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Sohn HA, Kang M, Ha H, Yeom YI, Park KC, Lee DC. R-PTP-κ Inhibits Contact-Dependent Cell Growth by Suppressing E2F Activity. Biomedicines 2022; 10:biomedicines10123199. [PMID: 36551956 PMCID: PMC9775357 DOI: 10.3390/biomedicines10123199] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 12/02/2022] [Accepted: 12/07/2022] [Indexed: 12/14/2022] Open
Abstract
Density-dependent regulation of cell growth is presumed to be caused by cell-cell contact, but the underlying molecular mechanism is not yet clearly defined. Here, we report that receptor-type protein tyrosine phosphatase-kappa (R-PTP-κ) is an important regulator of cell contact-dependent growth inhibition. R-PTP-κ expression increased in proportion to cell density. siRNA-mediated R-PTP-κ downregulation led to the loss of cell contact-mediated growth inhibition, whereas its upregulation reduced anchorage-independent cell growth in soft agar as well as tumor growth in nude mice. Expression profiling and luciferase reporter system-mediated signaling pathway analysis revealed that R-PTP-κ induced under cell contact conditions distinctly suppressed E2F activity. Among the structural domains of R-PTP-κ, the cytoplasmic domain containing the tandemly repeated PTP motif acts as a potent downregulator of the E2F pathway. Specifically, R-PTP-κ suppressed CDK2 activity through the induction of p21Cip1/WAF-1 and p27Kip1, resulting in cell cycle arrest at the G1 phase. In transcriptome-based public datasets generated from four different tumor types, R-PTP-κ expression was negatively correlated with the expression pattern and prognostic value of two known E2F1 target genes (CCNE1 and CDC25A). Therefore, our results indicate that the R-PTP-κ-E2F axis plays a crucial role in cell growth-inhibitory signaling arising from cell-cell contact conditions.
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Affiliation(s)
- Hyun Ahm Sohn
- Personalized Genomic Medicine Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Republic of Korea
| | - Minho Kang
- Personalized Genomic Medicine Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Republic of Korea
| | - Hyunjung Ha
- Department of Biochemistry, School of Life Sciences, Chungbuk National University, Cheongju 28644, Republic of Korea
| | - Young Il Yeom
- Personalized Genomic Medicine Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Republic of Korea
- Department of Functional Genomics, University of Science and Technology (UST), Daejeon 34113, Republic of Korea
| | - Kyung Chan Park
- Personalized Genomic Medicine Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Republic of Korea
- Department of Functional Genomics, University of Science and Technology (UST), Daejeon 34113, Republic of Korea
- Correspondence: (K.C.P.); (D.C.L.); Tel.: +82-42-879-8115 (K.C.P.); +82-42-879-8153 (D.C.L.)
| | - Dong Chul Lee
- Personalized Genomic Medicine Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon 34141, Republic of Korea
- Correspondence: (K.C.P.); (D.C.L.); Tel.: +82-42-879-8115 (K.C.P.); +82-42-879-8153 (D.C.L.)
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Chen Y, Xu C, Harirforoosh S, Luo X, Wang KS. Analysis of PTPRK polymorphisms in association with risk and age at onset of Alzheimer's disease, cancer risk, and cholesterol. J Psychiatr Res 2018; 96:65-72. [PMID: 28987514 PMCID: PMC6195678 DOI: 10.1016/j.jpsychires.2017.09.021] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2017] [Revised: 09/12/2017] [Accepted: 09/21/2017] [Indexed: 12/17/2022]
Abstract
The human receptor-type protein-tyrosine phosphatase kappa (PTPRK) gene is highly expressed in human brain and was previously associated with an increased risk of neuropsychiatric disorders and cancer. This study investigated the association of 52 single nucleotide polymorphisms (SNPs) in PTPRK with the risk and age at onset (AAO) of Alzheimer's disease (AD) in 791 AD patients and 782 controls. Our data analysis showed that five SNPs (top SNP rs4895829 with p = 0.0125) were associated with the risk of AD based on a multiple logistic regression (p < 0.05); while six SNPs (top SNP rs1891150 with p = 8.02 × 10-6) were associated with AAO by using a multiple linear regression analysis. Interestingly, rs2326681 was associated with both the risk and AAO of AD (p = 4.65 × 10-2 and 5.18 × 10-3, respectively). In a replication study, the results from family-based association test - generalized estimating equation (GEE) statistics and Wilcoxon test showed that seven SNPs were associated with the risk of AD (top SNP rs11756545 with p = 1.02 × 10-2) and 12 SNPs were associated with the AAO (top SNP rs11966128 with p = 1.39 × 10-4), respectively. One additional sample showed that four SNPs were associated with risk of cancer (top SNP rs1339197 with p = 4.1 × 10-3), 12 SNPs associated with LDL-cholesterol (top SNP rs4544930 with p = 3.47 × 10-3), and eight SNPs associated with total cholesterol (top SNP rs1012049 with p = 6.09 × 10-3). In addition, the AD associated rs4895829 was associated with the gene expression level in the cerebellum (p = 7.3 × 10-5). The present study is the first study providing evidence of several genetic variants within the PTPRK gene associated with the risk and AAO of AD, risk of cancer, LDL and total cholesterol levels.
