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Jeong BY, Cho KH, Yoon SH, Park CG, Park HW, Lee HY. Discoidin Domain Receptor 2 Mediates Lysophosphatidic Acid-Induced Ovarian Cancer Aggressiveness. Int J Mol Sci 2021; 22:ijms22105374. [PMID: 34065317 PMCID: PMC8160857 DOI: 10.3390/ijms22105374] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 05/14/2021] [Accepted: 05/17/2021] [Indexed: 01/24/2023] Open
Abstract
Lysophosphatidic acid (LPA), a bioactive lipid produced extracellularly by autotaxin (ATX), has been known to induce various pathophysiological events, including cancer cell invasion and metastasis. Discoidin domain receptor 2 (DDR2) expression is upregulated in ovarian cancer tissues, and is closely associated with poor clinical outcomes in ovarian cancer patients. In the present study, we determined a critical role and signaling cascade for the expression of DDR2 in LPA-induced ovarian cancer cell invasion. We also found ectopic expression of ATX or stimulation of ovarian cancer cells with LPA-induced DDR2 expression. However, the silencing of DDR2 expression significantly inhibited ATX- and LPA-induced ovarian cancer cell invasion. In addition, treatment of the cells with pharmacological inhibitors of phosphoinositide 3-kinase (PI3K), Akt, and mTOR abrogated LPA-induced DDR2 expression. Moreover, we observed that HIF-1α, located downstream of the mTOR, is implicated in LPA-induced DDR2 expression and ovarian cancer cell invasion. Finally, we provide evidence that LPA-induced HIF-1α expression mediates Twist1 expression to upregulate DDR2 expression. Collectively, the present study demonstrates that ATX, and thereby LPA, induces DDR2 expression through the activation of the PI3K/Akt/mTOR/HIF-1α/Twist1 signaling axes, aggravating ovarian cancer cell invasion.
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Affiliation(s)
- Bo Young Jeong
- Department of Pharmacology, College of Medicine, Konyang University, Daejeon 35365, Korea; (B.Y.J.); (K.H.C.); (C.G.P.)
| | - Kyung Hwa Cho
- Department of Pharmacology, College of Medicine, Konyang University, Daejeon 35365, Korea; (B.Y.J.); (K.H.C.); (C.G.P.)
| | - Se-Hee Yoon
- Division of Nephrology and Department of Internal Medicine, College of Medicine, Daejeon 35365, Korea;
| | - Chang Gyo Park
- Department of Pharmacology, College of Medicine, Konyang University, Daejeon 35365, Korea; (B.Y.J.); (K.H.C.); (C.G.P.)
| | - Hwan-Woo Park
- Department of Cell Biology, College of Medicine, Konyang University, Daejeon 35365, Korea;
| | - Hoi Young Lee
- Department of Pharmacology, College of Medicine, Konyang University, Daejeon 35365, Korea; (B.Y.J.); (K.H.C.); (C.G.P.)
- Correspondence: ; Tel.: +82-42-600-8687
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Tang X, Benesch MGK, Brindley DN. Role of the autotaxin-lysophosphatidate axis in the development of resistance to cancer therapy. Biochim Biophys Acta Mol Cell Biol Lipids 2020; 1865:158716. [PMID: 32305571 DOI: 10.1016/j.bbalip.2020.158716] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 03/31/2020] [Accepted: 04/09/2020] [Indexed: 12/17/2022]
Abstract
Autotaxin (ATX) is a secreted enzyme that hydrolyzes lysophosphatidylcholine to produce lysophosphatidate (LPA), which signals through six G-protein coupled receptors (GPCRs). Signaling through LPA is terminated by its degradation by a family of three lipid phosphate phosphatases (LPPs). LPP1 also attenuates signaling downstream of the activation of LPA receptors and some other GPCRs. The ATX-LPA axis mediates a plethora of activities such as cell proliferation, survival, migration, angiogenesis and inflammation, which perform an important role in facilitating wound healing. This wound healing response is hijacked by cancers where there is decreased expression of LPP1 and LPP3 and increased expression of ATX. This maladaptive regulation of LPA signaling also causes chronic inflammation, which has been recognized as one of the hallmarks in cancer. The increased LPA signaling promotes cell survival and migration and attenuates apoptosis, which stimulates tumor growth and metastasis. The wound healing functions of increased LPA signaling also protect cancer cells from effects of chemotherapy and radiotherapy. In this review, we will summarize knowledge of the ATX-LPA axis and its role in the development of resistance to chemotherapy and radiotherapy. We will also offer insights for developing strategies of targeting ATX-LPA axis as a novel part of cancer treatment. This article is part of a Special Issue entitled Lysophospholipids and their receptors: New data and new insights into their function edited by Susan Smyth, Viswanathan Natarajan and Colleen McMullen.
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Affiliation(s)
- Xiaoyun Tang
- Department of Biochemistry, University of Alberta, Edmonton T6G 2S2, Canada; Cancer Research Institute of Northern Alberta, University of Alberta, Edmonton T6G 2S2, Canada
| | - Matthew G K Benesch
- Department of Biochemistry, University of Alberta, Edmonton T6G 2S2, Canada; Cancer Research Institute of Northern Alberta, University of Alberta, Edmonton T6G 2S2, Canada; Discipline of Surgery, Faculty of Medicine, Memorial University of Newfoundland, St. John's, Newfoundland and Labrador A1B 3V6, Canada
| | - David N Brindley
- Department of Biochemistry, University of Alberta, Edmonton T6G 2S2, Canada; Cancer Research Institute of Northern Alberta, University of Alberta, Edmonton T6G 2S2, Canada.
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Federico L, Jeong KJ, Vellano CP, Mills GB. Autotaxin, a lysophospholipase D with pleomorphic effects in oncogenesis and cancer progression. J Lipid Res 2016; 57:25-35. [PMID: 25977291 PMCID: PMC4689343 DOI: 10.1194/jlr.r060020] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Revised: 05/07/2015] [Indexed: 12/18/2022] Open
Abstract
The ectonucleotide pyrophosphatase/phosphodiesterase type 2, more commonly known as autotaxin (ATX), is an ecto-lysophospholipase D encoded by the human ENNP2 gene. ATX is expressed in multiple tissues and participates in numerous key physiologic and pathologic processes, including neural development, obesity, inflammation, and oncogenesis, through the generation of the bioactive lipid, lysophosphatidic acid. Overwhelming evidence indicates that altered ATX activity leads to oncogenesis and cancer progression through the modulation of multiple hallmarks of cancer pathobiology. Here, we review the structural and catalytic characteristics of the ectoenzyme, how its expression and maturation processes are regulated, and how the systemic integration of its pleomorphic effects on cells and tissues may contribute to cancer initiation, progression, and therapy. Additionally, the up-to-date spectrum of the most frequent ATX genomic alterations from The Cancer Genome Atlas project is reported for a subset of cancers.
