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Sarmasti Emami S, Ge A, Zhang D, Hao Y, Ling M, Rubino R, Nicol CJB, Wang W, Yang X. Identification of PTPN12 Phosphatase as a Novel Negative Regulator of Hippo Pathway Effectors YAP/TAZ in Breast Cancer. Int J Mol Sci 2024; 25:4064. [PMID: 38612874 PMCID: PMC11012486 DOI: 10.3390/ijms25074064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Revised: 04/04/2024] [Accepted: 04/04/2024] [Indexed: 04/14/2024] Open
Abstract
The Hippo pathway plays crucial roles in governing various biological processes during tumorigenesis and metastasis. Within this pathway, upstream signaling stimuli activate a core kinase cascade, involving MST1/2 and LATS1/2, that subsequently phosphorylates and inhibits the transcriptional co-activators YAP and its paralog TAZ. This inhibition modulates the transcriptional regulation of downstream target genes, impacting cell proliferation, migration, and death. Despite the acknowledged significance of protein kinases in the Hippo pathway, the regulatory influence of protein phosphatases remains largely unexplored. In this study, we conducted the first gain-of-functional screen for protein tyrosine phosphatases (PTPs) regulating the Hippo pathway. Utilizing a LATS kinase biosensor (LATS-BS), a YAP/TAZ activity reporter (STBS-Luc), and a comprehensive PTP library, we identified numerous novel PTPs that play regulatory roles in the Hippo pathway. Subsequent experiments validated PTPN12, a master regulator of oncogenic receptor tyrosine kinases (RTKs), as a previously unrecognized negative regulator of the Hippo pathway effectors, oncogenic YAP/TAZ, influencing breast cancer cell proliferation and migration. In summary, our findings offer valuable insights into the roles of PTPs in the Hippo signaling pathway, significantly contributing to our understanding of breast cancer biology and potential therapeutic strategies.
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Affiliation(s)
- Sahar Sarmasti Emami
- Department of Pathology and Molecular Medicine, Queen’s University, Kingston, ON K7L 3N6, Canada; (S.S.E.); (A.G.); (D.Z.); (Y.H.); (M.L.); (R.R.); (C.J.B.N.)
| | - Anni Ge
- Department of Pathology and Molecular Medicine, Queen’s University, Kingston, ON K7L 3N6, Canada; (S.S.E.); (A.G.); (D.Z.); (Y.H.); (M.L.); (R.R.); (C.J.B.N.)
| | - Derek Zhang
- Department of Pathology and Molecular Medicine, Queen’s University, Kingston, ON K7L 3N6, Canada; (S.S.E.); (A.G.); (D.Z.); (Y.H.); (M.L.); (R.R.); (C.J.B.N.)
| | - Yawei Hao
- Department of Pathology and Molecular Medicine, Queen’s University, Kingston, ON K7L 3N6, Canada; (S.S.E.); (A.G.); (D.Z.); (Y.H.); (M.L.); (R.R.); (C.J.B.N.)
| | - Min Ling
- Department of Pathology and Molecular Medicine, Queen’s University, Kingston, ON K7L 3N6, Canada; (S.S.E.); (A.G.); (D.Z.); (Y.H.); (M.L.); (R.R.); (C.J.B.N.)
| | - Rachel Rubino
- Department of Pathology and Molecular Medicine, Queen’s University, Kingston, ON K7L 3N6, Canada; (S.S.E.); (A.G.); (D.Z.); (Y.H.); (M.L.); (R.R.); (C.J.B.N.)
| | - Christopher J. B. Nicol
- Department of Pathology and Molecular Medicine, Queen’s University, Kingston, ON K7L 3N6, Canada; (S.S.E.); (A.G.); (D.Z.); (Y.H.); (M.L.); (R.R.); (C.J.B.N.)
| | - Wenqi Wang
- Department of Developmental and Cell Biology, University of California at Irvine, Irvine, CA 92617, USA;
| | - Xiaolong Yang
- Department of Pathology and Molecular Medicine, Queen’s University, Kingston, ON K7L 3N6, Canada; (S.S.E.); (A.G.); (D.Z.); (Y.H.); (M.L.); (R.R.); (C.J.B.N.)
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Liu H, Li X, Shi Y, Ye Z, Cheng X. Protein Tyrosine Phosphatase PRL-3: A Key Player in Cancer Signaling. Biomolecules 2024; 14:342. [PMID: 38540761 PMCID: PMC10967961 DOI: 10.3390/biom14030342] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2024] [Revised: 03/06/2024] [Accepted: 03/08/2024] [Indexed: 07/02/2024] Open
Abstract
Protein phosphatases are primarily responsible for dephosphorylation modification within signal transduction pathways. Phosphatase of regenerating liver-3 (PRL-3) is a dual-specific phosphatase implicated in cancer pathogenesis. Understanding PRL-3's intricate functions and developing targeted therapies is crucial for advancing cancer treatment. This review highlights its regulatory mechanisms, expression patterns, and multifaceted roles in cancer progression. PRL-3's involvement in proliferation, migration, invasion, metastasis, angiogenesis, and drug resistance is discussed. Regulatory mechanisms encompass transcriptional control, alternative splicing, and post-translational modifications. PRL-3 exhibits selective expressions in specific cancer types, making it a potential target for therapy. Despite advances in small molecule inhibitors, further research is needed for clinical application. PRL-3-zumab, a humanized antibody, shows promise in preclinical studies and clinical trials. Our review summarizes the current understanding of the cancer-related cellular function of PRL-3, its prognostic value, and the research progress of therapeutic inhibitors.
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Affiliation(s)
- Haidong Liu
- Zhejiang Cancer Hospital, Hangzhou 310022, China;
- Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Hangzhou 310018, China
| | - Xiao Li
- The Second Clinical Medical College, Zhejiang Chinese Medical University, Hangzhou 310053, China;
| | - Yin Shi
- Department of Biochemistry, Zhejiang University School of Medicine, Hangzhou 310058, China;
| | - Zu Ye
- Zhejiang Cancer Hospital, Hangzhou 310022, China;
- Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Hangzhou 310018, China
- Key Laboratory of Prevention, Diagnosis and Therapy of Upper Gastrointestinal Cancer of Zhejiang Province, Hangzhou 310022, China
- Zhejiang Provincial Research Center for Upper Gastrointestinal Tract Cancer, Zhejiang Cancer Hospital, Hangzhou 310022, China
| | - Xiangdong Cheng
- Zhejiang Cancer Hospital, Hangzhou 310022, China;
- Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Hangzhou 310018, China
- Key Laboratory of Prevention, Diagnosis and Therapy of Upper Gastrointestinal Cancer of Zhejiang Province, Hangzhou 310022, China
- Zhejiang Provincial Research Center for Upper Gastrointestinal Tract Cancer, Zhejiang Cancer Hospital, Hangzhou 310022, China
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3
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Mestareehi A, Abu-Farsakh N. Impact of Protein Phosphatase Expressions on the Prognosis of Hepatocellular Carcinoma Patients. ACS OMEGA 2024; 9:10299-10331. [PMID: 38463290 PMCID: PMC10918787 DOI: 10.1021/acsomega.3c07787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 02/02/2024] [Accepted: 02/08/2024] [Indexed: 03/12/2024]
Abstract
The study was conducted to unveil the significance of protein phosphatases in the prognosis of hepatocellular carcinoma (HCC) patients and its related molecular biological attributes as well as to discover novel potential biomarkers for therapeutic significance and diagnostic purposes that may benefit clinical practice. Analyzing a data set from 159 HCC patients using high-throughput phosphoproteomics, we examined the dysregulated expression of protein phosphatases. Employing bioinformatic and pathway analyses, we explored differentially expressed genes linked to protein phosphatases. A protein-protein interaction network was constructed using the search tool for the retrieval of interacting genes/proteins database. We quantified a total of 11,547 phosphorylation sites associated with 4043 phosphoproteins from HCC patients. Within this data set, we identified 105 identified phosphorylation sites associated with protein phosphatases; 28 genes were upregulated and 3 were downregulated in HCC. Enriched pathways using Gene Set Enrichment Analysis encompassed oocyte meiosis, proteoglycans in cancer, the oxytocin signaling pathway, the cGMP-PKG signaling pathway, the vascular smooth muscle, and the cAMP signaling pathway. The Kyoto encyclopedia of genes and genomes (KEGG) analysis highlighted pathways like mitogen-activated protein kinase, AMPK, and PI3K-Akt, indicating potential involvement in HCC progression. Notably, the PPI network identified hub genes, emphasizing their interconnections and potential roles in HCC. In our study, we found significantly upregulated levels of CDC25C, PPP1R13L, and PPP1CA, which emerge as promising avenues. This significant expression could serve as potent diagnostic and prognostic markers to enhance the effectiveness of HCC cancer treatment, offering efficiency and accuracy in patient assessment. The findings regarding protein phosphatases reveal their elevated expression in HCC, correlating with unfavorable prognosis. Moreover, the outcomes of gene ontology and KEGG pathway analyses suggest that protein phosphatases may influence liver cancer by engaging diverse targets and pathways, ultimately fostering the progression of HCC. These results underscore the substantial potential of protein phosphatases as key contributors to HCC's development and advancement. This insight holds promise for identifying therapeutic targets and charting research avenues to enhance the comprehension of the intricate molecular mechanisms underpinning HCC.