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Affiliation(s)
- Yang Chen
- Department of Biostatistics and Epidemiology, College of Public Health, East Tennessee State University, Johnson City, TN 37614, USA
| | - Chun Xu
- Department of Health and Biomedical Sciences, College of Health Affairs, University of Texas Rio Grande Valley, Brownsville, TX 78520, USA
| | - Sam Harirforoosh
- Department of Pharmaceutical Sciences, Gatton College of Pharmacy, ETSU, East Tennessee State University, Johnson City, TN 37614, USA
| | - Xingguang Luo
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT 06516, USA,Biological Psychiatry Research Center, Huilongguan Hospital, Beijing, China,Corresponding author: Kesheng Wang PhD, Department of Biostatistics and Epidemiology, College of Public Health, East Tennessee State University, PO Box 70259, Lamb Hall, Johnson City, TN 37614-1700, USA. Tel.: +1 423 439 4481; fax: +1 423 439 4606; (K.S. Wang), (X. Luo)
| | - Ke-Sheng Wang
- Department of Biostatistics and Epidemiology, College of Public Health, East Tennessee State University, Johnson City, TN 37614, USA; Biological Psychiatry Research Center, Huilongguan Hospital, Beijing, China.
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3
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Januchowski R, Sterzyńska K, Zawierucha P, Ruciński M, Świerczewska M, Partyka M, Bednarek-Rajewska K, Brązert M, Nowicki M, Zabel M, Klejewski A. Microarray-based detection and expression analysis of new genes associated with drug resistance in ovarian cancer cell lines. Oncotarget 2017; 8:49944-49958. [PMID: 28611294 PMCID: PMC5564819 DOI: 10.18632/oncotarget.18278] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Accepted: 04/24/2017] [Indexed: 12/24/2022] Open
Abstract
PURPOSE The present study is to discover a new genes associated with drug resistance development in ovarian cancer. METHODS We used microarray analysis to determine alterations in the level of expression of genes in cisplatin- (CisPt), doxorubicin- (Dox), topotecan- (Top), and paclitaxel- (Pac) resistant variants of W1 and A2780 ovarian cancer cell lines. Immunohistochemistry assay was used to determine protein expression in ovarian cancer patients. RESULTS We observed alterations in the expression of 22 genes that were common to all three cell lines that were resistant to the same cytostatic drug. The level of expression of 13 genes was upregulated and that of nine genes was downregulated. In the CisPt-resistant cell line, we observed downregulated expression of ABCC6, BST2, ERAP2 and MCTP1; in the Pac-resistant cell line, we observe upregulated expression of ABCB1, EPHA7 and RUNDC3B and downregulated expression of LIPG, MCTP1, NSBP1, PCDH9, PTPRK and SEMA3A. The expression levels of three genes, ABCB1, ABCB4 and IFI16, were upregulated in the Dox-resistant cell lines. In the Top-resistant cell lines, we observed increased expression levels of ABCG2, HERC5, IFIH1, MYOT, S100A3, SAMD4A, SPP1 and TGFBI and decreased expression levels of MCTP1 and PTPRK. The expression of EPHA7, IFI16, SPP1 and TGFBI was confirmed at protein level in analyzed ovarian cancer patients.. CONCLUSIONS The expression profiles of the investigated cell lines indicated that new candidate genes are related to the development of resistance to the cytostatic drugs that are used in first- and second-line chemotherapy of ovarian cancer.