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Affiliation(s)
- Lorenzo Federico
- Department of Systems Biology, University of Texas M. D. Anderson Cancer Center, Houston, TX
| | - Kang Jin Jeong
- Department of Systems Biology, University of Texas M. D. Anderson Cancer Center, Houston, TX
| | - Christopher P Vellano
- Department of Systems Biology, University of Texas M. D. Anderson Cancer Center, Houston, TX
| | - Gordon B Mills
- Department of Systems Biology, University of Texas M. D. Anderson Cancer Center, Houston, TX
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4
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Barbayianni E, Kaffe E, Aidinis V, Kokotos G. Autotaxin, a secreted lysophospholipase D, as a promising therapeutic target in chronic inflammation and cancer. Prog Lipid Res 2015; 58:76-96. [DOI: 10.1016/j.plipres.2015.02.001] [Citation(s) in RCA: 91] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Revised: 01/20/2015] [Accepted: 02/12/2015] [Indexed: 02/07/2023]
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5
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Smith KP, Gifford KM, Waitzman JS, Rice SE. Survey of phosphorylation near drug binding sites in the Protein Data Bank (PDB) and their effects. Proteins 2015; 83:25-36. [PMID: 24833420 PMCID: PMC4233198 DOI: 10.1002/prot.24605] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Revised: 04/28/2014] [Accepted: 05/09/2014] [Indexed: 12/21/2022]
Abstract
While it is currently estimated that 40 to 50% of eukaryotic proteins are phosphorylated, little is known about the frequency and local effects of phosphorylation near pharmaceutical inhibitor binding sites. In this study, we investigated how frequently phosphorylation may affect the binding of drug inhibitors to target proteins. We examined the 453 non-redundant structures of soluble mammalian drug target proteins bound to inhibitors currently available in the Protein Data Bank (PDB). We cross-referenced these structures with phosphorylation data available from the PhosphoSitePlus database. Three hundred twenty-two of 453 (71%) of drug targets have evidence of phosphorylation that has been validated by multiple methods or labs. For 132 of 453 (29%) of those, the phosphorylation site is within 12 Å of the small molecule-binding site, where it would likely alter small molecule binding affinity. We propose a framework for distinguishing between drug-phosphorylation site interactions that are likely to alter the efficacy of drugs versus those that are not. In addition we highlight examples of well-established drug targets, such as estrogen receptor alpha, for which phosphorylation may affect drug affinity and clinical efficacy. Our data suggest that phosphorylation may affect drug binding and efficacy for a significant fraction of drug target proteins.
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Affiliation(s)
- Kyle P Smith
- Department of Cell and Molecular Biology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, 60611
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Yung YC, Stoddard NC, Chun J. LPA receptor signaling: pharmacology, physiology, and pathophysiology. J Lipid Res 2014; 55:1192-214. [PMID: 24643338 DOI: 10.1194/jlr.r046458] [Citation(s) in RCA: 517] [Impact Index Per Article: 51.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Indexed: 12/18/2022] Open
Abstract
Lysophosphatidic acid (LPA) is a small ubiquitous lipid found in vertebrate and nonvertebrate organisms that mediates diverse biological actions and demonstrates medicinal relevance. LPA's functional roles are driven by extracellular signaling through at least six 7-transmembrane G protein-coupled receptors. These receptors are named LPA1-6 and signal through numerous effector pathways activated by heterotrimeric G proteins, including Gi/o, G12/13, Gq, and Gs LPA receptor-mediated effects have been described in numerous cell types and model systems, both in vitro and in vivo, through gain- and loss-of-function studies. These studies have revealed physiological and pathophysiological influences on virtually every organ system and developmental stage of an organism. These include the nervous, cardiovascular, reproductive, and pulmonary systems. Disturbances in normal LPA signaling may contribute to a range of diseases, including neurodevelopmental and neuropsychiatric disorders, pain, cardiovascular disease, bone disorders, fibrosis, cancer, infertility, and obesity. These studies underscore the potential of LPA receptor subtypes and related signaling mechanisms to provide novel therapeutic targets.
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Affiliation(s)
- Yun C Yung
- Department of Molecular and Cellular Neuroscience, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA 92037
| | - Nicole C Stoddard
- Department of Molecular and Cellular Neuroscience, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA 92037 Biomedical Sciences Graduate Program, University of California, San Diego School of Medicine, La Jolla, CA 92037
| | - Jerold Chun
- Department of Molecular and Cellular Neuroscience, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA 92037
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Morishige J, Uto Y, Hori H, Satouchi K, Yoshiomoto T, Tokumura A. Lysophosphatidic acid produced by hen egg white lysophospholipase D induces vascular development on extraembryonic membranes. Lipids 2013; 48:251-62. [PMID: 23381130 DOI: 10.1007/s11745-013-3765-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2012] [Accepted: 01/09/2013] [Indexed: 01/23/2023]
Abstract
Lysophosphatidic acid (lysoPtdOH), a lysophospholipid mediator, exerts diverse physiological effects, including angiogenesis, through its specific G-protein-coupled receptors. Previously, we showed that unfertilized hen egg white contains polyunsaturated fatty acid-rich lysoPtdOH and lysophospholipase D (lysoPLD). Here, we examined whether lysoPtdOH was produced by lysoPLD in the presence and absence of a hen fertilized ovum and what the physiological role of lysoPtdOH in hen egg white is. Mass spectrometry showed that fertilized hen egg white contained about 8 μM lysoPtdOH before incubation with an ovum, mainly comprised of 18:1- (12.6 %), 18:2- (37.8 %) and 20:4-molecular species (41.5 %). In an early gestation period, the lysoPtdOH was increased up to 9.6 μM, concomitant with a decrease in the level of polyunsaturated lysophosphatidylcholine (lysoPtdCho). Moreover, lysoPtdOH-degrading activities were found in egg white and the vitelline membrane, showing that these enzymes control lysoPtdOH levels in egg white. In an egg yolk angiogenesis assay, two lysoPtdOH receptor antagonists, Ki16425 and N-palmitoyl serine phosphoric acid (NASP), inhibited blood vessel formation induced by exogenously added 18:1-lysoPtdOH and its precursor lysoPtdCho on the hen yolk sac. Ki16425 and NASP also inhibited blood vessel formation in the chorioallantoic membrane (CAM). Furthermore, the relatively higher levels of LPA₁, LPA₂, LPA₄ and LPA₆ mRNA were present in the yolk sac and CAM. These results suggest that lysoPtdOH produced from lysoPtdCho by the action of lysoPLD in hen egg white is involved in the formation of blood vessel networks through several lysoPtdOH receptors on various extraembryonic membranes, including the yolk sac membrane and CAM.
