Download or read book Protein Tyrosine Phosphatases in Human Breast Cancer Cell written by Universitat de València. Facultat de Ciències Biològiques and published by . This book was released on 2011 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Characterization of Protein Tyrosine Phosphatases in Human Breast Epithelial Cells Neoplastically Transformed by the NEU Oncogene written by Yifan Zhai and published by . This book was released on 1993 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Protein Tyrosine Phosphatases in Cancer written by Benjamin G. Neel and published by Springer. This book was released on 2016-08-05 with total page 362 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book aims to bridge the gap in understanding how protein-tyrosine phosphatases (PTPs), which carry out the reverse reaction of tyrosine phosphorylation, feature in cancer cell biology. The expertly authored chapters will first review the general features of the PTP superfamily, including their overall structure and enzymological properties; use selected examples of individual PTP superfamily members, to illustrate emerging data on the role of PTPs in cancer; and will review the current status of PTP-based drug development efforts. Protein Tyrosine Phosphatases in Cancer,from renowned researchers Benjamin Neel and Nicholas Tonks, is invaluable reading for researchers in oncology, stem cell signaling,and biochemistry.
Download or read book The Role of Protein Tyrosine Phosphatase Gamma in Human Breast Carcinogenesis written by Sherry T. Shu and published by . This book was released on 2005 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Reduced expression of protein tyrosine phosphatase gamma (PTPG) has been shown in breast cancer cell lines and cancerous tissue. PTPG over-expression in breast cancer cell line MCF-7 leads to the inhibition of cell proliferation and anchorage- independent growth. To further investigate the anti-carcinogenic abilities of PTPG in vivo, athymic nude mice were implanted with MCF-7 cells, which were stably transfected with PTPG cDNA (M7-PTPG) or empty vectors (M7-PCR). Tumor formation was significantly lower at the M7-PTPG cells implanted sites (10%) compared to sites where M7-PCR cells were implanted (100%), indicating that tumor formation was inhibited by the effect of PTPG in vivo. To explore the signaling pathway that PTPG is involved, breast cancer-related signaling cDNA array assays were performed. Seventy genes showed at least a 1.5 fold of expression difference in M7-PTPG cells compared to M7- PCR cells. The increase of the levels of p21(cip) and p27(kip) in M7-PTPG cells was confirmed by Western blot analyses. M7-PTPG cells also showed delayed re-entry into the cell cycle after the cells were released from G0/G1 cell cycle arrest, accompanied by lower phosphorylation levels of ERK1/2, compared to the control cells. Moreover, there was an aberrant methylation pattern in the PTPG promoter region of the breast cancer cell lines and patient's cancerous tissue. PTPG expression in SkBr3 cells can be recovered by treating with deoxy-5-azacytidine (DAC) and trichostatin A (TSA). Our results indicate that PTPG inhibits breast tumor promotion in vivo, presumably through cell cycle arrest by the up-regulated p21(cip) and p27(kip) proteins; and DNA methylation is a possible mechanism that leads to PTPG silencing in breast cancer cells. The results obtained from this study suggest that PTPG plays important role in breast carcinogenesis and may serve as a breast cancer therapeutic target.
Download or read book Molecular Biology of Prostate Cancer written by Manfred Wirth and published by Walter de Gruyter. This book was released on 2013-05-22 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Childs Bernard 1910 written by and published by . This book was released on with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The folder may include clippings, announcements, small exhibition catalogs, and other ephemeral items.