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Affiliation(s)
- Aktham Mestareehi
- Department
of Pharmaceutical Sciences, Faculty of Pharmacy, Isra University, P.O. Box 22, Amman 11622, Jordan
- Department
of Pharmaceutical Sciences, School of Pharmacy and Health Sciences, Wayne State University, Detroit, Michigan 48201, United States
- School
of Medicine, The Ohio State University, Columbus, Ohio 43202, United States
| | - Noor Abu-Farsakh
- Department
of Gastroenterology and Hepatology, Internal Medicine Department, Jordan University Hospital, Amman 11942, Jordan
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4
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Samaržija I, Konjevoda P. Extracellular Matrix- and Integrin Adhesion Complexes-Related Genes in the Prognosis of Prostate Cancer Patients' Progression-Free Survival. Biomedicines 2023; 11:2006. [PMID: 37509645 PMCID: PMC10377098 DOI: 10.3390/biomedicines11072006] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 07/12/2023] [Accepted: 07/13/2023] [Indexed: 07/30/2023] Open
Abstract
Prostate cancer is a heterogeneous disease, and one of the main obstacles in its management is the inability to foresee its course. Therefore, novel biomarkers are needed that will guide the treatment options. The extracellular matrix (ECM) is an important part of the tumor microenvironment that largely influences cell behavior. ECM components are ligands for integrin receptors which are involved in every step of tumor progression. An underlying characteristic of integrin activation and ligation is the formation of integrin adhesion complexes (IACs), intracellular structures that carry information conveyed by integrins. By using The Cancer Genome Atlas data, we show that the expression of ECM- and IACs-related genes is changed in prostate cancer. Moreover, machine learning methods revealed that they are a source of biomarkers for progression-free survival of patients that are stratified according to the Gleason score. Namely, low expression of FMOD and high expression of PTPN2 genes are associated with worse survival of patients with a Gleason score lower than 9. The FMOD gene encodes protein that may play a role in the assembly of the ECM and the PTPN2 gene product is a protein tyrosine phosphatase activated by integrins. Our results suggest potential biomarkers of prostate cancer progression.
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Affiliation(s)
- Ivana Samaržija
- Laboratory for Epigenomics, Division of Molecular Medicine, Ruđer Bošković Institute, 10000 Zagreb, Croatia
| | - Paško Konjevoda
- Laboratory for Epigenomics, Division of Molecular Medicine, Ruđer Bošković Institute, 10000 Zagreb, Croatia
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Honda R, Tempaku Y, Sulidan K, Palmer HEF, Mashima K. Phosphorylation/dephosphorylation of PTP-PEST at Serine 39 is crucial for cell migration. J Biochem 2023; 173:73-84. [PMID: 36250939 DOI: 10.1093/jb/mvac084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 10/11/2022] [Accepted: 10/13/2022] [Indexed: 02/07/2023] Open
Abstract
We investigated the molecular details of the role of protein tyrosine phosphatase (PTP)-PEST in cell migration. PTP-PEST knockout mouse embryonic fibroblasts (KO MEFs) and MEF cells expressing a dominant-negative mutant of PTP-PEST showed significant suppression of cell migration compared to MEF cells expressing wild-type PTP-PEST (WT MEFs). Moreover, MEF cells harbouring a constitutively active mutant of PTP-PEST (S39A MEFs) showed a marked decrease in cell migration. In addition, MEF cells with no PTP-PEST or little PTP activity rapidly adhered to fibronectin and made many focal adhesions compared to WT MEF cells. In contrast, S39A MEF cells showed weak adhesion to fibronectin and formed a few focal adhesions. Furthermore, investigating the subcellular localization showed that Ser39-phosphorylated PTP-PEST was favourably situated in the adherent area of the pseudopodia. Therefore, we propose that suppression of PTP-PEST enzyme activity due to Ser39-phosphorylation in pseudopodia and at the leading edge of migrating cells induces rapid and good adherence to the extracellular matrix. Thus, suppression of PTP activity by Ser39-phosphorylation is critical for cell migration. Three amino acid substitutions in human PTP-PEST have been previously reported to alter PTP activity. These amino acid substitutions in mouse PTP-PEST altered the migration of MEF cells in a positive correlation.
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Affiliation(s)
- Reika Honda
- Department of Life Science, Rikkyo (St. Paul's) University, Nishi-Ikebukuro, Toshima-Ku, Tokyo 171-8501, Japan
| | - Yasuko Tempaku
- Department of Life Science, Rikkyo (St. Paul's) University, Nishi-Ikebukuro, Toshima-Ku, Tokyo 171-8501, Japan
| | - Kaidiliayi Sulidan
- Department of Life Science, Rikkyo (St. Paul's) University, Nishi-Ikebukuro, Toshima-Ku, Tokyo 171-8501, Japan
| | - Helen E F Palmer
- Department of Life Science, Rikkyo (St. Paul's) University, Nishi-Ikebukuro, Toshima-Ku, Tokyo 171-8501, Japan
| | - Keisuke Mashima
- Department of Life Science, Rikkyo (St. Paul's) University, Nishi-Ikebukuro, Toshima-Ku, Tokyo 171-8501, Japan.,Life Science Research Center, Rikkyo (St. Paul's) University, Nishi-Ikebukuro, Toshima-Ku, Tokyo 171-8501, Japan
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6
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Syntenin-1-mediated small extracellular vesicles promotes cell growth, migration, and angiogenesis by increasing onco-miRNAs secretion in lung cancer cells. Cell Death Dis 2022; 13:122. [PMID: 35136055 PMCID: PMC8826407 DOI: 10.1038/s41419-022-04594-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 01/17/2022] [Accepted: 01/27/2022] [Indexed: 12/13/2022]
Abstract
Small extracellular vesicles (sEVs) play a pivotal role in tumor progression by mediating intercellular communication in the tumor microenvironment (TME). Syntenin-1 induces malignant tumor progression in various types of human cancers, including human lung cancer and regulates biogenesis of sEVs. However, the function of syntenin-1-regulated sEVs and miRNAs in sEVs remains to be elucidated. In the present study, we aimed to demonstrate the role of oncogenic Ras/syntenin-1 axis in the release of sEVs and elucidate the function of syntenin-1-mediated miRNAs in sEVs in lung cancer progression. The results revealed that oncogenic Ras promoted the release of sEVs by inducing syntenin-1 expression; disruption of syntenin-1 expression impaired the release of sEVs as well as sEV-mediated cancer cell migration and angiogenesis. Moreover, we identified three miRNAs, namely miR-181a, miR-425-5p, and miR-494-3p, as onco-miRNAs loaded into syntenin-1-dependent sEVs. Remarkably, miR-494-3p was highly abundant in sEVs and its release was triggered by syntenin-1 expression and oncogenic Ras. Ectopic expression of the miR-494-3p mimic enhanced the migration and proliferation of lung cancer cells as well as tube formation in endothelial cells; however, the miR-494-3p inhibitor blocked sEV-mediated effects by targeting tyrosine-protein phosphatase nonreceptor type 12 (PTPN12), a tumor suppressor. sEVs promoted tumor growth and angiogenesis by downregulating PTPN12 expression; however, the miR-494-3p inhibitor significantly suppressed these effects in vivo, confirming that miR-494-3p acts as a major onco-miRNA loaded into lung cancer cell-derived sEVs. Eventually, the oncogenic Ras/syntenin-1 axis may induce cancer progression by increasing miR-494-3p loading into sEVs in lung cancer cells in the TME.