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Affiliation(s)
- Junichi Morishige
- Department of Pharmaceutical Health Chemistry, Institute of Health Biosciences, University of Tokushima Graduate School, 1-78-1 Shomachi, Tokushima 770-8505, Japan
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Braeuer RR, Zigler M, Kamiya T, Dobroff AS, Huang L, Choi W, McConkey DJ, Shoshan E, Mobley AK, Song R, Raz A, Bar-Eli M. Galectin-3 contributes to melanoma growth and metastasis via regulation of NFAT1 and autotaxin. Cancer Res 2012; 72:5757-66. [PMID: 22986745 DOI: 10.1158/0008-5472.can-12-2424] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Melanoma is the deadliest form of skin cancer in which patients with metastatic disease have a 5-year survival rate of less than 10%. Recently, the overexpression of a β-galactoside binding protein, galectin-3 (LGALS3), has been correlated with metastatic melanoma in patients. We have previously shown that silencing galectin-3 in metastatic melanoma cells reduces tumor growth and metastasis. Gene expression profiling identified the protumorigenic gene autotaxin (ENPP2) to be downregulated after silencing galectin-3. Here we report that galectin-3 regulates autotaxin expression at the transcriptional level by modulating the expression of the transcription factor NFAT1 (NFATC2). Silencing galectin-3 reduced NFAT1 protein expression, which resulted in decreased autotaxin expression and activity. Reexpression of autotaxin in galectin-3 silenced melanoma cells rescues angiogenesis, tumor growth, and metastasis in vivo. Silencing NFAT1 expression in metastatic melanoma cells inhibited tumor growth and metastatic capabilities in vivo. Our data elucidate a previously unidentified mechanism by which galectin-3 regulates autotaxin and assign a novel role for NFAT1 during melanoma progression.
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Affiliation(s)
- Russell R Braeuer
- Department of Cancer Biology and Urology, The University of Texas, MD Anderson Cancer Center, Houston, Texas 77030, USA
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Ahn HJ, Yang H, An BS, Choi KC, Jeung EB. Expression and regulation of Enpp2 in rat uterus during the estrous cycle. J Vet Sci 2012; 12:379-85. [PMID: 22122904 PMCID: PMC3232398 DOI: 10.4142/jvs.2011.12.4.379] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Ectonucleotide pyrophosphatase/phosphodiestrase 2 (Enpp2) isolated from the supernatant of human melanoma cells is a lysophospholipase D that transforms lysophosphatidylcholine into lysophospatidic acid. Although multiple analyses have investigated the function of Enpp2 in the hypothalamus, its role in the uterus during the estrous cycle is not well understood. In the present study, rat uterine Enpp2 was analyzed by RT-PCR, Western blotting, and immunohistochemistry. Quantitative PCR analysis demonstrated that uterine Enpp2 mRNA was decreased during estrus compared to proestrus and diestrus. To determine whether uterine Enpp2 expression is affected by sex steroid hormones, immature rats were treated with 17β-estradiol (E2), progesterone, or both on postnatal days 14 to 16. Interestingly, the expression of Enpp2 mRNA and protein were down-regulated by E2 in the uterus during estrus but not during proestrus or diestrus, suggesting that Enpp2 may play a role in uterine function during estrus. Enpp2 is primarily localized in the stromal cells of the endometrium during proestrus and estrus. During diestrus, Enpp2 was highly expressed in the epithelial cells of the endometrium. Taken together, these results suggest that uterine Enpp2 may be regulated by E2 and plays a role in reproductive functions during female rat development.
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Affiliation(s)
- Hyo-Jin Ahn
- Laboratory of Veterinary Biochemistry and Molecular Biology, College of Veterinary Medicine, Chungbuk National University, Cheongju 361-763, Korea
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Nishimasu H, Ishitani R, Aoki J, Nureki O. A 3D view of autotaxin. Trends Pharmacol Sci 2012; 33:138-45. [DOI: 10.1016/j.tips.2011.12.004] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2011] [Revised: 12/16/2011] [Accepted: 12/23/2011] [Indexed: 12/26/2022]
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Saunders LP, Cao W, Chang WC, Albright RA, Braddock DT, De La Cruz EM. Kinetic analysis of autotaxin reveals substrate-specific catalytic pathways and a mechanism for lysophosphatidic acid distribution. J Biol Chem 2011; 286:30130-41. [PMID: 21719699 PMCID: PMC3191052 DOI: 10.1074/jbc.m111.246884] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2011] [Revised: 06/23/2011] [Indexed: 01/28/2023] Open
Abstract
Autotaxin (ATX) is a secreted lysophospholipase D that hydrolyzes lysophosphatidylcholine (LPC) into lysophosphatidic acid (LPA), initiating signaling cascades leading to cancer metastasis, wound healing, and angiogenesis. Knowledge of the pathway and kinetics of LPA synthesis by ATX is critical for developing quantitative physiological models of LPA signaling. We measured the individual rate constants and pathway of the LPA synthase cycle of ATX using the fluorescent lipid substrates FS-3 and 12-(N-methyl-N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl))-LPC. FS-3 binds rapidly (k(1) ≥500 μm(-1) s(-1)) and is hydrolyzed slowly (k(2) = 0.024 s(-1)). Release of the first hydrolysis product is random and rapid (≥1 s(-1)), whereas release of the second is slow and rate-limiting (0.005-0.007 s(-1)). Substrate binding and hydrolysis are slow and rate-limiting with LPC. Product release is sequential with choline preceding LPA. The catalytic pathway and kinetics depend strongly on the substrate, suggesting that ATX kinetics could vary for the various in vivo substrates. Slow catalysis with LPC reveals the potential for LPA signaling to spread to cells distal to the site of LPC substrate binding by ATX. An ATX mutant in which catalytic threonine at position 210 is replaced with alanine binds substrate weakly, favoring a role for Thr-210 in binding as well as catalysis. FTY720P, the bioactive form of a drug currently used to treat multiple sclerosis, inhibits ATX in an uncompetitive manner and slows the hydrolysis reaction, suggesting that ATX inhibition plays a significant role in lymphocyte immobilization in FTY720P-based therapeutics.