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Affiliation(s)
- Radosław Januchowski
- Department of Histology and Embryology, Poznań University of Medical Sciences, Poznań, 60-781, Poland
| | - Karolina Sterzyńska
- Department of Histology and Embryology, Poznań University of Medical Sciences, Poznań, 60-781, Poland
| | - Piotr Zawierucha
- Department of Histology and Embryology, Poznań University of Medical Sciences, Poznań, 60-781, Poland
- Department of Anatomy, Poznań University of Medical Sciences, Poznań, 60-781, Poland
| | - Marcin Ruciński
- Department of Histology and Embryology, Poznań University of Medical Sciences, Poznań, 60-781, Poland
| | - Monika Świerczewska
- Department of Histology and Embryology, Poznań University of Medical Sciences, Poznań, 60-781, Poland
| | - Małgorzata Partyka
- Department of Histology and Embryology, Poznań University of Medical Sciences, Poznań, 60-781, Poland
| | | | - Maciej Brązert
- Division of Infertility and Reproductive Endocrinology, Department of Gynecology, Obstetrics and Gynecological Oncology, Poznań University of Medical Sciences, Poznań, 60-535, Poland
| | - Michał Nowicki
- Department of Histology and Embryology, Poznań University of Medical Sciences, Poznań, 60-781, Poland
| | - Maciej Zabel
- Department of Histology and Embryology, Poznań University of Medical Sciences, Poznań, 60-781, Poland
- Department of Histology and Embryology, Wrocław Medical University, Wrocław, 50-368, Poland
| | - Andrzej Klejewski
- Department of Nursing, Poznań University of Medical Sciences, Poznań, 60-179, Poland
- Departament of Obstetrics and Womens Dieseases, Poznań University of Medical Sciences, Poznań, 60-535, Poland
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Receptor-type tyrosine-protein phosphatase κ directly targets STAT3 activation for tumor suppression in nasal NK/T-cell lymphoma. Blood 2015; 125:1589-600. [PMID: 25612622 DOI: 10.1182/blood-2014-07-588970] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Nasal-type natural killer/T-cell lymphoma (NKTCL) is an aggressive disease characterized by frequent deletions on 6q, and constitutive activation of signal transducer and activator of transcription 3 (STAT3). Phosphorylation at Tyr705 activates STAT3, inducing dimerization, nuclear translocation, and DNA binding. In this study, we investigated whether receptor-type tyrosine-protein phosphatase κ (PTPRK), the only protein tyrosine phosphatase at 6q that contains a STAT3-specifying motif, negatively regulates STAT3 activation in NKTCL. PTPRK was highly expressed in normal NK cells but was underexpressed in 4 of 5 (80%) NKTCL cell lines and 15 of 27 (55.6%) primary tumors. Significantly, PTPRK protein expression was inversely correlated with nuclear phospho-STAT3(Tyr705) expression in NKTCL cell lines (P = .025) and tumors (P = .040). PTPRK restoration decreased nuclear phospho-STAT3(Tyr705) levels, whereas knockdown of PTPRK increased such levels in NKTCL cells. Phosphatase substrate-trapping mutant assays demonstrated the binding of PTPRK to STAT3, and phosphatase assays showed that PTPRK directly dephosphorylated phospho-STAT3(Tyr705). Restoration of PTPRK inhibited tumor cell growth and reduced the migration and invasion ability of NKTCL cells. Monoallelic deletion and promoter hypermethylation caused underexpression of PTPRK messenger RNA in NKTCL, and methylation of the PTPRK promoter significantly correlated with inferior overall survival (P = .049) in NKTCL patients treated with the steroid-dexamethasone, methotrexate, ifosfamide, l-asparaginase, and etoposide regimen. Altogether, our findings show that PTPRK underexpression leads to STAT3 activation and contributes to NKTCL pathogenesis.
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5
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Abstract
It has long been thought that PTPs (protein tyrosine phosphatases) normally function as tumour suppressors. Recent high-throughput mutational analysis identified loss-of-function mutations in six PTPs in human colon cancers, providing critical cancer genetics evidence that PTPs can act as tumour suppressor genes. PTPRT (protein tyrosine phosphatase receptor-T), a member of the family of type IIB receptor-like PTPs, is the most frequently mutated PTP among them. Consistent with the notion that PTPRT is a tumour suppressor, PTPRT knockout mice are hypersensitive to AOM (azoxymethane)-induced colon cancer. The present review focuses on the physiological and pathological functions of PTPRT as well as the cellular pathways regulated by this phosphatase.
