Thus, FoxK1/K2 are reciprocally regulated to FoxO1 following insulin stimulation and play a critical role in the control of apoptosis, metabolism and mitochondrial function. Insulin signaling represses Forkhead transcription factor FoxO activity, which contributes to organismal metabolism. Here, the authors use proteomics to identify positively regulated insulin signaling targets FoxK1/K2 and demonstrate their role in lipid metabolism and mitochondrial regulation.
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Affiliation(s)
- Masaji Sakaguchi
- Sections of Integrative Physiology and Metabolism and Islet Cell Biology and Regenerative Medicine, Joslin Diabetes Center, Boston, MA, 02215, USA.,Department of Medicine, Harvard Medical School, Boston, MA, 02215, USA.,Department of Metabolic Medicine, Kumamoto University, 1-1-1 Honjo, Chuoku, Kumamoto, 860-8556, Japan
| | - Weikang Cai
- Sections of Integrative Physiology and Metabolism and Islet Cell Biology and Regenerative Medicine, Joslin Diabetes Center, Boston, MA, 02215, USA.,Department of Medicine, Harvard Medical School, Boston, MA, 02215, USA
| | - Chih-Hao Wang
- Sections of Integrative Physiology and Metabolism and Islet Cell Biology and Regenerative Medicine, Joslin Diabetes Center, Boston, MA, 02215, USA.,Department of Medicine, Harvard Medical School, Boston, MA, 02215, USA
| | - Carly T Cederquist
- Sections of Integrative Physiology and Metabolism and Islet Cell Biology and Regenerative Medicine, Joslin Diabetes Center, Boston, MA, 02215, USA.,Department of Medicine, Harvard Medical School, Boston, MA, 02215, USA
| | - Marcos Damasio
- Sections of Integrative Physiology and Metabolism and Islet Cell Biology and Regenerative Medicine, Joslin Diabetes Center, Boston, MA, 02215, USA.,Department of Medicine, Harvard Medical School, Boston, MA, 02215, USA
| | - Erica P Homan
- Sections of Integrative Physiology and Metabolism and Islet Cell Biology and Regenerative Medicine, Joslin Diabetes Center, Boston, MA, 02215, USA.,Department of Medicine, Harvard Medical School, Boston, MA, 02215, USA
| | - Thiago Batista
- Sections of Integrative Physiology and Metabolism and Islet Cell Biology and Regenerative Medicine, Joslin Diabetes Center, Boston, MA, 02215, USA.,Department of Medicine, Harvard Medical School, Boston, MA, 02215, USA
| | - Alfred K Ramirez
- Sections of Integrative Physiology and Metabolism and Islet Cell Biology and Regenerative Medicine, Joslin Diabetes Center, Boston, MA, 02215, USA.,Department of Medicine, Harvard Medical School, Boston, MA, 02215, USA
| | - Manoj K Gupta
- Sections of Integrative Physiology and Metabolism and Islet Cell Biology and Regenerative Medicine, Joslin Diabetes Center, Boston, MA, 02215, USA.,Department of Medicine, Harvard Medical School, Boston, MA, 02215, USA
| | - Martin Steger
- Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, 82152, Martinsried, Germany
| | - Nicolai J Wewer Albrechtsen
- Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, 82152, Martinsried, Germany.,Department of Biomedical Sciences and NNF Centre for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark.,Department of Clinical Proteomics, NNF Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, 2200, Copenhagen, Denmark
| | - Shailendra Kumar Singh
- Department of Host Defense, The World Premier International Research Center Initiative Immunology Frontier Research Center, Osaka, 565-0871, Japan
| | - Eiichi Araki
- Department of Metabolic Medicine, Kumamoto University, 1-1-1 Honjo, Chuoku, Kumamoto, 860-8556, Japan
| | - Matthias Mann
- Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, 82152, Martinsried, Germany
| | - Sven Enerbäck
- Department of Medical Biochemistry and Cell Biology, Institute of Biomedicine, University of Gothenburg, Medicinaregatan 9A, PO. Box. 440, 405 30, Göteborg, Sweden
| | - C Ronald Kahn
- Sections of Integrative Physiology and Metabolism and Islet Cell Biology and Regenerative Medicine, Joslin Diabetes Center, Boston, MA, 02215, USA. .,Department of Medicine, Harvard Medical School, Boston, MA, 02215, USA.
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IPP-1 controls Akt/CREB phosphorylation extension in A 2a adenosine receptor signaling cascade in MIN6 pancreatic β-cell line. Eur J Pharmacol 2019; 850:88-96. [PMID: 30772395 DOI: 10.1016/j.ejphar.2019.02.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 02/12/2019] [Accepted: 02/13/2019] [Indexed: 11/23/2022]
Abstract
Signaling through A2a adenosine receptor specifically prevent pancreatic β-cells (PBCs) loses under diabetogenic conditions. However, signaling mediators of this receptor in PBCs remained unidentified. Thus, we aimed to investigate the possible involvement of PKA/Akt/IPP-1/CREB pathway in MIN6 β-cells. In addition, we investigated IPP-1 role in A2a receptor signaling pathway. The expression of A2a receptor in MIN6 cell line was evaluated by RT-PCR and its functionality confirmed by quantification of cAMP in response to the CGS 21680, an A2a receptor agonist. MTT and Brdu assays were used to evaluate cell viability and proliferation, respectively. PKA activity and insulin release were evaluated using ELISA methods. P-Akt/Akt, p-IPP-1/IPP-1, and p-CREB/CREB levels were assessed using western blotting. IPP-1 knock down assessments was performed using specific siRNA. Our result revealed that MIN6 cells express A2a receptor which actively increased cAMP levels (with EC50 = 2.41 µM) and PKA activity. Activation of this receptor increased cell viability, proliferation and insulin release. Moreover, we mentioned A2a receptor stimulation increased p-Akt, p-IPP-1, and p-CREB levels in dose (max at 10 µM of CGS 21680) and time (max at 30 min after CGS 21680 treatment) dependent manner. Interestingly, herein, we found in IPP-1 knocked down cells, A2a receptor failed to activate Akt and CREB. Altogether, we mentioned that in MIN6 cells A2a receptor increase cell viability, proliferation and insulin release through PKA/Akt/IPP-1/CREB signaling pathway. In addition, we conclude A2a receptor signaling through this pathway is dependent to activation of IPP-1.
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Kim JY, Kim DS, Auh QS, Yi JK, Moon SU, Kim EC. Role of Protein Phosphatase 1 in Angiogenesis and Odontoblastic Differentiation of Human Dental Pulp Cells. J Endod 2018; 43:417-424. [PMID: 28231980 DOI: 10.1016/j.joen.2016.10.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Revised: 09/23/2016] [Accepted: 10/11/2016] [Indexed: 01/21/2023]
Abstract
INTRODUCTION The aims of this study were to examine the immunolocalization of protein phosphatase 1 (PP1) in developing mouse pulp tissue and to explore the role of PP1 in odontoblastic differentiation and in vitro angiogenesis in human dental pulp cells (HDPCs). METHODS Immunolocalization of PP1 was assessed in developing mouse pulp tissue. Odontogenic differentiation was examined by alkaline phosphatase activity, alizarin red staining, and reverse transcriptase polymerase chain reaction. Angiogenesis was evaluated by endothelial cell migration and capillary tube formation. Signaling pathways were analyzed by Western blotting and confocal immunofluorescence. RESULTS PP1 expression was detected in preodontoblasts, odontoblasts, dental pulp cells, and endothelial cells within pulp tissue during the crown formed, root formation, and root completion stages. PP1 messenger RNA (mRNA) and protein levels were up-regulated at the late mineralization stage during odontogenic differentiation of HDPCs. The PP1 activator C2 ceramide increased alkaline phosphatase activity, mineralized nodule formation, and mRNA expression of dentin matrix protein 1 and dentin sialophosphoprotein. In contrast, knockdown by PP1 small interfering RNA inhibited odontoblastic differentiation. Moreover, PP1 activator up-regulated mRNA expression of angiogenic genes in HDPCs and increased the migration and capillary tube formation of endothelial cells, whereas PP1 small interfering RNA showed opposite effects. C2 ceramide increased levels of bone morphogenetic protein 2, phosphorylation of Smad 1/5/8, and mRNA expression of runt-related transcription factor 2 and osterix. CONCLUSIONS This study provides the first evidence that PP1 might be a potent regulator of developing pulp tissue in vivo and odontoblastic differentiation and angiogenesis in HDPCs in vitro and may have clinical implications for pulp/dentin regeneration or reparative dentinogenesis.