Download or read book Studies of Variant SHP 1 Protein Tyrosine Phosphatases in Human Epithelial Cells microform written by Simmy C. T. (Simmy Chui Ting) Wan and published by Library and Archives Canada = Bibliothèque et Archives Canada. This book was released on 2004 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt: The SH2 domain containing protein tyrosine phosphatase SHP-1 negatively regulates hematopoietic cell growth; however, its function in epithelial cells remains unclear. SHP-1 is auto-inhibited by an intramolecular interaction between its N-SH2 domain and C-terminus. Using human epithelial cancer cell lines we detected alternatively-spliced in-frame SHP-1 transcripts that utilize either promoter 1 or 2, have a partial (exon 3) or complete (exons 3 & 4) deletion of the N-SH2 domain, and demonstrate intron 2 retention (non-coding). We showed that exon 3 deleted SHP-1 protein is difficult to express and may have a shortened half-life, and SHP-1 lacking the entire N-SH2 domain has increased phosphatase activity. Both exon(s) deleted SHP-1 exhibits unusual protein-binding patterns. Multiple SHP-1 proteins with sizes corresponding to those predicted by alternate transcripts were detected in SK-BR-3 human breast cancer cells. With unregulated activities and differential protein-binding patterns, variant SHP-1 may contribute to epithelial tumorigenesis by modulating normal signaling pathways.
Download or read book Involvement of the Tyrosine Phosphatase SHP 1 in the Development of Breast Cancer written by and published by . This book was released on 2001 with total page 43 pages. Available in PDF, EPUB and Kindle. Book excerpt: Purpose: To test the working hypothesis that SHP-1 is essential for controlling growth and differentiation of mammary epithelial cells and that its dysregulation contributes to the development of breast cancer. Scope: To biochemically and functionally characterize SHP-1 in human breast cancer cell lines and to define its biological function in normal epithelial cells. Major Findings: We have shown that SHP-1 localizes to the lipid raft. Moreover, our data indicate a functional difference between rafts- and non-rafts-associated fractions of SHP-1. While most of these studies have been performed in T cells and primary thymocytes, in initial experiments using human breast cancer cells, we have observed that limited amounts of SHP-1 localize to lipid rafts before and after EGF stimulation. In addition, we have obtained additional data showing that a transgenic mouse expressing SHP-1 under its own hematopoietic promoter is able to partially rescue the Motheaten phenotype.
Download or read book Cell Adhesion Linked Protein Tyrosine Phosphatases and Breast Cancer Metastasis written by and published by . This book was released on 2004 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: 21 "CLASSICAL" PROTEIN TYROSINE PHOSPHATASES (PTPs) were identified in human mammary epithelial cell (MEC) lines. Degenerate RT-PCR followed by restriction fragment differential display (RFDD) and specific RT-PCR were used to assess expression in the continuous HMT-3522 cell series that includes both non-malignant Si and tumorigenic T4-2 cells in monolayer and during normal and dysregulated morphogenesis in EHS-ECM (Matrigel). PTP expression was generally higher in tumorigenic T4-2 cells and unchanged by disorganized growth in Matigel. in contrast, coordination of expression was suggested by the transient upregulation (relative to monolayer cultures) of a number of PTPs during acinar morphogenesis of non-malignant Si. The kinetics of downregulation for some suggested that growth arrest may be the main regulatory input. Others however, downregulate with more rapid kinetics before significant growth arrest suggesting different regulatory inputs. Feedback from of cell-cell adherens junctions (AJ) may be one such input as ectopic expression of a dominant negative E-cadherin construct that blocks AJ formation delayed but did not prevent downregulation of selected PTPs. Modest upregulation of actin cytoskeleton regulating PTPs in response to decreases in substrate compliancy occur when normal MCF10A were plated on (^1 order of magnitude) softer (tissue-like) Matrigel coupled polyacrylamide gels suggesting that these PTPs may be responding to, or mediating corresponding actin cytoskeletal reaorganization. PTPN12 is a cytoplasmic PTP highly expressed in MECs that localizes transiently to actin polymerizing zones including lamellopodial leading edges and the metaphase mitotic spindle and plasma membrane. Stable downregulation of PTPN12 by retroviral mediated shRNAi resulted in derangements of the actin cytoskeleton in MCF10A cells. These cells grew more rapidly and formed larger but normally polarized acini in Matrigel.