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7
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Guo Z, Mo Z. Regulation of endothelial cell differentiation in embryonic vascular development and its therapeutic potential in cardiovascular diseases. Life Sci 2021; 276:119406. [PMID: 33785330 DOI: 10.1016/j.lfs.2021.119406] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 03/05/2021] [Accepted: 03/14/2021] [Indexed: 12/17/2022]
Abstract
During vertebrate development, the cardiovascular system begins operating earlier than any other organ in the embryo. Endothelial cell (EC) forms the inner lining of blood vessels, and its extensive proliferation and migration are requisite for vasculogenesis and angiogenesis. Many aspects of cellular biology are involved in vasculogenesis and angiogenesis, including the tip versus stalk cell specification. Recently, epigenetics has attracted growing attention in regulating embryonic vascular development and controlling EC differentiation. Some proteins that regulate chromatin structure have been shown to be directly implicated in human cardiovascular diseases. Additionally, the roles of important EC signaling such as vascular endothelial growth factor and its receptors, angiopoietin-1 and tyrosine kinase containing immunoglobulin and epidermal growth factor homology domain-2, and transforming growth factor-β in EC differentiation during embryonic vasculature development are briefly discussed in this review. Recently, the transplantation of human induced pluripotent stem cell (iPSC)-ECs are promising approaches for the treatment of ischemic cardiovascular disease including myocardial infarction. Patient-specific iPSC-derived EC is a potential new target to study differences in gene expression or response to drugs. However, clinical application of the iPSC-ECs in regenerative medicine is often limited by the challenges of maintaining cell viability and function. Therefore, novel insights into the molecular mechanisms underlying EC differentiation might provide a better understanding of embryonic vascular development and bring out more effective EC-based therapeutic strategies for cardiovascular diseases.
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Affiliation(s)
- Zi Guo
- Department of Endocrinology, The Third Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Zhaohui Mo
- Department of Endocrinology, The Third Xiangya Hospital, Central South University, Changsha, Hunan, China.
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Chandel S, Manikandan A, Mehta N, Nathan AA, Tiwari RK, Mohapatra SB, Chandran M, Jaleel A, Manoj N, Dixit M. The protein tyrosine phosphatase PTP-PEST mediates hypoxia-induced endothelial autophagy and angiogenesis via AMPK activation. J Cell Sci 2021; 134:jcs250274. [PMID: 33323505 DOI: 10.1242/jcs.250274] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Accepted: 11/23/2020] [Indexed: 12/22/2022] Open
Abstract
Global and endothelial loss of PTP-PEST (also known as PTPN12) is associated with impaired cardiovascular development and embryonic lethality. Although hypoxia is implicated in vascular remodelling and angiogenesis, its effect on PTP-PEST remains unexplored. Here we report that hypoxia (1% oxygen) increases protein levels and catalytic activity of PTP-PEST in primary endothelial cells. Immunoprecipitation followed by mass spectrometry revealed that α subunits of AMPK (α1 and α2, encoded by PRKAA1 and PRKAA2, respectively) interact with PTP-PEST under normoxia but not in hypoxia. Co-immunoprecipitation experiments confirmed this observation and determined that AMPK α subunits interact with the catalytic domain of PTP-PEST. Knockdown of PTP-PEST abrogated hypoxia-mediated tyrosine dephosphorylation and activation of AMPK (Thr172 phosphorylation). Absence of PTP-PEST also blocked hypoxia-induced autophagy (LC3 degradation and puncta formation), which was rescued by the AMPK activator metformin (500 µM). Because endothelial autophagy is a prerequisite for angiogenesis, knockdown of PTP-PEST also attenuated endothelial cell migration and capillary tube formation, with autophagy inducer rapamycin (200 nM) rescuing angiogenesis. In conclusion, this work identifies for the first time that PTP-PEST is a regulator of hypoxia-induced AMPK activation and endothelial autophagy to promote angiogenesis.
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Affiliation(s)
- Shivam Chandel
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras (IIT Madras), Chennai, Tamil Nadu 600036, India
| | - Amrutha Manikandan
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras (IIT Madras), Chennai, Tamil Nadu 600036, India
| | - Nikunj Mehta
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras (IIT Madras), Chennai, Tamil Nadu 600036, India
| | - Abel Arul Nathan
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras (IIT Madras), Chennai, Tamil Nadu 600036, India
| | - Rakesh Kumar Tiwari
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras (IIT Madras), Chennai, Tamil Nadu 600036, India
| | - Samar Bhallabha Mohapatra
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras (IIT Madras), Chennai, Tamil Nadu 600036, India
| | - Mahesh Chandran
- Cardiovascular Disease and Diabetes Biology Program, Rajiv Gandhi Centre for Biotechnology (RGCB), Thyacaud Post, Thiruvananthpuram, Kerala 695014, India
| | - Abdul Jaleel
- Cardiovascular Disease and Diabetes Biology Program, Rajiv Gandhi Centre for Biotechnology (RGCB), Thyacaud Post, Thiruvananthpuram, Kerala 695014, India
| | - Narayanan Manoj
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras (IIT Madras), Chennai, Tamil Nadu 600036, India
| | - Madhulika Dixit
- Department of Biotechnology, Bhupat and Jyoti Mehta School of Biosciences, Indian Institute of Technology Madras (IIT Madras), Chennai, Tamil Nadu 600036, India
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9
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Casey GR, Stains CI. A fluorescent probe for monitoring PTP-PEST enzymatic activity. Analyst 2020; 145:6713-6718. [PMID: 32812952 DOI: 10.1039/d0an00993h] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Phosphatase non-receptor type 12 (PTPN12 or PTP-PEST) is a critical regulator of cell migration, acting as a tumor suppressor in cancer. Decreases in PTP-PEST expression correlate with aggressive phenotypes in hepatocellular carcinoma (HCC). Despite the importance of PTP-PEST in cellular signaling, methods to directly monitor its enzymatic activity are lacking. Herein, we report the design, synthesis, and optimization of a probe to directly monitor PTP-PEST enzymatic activity via a fluorescent readout. This activity sensor, termed pPEST1tide, is capable of detecting as little as 0.2 nM recombinant PTP-PEST. In addition, we demonstrate that this probe can selectively report on PTP-PEST activity using a panel of potential off-target enzymes. In the long-term, this activity probe could be utilized to identify small molecule modulators of PTP-PEST activity as well as provide a prognostic readout for HCC.
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Affiliation(s)
- Garrett R Casey
- Department of Chemistry, University of Nebraska - Lincoln, Lincoln, NE 68588, USA.
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10
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Zhang Q, Liu C, Li Q, Li J, Wu Y, Liu J. MicroRNA-25-5p counteracts oxidized LDL-induced pathological changes by targeting neuronal growth regulator 1 (NEGR1) in human brain micro-vessel endothelial cells. Biochimie 2019; 165:141-149. [PMID: 31365884 DOI: 10.1016/j.biochi.2019.07.020] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Accepted: 07/26/2019] [Indexed: 12/13/2022]
Abstract
MicroRNA-25-5p (miR-25-5p) may be involved in the pathogenesis and processes of vascular diseases. The aim of this study was to investigate the role of miR-25-5p in oxidized low-density lipoprotein (ox-LDL)-treated human brain microvessel endothelial cells (HBMECs) and the underlying mechanisms. RT-qPCR and/or Western blot were used to detect the expression levels of miR-25-5p and neuronal growth regulator 1 (NEGR1). The effect of miR-25-5p overexpression and NEGR1 silencing on cell proliferation, migration, apoptosis and reactive oxygen species (ROS) production of HBMECs were measured by using CCK-8 assay, transwell assay and flow cytometry, respectively. The expression levels of apoptosis-related protein (cleaved caspase-3 and pro-caspase-3) were detected using Western blot, and the nitric oxide (NO) production was measured by a nitric oxide assay kit. The expression level of miR-25-5p was decreased in HBMECs treated with ox-LDL. Compared with the control group, miR-25-5p overexpression significantly promoted the proliferation and migration of HBMECs treated with ox-LDL (p < 0.01). Overexpression of miR-25-5p significantly suppressed cell apoptosis, ROS production and NO reduction of ox-LDL-induced HBMECs (p < 0.01). In addition, the target gene of miR-25-5p was predicted to be NEGR1 through Targetscan online analysis. The effect of NEGR1 silencing on cell proliferation, migration, apoptosis, ROS and NO production of ox-LDL-induced HBMECs was similar to that of miR-25-5p overexpression. Furthermore, miR-25-5p overexpression and NEGR1 silencing significantly downregulated the protein expression levels of JAK2 and STAT3. Thus, miR-25-5p neutralizes the effects of ox-LDL on multiple functions of HBMECs through suppressing the expression of NEGR1 via regulating the JAK/STA signaling pathway.