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Affiliation(s)
- Ji-Youn Kim
- Department of Oral and Maxillofacial Pathology, School of Dentistry and Research Center for Tooth and Periodontal Regeneration, Kyung Hee University, Seoul, Republic of Korea
| | - Duk-Su Kim
- Department of Conservative Dentistry, School of Dentistry, Kyung Hee University, Seoul, Republic of Korea
| | - Q-Schick Auh
- Department of Oral Medicine, School of Dentistry, Kyung Hee University, Seoul, Republic of Korea
| | - Jin-Kyu Yi
- Department of Conservative Dentistry, School of Dentistry, Kyung Hee University, Seoul, Republic of Korea
| | - Sung Ung Moon
- Department of Oral and Maxillofacial Pathology, School of Dentistry and Research Center for Tooth and Periodontal Regeneration, Kyung Hee University, Seoul, Republic of Korea
| | - Eun-Cheol Kim
- Department of Oral and Maxillofacial Pathology, School of Dentistry and Research Center for Tooth and Periodontal Regeneration, Kyung Hee University, Seoul, Republic of Korea.
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29
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Airo AM, Urbanowski MD, Lopez-Orozco J, You JH, Skene-Arnold TD, Holmes C, Yamshchikov V, Malik-Soni N, Frappier L, Hobman TC. Expression of flavivirus capsids enhance the cellular environment for viral replication by activating Akt-signalling pathways. Virology 2018; 516:147-157. [PMID: 29358114 DOI: 10.1016/j.virol.2018.01.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Revised: 01/04/2018] [Accepted: 01/09/2018] [Indexed: 01/23/2023]
Abstract
Flaviviruses depend on multiple host pathways during their life cycles and have evolved strategies to avoid the innate immune response. Previously, we showed that the West Nile virus capsid protein plays a role in this process by blocking apoptosis. In this study, we examined how expression of capsid proteins from several flaviviruses affects apoptosis and other host processes that impact virus replication. All of the tested capsid proteins protected cells from Fas-dependent apoptosis through a mechanism that requires activated Akt. Capsid expression upregulated other Akt-dependent cellular processes including expression of glucose transporter 1 and mitochondrial metabolism. Protein phosphatase 1, which is known to inactivate Akt, was identified as a DENV capsid interacting protein. This suggests that DENV capsid expression activates Akt by sequestering phosphatases that downregulate phospho-Akt. Capsid-dependent upregulation of Akt would enhance downstream signalling pathways that affect cell survival and metabolism, thus providing a favourable environment for virus replication.
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Affiliation(s)
- Adriana M Airo
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Canada
| | | | | | - Jae Hwan You
- Department of Cell Biology, University of Alberta, Edmonton, Canada
| | | | - Charles Holmes
- Department of Biochemistry, University of Alberta, Edmonton, Canada
| | | | - Natasha Malik-Soni
- Department of Molecular Genetics, University of Toronto, Toronto, Canada
| | - Lori Frappier
- Department of Molecular Genetics, University of Toronto, Toronto, Canada
| | - Tom C Hobman
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Canada; Department of Cell Biology, University of Alberta, Edmonton, Canada; Li Ka Shing Institute of Virology, University of Alberta, Canada; Women & Children's Health Research Institute, University of Alberta, Canada.
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30
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Rieder FJJ, Kastner MT, Hartl M, Puchinger MG, Schneider M, Majdic O, Britt WJ, Djinović-Carugo K, Steininger C. Human cytomegalovirus phosphoproteins are hypophosphorylated and intrinsically disordered. J Gen Virol 2017; 98:471-485. [PMID: 27959783 DOI: 10.1099/jgv.0.000675] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Protein phosphorylation has important regulatory functions in cell homeostasis and is tightly regulated by kinases and phosphatases. The tegument of human cytomegalovirus (CMV) contains not only several proteins reported to be extensively phosphorylated but also cellular protein phosphatases (PP1 and PP2A). To investigate this apparent inconsistency, we evaluated the phosphorylation status of the tegument proteins pUL32 and pp65 by enzymatic dephosphorylation and MS. Enzymatic dephosphorylation with bacterial λ phosphatase, but not with PP1, shifted the pUL32-specific signal on reducing SDS-PAGE from ~150 to ~148 kDa, a mass still much larger than the ~118 kDa obtained from our diffusion studies and from the calculated protein mass of ~113 kDa. Remarkably, inhibition of phosphatases through treatment with the phosphatase inhibitors calyculin A and okadaic acid resulted in a shift to ~190 or ~180 kDa, respectively, indicating that a considerable number of potential phosphorylated residues on pUL32 are not phosphorylated under normal conditions. MS revealed a general state of hypophosphorylation of CMV phosphoproteins with only 17 phosphorylated residues detected on pUL32 and 19 on pp65, respectively. Moreover, bioinformatics analysis shows that the C-terminal two-thirds of pUL32 are intrinsically disordered and that most phosphorylations map to this region. In conclusion, we show that important CMV tegument proteins are indeed phosphorylated, though to a lesser extent than previously reported, and the difference in mobility on SDS-PAGE and calculated mass of pUL32 may not be attributed to phosphorylation but more likely due to the partially intrinsically disordered nature of pUL32.
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Affiliation(s)
- Franz J J Rieder
- Department of Medicine I, Division of Infectious Diseases and Tropical Medicine, Medical University of Vienna, Vienna, Austria
| | - Marie-Theres Kastner
- Department of Medicine I, Division of Infectious Diseases and Tropical Medicine, Medical University of Vienna, Vienna, Austria
| | - Markus Hartl
- Mass Spectrometry Facility, Max F. Perutz Laboratories, Vienna Biocenter, Vienna, Austria
| | - Martin G Puchinger
- Department of Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna, Vienna, Austria
| | - Martina Schneider
- Department of Medicine I, Division of Infectious Diseases and Tropical Medicine, Medical University of Vienna, Vienna, Austria
| | - Otto Majdic
- Center for Pathophysiology, Infectiology and Immunology, Institute of Immunology, Medical University of Vienna, Vienna, Austria
| | - William J Britt
- Department of Pediatrics, Children's Hospital, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Kristina Djinović-Carugo
- Department of Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Ljubljana, Slovenia.,Department of Structural and Computational Biology, Max F. Perutz Laboratories, University of Vienna, Vienna, Austria
| | - Christoph Steininger
- Department of Medicine I, Division of Infectious Diseases and Tropical Medicine, Medical University of Vienna, Vienna, Austria
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31
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Antinozzi C, Corinaldesi C, Giordano C, Pisano A, Cerbelli B, Migliaccio S, Di Luigi L, Stefanantoni K, Vannelli GB, Minisola S, Valesini G, Riccieri V, Lenzi A, Crescioli C. Potential role for the VDR agonist elocalcitol in metabolic control: Evidences in human skeletal muscle cells. J Steroid Biochem Mol Biol 2017; 167:169-181. [PMID: 28042053 DOI: 10.1016/j.jsbmb.2016.12.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Revised: 11/20/2016] [Accepted: 12/20/2016] [Indexed: 12/17/2022]
Abstract
Vitamin D plays a pivotal role to maintain skeletal muscle integrity and health. Vitamin D deficiency characterizes inflammatory myopathy (IM) and diabetes, often overlapping diseases involving skeletal muscle damage. Vitamin D receptor (VDR) agonists likely exert beneficial effects in both IM and metabolic disturbances. We aim to evaluate in vitro the effect of elocalcitol, a non-hypercalcemic VDR agonist, on the biomolecular metabolic machinery of human skeletal muscle cells (Hfsmc), vs. insulin (I). We analyzed GLUT4, Flotillin-1, Caveolin-3 and Caveolin-1 cell expression/localization; mTOR, AKT, ERK and 4E-BP1 phosphorylation; IL-6 myokine release; VDR expression. We investigated in vivo vitamin D status in IM subjects, evaluating VDR muscular expression and serum vitamin D with metabolism-related parameters, as glycemia, triglycerides, cholesterol, resistin and adiponectin. In Hfsmc, elocalcitol exerted an I-like effect, promoting GLUT4 re-localization in Flotillin-1, Caveolin-3 and Caveolin-1 positive sites and mTOR, AKT, ERK, 4E-BP1 activation; it enhanced IL-6 myokine release. IM subjects, all normoglycemic, showed VDR/vitamin D deficiency that, together with high lipidemic and resistin profile, possibly increases the risk to develop metabolic diseases. VDR agonists as elocalcitol may be therapeutic tools for skeletal muscle integrity/function maintenance, an indispensable condition for health homeostasis.