Download or read book Protein Tyrosine Phosphatases written by Lalima G. Ahuja and published by Walter de Gruyter GmbH & Co KG. This book was released on 2018-10-08 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt: Protein tyrosine phosphatases remove phosphates from the phosphotyrosine residues of target proteins and reverse the action of various protein tyrosine kinases. This essential interplay between the opposing actions of protein tyrosine phosphatases and protein tyrosine kinases forms the basis of signaling networks that underlie the cellular workings of human physiology. Initially passed-off as housekeeping genes; these proteins were only acknowledged to maintain a steady background of phosphotyrosine levels in the cell. However, recent progress in studying their role in embryonic development and human disease has established their importance as regulators of signal regulation. Convincing evidence shows the role of mutations in these proteins to cause and/or intensify the severity of various diseases including metabolic and neurological disorders and also cancer. Protein tyrosine phosphatases have slowly, yet convincingly become crucial targets for therapeutic intervention of various human pathophysiologies. This book describes these signaling enzymes using the molecular details of their structure and mechanistic function. Various subtypes of cysteine-based Class I, II, III and the Haloacid dehalogenase related Class IV protein tyrosine phosphatases have been illustrated and explained. The superfamily of proteins is also described vis-a-vis its complimentary protein phosphoserine/phosphoserine phosphatases. Membrane bound receptor forms and the cytosolic non-receptor protein tyrosine phosphatases have been described for their biological function. This book serves as a reference for any reader looking to understand the sequence features, structural elements, molecular mechanism and cellular function of this superfamily of signaling enzymes.
Download or read book Modulation of Protein Tyrosine Phosphatase PTP gamma Signaling by MicroRNA and Ligand Binding written by Shu-Hong Lin and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Protein Tyrosine Phosphatase [gamma] (PTP[gamma], encoded by PTPRG gene) has been shown to be an estrogen-regulated tumor suppressor in breast cancers. Our current studies focus on mechanisms which are influential in PTP[gamma] in both breast cancer cell line and primary cultured breast cancer cells. In search for the differences in micorRNA (miRNA) profiles among primary cultured human breast cancer cell (CEC) and adjacent normal cell (NAE), we found 24 up-regulated and 1 down-regulated miRNA in CEC. Among the up-regulated miRNAs, miR-141 is predicted to target PTPRG based on sequence and transient transfection of the precursor for miR-141 (pre-miR-141) in triple negative human breast cancer cell line, MDA-MB-231 cells successfully resulted in the down-regulation of PTPRG. Further experiments with 14 pairs of CEC and NAE from patients revealed a moderate negative association (Kendall's [tau] = -0.61) in NAE but not CEC. PTP[gamma] belongs to the receptor type phosphatase family, yet its ligand has not been reported until 2010. Members of contactin (CNTN) family, including CNTN3, 4, 5 and 6, were found to bind PTP[gamma]. However, it is still unclear whether CNTN binding is stimulatory or inhibitory to PTP[gamma] activity. Among the four possible ligands, only CNTN3 was found to be present in normal breast cells. In order to evaluate the impact of CNTN3 binding on PTP[gamma] signaling, we used genes regulated by PTP[gamma] as an indicator. Compared with PTPRG expression level, CNTN3/PTPRG ratio has been found to be equally and even better associated with the expression of downstream genes in CEC and NAE in an opposite direction. Such difference in the direction of association has suggested an inhibitory role for CNTN3 binding in terms of PTP[gamma] signaling.
Download or read book Protein Tyrosine Phosphatases written by Damien Thévenin and published by Springer Nature. This book was released on 2024-01-27 with total page 321 pages. Available in PDF, EPUB and Kindle. Book excerpt: This second edition volume expands on the previous edition with discussions on the latest advancements in protein tyrosine phosphatases (PTP) research used to investigate these essential enzymes and new inhibitors. The new techniques covered in the chapters of this book include studying enzymes in vitro, in cells, and in animal models through proteomics, genomics, and structural biology. Furthermore, new advances in pharmacology and drug design have contributed to the developing novel therapeutics that target PTPs. Written in the highly successful Methods in Molecular Biology series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and tips on troubleshooting and avoiding known pitfalls. Cutting-edge and comprehensive, Protein Tyrosine Phosphatases: Methods and Protocols, Second Edition is a valuable resource for both experienced and novel researchers in this field, and will lead to discoveries and accelerated progress in the field of PTP, signal transduction, and drug development.