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Affiliation(s)
- Lauren P. Saunders
- From the Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520 and
| | - Wenxiang Cao
- From the Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520 and
| | - William C. Chang
- the Department of Pathology, Yale University School of Medicine, New Haven, Connecticut 06510
| | - Ronald A. Albright
- the Department of Pathology, Yale University School of Medicine, New Haven, Connecticut 06510
| | - Demetrios T. Braddock
- the Department of Pathology, Yale University School of Medicine, New Haven, Connecticut 06510
| | - Enrique M. De La Cruz
- From the Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520 and
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Xia Q, Deng AM, Wu SS, Zheng M. Cholera toxin inhibits human hepatocarcinoma cell proliferation in vitro via suppressing ATX/LPA axis. Acta Pharmacol Sin 2011; 32:1055-62. [PMID: 21765444 DOI: 10.1038/aps.2011.31] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM To investigate the antitumor effect of cholera toxin (CT) in hepatocellular carcinoma (HCC) in vitro and the mechanisms underlying the effect. METHODS Human hepatocellular carcinoma cell lines Hep3B and Huh7, which expressed moderate and high level of autotaxin (ATX), respectively, were used. Cytokine level in the cells was evaluated using ELISA assay, and cell proliferation was investigated using MTT assay. ATX expression was determined using Western blot. ATX/lyso-PLD activity in the conditioned medium was measured using FS-3, a fluorescent lysophosphatidylcholine (LPC) analogue, as substrate. RESULTS Exposure to CT (7.5 and 10 ng/mL) significantly inhibited the cell growth, decreased secretion of proinflammatory cytokine TNF-α and promoted secretion of anti-inflammatory cytokines IL-4 and IL-10. CT at 10 ng/mL markedly suppressed ATX expression in Hep3B and Huh7 cells. Furthermore, ATX and lysophosphatidic acid (LPA) were found to be crucial for growth of the cancer cells. CT could inhibit TNF-α-induced expression and secretion of ATX that led to decreased activity of lysophospholipase D, thus decreasing the conversion of LPC to LPA. CONCLUSION CT inhibits hepatocellular carcinoma cell growth in vitro via regulating the ATX-LPA pathway.
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Nishimasu H, Okudaira S, Hama K, Mihara E, Dohmae N, Inoue A, Ishitani R, Takagi J, Aoki J, Nureki O. Crystal structure of autotaxin and insight into GPCR activation by lipid mediators. Nat Struct Mol Biol 2011; 18:205-12. [PMID: 21240269 DOI: 10.1038/nsmb.1998] [Citation(s) in RCA: 197] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2010] [Accepted: 11/19/2010] [Indexed: 01/08/2023]
Abstract
Autotaxin (ATX, also known as Enpp2) is a secreted lysophospholipase D that hydrolyzes lysophosphatidylcholine to generate lysophosphatidic acid (LPA), a lipid mediator that activates G protein-coupled receptors to evoke various cellular responses. Here, we report the crystal structures of mouse ATX alone and in complex with LPAs with different acyl-chain lengths and saturations. These structures reveal that the multidomain architecture helps to maintain the structural rigidity of the lipid-binding pocket, which accommodates the respective LPA molecules in distinct conformations. They indicate that a loop region in the catalytic domain is a major determinant for the substrate specificity of the Enpp family enzymes. Furthermore, along with biochemical and biological data, these structures suggest that the produced LPAs are delivered from the active site to cognate G protein-coupled receptors through a hydrophobic channel.
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Affiliation(s)
- Hiroshi Nishimasu
- Department of Biophysics and Biochemistry, Graduate School of Science, The University of Tokyo, Tokyo, Japan
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Parrill AL, Baker DL. Autotaxin inhibitors: a perspective on initial medicinal chemistry efforts. Expert Opin Ther Pat 2010; 20:1619-25. [PMID: 21047298 DOI: 10.1517/13543776.2010.533658] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The lysophospholipase D enzyme, autotaxin (ATX), has been linked to numerous human diseases including cancer, neurophatic pain, obesity and Alzheimer's disease. Although the ATX protein was initially purified and characterized in 1992, a link to bioactive lipid metabolism was not made until 2002. In the past decade, metal chelators, lysophospholipid product analogs, and more recently, small non-lipid inhibitors of the enzyme were successfully identified. The majority of these inhibitors have been characterized using recombinant purified ATX in vitro, with very few examples studied in more complex systems. Translation of ATX inhibitors from the hands of medicinal chemists to clinical use will require substantially expanded characterization of ATX inhibitors in vivo.
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Affiliation(s)
- Abby L Parrill
- The University of Memphis, Department of Chemistry, Memphis, TN 38152, USA.
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15
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Immunohistochemical Detection of Autotaxin (ATX)/Lysophospholipase D (lysoPLD) in Submucosal Invasive Colorectal Cancer. J Gastrointest Cancer 2010; 42:204-11. [DOI: 10.1007/s12029-010-9186-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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16
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Biological roles of lysophosphatidic acid signaling through its production by autotaxin. Biochimie 2010; 92:698-706. [PMID: 20417246 DOI: 10.1016/j.biochi.2010.04.015] [Citation(s) in RCA: 128] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2009] [Accepted: 04/19/2010] [Indexed: 12/20/2022]
Abstract
Lysophosphatidic acid (LPA) exhibits a wide variety of biological functions as a bio-active lysophospholipid through G-protein-coupled receptors specific to LPA. Currently at least six LPA receptors are identified, named LPA(1) to LPA(6), while the existence of other LPA receptors has been suggested. From studies on knockout mice and hereditary diseases of these LPA receptors, it is now clear that LPA is involved in various biological processes including brain development and embryo implantation, as well as patho-physiological conditions including neuropathic pain and pulmonary and renal fibrosis. Unlike sphingosine 1-phosphate, a structurally similar bio-active lysophospholipid to LPA and produced intracellularly, LPA is produced by multiple extracellular degradative routes. A plasma enzyme called autotaxin (ATX) is responsible for the most of LPA production in our bodies. ATX converts lysophospholipids such as lysophosphatidylcholine to LPA by its lysophospholipase D activity. Recent studies on ATX have revealed new aspects of LPA. In this review, we highlight recent advances in our understanding of LPA functions and several aspects of ATX, including its activity, expression, structure, biochemical properties, the mechanism by which it stimulates cell motility and its pahto-physiological function through LPA production.