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6
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Easty DJ, Gray SG, O'Byrne KJ, O'Donnell D, Bennett DC. Receptor tyrosine kinases and their activation in melanoma. Pigment Cell Melanoma Res 2011; 24:446-61. [PMID: 21320293 DOI: 10.1111/j.1755-148x.2011.00836.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Receptor tyrosine kinases (RTKs) and their downstream signalling pathways have long been hypothesized to play key roles in melanoma development. A decade ago, evidence was derived largely from animal models, RTK expression studies and detection of activated RAS isoforms in a small fraction of melanomas. Predictions that overexpression of specific RTKs implied increased kinase activity and that some RTKs would show activating mutations in melanoma were largely untested. However, technological advances including rapid gene sequencing, siRNA methods and phospho-RTK arrays now give a more complete picture. Mutated forms of RTK genes including KIT, ERBB4, the EPH and FGFR families and others are known in melanoma. Additional over- or underexpressed RTKs and also protein tyrosine phosphatases (PTPs) have been reported, and activities measured. Complex interactions between RTKs and PTPs are implicated in the abnormal signalling driving aberrant growth and survival in malignant melanocytes, and indeed in normal melanocytic signalling including the response to ultraviolet radiation. Kinases are considered druggable targets, so characterization of global RTK activity in melanoma should assist the rational development of tyrosine kinase inhibitors for clinical use.
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Affiliation(s)
- David J Easty
- Department of Oncology, St James's Hospital, Dublin, Ireland Division of Biomedical Sciences, St George's, University of London, London, UK.
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7
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Abstract
Members of the protein tyrosine phosphatase (Ptp) family dephosphorylate target proteins and counter the activities of protein tyrosine kinases that are involved in cellular phosphorylation and signalling. As such, certain PTPs might be tumour suppressors. Indeed, PTPs play an important part in the inhibition or control of growth, but accumulating evidence indicates that some PTPs may exert oncogenic functions. Recent large-scale genetic analyses of various human tumours have highlighted the relevance of PTPs either as putative tumour suppressors or as candidate oncoproteins. Progress in understanding the regulation and function of PTPs has provided insights into which PTPs might be potential therapeutic targets in human cancer.
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Affiliation(s)
- Sofi G Julien
- Goodman Cancer Research Centre, Department of Biochemistry, McGill University, Montreal, Quebec, Canada
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8
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Lynch RM, Naswa S, Rogers GL, Kania SA, Das S, Chesler EJ, Saxton AM, Langston MA, Voy BH. Identifying genetic loci and spleen gene coexpression networks underlying immunophenotypes in BXD recombinant inbred mice. Physiol Genomics 2010; 41:244-53. [PMID: 20179155 PMCID: PMC4073992 DOI: 10.1152/physiolgenomics.00020.2010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2010] [Accepted: 02/22/2010] [Indexed: 01/20/2023] Open
Abstract
The immune system plays a pivotal role in the susceptibility to and progression of a variety of diseases. Due to a strong genetic basis, heritable differences in immune function may contribute to differential disease susceptibility between individuals. Genetic reference populations, such as the BXD (C57BL/6J × DBA/2J) panel of recombinant inbred (RI) mouse strains, provide unique models through which to integrate baseline phenotypes in healthy individuals with heritable risk for disease because of the ability to combine data collected from these populations across both multiple studies and time. We performed basic immunophenotyping (e.g., percentage of circulating B and T lymphocytes and CD4(+) and CD8(+) T cell subpopulations) in peripheral blood of healthy mice from 41 BXD RI strains to define the immunophenotypic variation in this strain panel and to characterize the genetic architecture that underlies these traits. Significant QTL models that explained the majority (50-77%) of phenotypic variance were derived for each trait and for the T:B cell and CD4(+):CD8(+) ratios. Combining QTL mapping with spleen gene expression data uncovered two quantitative trait transcripts, Ptprk and Acp1, as candidates for heritable differences in the relative abundance of helper and cytotoxic T cells. These data will be valuable in extracting genetic correlates of the immune system in the BXD panel. In addition, they will be a useful resource for prospective, phenotype-driven model selection to test hypotheses about differential disease or environmental susceptibility between individuals with baseline differences in the composition of the immune system.