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Affiliation(s)
- Cristina Antinozzi
- Department of Movement, Human and Health Sciences, University of Rome Foro Italico, 00135 Rome, Italy
| | - Clarissa Corinaldesi
- Department of Movement, Human and Health Sciences, University of Rome Foro Italico, 00135 Rome, Italy; Leeds Institute of Rheumatic & Musculoskeletal Medicine, University of Leeds, Leeds, UK
| | - Carla Giordano
- Department of Radiological, Oncological and Pathological Sciences, Sapienza University of Rome, 00161 Rome, Italy
| | - Annalinda Pisano
- Department of Radiological, Oncological and Pathological Sciences, Sapienza University of Rome, 00161 Rome, Italy
| | - Bruna Cerbelli
- Department of Radiological, Oncological and Pathological Sciences, Sapienza University of Rome, 00161 Rome, Italy
| | - Silvia Migliaccio
- Department of Movement, Human and Health Sciences, University of Rome Foro Italico, 00135 Rome, Italy
| | - Luigi Di Luigi
- Department of Movement, Human and Health Sciences, University of Rome Foro Italico, 00135 Rome, Italy
| | - Katia Stefanantoni
- Department of Internal Medicine and Medical Specialities, Sapienza University of Rome, 00161 Rome, Italy
| | | | - Salvatore Minisola
- Department of Internal Medicine and Medical Disciplines, Sapienza University of Rome, 00161 Rome, Italy
| | - Guido Valesini
- Department of Internal Medicine and Medical Specialities, Sapienza University of Rome, 00161 Rome, Italy
| | - Valeria Riccieri
- Department of Internal Medicine and Medical Specialities, Sapienza University of Rome, 00161 Rome, Italy
| | - Andrea Lenzi
- Department of Experimental Medicine, Sapienza University of Rome, 00161 Rome, Italy
| | - Clara Crescioli
- Department of Movement, Human and Health Sciences, University of Rome Foro Italico, 00135 Rome, Italy.
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Zhang Y, Huang B, Wang HY, Chang A, Zheng XFS. Emerging Role of MicroRNAs in mTOR Signaling. Cell Mol Life Sci 2017; 74:2613-2625. [PMID: 28238105 DOI: 10.1007/s00018-017-2485-1] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Revised: 02/01/2017] [Accepted: 02/06/2017] [Indexed: 12/15/2022]
Abstract
Mechanistic target of rapamycin (mTOR) is a conserved serine/threonine kinase that plays a critical role in the control of cellular growth and metabolism. Hyperactivation of mTOR pathway is common in human cancers, driving uncontrolled proliferation. MicroRNA (miRNA) is a class of short noncoding RNAs that regulate the expression of a wide variety of genes. Deregulation of miRNAs is a hallmark of cancer. Recent studies have revealed interplays between miRNAs and the mTOR pathway during cancer development. Such interactions appear to provide a fine-tuning of various cellular functions and contribute qualitatively to the behavior of cancer. Here we provide an overview of current knowledge regarding the reciprocal relationship between miRNAs and mTOR pathway: regulation of mTOR signaling by miRNAs and control of miRNA biogenesis by mTOR. Further research in this area may prove important for the diagnosis and therapy of human cancer.
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Affiliation(s)
- Yanjie Zhang
- Oncology Department, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 201999, China.
| | - Bo Huang
- Oncology Department, Shanghai Ninth People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 201999, China
| | - Hui-Yun Wang
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-Sen University Cancer Center, Guangzhou, 510060, China.,Rutgers Robert Wood Johnson Medical School, 675 Hoes Lane West, Piscataway, NJ, 08854, USA.,Rutgers Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, 195 Little Albany Street, New Brunswick, NJ, 08903, USA
| | - Augustus Chang
- Rutgers Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, 195 Little Albany Street, New Brunswick, NJ, 08903, USA
| | - X F Steven Zheng
- State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-Sen University Cancer Center, Guangzhou, 510060, China. .,Rutgers Robert Wood Johnson Medical School, 675 Hoes Lane West, Piscataway, NJ, 08854, USA. .,Rutgers Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, 195 Little Albany Street, New Brunswick, NJ, 08903, USA.
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Abbaoui B, Telu KH, Lucas CR, Thomas-Ahner JM, Schwartz SJ, Clinton SK, Freitas MA, Mortazavi A. The impact of cruciferous vegetable isothiocyanates on histone acetylation and histone phosphorylation in bladder cancer. J Proteomics 2017; 156:94-103. [PMID: 28132875 DOI: 10.1016/j.jprot.2017.01.013] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2016] [Revised: 12/07/2016] [Accepted: 01/25/2017] [Indexed: 12/17/2022]
Abstract
Cruciferous vegetable intake is associated with reduced risk of bladder cancer, yet mechanisms remain unclear. Cruciferous vegetable isothiocyanates (ITCs), namely sulforaphane (SFN) and erucin (ECN), significantly inhibit histone deacetylase (HDAC) activity in human bladder cancer cells representing superficial to invasive biology (59-83% inhibition with 20μM, 48h treatment), and in bladder cancer xenografts (59±3% ECN inhibition). Individual HDACs inhibited by SFN and ECN include HDACs 1, 2, 4 and 6. Interestingly, global acetylation status of histones H3 or H4 remain unaltered. The interplay between HDAC inhibition and modest modulation of AcH3 and AcH4 status is partially explained by decreased histone acetyl transferase activity (48.8±5.3%). In contrast, a significant decrease in phosphorylation status of all isoforms of histone H1 was observed, concomitant with increased phosphatase PP1β and PP2A activity. Together, these findings suggest that ITCs modulate histone status via HDAC inhibition and phosphatase enhancement. This allows for reduced levels of histone H1 phosphorylation, a marker correlated with human bladder cancer progression. Therefore, ITC-mediated inhibition of histone H1 phosphorylation presents a novel direction of research in elucidating epidemiological relationships and supports future food-based prevention strategies. SIGNIFICANCE Collectively, our findings suggest that the cruciferous vegetable isothiocyanates: sulforaphane (SFN) and erucin (ECN), impact histones status in bladder cancer cells by modulating specific HDACs and HATs, and enhancing phosphatase activity, resulting in reduction of histone H1 phosphorylation. These findings are significant due to the fact that our previous work positively correlated histone H1 phosphorylation with bladder cancer carcinogenesis and progression. Therefore, we propose that SFN and ECN may inhibit bladder carcinogenesis via epigenetic modulation of gene expression associated with histone H1 phosphorylation. These efforts may elucidate biomarkers useful in epidemiologic studies related to cruciferous vegetable intake and cancer risk or provide intermediate biomarkers for food-based clinical intervention studies in high-risk cohorts.