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Wu JM, Xu Y, Skill NJ, Sheng H, Zhao Z, Yu M, Saxena R, Maluccio MA. Autotaxin expression and its connection with the TNF-alpha-NF-kappaB axis in human hepatocellular carcinoma. Mol Cancer 2010; 9:71. [PMID: 20356387 PMCID: PMC2867819 DOI: 10.1186/1476-4598-9-71] [Citation(s) in RCA: 109] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2009] [Accepted: 03/31/2010] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Autotaxin (ATX) is an extracellular lysophospholipase D that generates lysophosphatidic acid (LPA) from lysophosphatidylcholine (LPC). Both ATX and LPA have been shown to be involved in many cancers. However, the functional role of ATX and the regulation of ATX expression in human hepatocellular carcinoma (HCC) remain elusive. RESULTS In this study, ATX expression was evaluated in tissues from 38 human HCC and 10 normal control subjects. ATX was detected mainly in tumor cells within tissue sections and its over-expression in HCC was specifically correlated with inflammation and liver cirrhosis. In addition, ATX expression was examined in normal human hepatocytes and liver cancer cell lines. Hepatoma Hep3B and Huh7 cells displayed stronger ATX expression than hepatoblastoma HepG2 cells and normal hepatocytes did. Proinflammtory cytokine tumor necrosis factor alpha (TNF-alpha) promoted ATX expression and secretion selectively in Hep3B and Huh7 cells, which led to a corresponding increase in lysophospholipase-D activity. Moreover, we explored the mechanism governing the expression of ATX in hepatoma cells and established a critical role of nuclear factor-kappa B (NF-kappaB) in basal and TNF-alpha induced ATX expression. Further study showed that secreted enzymatically active ATX stimulated Hep3B cell invasion. CONCLUSIONS This report highlights for the first time the clinical and biological evidence for the involvement of ATX in human HCC. Our observation that links the TNF-alpha/NF-kappaB axis and the ATX-LPA signaling pathway suggests that ATX is likely playing an important role in inflammation related liver tumorigenesis.
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Affiliation(s)
- Jian-Min Wu
- Department of Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
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18
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Abstract
Autotaxin is a protein of approximately 900 amino acids discovered in the early 1990s. Over the past 15 years, a strong association between cancer cells and autotaxin production has been observed. Recent publications indicate that autotaxin and the capacity of cancer to metastasise are intimately linked. The discovery of new molecular targets in pharmacology is a mixture of pure luck, hard work and industrial strategy. Despite a crucial and desperate need for new therapeutic tools, many targets are approached in oncology, but only a few are validated and end up at the patient bed. Outside the busy domain of kinases, few targets have been discovered that can be useful in treating cancer, particularly metastatic processes. The fortuitous relationship between autotaxin and lysophosphatidic acid renders the results of observations made in the diabetes/obesity context considerably important. The literature provides observations that may aid in redesigning experiments to validate autotaxin as a potential oncology target.
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Affiliation(s)
- Jean A Boutin
- Pharmacologie Moléculaire et Cellulaire, Institut de Recherches SERVIER, Croissy-sur-Seine, France.
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19
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Federico L, Pamuklar Z, Smyth SS, Morris AJ. Therapeutic potential of autotaxin/lysophospholipase d inhibitors. Curr Drug Targets 2008; 9:698-708. [PMID: 18691016 DOI: 10.2174/138945008785132439] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Lysophosphatidic acids (LPAs) are structurally simple lipid phosphate esters with a widely appreciated role as extracellular signaling molecules. LPA binds to selective cell surface receptors to promote cell growth, survival, motility and differentiation. Studies using LPA receptor knockout mice and experimental therapeutics targeting these receptors identify roles for LPA signaling in processes that include cardiovascular disease and function, angiogenesis, reproduction, cancer progression and neuropathic pain. These studies identify considerable functional redundancy between these receptors and raise the possibility that additional lysophosphatidic acid receptors remain to be identified. LPA is present in the blood and other biological fluids at physiologically relevant concentrations and can likely be rapidly generated and degraded in different locations, for example at sites of inflammation, vascular injury and thrombosis or in the tumor micro environment. Recent work identifies a secreted enzyme, autotaxin (ATX), as the key component of an extracellular pathway for generation of lysophosphatidic acid by lysophospholipase D catalyzed hydrolysis of lysophospholipid substrates. In contrast to the apparently redundant functions of LPA receptors, studies using ATX knock out and transgenic mice indicate that this enzyme is uniquely required for LPA signaling during early development and serves as the primary determinant of circulating LPA levels in adult animals. Accordingly, pharmacological inhibition of ATX may be a viable and potentially effective way to interfere with LPA signaling in the cardiovascular system and possibly other settings such as tumor metastasis for therapeutic benefit. In this review we provide an update on recent advances in defining roles for LPA signaling in major disease processes and discuss recent progress in understanding the regulation and function of autotaxin focusing on strategies for the identification and initial evaluation of small molecule autotaxin inhibitors.
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Affiliation(s)
- Lorenzo Federico
- Division of Cardiovascular Medicine, The Gill Heart Institute, 900 S. Limestone Street, 326 CTW Building, Lexington, KY 40536-0200, USA
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Yuelling LM, Fuss B. Autotaxin (ATX): a multi-functional and multi-modular protein possessing enzymatic lysoPLD activity and matricellular properties. BIOCHIMICA ET BIOPHYSICA ACTA 2008; 1781:525-30. [PMID: 18485925 PMCID: PMC2564869 DOI: 10.1016/j.bbalip.2008.04.009] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2008] [Revised: 04/15/2008] [Accepted: 04/19/2008] [Indexed: 01/02/2023]
Abstract
Recent studies have established that autotaxin (ATX), also known as phosphodiesterase Ialpha/autotaxin (PD-Ialpha/ATX) or (ecto)nucleotide pyrophosphatase/phosphodiesterase 2 [(E)NPP2], represents a multi-functional and multi-modular protein. ATX was initially thought to function exclusively as a phosphodiesterase/pyrophosphatase. However, it has become apparent that this enzymatically active site, which is ultimately responsible for ATX's originally discovered property of tumor cell motility stimulation, mediates the conversion of lysophosphatidylcholine (LPC) to lysophosphatidic acid (LPA). In addition, a separate functionally active domain, here referred to as the Modulator of Oligodendrocyte Remodeling and Focal adhesion Organization (MORFO) domain, was discovered in studies analyzing the role of ATX during the differentiation of myelinating cells of the central nervous system (CNS), namely oligodendrocytes. This novel domain was found to mediate anti-adhesive, i.e. matricellular, properties and to promote morphological maturation of oligodendrocytes. In this review, we summarize our current understanding of ATX's structure-function domains and discuss their contribution to the presently known main functional roles of ATX.
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Affiliation(s)
- Larra M Yuelling
- Department of Anatomy and Neurobiology, Virginia Commonwealth University School of Medicine, PO Box 980709, Richmond, VA 23298, USA
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21
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Kanda H, Newton R, Klein R, Morita Y, Gunn MD, Rosen SD. Autotaxin, an ectoenzyme that produces lysophosphatidic acid, promotes the entry of lymphocytes into secondary lymphoid organs. Nat Immunol 2008; 9:415-23. [PMID: 18327261 DOI: 10.1038/ni1573] [Citation(s) in RCA: 211] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2007] [Accepted: 02/08/2008] [Indexed: 12/23/2022]
Abstract
The extracellular lysophospholipase D autotaxin (ATX) and its product, lysophosphatidic acid, have diverse functions in development and cancer, but little is known about their functions in the immune system. Here we found that ATX had high expression in the high endothelial venules of lymphoid organs and was secreted. Chemokine-activated lymphocytes expressed receptors with enhanced affinity for ATX, which provides a mechanism for targeting the secreted ATX to lymphocytes undergoing recruitment. Lysophosphatidic acid induced chemokinesis in T cells. Intravenous injection of enzymatically inactive ATX attenuated the homing of T cells to lymphoid tissues, probably through competition with endogenous ATX and exertion of a dominant negative effect. Our results support the idea of a new and general step in the homing cascade in which the ectoenzyme ATX facilitates the entry of lymphocytes into lymphoid organs.