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Affiliation(s)
- Rachel M Lynch
- Systems Genetics Group, Oak Ridge National Laboratory, Oak Ridge
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9
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Novellino L, De Filippo A, Deho P, Perrone F, Pilotti S, Parmiani G, Castelli C. PTPRK negatively regulates transcriptional activity of wild type and mutated oncogenic beta-catenin and affects membrane distribution of beta-catenin/E-cadherin complexes in cancer cells. Cell Signal 2008; 20:872-83. [PMID: 18276111 DOI: 10.1016/j.cellsig.2007.12.024] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2007] [Revised: 12/20/2007] [Accepted: 12/21/2007] [Indexed: 12/01/2022]
Abstract
Previous reports showed that receptor-type protein-tyrosine phosphatase PTPRK co-localizes with beta-catenin at adherens junctions, and in vitro experiments suggested that beta-catenin could be substrate of PTPRK-mediated phosphatase activity. beta-catenin is a molecule endowed with a dual function being involved both in cell adhesion and in Wnt signaling pathway. Here we provide evidence for the role of PTPRK in negatively regulating the beta-catenin transcriptional activity by modulating its intracellular and membrane distribution. Expression of PTPRK protein in HEK293 cells and in PTPRK-null melanoma cell lines, one of which harbors a mutated oncogenic beta-catenin, impairs nuclear accumulation of wild type and oncogenic forms of beta-catenin, limits cytosolic levels of tyrosine-phosphorylated beta-catenin, and leads to re-localization of E-cadherin/beta-catenin complexes in ordered membrane phase along cell-cell contacts. This re-modulation of beta-catenin cellular distribution results in the inhibition of cyclin D1 and c-myc protein expression, whose genes are targets of beta-catenin. Tumor cells upon re-expression of PTPRK have a reduced proliferative and migration capacity. Moreover we show that PTPRK is also active in negatively regulating the transactivating function of beta-catenin in normal melanocytes as confirmed by experiments with silenced PTPRK by specific siRNA. Our data show that PTPRK influences transactivating activity of beta-catenin in non-tumoral and neoplastic cells by regulating the balance between signaling and adhesive beta-catenin, thus providing biochemical basis for the hypothesis of PTPRK as a tumor suppressor gene.
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Affiliation(s)
- Luisa Novellino
- Unit of Immunotherapy of Human Tumors, Department of Experimental Oncology, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy
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10
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Affiliation(s)
- Tasneem Motiwala
- Department of Molecular and Cellular Biochemistry, The Ohio State University, College of Medicine, Columbus, Ohio 43210, USA
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11
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Jacob ST, Motiwala T. Epigenetic regulation of protein tyrosine phosphatases: potential molecular targets for cancer therapy. Cancer Gene Ther 2005; 12:665-72. [PMID: 15803146 PMCID: PMC3028596 DOI: 10.1038/sj.cgt.7700828] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Promoter methylation-mediated silencing is a hallmark of many established tumor suppressor genes. This review focuses on the methylation and suppression of a receptor-type tyrosine phosphatase gene, PTPRO, in a variety of solid and liquid tumors. In addition, PTPRO exhibits many other characteristics of a bona fide tumor suppressor. Reactivation of genes silenced by methylation using inhibitors of DNA methyltransferases and histone deacetylases, and the potential application of PTPRO as a molecular target for cancer therapy have been discussed.
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Affiliation(s)
- Samson T Jacob
- Department of Molecular and Cellular Biochemistry, The Ohio State University, College of Medicine, Columbus, OH 43210, USA.