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Affiliation(s)
- Qi Zhang
- Department of Cerebrovascular Diseases, Blue Cross Brain Hospital Affiliated to Tongji University, Shanghai, 201101, China.
| | - Chun Liu
- Department of Cerebrovascular Diseases, Blue Cross Brain Hospital Affiliated to Tongji University, Shanghai, 201101, China
| | - Qiang Li
- Department of Neurosurgery, Changhai Hospital of Shanghai Affiliated to Naval Military Medical University, Shanghai, 200433, China
| | - Jianan Li
- Department of Neurosurgery, Changhai Hospital of Shanghai Affiliated to Naval Military Medical University, Shanghai, 200433, China
| | - Yina Wu
- Department of Neurosurgery, Changhai Hospital of Shanghai Affiliated to Naval Military Medical University, Shanghai, 200433, China
| | - Jianmin Liu
- Department of Neurosurgery, Changhai Hospital of Shanghai Affiliated to Naval Military Medical University, Shanghai, 200433, China.
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11
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Lee C, Rhee I. Important roles of protein tyrosine phosphatase PTPN12 in tumor progression. Pharmacol Res 2019; 144:73-78. [DOI: 10.1016/j.phrs.2019.04.011] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 03/26/2019] [Accepted: 04/04/2019] [Indexed: 12/27/2022]
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12
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Huang Y, Zhang Y, Ge L, Lin Y, Kwok HF. The Roles of Protein Tyrosine Phosphatases in Hepatocellular Carcinoma. Cancers (Basel) 2018; 10:cancers10030082. [PMID: 29558404 PMCID: PMC5876657 DOI: 10.3390/cancers10030082] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Revised: 03/12/2018] [Accepted: 03/15/2018] [Indexed: 02/08/2023] Open
Abstract
The protein tyrosine phosphatase (PTP) family is involved in multiple cellular functions and plays an important role in various pathological and physiological processes. In many chronic diseases, for example cancer, PTP is a potential therapeutic target for cancer treatment. In the last two decades, dozens of PTP inhibitors which specifically target individual PTP molecules were developed as therapeutic agents. Hepatocellular carcinoma (HCC) is one of the most common malignant tumors and is the second most lethal cancer worldwide due to a lack of effective therapies. Recent studies have unveiled both oncogenic and tumor suppressive functions of PTP in HCC. Here, we review the current knowledge on the involvement of PTP in HCC and further discuss the possibility of targeting PTP in HCC.
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Affiliation(s)
- Yide Huang
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, College of Life Sciences, Fujian Normal University, Fuzhou 350117, China.
- Faculty of Health Sciences, University of Macau, Avenida de Universidade, Taipa, Macau, China.
| | - Yafei Zhang
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, College of Life Sciences, Fujian Normal University, Fuzhou 350117, China.
| | - Lilin Ge
- Faculty of Health Sciences, University of Macau, Avenida de Universidade, Taipa, Macau, China.
- Jiangsu Key Laboratory for Functional Substance of Chinese Medicine, School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing 210023, China.
| | - Yao Lin
- Provincial University Key Laboratory of Cellular Stress Response and Metabolic Regulation, College of Life Sciences, Fujian Normal University, Fuzhou 350117, China.
| | - Hang Fai Kwok
- Faculty of Health Sciences, University of Macau, Avenida de Universidade, Taipa, Macau, China.
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13
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Sui Y, Fu X, Wang Y, Hu W, Zhang T, Liu W, Jiang L, Xing S, Fu X, Xu X. Expression, purification and characterization of a catalytic domain of human protein tyrosine phosphatase non-receptor 12 (PTPN12) in Escherichia coli with FKBP-type PPIase as a chaperon. Protein Expr Purif 2017; 142:45-52. [PMID: 28965803 DOI: 10.1016/j.pep.2017.09.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Revised: 08/25/2017] [Accepted: 09/21/2017] [Indexed: 12/11/2022]
Abstract
Protein tyrosine phosphatase non-receptor type 12 (PTPN12), also known as PTP-PEST, was broadly expressed in hemopoietic cells. Recent research has shown that this enzyme is involved in tumorigenesis, as well as in tumor progression and transfer, as it can suppress multiple oncogenic tyrosine kinases. However, the difficulty of soluble expression of PTP-PEST in prokaryotic cells has resulted in great limitations in investigating its structure and functions. In this study, we successfully carried out soluble expression of the catalytic domain of PTP-PEST (ΔPTP-PEST) in Escherichia coli and performed an enzymatic characterization and kinetics. To confirm expression efficiency, we also induced the expression of the chaperon, FKBP_C. FKBP_C expression indicated efficacious prokaryotic expression of ΔPTP-PEST. In conclusion, our work yielded a practical expression system and two-step chromatography purification method that may serve as a valuable tool for the structural and functional analysis of proteins that are difficult to express in the soluble form in prokaryotic cells.
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Affiliation(s)
- Yuan Sui
- Edmond H. Fischer Signal Transduction Laboratory, School of Life Sciences, Jilin University, Changchun 130012, PR China
| | - Xingye Fu
- Edmond H. Fischer Signal Transduction Laboratory, School of Life Sciences, Jilin University, Changchun 130012, PR China
| | - Yuchen Wang
- Edmond H. Fischer Signal Transduction Laboratory, School of Life Sciences, Jilin University, Changchun 130012, PR China
| | - Weiyan Hu
- Edmond H. Fischer Signal Transduction Laboratory, School of Life Sciences, Jilin University, Changchun 130012, PR China
| | - Tong Zhang
- Edmond H. Fischer Signal Transduction Laboratory, School of Life Sciences, Jilin University, Changchun 130012, PR China
| | - Wanyao Liu
- Edmond H. Fischer Signal Transduction Laboratory, School of Life Sciences, Jilin University, Changchun 130012, PR China
| | - Liyan Jiang
- Core Facilities for Life Science, Jilin University, Changchun 130012, PR China
| | - Shu Xing
- Edmond H. Fischer Signal Transduction Laboratory, School of Life Sciences, Jilin University, Changchun 130012, PR China.
| | - Xueqi Fu
- Edmond H. Fischer Signal Transduction Laboratory, School of Life Sciences, Jilin University, Changchun 130012, PR China.
| | - Xuesong Xu
- Clinical Laboratory of China-Japan Union Hospital, Jilin University, Changchun 130033, PR China.
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14
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Recent advances in understanding the role of protein-tyrosine phosphatases in development and disease. Dev Biol 2017; 428:283-292. [PMID: 28728679 DOI: 10.1016/j.ydbio.2017.03.023] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Revised: 03/01/2017] [Accepted: 03/02/2017] [Indexed: 01/15/2023]
Abstract
Protein-tyrosine phosphatases (PTPs) remove phosphate groups from tyrosine residues, and thereby propagate or inhibit signal transduction, and hence influence cellular processes such as cell proliferation and differentiation. The importance of tightly controlled PTP activity is reflected by the numerous mechanisms employed by the cell to control PTP activity, including a variety of post-translational modifications, and restricted subcellular localization. This review highlights the strides made in the last decade and discusses the important role of PTPs in key aspects of embryonic development: the regulation of stem cell self-renewal and differentiation, gastrulation and somitogenesis during early embryonic development, osteogenesis, and angiogenesis. The tentative importance of PTPs in these processes is highlighted by the diseases that present upon aberrant activity.