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Affiliation(s)
- Hidenobu Kanda
- Department of Anatomy, Program in Immunology, Cardiovascular Research Institute, University of California San Francisco, San Francisco, California 94143, USA
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22
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Actin cytoskeletal mediators of motility and invasion amplified and overexpressed in head and neck cancer. Clin Exp Metastasis 2008; 25:289-304. [DOI: 10.1007/s10585-008-9154-6] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2008] [Accepted: 02/19/2008] [Indexed: 01/10/2023]
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23
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Haga A, Hashimoto K, Tanaka N, Nakamura KT, Deyashiki Y. Scalable purification and characterization of the extracellular domain of human autotaxin from prokaryotic cells. Protein Expr Purif 2008; 59:9-17. [PMID: 18249559 DOI: 10.1016/j.pep.2007.12.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2007] [Revised: 12/04/2007] [Accepted: 12/07/2007] [Indexed: 10/22/2022]
Abstract
Autotaxin (ATX) is an approximately 125kDa transmembrane protein known as a tumor progression factor based on its lysophospholipase D (lysoPLD) activity. There are many reports of the biological and biochemical properties of ATX, but crystallographic or structural studies have not been reported because a large-scale production process using prokaryotic cells has not been established. Here we report a bulk purification process and soluble expression of the recombinant human ATX (rhATX S48) from prokaryotic cells. The extracellular domain of human ATX cDNA was cloned into a pET101/D-TOPO vector and transformed to an Escherichia coliBL21 strain which was co-transformed with a pTF16 chaperone plasmid. The rhATX S48 was purified with chaperone and it was removed by Mg(2+)-ATP treatment. The final yield of purified rhATX S48 was approximately 3.5mg/l culture of recombinant strain. The rhATX S48 shows lysoPLD enzymatic activity and effectively stimulates the growth and motile activity of the human tumor cells as well as native ATX. This is a first report for scalable purification of the ATX molecule and the rhATX S48 should be a good tool for immunization of anti-ATX or crystallographic analysis of ATX.
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Affiliation(s)
- Arayo Haga
- Research Institute for Health and Environmental Science, Gifu Prefectural Government, 1-1, Naka-Fudougaoka, Kakamigahara 504-0838, Japan.
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24
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Dennis J, White MA, Forrest AD, Yuelling LM, Nogaroli L, Afshari FS, Fox MA, Fuss B. Phosphodiesterase-Ialpha/autotaxin's MORFO domain regulates oligodendroglial process network formation and focal adhesion organization. Mol Cell Neurosci 2007; 37:412-24. [PMID: 18164210 DOI: 10.1016/j.mcn.2007.10.018] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2007] [Revised: 10/23/2007] [Accepted: 10/30/2007] [Indexed: 10/22/2022] Open
Abstract
Development of a complex process network by maturing oligodendrocytes is a critical but currently poorly characterized step toward myelination. Here, we demonstrate that the matricellular oligodendrocyte-derived protein phosphodiesterase-Ialpha/autotaxin (PD-Ialpha/ATX) and especially its MORFO domain are able to promote this developmental step. In particular, the single EF hand-like motif located within PD-Ialpha/ATX's MORFO domain was found to stimulate the outgrowth of higher order branches but not process elongation. This motif was also observed to be critical for the stimulatory effect of PD-Ialpha/ATX's MORFO domain on the reorganization of focal adhesions located at the leading edge of oligodendroglial protrusions. Collectively, our data suggest that PD-Ialpha/ATX promotes oligodendroglial process network formation and expansion via the cooperative action of multiple functional sites located within the MORFO domain and more specifically, a novel signaling pathway mediated by the single EF hand-like motif and regulating the correlated events of process outgrowth and focal adhesion organization.
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Affiliation(s)
- Jameel Dennis
- Department of Anatomy and Neurobiology, Virginia Commonwealth University School of Medicine, Richmond, VA 23298, USA
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25
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Ferry G, Giganti A, Cogé F, Bertaux F, Thiam K, Boutin JA. Functional invalidation of the autotaxin gene by a single amino acid mutation in mouse is lethal. FEBS Lett 2007; 581:3572-8. [PMID: 17628547 DOI: 10.1016/j.febslet.2007.06.064] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2007] [Accepted: 06/26/2007] [Indexed: 11/25/2022]
Abstract
Autotaxin is a member of the phosphodiesterase family of enzymes, (NPP2). It is an important secreted protein found in conditioned medium from adipocytes. It also has a putative role in the metastatic process. Based on these observation, further validation of this potential target was necessary, apart from the classical biochemical ones. The construction of a knock out mouse strain for ATX was started. In this paper, we report the generation of a mouse line displaying an inactivated ATX gene product. The KO line was designed in order to generate a functional inactivation of the protein. In this respect, the threonine residue T210 was replaced by an alanine (T210A) leading to a catalytically inactive enzyme. If the experimental work was straight forward, we disappointedly discovered at the final stage that the breeding of heterozygous animals, ATX -/+, led to the generation of a Mendelian repartition of wild-type and heterozygous, but no homozygous were found, strongly suggesting that the ATX deletion is lethal at an early stage of the development. This was confirmed by statistical analysis. Although other reported the same lethality for attempted ATX-/- mice generation [van Meeteren, L.A., Ruurs, P., Stortelers, C., Bouwman, P., van Rooijen, M.A., Pradère, J.P., Pettit, T.R., Wakelam, M.J.O., Saulnier-Blache, J.S., Mummery, C.L., Moolenar, W.H. and Jonkers, J. (2006) Autotaxin, a secreted lysophospholipase D, is essential for blood vessel formation during development, Mol. Cell. Biol. 26, 5015-5022; Tanaka, M., Okudaira, S., Kishi, Y., Ohkawa, R., Isei, S., Ota, M., Noji, S., Yatomi, Y., Aoki, J., and Arai, H. (2006) Autotaxin stabilizes blood vessels and is required for embryonic vasculature by producing lysophosphatidic acid, J. Biol. Chem. 281, 25822-25830], they used more drastic multiple exon deletions in the ATX gene, while we chose a single point mutation. To our knowledge, the present work is the first showing such a lethality in any gene after a point mutation in an enzyme catalytic site.