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12
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Wang SE, Wu FY, Shin I, Qu S, Arteaga CL. Transforming growth factor {beta} (TGF-{beta})-Smad target gene protein tyrosine phosphatase receptor type kappa is required for TGF-{beta} function. Mol Cell Biol 2005; 25:4703-15. [PMID: 15899872 PMCID: PMC1140650 DOI: 10.1128/mcb.25.11.4703-4715.2005] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Transforming growth factor beta (TGF-beta) inhibits proliferation and promotes cell migration. In TGF-beta-treated MCF10A mammary epithelial cells overexpressing HER2 and by chromatin immunoprecipitation, we identified novel Smad targets including protein tyrosine phosphatase receptor type kappa (PTPRK). TGF-beta up-regulated PTPRK mRNA and RPTPkappa (receptor type protein tyrosine phosphatase kappa, the protein product encoded by the PTPRK gene) protein in tumor and nontumor mammary cells; HER2 overexpression down-regulated its expression. RNA interference (RNAi) of PTPRK accelerated cell cycle progression, enhanced response to epidermal growth factor (EGF), and abrogated TGF-beta-mediated antimitogenesis. Endogenous RPTPkappa associated with EGF receptor and HER2, resulting in suppression of basal and ErbB ligand-induced proliferation and receptor phosphorylation. In MCF10A/HER2 cells, TGF-beta enhanced cell motility, FAK phosphorylation, F-actin assembly, and focal adhesion formation and inhibited RhoA activity. These responses were abolished when RPTPkappa was eliminated by RNA interference (RNAi). In cells expressing RPTPkappa RNAi, phosphorylation of Src at Tyr527 was increased and (activating) phosphorylation of Src at Tyr416 was reduced. These data suggest that (i) RPTPkappa positively regulates Src; (ii) HER2 signaling and TGF-beta-induced RPTPkappa converge at Src, providing an adequate input for activation of FAK and increased cell motility and adhesion; and (iii) RPTPkappa is required for both the antiproliferative and the promigratory effects of TGF-beta.
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Affiliation(s)
- Shizhen Emily Wang
- Division of Oncology, Department of Cancer Biology, Vanderbilt University School of Medicine, 2220 Pierce Ave., 777 PRB, Nashville, TN 37232-6307, USA
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13
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Novellino L, Renkvist N, Rini F, Mazzocchi A, Rivoltini L, Greco A, Deho P, Squarcina P, Robbins PF, Parmiani G, Castelli C. Identification of a mutated receptor-like protein tyrosine phosphatase kappa as a novel, class II HLA-restricted melanoma antigen. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2003; 170:6363-70. [PMID: 12794170 DOI: 10.4049/jimmunol.170.12.6363] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Recent studies increasingly point to a pivotal role of CD4(+) T cells in human anti-tumor immune response. Here we show that lymphocytes purified from a tumor-infiltrated lymph node of a melanoma patient that had remained disease free for 10 years after surgical resection of a lymph node metastasis comprised oligoclonal class II HLA-restricted CD4(+) T cells recognizing the autologous tumor cells in vitro. In fact, the CD4(+) T cell clones isolated from these lymphocytes displayed a tumor-specific, cytotoxic activity in addition to a Th1-like cytokine profile. By a genetic approach, a peptide derived from a mutated receptor-like protein tyrosine phosphatase kappa was identified as a novel HLA-DR10-restricted epitope for all the melanoma-specific CD4(+) T cell clones. The immunogenic peptide was shown to contain the mutated residue that was crucial for T cell recognition and activation. Moreover, a systemic immunity against the mutated peptide was detectable in the patient's peripheral blood T lymphocytes obtained during the disease-free period of follow-up. These findings further support the relevance of CD4(+) T cells directed against mutated epitopes in tumor immunity and provide the rationale for a possible usage of mutated, tumor-specific Ags for immunotherapy of human cancer.
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MESH Headings
- Amino Acid Sequence
- Antigen Presentation/genetics
- Antigens, Differentiation, B-Lymphocyte/immunology
- Antigens, Differentiation, B-Lymphocyte/metabolism
- Antigens, Neoplasm/biosynthesis
- Antigens, Neoplasm/genetics
- Antigens, Neoplasm/immunology
- Antigens, Neoplasm/isolation & purification
- CD4-Positive T-Lymphocytes/immunology
- CD4-Positive T-Lymphocytes/pathology
- Cell Line, Transformed
- Clone Cells
- Epitopes, T-Lymphocyte/genetics
- Epitopes, T-Lymphocyte/immunology
- Epitopes, T-Lymphocyte/metabolism
- HLA-DR Antigens/immunology
- HLA-DR Antigens/metabolism
- Histocompatibility Antigens Class II/immunology
- Histocompatibility Antigens Class II/metabolism
- Humans
- Lymphocytes, Tumor-Infiltrating/immunology
- Lymphocytes, Tumor-Infiltrating/pathology
- Melanoma/genetics