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15
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Li H, Yang D, Ning S, Xu Y, Yang F, Yin R, Feng T, Han S, Guo L, Zhang P, Qu W, Guo R, Song C, Xiao P, Zhou C, Xu Z, Sun J, Yu X. Switching of the substrate specificity of protein tyrosine phosphatase N12 by cyclin‐dependent kinase 2 phosphorylation orchestrating 2 oncogenic pathways. FASEB J 2017; 32:73-82. [PMID: 28842430 DOI: 10.1096/fj.201700418r] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2017] [Accepted: 08/14/2017] [Indexed: 01/27/2023]
Affiliation(s)
- Hui Li
- Key Laboratory Experimental Teratology of the Ministry of EducationShangdong University Jinan China
- Department of PhysiologyShangdong University Jinan China
- Second Hospital, Shangdong University Jinan China
| | - Duxiao Yang
- Department of Molecular Biology and BiochemistryShandong University School of Medicine, Shangdong University Jinan China
| | - Shanglei Ning
- Qilu Hospital and School of Life Science, Shangdong University Jinan China
| | - Yinghui Xu
- Cancer CenterFirst Hospital of Jilin University Jilin China
| | - Fan Yang
- Key Laboratory Experimental Teratology of the Ministry of EducationShangdong University Jinan China
- Department of PhysiologyShangdong University Jinan China
| | - Rusha Yin
- Key Laboratory Experimental Teratology of the Ministry of EducationShangdong University Jinan China
- Department of PhysiologyShangdong University Jinan China
| | - Taihu Feng
- Key Laboratory Experimental Teratology of the Ministry of EducationShangdong University Jinan China
- Department of PhysiologyShangdong University Jinan China
| | - Shouqing Han
- Key Laboratory Experimental Teratology of the Ministry of EducationShangdong University Jinan China
- Department of PhysiologyShangdong University Jinan China
| | - Lu Guo
- Second Hospital, Shangdong University Jinan China
| | - Pengju Zhang
- Department of Molecular Biology and BiochemistryShandong University School of Medicine, Shangdong University Jinan China
| | - Wenjie Qu
- Key Laboratory Experimental Teratology of the Ministry of EducationShangdong University Jinan China
- Department of PhysiologyShangdong University Jinan China
| | - Renbo Guo
- Key Laboratory Experimental Teratology of the Ministry of EducationShangdong University Jinan China
- Department of PhysiologyShangdong University Jinan China
| | - Chen Song
- Center for Quantitative BiologyPeking University Beijing China
| | - Peng Xiao
- Department of Molecular Biology and BiochemistryShandong University School of Medicine, Shangdong University Jinan China
| | | | - Zhigang Xu
- Key Laboratory Experimental Teratology of the Ministry of EducationShangdong University Jinan China
| | - Jin‐Peng Sun
- Department of Molecular Biology and BiochemistryShandong University School of Medicine, Shangdong University Jinan China
- Duke University School of Medicine, Duke University Durham North Carolina USA
| | - Xiao Yu
- Key Laboratory Experimental Teratology of the Ministry of EducationShangdong University Jinan China
- Department of PhysiologyShangdong University Jinan China
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16
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López-Colomé AM, Lee-Rivera I, Benavides-Hidalgo R, López E. Paxillin: a crossroad in pathological cell migration. J Hematol Oncol 2017; 10:50. [PMID: 28214467 PMCID: PMC5316197 DOI: 10.1186/s13045-017-0418-y] [Citation(s) in RCA: 224] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Accepted: 02/08/2017] [Indexed: 02/08/2023] Open
Abstract
Paxilllin is a multifunctional and multidomain focal adhesion adapter protein which serves an important scaffolding role at focal adhesions by recruiting structural and signaling molecules involved in cell movement and migration, when phosphorylated on specific Tyr and Ser residues. Upon integrin engagement with extracellular matrix, paxillin is phosphorylated at Tyr31, Tyr118, Ser188, and Ser190, activating numerous signaling cascades which promote cell migration, indicating that the regulation of adhesion dynamics is under the control of a complex display of signaling mechanisms. Among them, paxillin disassembly from focal adhesions induced by extracellular regulated kinase (ERK)-mediated phosphorylation of serines 106, 231, and 290 as well as the binding of the phosphatase PEST to paxillin have been shown to play a key role in cell migration. Paxillin also coordinates the spatiotemporal activation of signaling molecules, including Cdc42, Rac1, and RhoA GTPases, by recruiting GEFs, GAPs, and GITs to focal adhesions. As a major participant in the regulation of cell movement, paxillin plays distinct roles in specific tissues and developmental stages and is involved in immune response, epithelial morphogenesis, and embryonic development. Importantly, paxillin is also an essential player in pathological conditions including oxidative stress, inflammation, endothelial cell barrier dysfunction, and cancer development and metastasis.
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Affiliation(s)
- Ana María López-Colomé
- Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Apartado Postal 70-253, Ciudad Universitaria, México, 04510, D.F., Mexico.
| | - Irene Lee-Rivera
- Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Apartado Postal 70-253, Ciudad Universitaria, México, 04510, D.F., Mexico
| | - Regina Benavides-Hidalgo
- Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Apartado Postal 70-253, Ciudad Universitaria, México, 04510, D.F., Mexico
| | - Edith López
- Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Apartado Postal 70-253, Ciudad Universitaria, México, 04510, D.F., Mexico
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17
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Transposon mutagenesis identifies genes and cellular processes driving epithelial-mesenchymal transition in hepatocellular carcinoma. Proc Natl Acad Sci U S A 2016; 113:E3384-93. [PMID: 27247392 DOI: 10.1073/pnas.1606876113] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Epithelial-mesenchymal transition (EMT) is thought to contribute to metastasis and chemoresistance in patients with hepatocellular carcinoma (HCC), leading to their poor prognosis. The genes driving EMT in HCC are not yet fully understood, however. Here, we show that mobilization of Sleeping Beauty (SB) transposons in immortalized mouse hepatoblasts induces mesenchymal liver tumors on transplantation to nude mice. These tumors show significant down-regulation of epithelial markers, along with up-regulation of mesenchymal markers and EMT-related transcription factors (EMT-TFs). Sequencing of transposon insertion sites from tumors identified 233 candidate cancer genes (CCGs) that were enriched for genes and cellular processes driving EMT. Subsequent trunk driver analysis identified 23 CCGs that are predicted to function early in tumorigenesis and whose mutation or alteration in patients with HCC is correlated with poor patient survival. Validation of the top trunk drivers identified in the screen, including MET (MET proto-oncogene, receptor tyrosine kinase), GRB2-associated binding protein 1 (GAB1), HECT, UBA, and WWE domain containing 1 (HUWE1), lysine-specific demethylase 6A (KDM6A), and protein-tyrosine phosphatase, nonreceptor-type 12 (PTPN12), showed that deregulation of these genes activates an EMT program in human HCC cells that enhances tumor cell migration. Finally, deregulation of these genes in human HCC was found to confer sorafenib resistance through apoptotic tolerance and reduced proliferation, consistent with recent studies showing that EMT contributes to the chemoresistance of tumor cells. Our unique cell-based transposon mutagenesis screen appears to be an excellent resource for discovering genes involved in EMT in human HCC and potentially for identifying new drug targets.