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Affiliation(s)
- Besma Abbaoui
- The Integrated Biomedical Science Graduate Program, College of Medicine, The Ohio State University, Columbus, OH 43210, USA
| | - Kelly H Telu
- Department of Chemistry, College of Arts and Sciences, The Ohio State University, Columbus, OH 43210, USA; Comprehensive Cancer Center, The Ohio State University, Columbus, OH 43210, USA
| | - Christopher R Lucas
- The Integrated Biomedical Science Graduate Program, College of Medicine, The Ohio State University, Columbus, OH 43210, USA
| | | | - Steven J Schwartz
- Comprehensive Cancer Center, The Ohio State University, Columbus, OH 43210, USA; Department of Food Science and Technology, College of Food, Agricultural, and Environmental Sciences, The Ohio State University, Columbus, OH 43210, USA
| | - Steven K Clinton
- Comprehensive Cancer Center, The Ohio State University, Columbus, OH 43210, USA; Division of Medical Oncology, Department of Internal Medicine, College of Medicine; The Ohio State University, Columbus, OH 43210, USA
| | - Michael A Freitas
- Comprehensive Cancer Center, The Ohio State University, Columbus, OH 43210, USA; Department of Molecular Virology, Immunology and Medical Genetics, College of Medicine, The Ohio State University, Columbus, OH 43210, USA.
| | - Amir Mortazavi
- Comprehensive Cancer Center, The Ohio State University, Columbus, OH 43210, USA; Division of Medical Oncology, Department of Internal Medicine, College of Medicine; The Ohio State University, Columbus, OH 43210, USA.
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Grabinski T, Kanaan NM. Novel Non-phosphorylated Serine 9/21 GSK3β/α Antibodies: Expanding the Tools for Studying GSK3 Regulation. Front Mol Neurosci 2016; 9:123. [PMID: 27909397 PMCID: PMC5112268 DOI: 10.3389/fnmol.2016.00123] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Accepted: 11/02/2016] [Indexed: 12/25/2022] Open
Abstract
Glycogen synthase kinase 3 (GSK3) β and α are serine/threonine kinases involved in many biological processes. A primary mechanism of GSK3 activity regulation is phosphorylation of N-terminal serine (S) residues (S9 in GSK3β, S21 in GSK3α). Phosphorylation is inhibitory to GSK3 kinase activity because the phosphorylated N-terminus acts as a competitive inhibitor for primed substrates. Despite widespread interest in GSK3 across most fields of biology, the research community does not have reagents that specifically react with nonphosphoS9/21 GSK3β/α (the so-called "active" form). Here, we describe two novel monoclonal antibodies that specifically react with nonphosphoS9/21 GSK3β/α in multiple species (human, mouse, and rat). One of the antibodies is specific for nonphospho-S9 GSK3β (clone 12B2) and one for nonphospho-S9/21 GSK3β/α (clone 15C2). These reagents were validated for specificity and reactivity in several biochemical and immunochemical assays, and they show linear detection of nonphosphoS GSK3. Finally, these reagents provide significant advantages in studying GSK3β regulation. We used both antibodies to study the regulation of S9 phosphorylation by Akt and protein phosphatases. We used 12B2 (due to its specificity for GSK3β) and to demonstrate that protein phosphatase inhibition reduces nonphospho-S9 GSK3β levels and lowers kinase activity within cells. The ability to use the same reagent across biochemical, immunohistological and kinase activity assays provides a powerful approach for studying serine-dependent regulation of GSK3β/α.
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Affiliation(s)
- Tessa Grabinski
- Department of Translational Science and Molecular Medicine, College of Human Medicine, Michigan State University, Grand RapidsMI, USA
| | - Nicholas M. Kanaan
- Department of Translational Science and Molecular Medicine, College of Human Medicine, Michigan State University, Grand RapidsMI, USA
- Hauenstein Neuroscience Center, Mercy Health Saint Mary’s, Grand RapidsMI, USA
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35
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Liu J, Luo Z, Zhang L, Wang L, Nie Q, Wang ZF, Huang Z, Hu X, Gong L, Arrigo AP, Tang X, Xiang JW, Liu F, Deng M, Ji W, Hu W, Zhu JY, Chen B, Bridge J, Hollingsworth MA, Gigantelli J, Liu Y, Nguyen QD, Li DWC. The small heat shock protein αA-crystallin negatively regulates pancreatic tumorigenesis. Oncotarget 2016; 7:65808-65824. [PMID: 27588467 PMCID: PMC5323194 DOI: 10.18632/oncotarget.11668] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Accepted: 08/14/2016] [Indexed: 12/12/2022] Open
Abstract
Our recent study has shown that αA-crystallin appears to act as a tumor suppressor in pancreas. Here, we analyzed expression patterns of αA-crystallin in the pancreatic tumor tissue and the neighbor normal tissue from 74 pancreatic cancer patients and also pancreatic cancer cell lines. Immunocytochemistry revealed that αA-crystallin was highly expressed in the normal tissue from 56 patients, but barely detectable in the pancreatic tumor tissue. Moreover, a low level of αA-crystallin predicts poor prognosis for patients with pancreatic duct adenocarcinoma (PDAC). In the 12 pancreatic cell lines analyzed, except for Capan-1 and Miapaca-2 where the level of αA-crystallin was about 80% and 65% of that in the control cell line, HPNE, the remaining pancreatic cancer cells have much lower αA-crystallin levels. Overexpression of αA-crystallin in MiaPaca-1 cells lacking endogenous αA-crystallin significantly decreased its tumorigenicity ability as shown in the colony formation and wound healing assays. In contrast, knockdown of αA-crystallin in the Capan-1 cells significantly increased its tumorigenicity ability as demonstrated in the above assays. Together, our results further demonstrate that αA-crystallin negatively regulates pancreatic tumorigenesis and appears to be a prognosis biomarker for PDAC.
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Affiliation(s)
- Jifang Liu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong, 510060, China
- Institute of Cancer Research, The Affiliated Tumor Hospital of Guangzhou Medical College, Guangzhou, Guangdong 510095, China
| | - Zhongwen Luo
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong, 510060, China
| | - Lan Zhang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong, 510060, China
| | - Ling Wang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong, 510060, China
- Department of Ophthalmology & Visual Sciences, Truhlsen Eye Institute, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
- Key Laboratory of Protein Chemistry and Developmental Biology, College of Life Sciences, Hunan Normal University, Changsha, Hunan 410081, China
| | - Qian Nie
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong, 510060, China
- Key Laboratory of Protein Chemistry and Developmental Biology, College of Life Sciences, Hunan Normal University, Changsha, Hunan 410081, China
| | - Zheng-Feng Wang
- Department of Ophthalmology & Visual Sciences, Truhlsen Eye Institute, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
- Hepatobiliary Surgery Center of Peking University People's Hospital, Peking University, Beijing 100044, China
| | - Zhaoxia Huang
- Department of Ophthalmology & Visual Sciences, Truhlsen Eye Institute, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
- Key Laboratory of Protein Chemistry and Developmental Biology, College of Life Sciences, Hunan Normal University, Changsha, Hunan 410081, China
| | - Xiaohui Hu
- Department of Ophthalmology & Visual Sciences, Truhlsen Eye Institute, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
- Key Laboratory of Protein Chemistry and Developmental Biology, College of Life Sciences, Hunan Normal University, Changsha, Hunan 410081, China
| | - Lili Gong
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong, 510060, China
| | - Andre-Patrick Arrigo
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong, 510060, China
| | - Xiangcheng Tang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong, 510060, China
| | - Jia-Wen Xiang
- Key Laboratory of Protein Chemistry and Developmental Biology, College of Life Sciences, Hunan Normal University, Changsha, Hunan 410081, China
| | - Fangyuan Liu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong, 510060, China
| | - Mi Deng
- Department of Ophthalmology & Visual Sciences, Truhlsen Eye Institute, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Weike Ji
- Department of Ophthalmology & Visual Sciences, Truhlsen Eye Institute, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Wenfeng Hu
- Department of Ophthalmology & Visual Sciences, Truhlsen Eye Institute, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Ji-Ye Zhu
- Hepatobiliary Surgery Center of Peking University People's Hospital, Peking University, Beijing 100044, China
| | - Baojiang Chen
- Department of Biostatistics, College of Public Health, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Julia Bridge
- Department of Microbiology and Pathology, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Michael A Hollingsworth