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Affiliation(s)
- Gilles Ferry
- Pharmacologie Moléculaire et Cellulaire, Institut de Recherches Servier, 125 Chemin de Ronde, 78290 Croissy-sur-Seine, France
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26
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Koike S, Keino-Masu K, Ohto T, Masu M. The N-terminal hydrophobic sequence of autotaxin (ENPP2) functions as a signal peptide. Genes Cells 2007; 11:133-42. [PMID: 16436050 DOI: 10.1111/j.1365-2443.2006.00924.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Autotaxin, also known as ENPP2, was originally isolated from the culture medium of melanoma cells as a cell-motility promoting protein. It regulates cell growth, motility, and angiogenesis through the production of lysophosphatidic acid and sphingosine 1-phosphate. Because autotaxin shows overall structural similarity to the well-characterized PC-1, it has been assumed to be a type II transmembrane protein that is expressed on the cell surface and is released into the extracellular space after proteolytic cleavage. We found, however, that while autotaxin was efficiently secreted into the extracellular space both in vitro and in vivo, it was expressed neither on the surfaces of autotaxin-transfected cells nor on those of the autotaxin-expressing choroid plexus epithelium cells. N-terminal sequencing of the secreted autotaxin revealed that it was cleaved at two N-terminal sites that match the consensus sequences for cleavage by a signal peptidase and furin. In addition, when translated in vitro, autotaxin was co-translationally translocated into microsome membranes, and its N-terminal 3-kDa fragment corresponding to a signal sequence was cleaved. These data demonstrate that the N-terminal hydrophobic sequence of autotaxin functions as a signal peptide, not as a transmembrane segment, and thus autotaxin is synthesized as a secreted protein.
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Affiliation(s)
- Seiichi Koike
- Department of Molecular Neurobiology, Institute of Basic Medical Sciences, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan
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27
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Kishi Y, Okudaira S, Tanaka M, Hama K, Shida D, Kitayama J, Yamori T, Aoki J, Fujimaki T, Arai H. Autotaxin is overexpressed in glioblastoma multiforme and contributes to cell motility of glioblastoma by converting lysophosphatidylcholine to lysophosphatidic acid. J Biol Chem 2006; 281:17492-17500. [PMID: 16627485 DOI: 10.1074/jbc.m601803200] [Citation(s) in RCA: 173] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Autotaxin (ATX) is a multifunctional phosphodiesterase originally isolated from melanoma cells as a potent cell motility-stimulating factor. ATX is identical to lysophospholipase D, which produces a bioactive phospholipid, lysophosphatidic acid (LPA), from lysophosphatidylcholine (LPC). Although enhanced expression of ATX in various tumor tissues has been repeatedly demonstrated, and thus, ATX is implicated in progression of tumor, the precise role of ATX expressed by tumor cells was unclear. In this study, we found that ATX is highly expressed in glioblastoma multiforme (GBM), the most malignant glioma due to its high infiltration into the normal brain parenchyma, but not in tissues from other brain tumors. In addition, LPA1, an LPA receptor responsible for LPA-driven cell motility, is predominantly expressed in GBM. One of the glioblastomas that showed the highest ATX expression (SNB-78), as well as ATX-stable transfectants, showed LPA1-dependent cell migration in response to LPA in both Boyden chamber and wound healing assays. Interestingly these ATX-expressing cells also showed chemotactic response to LPC. In addition, knockdown of the ATX level using small interfering RNA technique in SNB-78 cells suppressed their migratory response to LPC. These results suggest that the autocrine production of LPA by cancer cell-derived ATX and exogenously supplied LPC contribute to the invasiveness of cancer cells and that LPA1, ATX, and LPC-producing enzymes are potential targets for cancer therapy, including GBM.
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Affiliation(s)
- Yasuhiro Kishi
- Graduate School of Pharmaceutical Sciences, the University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033
| | - Shinichi Okudaira
- Graduate School of Pharmaceutical Sciences, the University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033
| | - Masayuki Tanaka
- Graduate School of Pharmaceutical Sciences, the University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033
| | - Kotaro Hama
- Graduate School of Pharmaceutical Sciences, the University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033
| | - Dai Shida
- Graduate School of Medicine, the University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033
| | - Joji Kitayama
- Graduate School of Medicine, the University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033
| | - Takao Yamori
- Division of Molecular Pharmacology, Cancer Chemotherapy Center, Japanese Foundation for Cancer Research, Toshima-ku, Tokyo 170-8455
| | - Junken Aoki
- Graduate School of Pharmaceutical Sciences, the University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033.
| | - Takamitsu Fujimaki
- Department of Neurosurgery, Teikyo University School of Medicine, 2-11-1, Kaga, Itabashi-ku, Tokyo 173-8605, Japan
| | - Hiroyuki Arai
- Graduate School of Pharmaceutical Sciences, the University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033
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Noh JH, Ryu SY, Eun JW, Song J, Ahn YM, Kim SY, Lee SH, Park WS, Yoo NJ, Lee JY, Lee SN, Nam SW. Identification of large-scale molecular changes of Autotaxin(ENPP2) knock-down by small interfering RNA in breast cancer cells. Mol Cell Biochem 2006; 288:91-106. [PMID: 16601922 DOI: 10.1007/s11010-006-9124-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2005] [Accepted: 01/09/2006] [Indexed: 10/24/2022]
Abstract
To understand comprehensive molecular mechanisms by which Autotaxin (ENPP2) mediates, we identified large-scale molecular changes responsible for aberrant expression of Autotaxin (ATX) on breast cancer cells by using DNA microarrays. Transcriptional over-expression of ENPP2 gene was endogenously silenced by using RNA interference technique, and then recapitulated corresponding molecular changes in MDA435 breast cancer cells. Application of nonparametric Wilcoxon statistical analyses (P<0.05) and the selection criteria of 2-fold differential gene expression change resulted in the identification of 368 genes including 133 up-regulated and 235 genes under-expressed in ENPP2-silencing MDA435 cells. Most of the functional categories of identified genes are associated with cellular metabolism, cytoskeleton organization, transcription regulation, signal transduction as well as cellular organization and biogenesis. Our data suggest that the molecular signature identified by the ENPP2-silencing methods may represent potential candidates that can explain the complicated characteristics of ATX and may serve as biomarkers, for the development of molecular-targeting therapy, in human breast cancer.