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18
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Li H, Yang F, Liu C, Xiao P, Xu Y, Liang Z, Liu C, Wang H, Wang W, Zheng W, Zhang W, Ma X, He D, Song X, Cui F, Xu Z, Yi F, Sun JP, Yu X. Crystal Structure and Substrate Specificity of PTPN12. Cell Rep 2016; 15:1345-58. [DOI: 10.1016/j.celrep.2016.04.016] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Revised: 01/27/2016] [Accepted: 03/29/2016] [Indexed: 01/21/2023] Open
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19
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Wang Y, Yan F, Ye Q, Wu X, Jiang F. PTP1B inhibitor promotes endothelial cell motility by activating the DOCK180/Rac1 pathway. Sci Rep 2016; 6:24111. [PMID: 27052191 PMCID: PMC4823726 DOI: 10.1038/srep24111] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Accepted: 03/21/2016] [Indexed: 12/14/2022] Open
Abstract
Promoting endothelial cell (EC) migration is important not only for therapeutic angiogenesis, but also for accelerating re-endothelialization after vessel injury. Several recent studies have shown that inhibition of protein tyrosine phosphatase 1B (PTP1B) may promote EC migration and angiogenesis by enhancing the vascular endothelial growth factor receptor-2 (VEGFR2) signalling. In the present study, we demonstrated that PTP1B inhibitor could promote EC adhesion, spreading and migration, which were abolished by the inhibitor of Rac1 but not RhoA GTPase. PTP1B inhibitor significantly increased phosphorylation of p130Cas, and the interactions among p130Cas, Crk and DOCK180; whereas the phosphorylation levels of focal adhesion kinase, Src, paxillin, or Vav2 were unchanged. Gene silencing of DOCK180, but not Vav2, abrogated the effects of PTP1B inhibitor on EC motility. The effects of PTP1B inhibitor on EC motility and p130Cas/DOCK180 activation persisted in the presence of the VEGFR2 antagonist. In conclusion, we suggest that stimulation of the DOCK180 pathway represents an alternative mechanism of PTP1B inhibitor-stimulated EC motility, which does not require concomitant VEGFR2 activation as a prerequisite. Therefore, PTP1B inhibitor may be a useful therapeutic strategy for promoting EC migration in cardiovascular patients in which the VEGF/VEGFR functions are compromised.
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Affiliation(s)
- Yuan Wang
- Key Laboratory of Cardiovascular Remodelling and Function Research (Chinese Ministry of Education and Chinese Ministry of Health) and The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Qilu Hospital, Shandong University, Jinan, Shandong Province, China
| | - Feng Yan
- Key Laboratory of Cardiovascular Remodelling and Function Research (Chinese Ministry of Education and Chinese Ministry of Health) and The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Qilu Hospital, Shandong University, Jinan, Shandong Province, China
| | - Qing Ye
- Key Laboratory of Cardiovascular Remodelling and Function Research (Chinese Ministry of Education and Chinese Ministry of Health) and The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Qilu Hospital, Shandong University, Jinan, Shandong Province, China
| | - Xiao Wu
- Key Laboratory of Cardiovascular Remodelling and Function Research (Chinese Ministry of Education and Chinese Ministry of Health) and The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Qilu Hospital, Shandong University, Jinan, Shandong Province, China
| | - Fan Jiang
- Key Laboratory of Cardiovascular Remodelling and Function Research (Chinese Ministry of Education and Chinese Ministry of Health) and The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Qilu Hospital, Shandong University, Jinan, Shandong Province, China
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20
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Loss of PTPN12 Stimulates Progression of ErbB2-Dependent Breast Cancer by Enhancing Cell Survival, Migration, and Epithelial-to-Mesenchymal Transition. Mol Cell Biol 2015; 35:4069-82. [PMID: 26391955 DOI: 10.1128/mcb.00741-15] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Accepted: 09/17/2015] [Indexed: 12/15/2022] Open
Abstract
PTPN12 is a cytoplasmic protein tyrosine phosphatase (PTP) reported to be a tumor suppressor in breast cancer, through its capacity to dephosphorylate oncogenic receptor protein tyrosine kinases (PTKs), such as ErbB2. However, the precise molecular and cellular impact of PTPN12 deficiency in breast cancer progression remains to be fully clarified. Here, we addressed this issue by examining the effect of PTPN12 deficiency on breast cancer progression in vivo, in a mouse model of ErbB2-dependent breast cancer using a conditional PTPN12-deficient mouse. Our studies showed that lack of PTPN12 in breast epithelial cells accelerated breast cancer development and lung metastases in vivo. PTPN12-deficient breast cancer cells displayed enhanced tyrosine phosphorylation of the adaptor Cas, the adaptor paxillin, and the kinase Pyk2. They exhibited no detectable increase in ErbB2 tyrosine phosphorylation. PTPN12-deficient cells were more resistant to anoikis and had augmented migratory and invasive properties. Enhanced migration was corrected by inhibiting Pyk2. PTPN12-deficient breast cancer cells also acquired partial features of epithelial-to-mesenchymal transition (EMT), a feature of more aggressive forms of breast cancer. Hence, loss of PTPN12 promoted tumor progression in a mouse model of breast cancer, supporting the notion that PTPN12 is a tumor suppressor in human breast cancer. This function was related to the ability of PTPN12 to suppress cell survival, migration, invasiveness, and EMT and to inhibit tyrosine phosphorylation of Cas, Pyk2, and paxillin. These findings enhance our understanding of the role and mechanism of action of PTPN12 in the control of breast cancer progression.
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21
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Abstract
Although the genetic basis of mitral valve prolapse (MVP) has now been clearly established, the molecular and cellular mechanisms involved in the pathological processes associated to a specific mutation often remain to be determined. The FLNA gene (encoding Filamin A; FlnA) was the first gene associated to non-syndromic X-linked myxomatous valvular dystrophy, but the impacts of the mutations on its function remain un-elucidated. Here, using the first repeats (1-8) of FlnA as a bait in a yeast two-hybrid screen, we identified the tyrosine phosphatase PTPN12 (PTP-PEST) as a specific binding partner of this region of FlnA protein. In addition, using yeast two-hybrid trap assay pull down and co-immunoprecipitation experiments, we showed that the MVP-associated FlnA mutations (G288R, P637Q, H743P) abolished FlnA/PTPN12 interactions. PTPN12 is a key regulator of signaling pathways involved in cell-extracellular matrix (ECM) crosstalk, cellular responses to mechanical stress that involve integrins, focal adhesion transduction pathways, and actin cytoskeleton dynamics. Interestingly, we showed that the FlnA mutations impair the activation status of two PTPN12 substrates, the focal adhesion associated kinase Src, and the RhoA specific activating protein p190RhoGAP. Together, these data point to PTPN12/FlnA interaction and its weakening by FlnA mutations as a mechanism potentially involved in the physiopathology of FlnA-associated MVP.
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22
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Wu SY, Hou HS, Sun YS, Cheng JY, Lo KY. Correlation between cell migration and reactive oxygen species under electric field stimulation. BIOMICROFLUIDICS 2015; 9:054120. [PMID: 26487906 PMCID: PMC4600077 DOI: 10.1063/1.4932662] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Accepted: 09/28/2015] [Indexed: 05/04/2023]
Abstract
Cell migration is an essential process involved in the development and maintenance of multicellular organisms. Electric fields (EFs) are one of the many physical and chemical factors known to affect cell migration, a phenomenon termed electrotaxis or galvanotaxis. In this paper, a microfluidics chip was developed to study the migration of cells under different electrical and chemical stimuli. This chip is capable of providing four different strengths of EFs in combination with two different chemicals via one simple set of agar salt bridges and Ag/AgCl electrodes. NIH 3T3 fibroblasts were seeded inside this chip to study their migration and reactive oxygen species (ROS) production in response to different EF strengths and the presence of β-lapachone. We found that both the EF and β-lapachone level increased the cell migration rate and the production of ROS in an EF-strength-dependent manner. A strong linear correlation between the cell migration rate and the amount of intracellular ROS suggests that ROS are an intermediate product by which EF and β-lapachone enhance cell migration. Moreover, an anti-oxidant, α-tocopherol, was found to quench the production of ROS, resulting in a decrease in the migration rate.