- Fred and Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - James Gigantelli
- Department of Ophthalmology & Visual Sciences, Truhlsen Eye Institute, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - Yizhi Liu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong, 510060, China
| | - Quan D Nguyen
- Department of Ophthalmology & Visual Sciences, Truhlsen Eye Institute, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
| | - David Wan-Cheng Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, Guangdong, 510060, China
- Department of Ophthalmology & Visual Sciences, Truhlsen Eye Institute, College of Medicine, University of Nebraska Medical Center, Omaha, NE 68198, USA
- Key Laboratory of Protein Chemistry and Developmental Biology, College of Life Sciences, Hunan Normal University, Changsha, Hunan 410081, China
- Fred and Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, NE 68198, USA
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Huang SH, Lien JC, Chen CJ, Liu YC, Wang CY, Ping CF, Lin YF, Huang AC, Lin CW. Antiviral Activity of a Novel Compound CW-33 against Japanese Encephalitis Virus through Inhibiting Intracellular Calcium Overload. Int J Mol Sci 2016; 17:ijms17091386. [PMID: 27563890 PMCID: PMC5037666 DOI: 10.3390/ijms17091386] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Revised: 07/26/2016] [Accepted: 08/18/2016] [Indexed: 01/31/2023] Open
Abstract
Japanese encephalitis virus (JEV), a mosquito-borne flavivirus, has five genotypes (I, II, III, IV, and V). JEV genotype I circulates widely in some Asian countries. However, current JEV vaccines based on genotype III strains show low neutralizing capacities against genotype I variants. In addition, JE has no specific treatment, except a few supportive treatments. Compound CW-33, an intermediate synthesized derivative of furoquinolines, was investigated for its antiviral activities against JEV in this study. CW-33 exhibited the less cytotoxicity to Syrian baby hamster kidney (BHK-21) and human medulloblastoma (TE761) cells. CW-33 dose-dependently reduced the cytopathic effect and apoptosis of JEV-infected cells. Supernatant virus yield assay pinpointed CW-33 as having potential anti-JEV activity with IC50 values ranging from 12.7 to 38.5 μM. Time-of-addition assay with CW-33 indicated that simultaneous and post-treatment had no plaque reduction activity, but continuous and simultaneous treatments proved to have highly effective antiviral activity, with IC50 values of 32.7 and 48.5 μM, respectively. CW-33 significantly moderated JEV-triggered Ca2+ overload, which correlated with the recovery of mitochondria membrane potential as well as the activation of Akt/mTOR and Jak/STAT1 signals in treated infected cells. Phosphopeptide profiling by LC-MS/MS revealed that CW-33 upregulated proteins from the enzyme modulator category, such as protein phosphatase inhibitor 2 (I-2), Rho GTPase-activating protein 35, ARF GTPase-activating protein GIT2, and putative 3-phosphoinositide-dependent protein kinase 2. These enzyme modulators identified were associated with the activation of Akt/mTOR and Jak/STAT1 signals. Meanwhile, I-2 treatment substantially inhibited the apoptosis of JEV-infected cells. The results demonstrated that CW-33 exhibited a significant potential in the development of anti-JEV agents.
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Affiliation(s)
- Su-Hua Huang
- Department of Biotechnology, Asia University, Wufeng, Taichung 413, Taiwan.
| | - Jin-Cherng Lien
- School of Pharmacy, China Medical University, Taichung 404, Taiwan.
| | - Chao-Jung Chen
- Proteomics Core Laboratory, Department of Medical Research, China Medical University Hospital, Taichung 404, Taiwan.
| | - Yu-Ching Liu
- Proteomics Core Laboratory, Department of Medical Research, China Medical University Hospital, Taichung 404, Taiwan.
| | - Ching-Ying Wang
- Department of Medical Laboratory Science and Biotechnology, China Medical University, Taichung 404, Taiwan.
| | - Chia-Fong Ping
- Department of Medical Laboratory Science and Biotechnology, China Medical University, Taichung 404, Taiwan.
| | - Yu-Fong Lin
- Department of Medical Laboratory Science and Biotechnology, China Medical University, Taichung 404, Taiwan.
| | - An-Cheng Huang
- Department of Nursing, St. Mary's Junior College of Medicine, Nursing and Management, Yilan County 266, Taiwan.
| | - Cheng-Wen Lin
- Department of Biotechnology, Asia University, Wufeng, Taichung 413, Taiwan.
- Department of Medical Laboratory Science and Biotechnology, China Medical University, Taichung 404, Taiwan.
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Wen S, Liu Y, Yang M, Yang K, Huang J, Feng D. Increased NEK2 in hepatocellular carcinoma promotes cancer progression and drug resistance by promoting PP1/Akt and Wnt activation. Oncol Rep 2016; 36:2193-9. [PMID: 27509921 DOI: 10.3892/or.2016.5009] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 07/13/2016] [Indexed: 01/08/2023] Open
Abstract
NIMA-related expressed kinase 2 (NEK2) participates in the carcinogenesis and progression of certain types of cancer, however, its expression and roles in the development of hepatocellular carcinoma (HCC) remains unknown. Here, we found that NEK2 expression was significantly upregulated in both human HCC tissues and cell lines, and increased NEK2 expression in HCC was significantly correlated with clinical progression of HCC in patients. Knockdown of NEK2 in HCC cells inhibited HCC progression, as determined by the suppressed cell proliferation, invasion and metastasis. Furthermore, knockdown of NEK2 inhibited drug resistance of HCC cells, as shown by the promoted suppression of cell viability in 5-fluorouracil (5‑FU)‑treated HCC cells. Mechanistically, protein phosphatase 1 (PP1)/Akt and Wnt signaling activation are significantly inhibited by NEK2 knockdown, which is responsible for the HCC progression and involved in NEK2‑induced cancer cell abnormal biological behavior. Thus, enhanced NEK2 expression in HCC promotes HCC progression and drug resistance by promoting PP1/Akt and Wnt pathway activation, which may represent a new therapeutic target for HCC.
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Affiliation(s)
- Sailan Wen
- Department of Pathology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, P.R. China
| | - Yuwu Liu
- Department of Morphology, The Institute of Advanced Occupation Technology, Xinjiang Medical University, Urumqi, Xinjiang 830011, P.R. China
| | - Manyi Yang
- National Hepatobiliary and Enteric Surgery Research Center, Department of Surgery, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China
| | - Keda Yang
- Department of Pathology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China
| | - Jianghai Huang
- Department of Pathology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, P.R. China
| | - Deyun Feng
- Department of Pathology, School of Basic Medical Sciences, Central South University, Changsha, Hunan 410013, P.R. China
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Cvekl A, Callaerts P. PAX6: 25th anniversary and more to learn. Exp Eye Res 2016; 156:10-21. [PMID: 27126352 DOI: 10.1016/j.exer.2016.04.017] [Citation(s) in RCA: 86] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Revised: 04/12/2016] [Accepted: 04/22/2016] [Indexed: 01/29/2023]
Abstract
The DNA-binding transcription factor PAX6 was cloned 25 years ago by multiple teams pursuing identification of human and mouse eye disease causing genes, cloning vertebrate homologues of pattern-forming regulatory genes identified in Drosophila, or abundant eye-specific transcripts. Since its discovery in 1991, genetic, cellular, molecular and evolutionary studies on Pax6 mushroomed in the mid 1990s leading to the transformative thinking regarding the genetic program orchestrating both early and late stages of eye morphogenesis as well as the origin and evolution of diverse visual systems. Since Pax6 is also expressed outside of the eye, namely in the central nervous system and pancreas, a number of important insights into the development and function of these organs have been amassed. In most recent years, genome-wide technologies utilizing massively parallel DNA sequencing have begun to provide unbiased insights into the regulatory hierarchies of specification, determination and differentiation of ocular cells and neurogenesis in general. This review is focused on major advancements in studies on mammalian eye development driven by studies of Pax6 genes in model organisms and future challenges to harness the technology-driven opportunities to reconstruct, step-by-step, the transition from naïve ectoderm, neuroepithelium and periocular mesenchyme/neural crest cells into the three-dimensional architecture of the eye.
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Affiliation(s)
- Ales Cvekl
- The Department of Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; The Department of Genetics, Albert Einstein College of Medicine, Bronx, NY, 10461, USA.
| | - Patrick Callaerts
- Laboratory of Behavioral and Developmental Genetics, K.U. Leuven, VIB, 3000, Leuven, Belgium.