- Melanoma/immunology
- Melanoma/pathology
- Molecular Sequence Data
- Mutation
- Peptide Fragments/immunology
- Peptide Fragments/metabolism
- Protein Tyrosine Phosphatases/biosynthesis
- Protein Tyrosine Phosphatases/genetics
- Protein Tyrosine Phosphatases/immunology
- Protein Tyrosine Phosphatases/isolation & purification
- RNA, Messenger/biosynthesis
- Receptor-Like Protein Tyrosine Phosphatases, Class 2
- Transfection
- Tumor Cells, Cultured
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Affiliation(s)
- Luisa Novellino
- Unit of Immunotherapy of Human Tumors and Unit of Molecular Mechanisms of Tumor Growth and Progression, Istituto Nazionale per lo Studio e la Cura dei Tumori, Milan, Italy
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14
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McArdle L, Rafferty M, Maelandsmo GM, Bergin O, Farr CJ, Dervan PA, O'Loughlin S, Herlyn M, Easty DJ. Protein tyrosine phosphatase genes downregulated in melanoma. J Invest Dermatol 2001; 117:1255-60. [PMID: 11710941 DOI: 10.1046/j.0022-202x.2001.01534.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Phospho-tyrosine levels are increased in melanoma, apparently consistent with reports of elevated protein tyrosine kinase activity. Some protein tyrosine kinases are encoded by oncogenes and have been implicated in melanoma genesis. Decreased protein tyrosine phosphatase activity may also increase phospho-tyrosine. Protein tyrosine phosphatase genes are candidate tumor suppressors and loss of expression may contribute to melanoma genesis. Here we survey protein tyrosine phosphatase expression in pigment cells. Protein tyrosine phosphatase genes were cloned by reverse transcriptase polymerase chain reaction using degenerate primers based upon conserved sequences within the phosphatase catalytic domain. Reaction products were cloned and sequenced: 118 and 113 partial protein tyrosine phosphatase products were isolated from normal melanocytes and melanoma cells, respectively. Northern blotting analysis was used to study expression of 15 protein tyrosine phosphatase genes. Expression of PTP-kappa and PTP-pi was absent or downregulated in more than 20% of melanoma cell lines and in some unmanipulated melanoma biopsies. These closely related enzymes are members of the 2B receptor protein tyrosine phosphatase family previously implicated in contact inhibition. Loss of protein tyrosine phosphatase expression may contribute to the abnormal tyrosine phosphorylation seen in melanoma; these genes are candidate tumor suppressors.
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Affiliation(s)
- L McArdle
- Department of Pathology, Conway Institute, University College Dublin, Belfield, Dublin, Ireland
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Barghorn A, Speel EJ, Farspour B, Saremaslani P, Schmid S, Perren A, Roth J, Heitz PU, Komminoth P. Putative tumor suppressor loci at 6q22 and 6q23-q24 are involved in the malignant progression of sporadic endocrine pancreatic tumors. THE AMERICAN JOURNAL OF PATHOLOGY 2001; 158:1903-11. [PMID: 11395364 PMCID: PMC1891980 DOI: 10.1016/s0002-9440(10)64658-5] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Our previous comparative genomic hybridization study on sporadic endocrine pancreatic tumors (EPTs) revealed frequent losses on chromosomes 11q, 3p, and 6q. The aim of this study was to evaluate the importance of 6q losses in the oncogenesis of sporadic EPTs and to narrow down the smallest regions of allelic deletion. A multimodal approach combining polymerase chain reaction-based allelotyping, double-target fluorescence in situ hybridization, and comparative genomic hybridization was used in a collection of 109 sporadic EPTs from 93 patients. Nine polymorphic microsatellite markers (6q13 to 6q25-q27) were investigated, demonstrating a loss of heterozygosity (LOH) in 62.2% of the patients. A LOH was significantly more common in tumors >2 cm in diameter than below this threshold as well as in malignant than in benign tumors. We were able to narrow down the smallest regions of allelic deletion at 6q22.1 (D6S262) and 6q23-q24 (D6S310-UTRN) with LOH-frequencies of 50.0% and 41.2 to 56.3%, respectively. Several promising tumor suppressor candidates are located in these regions. Additional fluorescence in situ hybridization analysis on 46 EPTs using three locus-specific probes (6q21, 6q22, and 6q27) as well as a centromere 6-specific probe revealed complete loss of chromosome 6 especially in metastatic disease. We conclude that the two hot spots found on 6q may harbor putative tumor suppressor genes involved not only in the oncogenesis but maybe also in the malignant and metastatic progression of sporadic EPTs.
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Affiliation(s)
- A Barghorn
- Department of Pathology, University of Zürich, Zürich, Switzerland. University of Maastricht, Maastricht, The Netherlands.
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