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Affiliation(s)
- Shang-Ying Wu
- Department of Agricultural Chemistry, National Taiwan University , Taipei 10617, Taiwan
| | - Hsien-San Hou
- Research Center for Applied Sciences , Academia Sinica, Taipei 11529, Taiwan
| | - Yung-Shin Sun
- Department of Physics, Fu-Jen Catholic University , New Taipei City 24205, Taiwan
| | - Ji-Yen Cheng
- Research Center for Applied Sciences , Academia Sinica, Taipei 11529, Taiwan
| | - Kai-Yin Lo
- Department of Agricultural Chemistry, National Taiwan University , Taipei 10617, Taiwan
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23
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Duffy EA, Pretorius PR, Lerach S, Lohr JL, Hirsch B, Souza CM, Veillette A, Schimmenti LA. Mosaic partial deletion ofPTPN12in a child with interrupted aortic arch type A. Am J Med Genet A 2015; 167A:2674-83. [DOI: 10.1002/ajmg.a.37279] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2015] [Accepted: 07/17/2015] [Indexed: 11/06/2022]
Affiliation(s)
- Elizabeth A. Duffy
- Division of Genetics and Metabolism; Department of Pediatrics; University of Minnesota; Minneapolis Minnesota
| | - Pamela R. Pretorius
- Division of Genetics and Metabolism; Department of Pediatrics; University of Minnesota; Minneapolis Minnesota
- Department of Biology; Hanover College; Hanover Indiana
| | - Stephanie Lerach
- Division of Genetics and Metabolism; Department of Pediatrics; University of Minnesota; Minneapolis Minnesota
| | - Jamie L. Lohr
- Division of Pediatric Cardiology; Department of Pediatrics; University of Minnesota; Minneapolis Minnesota
- Lillehei Heart Institute; University of Minnesota; Minneapolis Minnesota
| | - Betsy Hirsch
- Department of Laboratory Medicine and Pathology; University of Minnesota; Minneapolis Minnesota
| | - Cleiton M. Souza
- Division of Experimental Medicine; Department of Medicine; McGill University; Montréal Québec Canada
| | - André Veillette
- Division of Experimental Medicine; Department of Medicine; McGill University; Montréal Québec Canada
- Clinical Research Institute of Montréal; Montréal Québec Canada
| | - Lisa A. Schimmenti
- Division of Genetics and Metabolism; Department of Pediatrics; University of Minnesota; Minneapolis Minnesota
- Lillehei Heart Institute; University of Minnesota; Minneapolis Minnesota
- Department of Ophthalmology and Vision Neuroscience; University of Minnesota; Minneapolis Minnesota
- Department of Genetics, Cell Biology and Development; University of Minnesota; Minneapolis Minnesota
- Developmental Biology Center; University of Minnesota; Minneapolis Minnesota
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24
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Protein tyrosine phosphatase-PEST and β8 integrin regulate spatiotemporal patterns of RhoGDI1 activation in migrating cells. Mol Cell Biol 2015; 35:1401-13. [PMID: 25666508 DOI: 10.1128/mcb.00112-15] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Directional cell motility is essential for normal development and physiology, although how motile cells spatiotemporally activate signaling events remains largely unknown. Here, we have characterized an adhesion and signaling unit comprised of protein tyrosine phosphatase (PTP)-PEST and the extracellular matrix (ECM) adhesion receptor β8 integrin that plays essential roles in directional cell motility. β8 integrin and PTP-PEST form protein complexes at the leading edge of migrating cells and balance patterns of Rac1 and Cdc42 signaling by controlling the subcellular localization and phosphorylation status of Rho GDP dissociation inhibitor 1 (RhoGDI1). Translocation of Src-phosphorylated RhoGDI1 to the cell's leading edge promotes local activation of Rac1 and Cdc42, whereas dephosphorylation of RhoGDI1 by integrin-bound PTP-PEST promotes RhoGDI1 release from the membrane and sequestration of inactive Rac1/Cdc42 in the cytoplasm. Collectively, these data reveal a finely tuned regulatory mechanism for controlling signaling events at the leading edge of directionally migrating cells.
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25
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Ambesi A, McKeown-Longo PJ. Conformational remodeling of the fibronectin matrix selectively regulates VEGF signaling. J Cell Sci 2014; 127:3805-16. [PMID: 24982443 DOI: 10.1242/jcs.150458] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The fibronectin matrix plays a crucial role in the regulation of angiogenesis during development, tissue repair and pathogenesis. Previous work has identified a fibronectin-derived homophilic binding peptide, anastellin, as an effective inhibitor of angiogenesis; however, its mechanism of action is not well understood. In the present study, we demonstrate that anastellin selectively inhibits microvessel cell signaling in response to the VEGF165 isoform, but not VEGF121, by preventing the assembly of the complex containing the VEGF receptor and neuropilin-1. Anastellin treatment resulted in the inactivation of α5β1 integrins but was not accompanied by a change in either adhesion complexes or adhesion-based signaling. Integrin inactivation was associated with a masking of the fibronectin synergy site within the extracellular matrix (ECM), indicating that α5β1 inactivation resulted from a decrease in available ligand. These data demonstrate that anastellin influences the microvessel cell response to growth factors by controlling the repertoire of ligated integrins and point to anastellin as an effective regulator of fibronectin matrix organization. These studies further suggest that homophilic fibronectin binding peptides might have novel applications in the field of tissue regeneration as tools to regulate neovascularization.
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Affiliation(s)
- Anthony Ambesi
- Center for Cell Biology and Cancer Research, Albany Medical College, Albany, New York, NY 12208, USA
| | - Paula J McKeown-Longo
- Center for Cell Biology and Cancer Research, Albany Medical College, Albany, New York, NY 12208, USA
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26
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ROS, Notch, and Wnt signaling pathways: crosstalk between three major regulators of cardiovascular biology. BIOMED RESEARCH INTERNATIONAL 2014; 2014:318714. [PMID: 24689035 PMCID: PMC3932294 DOI: 10.1155/2014/318714] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 11/17/2013] [Accepted: 12/28/2013] [Indexed: 12/20/2022]
Abstract
Reactive oxygen species (ROS), traditionally viewed as toxic by-products that cause damage to biomolecules, now are clearly recognized as key modulators in a variety of biological processes and pathological states. The development and regulation of the cardiovascular system require orchestrated activities; Notch and Wnt/β-catenin signaling pathways are implicated in many aspects of them, including cardiomyocytes and smooth muscle cells survival, angiogenesis, progenitor cells recruitment and differentiation, arteriovenous specification, vascular cell migration, and cardiac remodelling. Several novel findings regarding the role of ROS in Notch and Wnt/β-catenin modulation prompted us to review their emerging function in the cardiovascular system during embryogenesis and postnatally.
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27
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Control of dendritic cell migration, T cell-dependent immunity, and autoimmunity by protein tyrosine phosphatase PTPN12 expressed in dendritic cells. Mol Cell Biol 2013; 34:888-99. [PMID: 24366546 DOI: 10.1128/mcb.01369-13] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Dendritic cells (DCs) capture and process antigens in peripheral tissues, migrate to lymphoid tissues, and present the antigens to T cells. PTPN12, also known as PTP-PEST, is an intracellular protein tyrosine phosphatase (PTP) involved in cell-cell and cell-substratum interactions. Herein, we examined the role of PTPN12 in DCs, using a genetically engineered mouse lacking PTPN12 in DCs. Our data indicated that PTPN12 was not necessary for DC differentiation, DC maturation, or cytokine production in response to inflammatory stimuli. However, it was needed for full induction of T cell-dependent immune responses in vivo. This function largely correlated with the need of PTPN12 for DC migration from peripheral sites to secondary lymphoid tissues. Loss of PTPN12 in DCs resulted in hyperphosphorylation of the protein tyrosine kinase Pyk2 and its substrate, the adaptor paxillin. Pharmacological inhibition of Pyk2 or downregulation of Pyk2 expression also compromised DC migration, suggesting that Pyk2 deregulation played a pivotal role in the migration defect caused by PTPN12 deficiency. Together, these findings identified PTPN12 as a key regulator in the ability of DCs to induce antigen-induced T cell responses. This is due primarily to the role of PTPN12 in DC migration from peripheral sites to secondary lymphoid organs through regulation of Pyk2.
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28
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McCole DF. Phosphatase regulation of intercellular junctions. Tissue Barriers 2013; 1:e26713. [PMID: 24868494 DOI: 10.4161/tisb.26713] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2013] [Revised: 10/03/2013] [Accepted: 10/04/2013] [Indexed: 02/06/2023] Open
Abstract
Intercellular junctions represent the key contact points and sites of communication between neighboring cells. Assembly of these junctions is absolutely essential for the structural integrity of cell monolayers, tissues and organs. Disruption of junctions can have severe consequences such as diarrhea, edema and sepsis, and contribute to the development of chronic inflammatory diseases. Cell junctions are not static structures, but rather they represent highly dynamic micro-domains that respond to signals from the intracellular and extracellular environments to modify their composition and function. This review article will focus on the regulation of tight junctions and adherens junctions by phosphatase enzymes that play an essential role in preserving and modulating the properties of intercellular junction proteins.