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Improvement in glycemia after glucose or insulin overload in leptin-infused rats is associated with insulin-related activation of hepatic glucose metabolism. Nutr Metab (Lond) 2016; 13:19. [PMID: 26937247 PMCID: PMC4774133 DOI: 10.1186/s12986-016-0079-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Accepted: 02/25/2016] [Indexed: 11/16/2022] Open
Abstract
Background Insulin regulates glucose homeostasis through direct effects on the liver, among other organs, with leptin modulating insulin’s hepatic actions. Since central leptin may modify insulin signaling in the liver, we hypothesized that leptin infusion activates hepatic glycogen synthesis following peripheral administration of a bolus of glucose or insulin, thus regulating glycemia. Findings Oral glucose and intraperitoneal insulin tolerance tests were performed in control, intracerebroventricular leptin-treated and pair-fed rats during 14 days. An improvement in glycemia and an increase in hepatic free glucose and glycogen concentrations after glucose or insulin overload were observed in leptin-treated rats. In order to analyze whether the liver was involved in these changes, we studied activation of insulin signaling by Western blotting and multiplex bead immunoassay after leptin infusion. Our studies revealed an increase in phosphorylation of insulin receptor substrate-1 and Akt in leptin-treated rats. Examination of parameters related to glucose uptake and metabolism in the liver revealed an augment in glucose transporter 2 and a decrease in phosphoenolpyruvate carboxylase protein levels in this group. Conclusions These results indicate that central leptin increases hepatic insulin signaling, associated with increased glycogen concentrations after glucose or insulin overload, leading to an improvement in glycemia.
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Resveratrol augments ER stress and the cytotoxic effects of glycolytic inhibition in neuroblastoma by downregulating Akt in a mechanism independent of SIRT1. Exp Mol Med 2016; 48:e210. [PMID: 26891914 PMCID: PMC4892869 DOI: 10.1038/emm.2015.116] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Revised: 09/07/2015] [Accepted: 09/22/2015] [Indexed: 12/15/2022] Open
Abstract
Cancer cells typically display increased rates of aerobic glycolysis that are correlated with tumor aggressiveness and a poor prognosis. Targeting the glycolytic pathway has emerged as an attractive therapeutic route mainly because it should spare normal cells. Here, we evaluate the effects of combining the inhibition of glycolysis with application of the polyphenolic compound resveratrol (RSV) in neuroblastoma (NB) cancer cell lines. Inhibiting glycolysis with 2-deoxy-D-glucose (2-DG) significantly reduced NB cell viability and was associated with increased endoplasmic reticulum (ER) stress and Akt activity. Administration of 2-DG increased the expression of the ER molecular chaperones GRP78 and GRP94, the prodeath protein C/EBP homology protein (CHOP) and the phosphorylation of Akt at S473, T450 and T308. Combined treatment with both RSV and 2-DG reduced GRP78, GRP94 and Akt phosphorylation but increased CHOP and NB cell death when compared with the administration of 2-DG alone. The selective inhibition of Akt activity also decreased 2-DG-induced GRP78 and GRP94 expression and increased CHOP expression, suggesting that Akt can modulate ER stress. Protein phosphatase 1α (PP1α) was activated by RSV, as indicated by a reduction in PP1α phosphorylation at T320. Pretreatment of cells with tautomycin, a selective PP1α inhibitor, prevented the RSV-mediated decrease in Akt phosphorylation, suggesting that RSV enhances 2-DG-induced cell death by activating PP1 and downregulating Akt. The RSV-mediated inhibition of Akt in the presence of 2-DG was not prevented by the selective inhibition of SIRT1, a known target of RSV, indicating that the effects of RSV on this pathway are independent of SIRT1. We propose that RSV inhibits Akt activity by increasing PP1α activity, thereby potentiating 2-DG-induced ER stress and NB cell death.
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Tsai JS, Chao CH, Lin LY. Cadmium Activates Multiple Signaling Pathways That Coordinately Stimulate Akt Activity to Enhance c-Myc mRNA Stability. PLoS One 2016; 11:e0147011. [PMID: 26751215 PMCID: PMC4709241 DOI: 10.1371/journal.pone.0147011] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Accepted: 12/28/2015] [Indexed: 01/07/2023] Open
Abstract
Cadmium is a known environmental carcinogen. Exposure of Cd leads to the activation of several proto-oncogenes in cells. We investigated here the mechanism of c-Myc expression in hepatic cells under Cd treatment. The c-Myc protein and mRNA levels increased in dose- and time-dependent manners in HepG2 cells with Cd treatment. This increase was due to an increase in c-Myc mRNA stability. To explore the mechanism involved in enhancing the mRNA stability, several cellular signaling factors that evoked by Cd treatment were analyzed. PI3K, p38, ERK and JNK were activated by Cd. However, ERK did not participate in the Cd-induced c-Myc expression. Further analysis revealed that mTORC2 was a downstream factor of p38. PI3K, JNK and mTORC2 coordinately activated Akt. Akt was phosphorylated at Thr450 in the untreated cells. Cd treatment led to additional phosphorylation at Thr308 and Ser473. Blocking any of the three signaling factors resulted in the reduction of phosphorylation level at all three Akt sites. The activated Akt phosphorylated Foxo1 and allowed the modified protein to translocate into the cytoplasm. We conclude that Cd-induced accumulation of c-Myc requires the activation of several signaling pathways. The signals act coordinately for Akt activation and drive the Foxo1 from the nucleus to the cytoplasm. Reduction of Foxo1 in the nucleus reduces the transcription of its target genes that may affect c-Myc mRNA stability, resulting in a higher accumulation of the c-Myc proteins.
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Affiliation(s)
- Jia-Shiuan Tsai
- Institute of Molecular and Cellular Biology, and Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan, ROC
| | - Cheng-Han Chao
- Division of Nephrology, Department of Internal Medicine, National Taiwan University Hospital Hsin-Chu Branch, Hsinchu, Taiwan, ROC
| | - Lih-Yuan Lin
- Institute of Molecular and Cellular Biology, and Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan, ROC
- * E-mail:
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Sun X, Lin J, Zhang Y, Kang S, Belkin N, Wara AK, Icli B, Hamburg NM, Li D, Feinberg MW. MicroRNA-181b Improves Glucose Homeostasis and Insulin Sensitivity by Regulating Endothelial Function in White Adipose Tissue. Circ Res 2016; 118:810-21. [PMID: 26830849 DOI: 10.1161/circresaha.115.308166] [Citation(s) in RCA: 99] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2015] [Accepted: 01/06/2016] [Indexed: 01/06/2023]
Abstract
RATIONALE The pathogenesis of insulin resistance involves dysregulated gene expression and function in multiple cell types, including endothelial cells (ECs). Post-transcriptional mechanisms such as microRNA-mediated regulation of gene expression could affect insulin action by modulating EC function. OBJECTIVE To determine whether microRNA-181b (miR-181b) affects the pathogenesis of insulin resistance by regulating EC function in white adipose tissue during obesity. METHODS AND RESULTS MiR-181b expression was reduced in adipose tissue ECs of obese mice, and rescue of miR-181b expression improved glucose homeostasis and insulin sensitivity. Systemic intravenous delivery of miR-181b robustly accumulated in adipose tissue ECs, enhanced insulin-mediated Akt phosphorylation at Ser473, and reduced endothelial dysfunction, an effect that shifted macrophage polarization toward an M2 anti-inflammatory phenotype in epididymal white adipose tissue. These effects were associated with increased endothelial nitric oxide synthase and FoxO1 phosphorylation as well as nitric oxide activity in epididymal white adipose tissue. In contrast, miR-181b did not affect insulin-stimulated Akt phosphorylation in liver and skeletal muscle. Bioinformatics and gene profiling approaches revealed that Pleckstrin homology domain leucine-rich repeat protein phosphatase, a phosphatase that dephosphorylates Akt at Ser473, is a novel target of miR-181b. Knockdown of Pleckstrin homology domain leucine-rich repeat protein phosphatase increased Akt phosphorylation at Ser473 in ECs, and phenocopied miR-181b's effects on glucose homeostasis, insulin sensitivity, and inflammation of epididymal white adipose tissue in vivo. Finally, ECs from diabetic subjects exhibited increased Pleckstrin homology domain leucine-rich repeat protein phosphatase expression. CONCLUSIONS Our data underscore the importance of adipose tissue EC function in controlling the development of insulin resistance. Delivery of miR-181b or Pleckstrin homology domain leucine-rich repeat protein phosphatase inhibitors may represent a new therapeutic approach to ameliorate insulin resistance by improving adipose tissue endothelial Akt-endothelial nitric oxide synthase-nitric oxide signaling.