Download or read book The Role of RPTP Alpha Like Protein Tyrosine Phosphatases in Mammary Tumorigenesis written by and published by . This book was released on 1999 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Tyrosine phosphorylation is controlled by a balance of tyrosine kinases (PTKs) and protein tyrosine phosphatases (PTPs). Whereas the contribution of PTKs to breast tumorigenesis is the subject of intense scrutiny, the potential role of PTPs is poorly known. RPTP alpha is implicated in the activation of Src family kinases, and regulation of integrin signaling, cell adhesion, and growth factor responsiveness. To explore its potential contribution to human neoplasia, we surveyed RPTP alpha protein levels in primary human breast cancer. We found RPTPa levels to vary widely among tumors, with 29% of cases manifesting significant overexpression. High RPTP alpha protein levels correlated significantly with low tumor grade and positive estrogen receptor status. Expression of RPTPC alpha in breast carcinoma cells led to growth inhibition, associated with increased accumulation in G(0) and G(1), and delayed tumor growth and metastasis. To our knowledge, this is the first example of a study correlating expression level of a specific bona fide PTP with neoplastic disease status in humans.
Download or read book Role of the Protein Tyrosine Phosphatase DEP 1 in Src Activation and the Mediation of Biological Cell Functions of Endothelial and Breast Cancer Cells written by Kathleen Spring and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Adhesion Linked Protein Tyrosine Phosphatases Morphogenesis and Breast Cancer Progression written by and published by . This book was released on 2006 with total page 21 pages. Available in PDF, EPUB and Kindle. Book excerpt: Stromal-epithelial interactions regulate breast cell fate via integrin-growth factor receptor (GFR) interactions that activate tyrosine kinases that are tempered by protein tyrosine phosphatases (PTP). Using a series of molecular screening approaches we profiled PTP expression in normal transformed and phenotypically-reverted breast tissue and identified the Band 4.1 PTPs MEGI and D1 as candidate PTP metastasis suppressors. Our studies have implicated two Band 4.1 PTPs MEGI and D1 as important regulators of adhesion-dependent mammary morphogenesis that are consistently altered in tumors by aberrant tumor-generated mechanical force. Specifically we implicated PTP MEGI as a key regulator of adherens junction assembly/integrity and found that matrix force and tumor-generated contractility chronically increase PTP expression. Importantly ectopic elevated expression of MEGI in nonmalignant MECs enhanced their integrin-dependent cell adhesion disrupted tissue polarity and altered cell growth and survival. Studies are in progress to identify MEGI- specific effector proteins in normal transformed and phenotypically-reverted MECs and to dissect out the mechanism whereby force regulates PTP expression.
Download or read book Encyclopedia of Signaling Molecules written by Sangdun Choi and published by Springer. This book was released on 2017-12-15 with total page 6330 pages. Available in PDF, EPUB and Kindle. Book excerpt: The second edition of this encyclopedia presents over 400 biologically important signaling molecules and the content is built on the core concepts of their functions along with early findings written by some of the world’s foremost experts. The molecules are described by recognized leaders in each molecule. The interactions of these single molecules in signal transduction networks will also be explored. This encyclopedia marks a new era in overview of current cellular signaling molecules for the specialist and the interested non-specialist alike. Currently, there are more than 30,000 genes in human genome. However, not all the proteins encoded by these genes work equally in order to maintain homeostasis. Understanding the important signaling molecules as completely as possible will significantly improve our research-based teaching and scientific capabilities.
Download or read book Protein Tyrosine Phosphatases in Breast Cancer written by Mairin Rafferty and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