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Affiliation(s)
- Declan F McCole
- Division of Biomedical Sciences; University of California, Riverside; Riverside, CA USA
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29
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Ayoub E, Hall A, Scott AM, Chagnon MJ, Miquel G, Hallé M, Noda M, Bikfalvi A, Tremblay ML. Regulation of the Src kinase-associated phosphoprotein 55 homologue by the protein tyrosine phosphatase PTP-PEST in the control of cell motility. J Biol Chem 2013; 288:25739-25748. [PMID: 23897807 DOI: 10.1074/jbc.m113.501007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
PTP-PEST is a cytosolic ubiquitous protein tyrosine phosphatase (PTP) that contains, in addition to its catalytic domain, several protein-protein interaction domains that allow it to interface with several signaling pathways. Among others, PTP-PEST is a key regulator of cellular motility and cytoskeleton dynamics. The complexity of the PTP-PEST interactome underscores the necessity to identify its interacting partners and physiological substrates in order to further understand its role in focal adhesion complex turnover and actin organization. Using a modified yeast substrate trapping two-hybrid system, we identified a cytosolic adaptor protein named Src kinase-associated phosphoprotein 55 homologue (SKAP-Hom) as a novel substrate of PTP-PEST. To confirm PTP-PEST interaction with SKAP-Hom, in vitro pull down assays were performed demonstrating that the PTP catalytic domain and Proline-rich 1 (P1) domain are respectively binding to the SKAP-Hom Y260 and Y297 residues and its SH3 domain. Subsequently, we generated and rescued SKAP-Hom-deficient mouse embryonic fibroblasts (MEFs) with WT SKAP-Hom, SKAP-Hom tyrosine mutants (Y260F, Y260F/Y297F), or SKAP-Hom SH3 domain mutant (W335K). Given the role of PTP-PEST, wound-healing and trans-well migration assays were performed using the generated lines. Indeed, SKAP-Hom-deficient MEFs showed a defect in migration compared with WT-rescued MEFs. Interestingly, the SH3 domain mutant-rescued MEFs showed an enhanced cell migration corresponding potentially with higher tyrosine phosphorylation levels of SKAP-Hom. These findings suggest a novel role of SKAP-Hom and its phosphorylation in the regulation of cellular motility. Moreover, these results open new avenues by which PTP-PEST regulates cellular migration, a hallmark of metastasis.
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Affiliation(s)
- Emily Ayoub
- From the Goodman Cancer Research Centre and Department of Biochemistry, McGill University, Montreal, Quebec H3A 1A3, Canada
| | - Anita Hall
- From the Goodman Cancer Research Centre and Department of Biochemistry, McGill University, Montreal, Quebec H3A 1A3, Canada
| | - Adam M Scott
- From the Goodman Cancer Research Centre and Department of Biochemistry, McGill University, Montreal, Quebec H3A 1A3, Canada
| | - Mélanie J Chagnon
- From the Goodman Cancer Research Centre and Department of Biochemistry, McGill University, Montreal, Quebec H3A 1A3, Canada
| | - Géraldine Miquel
- INSERM U1029 and; Université Bordeaux, Avenue des Facultés, 33 405 Talence, France
| | - Maxime Hallé
- From the Goodman Cancer Research Centre and Department of Biochemistry, McGill University, Montreal, Quebec H3A 1A3, Canada
| | - Masaharu Noda
- the Division of Molecular Neurobiology, National Institute for Basic Biology, 5-1 Higashiyama, Myodaiji-cho, Okazaki, Aichi 444-8787, Japan, and
| | - Andreas Bikfalvi
- INSERM U1029 and; Université Bordeaux, Avenue des Facultés, 33 405 Talence, France
| | - Michel L Tremblay
- From the Goodman Cancer Research Centre and Department of Biochemistry, McGill University, Montreal, Quebec H3A 1A3, Canada,.
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30
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Yang S, Roselli F, Patchev AV, Yu S, Almeida OFX. Non-receptor-tyrosine kinases integrate fast glucocorticoid signaling in hippocampal neurons. J Biol Chem 2013; 288:23725-39. [PMID: 23818519 DOI: 10.1074/jbc.m113.470146] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Despite numerous descriptions of rapid effects of corticosterone on neuronal function, the intracellular mechanisms responsible for these changes remain elusive. The present comprehensive analysis reveals that signaling from a membrane-located G protein-coupled receptor activates PKC, Akt/PKB, and PKA, which subsequently trigger the phosphorylation of the tyrosine kinases Pyk2, Src, and Abl. These changes induce rapid cytoskeletal rearrangements (increased PSD-95 co-clustering) within the post-synaptic density; these events are accompanied by increased surface NMDA receptor expression, reflecting corticosterone-induced inhibition of NMDA receptor endocytosis. Notably, none of these signaling mechanisms require de novo protein synthesis. The observed up-regulation of ERK1/2 (downstream of NMDA receptor signaling) together with the fact that c-Abl integrates cytoplasmic and nuclear functions introduces a potential mechanism through which rapid signaling initiated at the plasma membrane may eventually determine the long term integrated response to corticosterone by impacting on the transcriptional machinery that is regulated by classical, nuclear mineralocorticoid, and glucocorticoid receptors.
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Affiliation(s)
- Silei Yang
- Max Planck Institute of Psychiatry, 80804 Munich, Germany
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31
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Nunes-Xavier CE, Martín-Pérez J, Elson A, Pulido R. Protein tyrosine phosphatases as novel targets in breast cancer therapy. Biochim Biophys Acta Rev Cancer 2013; 1836:211-26. [PMID: 23756181 DOI: 10.1016/j.bbcan.2013.06.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2013] [Accepted: 06/01/2013] [Indexed: 02/07/2023]
Abstract
Breast cancer is linked to hyperactivation of protein tyrosine kinases (PTKs), and recent studies have unveiled that selective tyrosine dephosphorylation by protein tyrosine phosphatases (PTPs) of specific substrates, including PTKs, may activate or inactivate oncogenic pathways in human breast cancer cell growth-related processes. Here, we review the current knowledge on the involvement of PTPs in breast cancer, as major regulators of breast cancer therapy-targeted PTKs, such as HER1/EGFR, HER2/Neu, and Src. The functional interplay between PTKs and PTK-activating or -inactivating PTPs, and its implications in novel breast cancer therapies based on targeting of specific PTPs, are discussed.
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Affiliation(s)
- Caroline E Nunes-Xavier
- BioCruces Health Research Institute, Hospital de Cruces, Plaza Cruces s/n, 48903 Barakaldo, Spain
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32
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Macrophage fusion is controlled by the cytoplasmic protein tyrosine phosphatase PTP-PEST/PTPN12. Mol Cell Biol 2013; 33:2458-69. [PMID: 23589331 DOI: 10.1128/mcb.00197-13] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Macrophages can undergo cell-cell fusion, leading to the formation of multinucleated giant cells and osteoclasts. This process is believed to promote the proteolytic activity of macrophages toward pathogens, foreign bodies, and extracellular matrices. Here, we examined the role of PTP-PEST (PTPN12), a cytoplasmic protein tyrosine phosphatase, in macrophage fusion. Using a macrophage-targeted PTP-PEST-deficient mouse, we determined that PTP-PEST was not needed for macrophage differentiation or cytokine production. However, it was necessary for interleukin-4-induced macrophage fusion into multinucleated giant cells in vitro. It was also needed for macrophage fusion following implantation of a foreign body in vivo. Moreover, in the RAW264.7 macrophage cell line, PTP-PEST was required for receptor activator of nuclear factor kappa-B ligand (RANKL)-triggered macrophage fusion into osteoclasts. PTP-PEST had no impact on expression of fusion mediators such as β-integrins, E-cadherin, and CD47, which enable macrophages to become fusion competent. However, it was needed for polarization of macrophages, migration induced by the chemokine CC chemokine ligand 2 (CCL2), and integrin-induced spreading, three key events in the fusion process. PTP-PEST deficiency resulted in specific hyperphosphorylation of the protein tyrosine kinase Pyk2 and the adaptor paxillin. Moreover, a fusion defect was induced upon treatment of normal macrophages with a Pyk2 inhibitor. Together, these data argue that macrophage fusion is critically dependent on PTP-PEST. This function is seemingly due to the ability of PTP-PEST to control phosphorylation of Pyk2 and paxillin, thereby regulating cell polarization, migration, and spreading.
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