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Affiliation(s)
- Xinghui Sun
- From the Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (X.S., J.L., N.B., A.K.W., B.I., M.W.F.); Department of Cardiology, Institute of Cardiovascular Diseases, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China (J.L., D.L.); Department of Pharmacology and Pharmacy, University of Hong Kong, Pokfulam, Hong Kong SAR, China (Y.Z.); Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Center for Life Sciences, Beth Israel Deaconess Medical Center, Boston, MA (S.K.); and Evans Department of Medicine, Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, MA (N.M.H.)
| | - Jibin Lin
- From the Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (X.S., J.L., N.B., A.K.W., B.I., M.W.F.); Department of Cardiology, Institute of Cardiovascular Diseases, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China (J.L., D.L.); Department of Pharmacology and Pharmacy, University of Hong Kong, Pokfulam, Hong Kong SAR, China (Y.Z.); Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Center for Life Sciences, Beth Israel Deaconess Medical Center, Boston, MA (S.K.); and Evans Department of Medicine, Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, MA (N.M.H.)
| | - Yu Zhang
- From the Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (X.S., J.L., N.B., A.K.W., B.I., M.W.F.); Department of Cardiology, Institute of Cardiovascular Diseases, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China (J.L., D.L.); Department of Pharmacology and Pharmacy, University of Hong Kong, Pokfulam, Hong Kong SAR, China (Y.Z.); Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Center for Life Sciences, Beth Israel Deaconess Medical Center, Boston, MA (S.K.); and Evans Department of Medicine, Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, MA (N.M.H.)
| | - Sona Kang
- From the Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (X.S., J.L., N.B., A.K.W., B.I., M.W.F.); Department of Cardiology, Institute of Cardiovascular Diseases, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China (J.L., D.L.); Department of Pharmacology and Pharmacy, University of Hong Kong, Pokfulam, Hong Kong SAR, China (Y.Z.); Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Center for Life Sciences, Beth Israel Deaconess Medical Center, Boston, MA (S.K.); and Evans Department of Medicine, Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, MA (N.M.H.)
| | - Nathan Belkin
- From the Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (X.S., J.L., N.B., A.K.W., B.I., M.W.F.); Department of Cardiology, Institute of Cardiovascular Diseases, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China (J.L., D.L.); Department of Pharmacology and Pharmacy, University of Hong Kong, Pokfulam, Hong Kong SAR, China (Y.Z.); Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Center for Life Sciences, Beth Israel Deaconess Medical Center, Boston, MA (S.K.); and Evans Department of Medicine, Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, MA (N.M.H.)
| | - Akm K Wara
- From the Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (X.S., J.L., N.B., A.K.W., B.I., M.W.F.); Department of Cardiology, Institute of Cardiovascular Diseases, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China (J.L., D.L.); Department of Pharmacology and Pharmacy, University of Hong Kong, Pokfulam, Hong Kong SAR, China (Y.Z.); Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Center for Life Sciences, Beth Israel Deaconess Medical Center, Boston, MA (S.K.); and Evans Department of Medicine, Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, MA (N.M.H.)
| | - Basak Icli
- From the Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (X.S., J.L., N.B., A.K.W., B.I., M.W.F.); Department of Cardiology, Institute of Cardiovascular Diseases, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China (J.L., D.L.); Department of Pharmacology and Pharmacy, University of Hong Kong, Pokfulam, Hong Kong SAR, China (Y.Z.); Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Center for Life Sciences, Beth Israel Deaconess Medical Center, Boston, MA (S.K.); and Evans Department of Medicine, Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, MA (N.M.H.)
| | - Naomi M Hamburg
- From the Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (X.S., J.L., N.B., A.K.W., B.I., M.W.F.); Department of Cardiology, Institute of Cardiovascular Diseases, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China (J.L., D.L.); Department of Pharmacology and Pharmacy, University of Hong Kong, Pokfulam, Hong Kong SAR, China (Y.Z.); Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Center for Life Sciences, Beth Israel Deaconess Medical Center, Boston, MA (S.K.); and Evans Department of Medicine, Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, MA (N.M.H.)
| | - Dazhu Li
- From the Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (X.S., J.L., N.B., A.K.W., B.I., M.W.F.); Department of Cardiology, Institute of Cardiovascular Diseases, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China (J.L., D.L.); Department of Pharmacology and Pharmacy, University of Hong Kong, Pokfulam, Hong Kong SAR, China (Y.Z.); Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Center for Life Sciences, Beth Israel Deaconess Medical Center, Boston, MA (S.K.); and Evans Department of Medicine, Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, MA (N.M.H.)
| | - Mark W Feinberg
- From the Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA (X.S., J.L., N.B., A.K.W., B.I., M.W.F.); Department of Cardiology, Institute of Cardiovascular Diseases, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China (J.L., D.L.); Department of Pharmacology and Pharmacy, University of Hong Kong, Pokfulam, Hong Kong SAR, China (Y.Z.); Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, Center for Life Sciences, Beth Israel Deaconess Medical Center, Boston, MA (S.K.); and Evans Department of Medicine, Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, MA (N.M.H.).
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Combination of zoledronic acid and serine/threonine phosphatase inhibitors induces synergistic cytotoxicity and apoptosis in human breast cancer cells via inhibition of PI3K/Akt pathway. Tumour Biol 2015; 37:3665-73. [PMID: 26462835 DOI: 10.1007/s13277-015-3265-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Accepted: 02/13/2015] [Indexed: 01/12/2023] Open
Abstract
The aim of this study was to investigate the cytotoxic and apoptotic effects of zoledronic acid (ZA) in combination with serine/threonine protein phosphatase inhibitors, calyculin-A (CA) and okadaic acid (OA), in human MCF-7 and MDA-MB-231 breast cancer cells. XTT cell viability assay was used to evaluate cytotoxicity. DNA fragmentation and caspase-3/7 activity assays were performed to evaluate apoptosis. Activities of phosphatase 1 (PP1) and phosphatase 2A (PP2A) were measured by serine/threonine phosphatase ELISA kit. Expression levels of PI3K, p-PI3K, Akt, p-Akt, Bcl-2, p-Bcl-2, Bad, and p-Bad proteins were evaluated by Western blot analysis. Combination of ZA with either CA or OA showed synergistic cytotoxicity and apoptosis as compared to any agent alone in both MCF-7 and MDA-MB-231 breast cancer cells. Combination treatment also resulted in inhibition of both PP1 and PP2A activities. Both agents used alone or in combination did not induce significant changes in total PI3K, Akt, Bcl-2, and Bad expressions, while p-PI3K, p-Akt, p-Bcl-2, and p-Bad levels were reduced by the combination treatment as compared to agents alone. Moreover, apoptotic effect of combination treatment was significantly inhibited in the presence of LY294002, a specific PI3K inhibitor, in both breast cancer cell lines. In conclusion, synergistic apoptotic effect of the combination treatment is correlated with the block of the PI3K/Akt signal pathway in breast cancer cells.
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Abstract
The understanding of manganese (Mn) biology, in particular its cellular regulation and role in neurological disease, is an area of expanding interest. Mn is an essential micronutrient that is required for the activity of a diverse set of enzymatic proteins (e.g., arginase and glutamine synthase). Although necessary for life, Mn is toxic in excess. Thus, maintaining appropriate levels of intracellular Mn is critical. Unlike other essential metals, cell-level homeostatic mechanisms of Mn have not been identified. In this review, we discuss common forms of Mn exposure, absorption, and transport via regulated uptake/exchange at the gut and blood-brain barrier and via biliary excretion. We present the current understanding of cellular uptake and efflux as well as subcellular storage and transport of Mn. In addition, we highlight the Mn-dependent and Mn-responsive pathways implicated in the growing evidence of its role in Parkinson's disease and Huntington's disease. We conclude with suggestions for future focuses of Mn health-related research.
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Affiliation(s)
- Kyle J Horning
- Department of Neurology, Vanderbilt University, Nashville, Tennessee 37232; , ,
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Signaling related with biphasic effects of bisphenol A (BPA) on Sertoli cell proliferation: A comparative proteomic analysis. Biochim Biophys Acta Gen Subj 2014; 1840:2663-73. [DOI: 10.1016/j.bbagen.2014.05.018] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2014] [Revised: 05/02/2014] [Accepted: 05/07/2014] [Indexed: 01/15/2023]
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Investigation of inflammation and tissue patterning in the gut using a Spatially Explicit General-purpose Model of Enteric Tissue (SEGMEnT). PLoS Comput Biol 2014; 10:e1003507. [PMID: 24675765 PMCID: PMC3967920 DOI: 10.1371/journal.pcbi.1003507] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2013] [Accepted: 01/10/2014] [Indexed: 01/22/2023] Open
Abstract
The mucosa of the intestinal tract represents a finely tuned system where tissue structure strongly influences, and is turn influenced by, its function as both an absorptive surface and a defensive barrier. Mucosal architecture and histology plays a key role in the diagnosis, characterization and pathophysiology of a host of gastrointestinal diseases. Inflammation is a significant factor in the pathogenesis in many gastrointestinal diseases, and is perhaps the most clinically significant control factor governing the maintenance of the mucosal architecture by morphogenic pathways. We propose that appropriate characterization of the role of inflammation as a controller of enteric mucosal tissue patterning requires understanding the underlying cellular and molecular dynamics that determine the epithelial crypt-villus architecture across a range of conditions from health to disease. Towards this end we have developed the Spatially Explicit General-purpose Model of Enteric Tissue (SEGMEnT) to dynamically represent existing knowledge of the behavior of enteric epithelial tissue as influenced by inflammation with the ability to generate a variety of pathophysiological processes within a common platform and from a common knowledge base. In addition to reproducing healthy ileal mucosal dynamics as well as a series of morphogen knock-out/inhibition experiments, SEGMEnT provides insight into a range of clinically relevant cellular-molecular mechanisms, such as a putative role for Phosphotase and tensin homolog/phosphoinositide 3-kinase (PTEN/PI3K) as a key point of crosstalk between inflammation and morphogenesis, the protective role of enterocyte sloughing in enteric ischemia-reperfusion and chronic low level inflammation as a driver for colonic metaplasia. These results suggest that SEGMEnT can serve as an integrating platform for the study of inflammation in gastrointestinal disease.
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Korrodi-Gregório L, Silva JV, Santos-Sousa L, Freitas MJ, Felgueiras J, Fardilha M. TGF-β cascade regulation by PPP1 and its interactors -impact on prostate cancer development and therapy. J Cell Mol Med 2014; 18:555-67. [PMID: 24629090 PMCID: PMC4000109 DOI: 10.1111/jcmm.12266] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Accepted: 01/08/2014] [Indexed: 12/20/2022] Open
Abstract
Protein phosphorylation is a key mechanism by which normal and cancer cells regulate their main transduction pathways. Protein kinases and phosphatases are precisely orchestrated to achieve the (de)phosphorylation of candidate proteins. Indeed, cellular health is dependent on the fine-tune of phosphorylation systems, which when deregulated lead to cancer. Transforming growth factor beta (TGF-β) pathway involvement in the genesis of prostate cancer has long been established. Many of its members were shown to be hypo- or hyperphosphorylated during the process of malignancy. A major phosphatase that is responsible for the vast majority of the serine/threonine dephosphorylation is the phosphoprotein phosphatase 1 (PPP1). PPP1 has been associated with the dephosphorylation of several proteins involved in the TGF-β cascade. This review will discuss the role of PPP1 in the regulation of several TGF-β signalling members and how the subversion of this pathway is related to prostate cancer development. Furthermore, current challenges on the protein phosphatases field as new targets to cancer therapy will be addressed.
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Affiliation(s)
- Luís Korrodi-Gregório
- Signal Transduction Laboratory, Centre for Cell Biology, Biology Department, Health Sciences Department, University of Aveiro, Aveiro, Portugal
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Xu E, Schwab M, Marette A. Role of protein tyrosine phosphatases in the modulation of insulin signaling and their implication in the pathogenesis of obesity-linked insulin resistance. Rev Endocr Metab Disord 2014; 15:79-97. [PMID: 24264858 DOI: 10.1007/s11154-013-9282-4] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Insulin resistance is a major disorder that links obesity to type 2 diabetes mellitus (T2D). It involves defects in the insulin actions owing to a reduced ability of insulin to trigger key signaling pathways in major metabolic tissues. The pathogenesis of insulin resistance involves several inhibitory molecules that interfere with the tyrosine phosphorylation of the insulin receptor and its downstream effectors. Among those, growing interest has been developed toward the protein tyrosine phosphatases (PTPs), a large family of enzymes that can inactivate crucial signaling effectors in the insulin signaling cascade by dephosphorylating their tyrosine residues. Herein we briefly review the role of several PTPs that have been shown to be implicated in the regulation of insulin action, and then focus on the Src homology 2 (SH2) domain-containing SHP1 and SHP2 enzymes, since recent reports have indicated major roles for these PTPs in the control of insulin action and glucose metabolism. Finally, the therapeutic potential of targeting PTPs for combating insulin resistance and alleviating T2D will be discussed.
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Affiliation(s)
- Elaine Xu
- Department of Medicine, Cardiology Axis of the Institut Universitaire de Cardiologie et de Pneumologie de Québec (Hôpital Laval), Ste-Foy, Québec, Canada, G1V 4G2
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Frett B, Brown RV, Ma M, Hu W, Han H, Li HY. Therapeutic melting pot of never in mitosis gene a related kinase 2 (Nek2): a perspective on Nek2 as an oncology target and recent advancements in Nek2 small molecule inhibition. J Med Chem 2014; 57:5835-44. [PMID: 24517277 DOI: 10.1021/jm401719n] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The global incidence of cancer is on the rise, and within the next decade, the disease is expected to become the leading cause of death worldwide. Forthcoming strategies used to treat cancers focus on the design and implementation of multidrug therapies to target complementary cancer specific pathways. A more direct means by which this multitargeted approach can be achieved is by identifying and targeting interpathway regulatory factors. Recent advances in understanding Nek2 (NIMA related kinase 2) biology suggest that the kinase potentially represents a multifaceted therapeutic target. In this regard, pharmacologic modulation of Nek2 with a single agent may effect several mechanisms important for tumor growth, survival, progression, and metastasis. We herein review the development of Nek2 as an oncology target and provide a succinct chronology of drug discovery campaigns focused on targeting Nek2.
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Affiliation(s)
- Brendan Frett
- Department of Pharmacoloy and Toxicology, College of Pharmacy, The University of Arizona , Tucson, Arizona 85721, United States
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Berndt N, Patel R, Yang H, Balasis ME, Sebti SM. Akt2 and acid ceramidase cooperate to induce cell invasion and resistance to apoptosis. Cell Cycle 2013; 12:2024-32. [PMID: 23777806 DOI: 10.4161/cc.25043] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Both Akt 2 and acid ceramidase (ASAH1) are found aberrantly overexpressed in cancer cells, but whether these two enzymes cooperate to induce malignant transformation is not known. We found that in immortalized, non-transformed cells, ectopic co-expression of Akt2 and ASAH1 is significantly more effective than expression of each gene alone at inducing cell invasion and at conferring resistance to apoptosis. Consistent with these observations, siRNA-mediated depletion of both Akt2 and ASAH1 is much more potent than depleting each alone at inhibiting cell viability/proliferation and cell invasion. Furthermore, pharmacological inhibitors of Akt (TCN or MK-2206) and ASAH1 (B13) synergize to inhibit cell viability/proliferation, and combinations of these drugs are more effective than single-agent treatments at inhibiting cell invasion. Taken together, the results suggest that these two enzymes cooperate to induce malignant transformation and warrant further preclinical studies to evaluate the potential of combining inhibitors of Akt and ASAH1 to treat cancer.
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Affiliation(s)
- Norbert Berndt
- Drug Discovery Department and Chemical Biology and Molecular Medicine Program, Moffitt Cancer Center, Tampa, FL, USA
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