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Affiliation(s)
- Ji Heon Noh
- Department of Pathology, College of Medicine and Microdissection Genomics Research Center, The Catholic University of Korea, Banpo-dong #505, Seocho-gu, Seoul, 137-701, Korea
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Kohn EC, Travers LA, Kassis J, Broome U, Klominek J. Malignant effusions are sources of fibronectin and other promigratory and proinvasive components. Diagn Cytopathol 2006; 33:300-8. [PMID: 16240400 DOI: 10.1002/dc.20279] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Metastatic dissemination is the primary cause of death in ovarian cancer (OvCa) patients, and dissemination to pleural and peritoneal effusions is a common clinical event. Effusion samples were collected from 15 OvCa patients. Twenty-six samples were collected prospectively, two were archival, and eight were taken from patients with other malignancies. Twenty-nine samples were from malignant ascites, and seven specimens were pleural fluids. In addition, six ascites and two pleural fluids from noncancer patients were studied as effusion controls. Effusion supernatants were tested for migration-stimulation activity, using A2058 human melanoma cells as the index responder cell. Malignant samples induced a 400-1200% increase in migration. Sixty percent of the migration was inhibited by incubation of the malignant fluid with antifibronectin (FN) antibody, in contrast to 75% inhibition of control fluid-stimulated migration (P = 0.017). Gelatin zymography and Western blot analyses showed that latent and activated MMP-2 and MMP-9 collagenases, and tissue inhibitor of metalloproteinase-2 (TIMP-2) were present in all malignant fluids. Serial samples were taken from several patients, and a trend for correlation between MMPs and clinical behavior of the tumors was shown. Free TIMP-2 correlated with CA-125 levels in two patients for whom serial samples were available. The demonstration of promigratory and proinvasive activity in malignant effusions is consistent with their association with other metastatic disease in OvCa patients and their function as a haven for metastatic cells.
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Affiliation(s)
- E C Kohn
- Molecular Signaling Section, Laboratory of Pathology, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland 20892, USA.
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Song J, Jie C, Polk P, Shridhar R, Clair T, Zhang J, Yin L, Keppler D. The candidate tumor suppressor CST6 alters the gene expression profile of human breast carcinoma cells: down-regulation of the potent mitogenic, motogenic, and angiogenic factor autotaxin. Biochem Biophys Res Commun 2005; 340:175-82. [PMID: 16356477 DOI: 10.1016/j.bbrc.2005.11.171] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2005] [Accepted: 11/23/2005] [Indexed: 02/06/2023]
Abstract
We recently coined CST6 as a novel candidate tumor suppressor gene for breast cancer. CST6 indeed is expressed in the normal human breast epithelium, but little or not at all in breast carcinomas and breast cancer cell lines. Moreover, ectopic expression of CST6 in human breast cancer cells suppressed cell proliferation, migration, invasion, and orthotopic tumor growth. To obtain insights into the molecular mechanism by which CST6 exhibits its pleiotropic effects on tumor cells, we compared global gene expression profiles in mock- and CST6-transfected human MDA-MB-435S cells. Out of 12,625 transcript species, 61 showed altered expression. These included genes for extracellular matrix components, cytokines, kinases, and phosphatases, as well as several key transcription factors. TaqMan PCR assays were used to confirm the microarray data for 7 out of 11 genes. One down-regulated gene product, secreted autotaxin/lyso-phospholipase D, was of particular interest because its down-regulation by CST6 could explain most of CST6's effect on the breast cancer cells. This study thus provides the first evidence that CST6 plays a role in the modulation of genes, particularly, genes that are highly relevant to breast cancer progression.
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Affiliation(s)
- Jin Song
- Department of Cellular Biology and Anatomy, Louisiana State University Health Sciences Center, Shreveport, USA
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31
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Abstract
Lysophosphatidic acid (LPA; 1-acyl-3-phosphoglycerol) exerts its biological activity through both extracellular and intracellular targets. Receptor targets include the cell-surface G-protein-coupled receptors LPA(1-4) and the nuclear PPAR-gamma (peroxisome-proliferator-activated receptor gamma). Enzyme targets include the secreted cancer cell motility factor, autotaxin, and the transmembrane phosphatases, LPP1-3 (where LPP stands for lipid phosphate phosphatase). Ion channel targets include the two pore domain ion channels in the TREK family, TREK-1, TREK-2 and TRAAK. Structural features of these targets and their interactions with LPA are reviewed.
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32
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Song J, Clair T, Noh JH, Eun JW, Ryu SY, Lee SN, Ahn YM, Kim SY, Lee SH, Park WS, Yoo NJ, Lee JY, Nam SW. Autotaxin (lysoPLD/NPP2) protects fibroblasts from apoptosis through its enzymatic product, lysophosphatidic acid, utilizing albumin-bound substrate. Biochem Biophys Res Commun 2005; 337:967-75. [PMID: 16219296 DOI: 10.1016/j.bbrc.2005.09.140] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2005] [Accepted: 09/21/2005] [Indexed: 01/02/2023]
Abstract
Autotaxin (ATX) was originally identified as a potent tumor cell motility-stimulating factor that displays multiple enzymatic activities including ATPase, Type I nucleotide pyrophosphatase/phosphodiesterase, and lysophospholipase D, depending on its substrates. We demonstrate herein that ATX is a key regulator of extracellular lysophosphatidic acid (LPA) that can act as survival factor, in addition to its mitogenic activity in mouse fibroblasts. Introduction of atx gene into NIH3T3 cells resulted in resistance to conditional apoptosis induced by serum-deprivation, and exogenous ATX protein prevented cells from death by starvation. Flow cytometric analysis showed that co-treatment of ATX with lysophosphatidylcholine as substrate rescued NIH3T3 cells from cellular apoptosis, and this survival activity of ATX was also demonstrated by caspase-3 degradation and PARP cleavage resulting from the enzymatic activity of extracellular ATX. Furthermore, the effect of ATX in preventing apoptosis appears to be mediated through the G-protein-coupled receptor pathway followed by the activation of phosphoinositide 3-kinase and Akt pathway leading to enhanced cell survival. These findings provide novel insights into understanding the functions of ATX as a key regulator of bioactive phospholipids and suggest interventions to correct dysfunction in conditions of tumor cell growth and metastasis.
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Affiliation(s)
- Jaehwi Song
- Department of Pathology, College of Medicine and Microdissection Genomics Research Center, The Catholic University of Korea, Banpo-dong number 505, Seocho-gu, Seoul 137-701, Republic of Korea
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Geho DH, Bandle RW, Clair T, Liotta LA. Physiological mechanisms of tumor-cell invasion and migration. Physiology (Bethesda) 2005; 20:194-200. [PMID: 15888576 DOI: 10.1152/physiol.00009.2005] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Recent advances in understanding the complex biology of the microenvironment that underlies tumor invasion and migration have revealed novel and promising therapeutic targets. Pharmacological blockade of intra- and extracellular signaling events that regulate migration and survival of multiple cell types may disrupt the host-tumor conspiracy that allows escape from normal developmental regulation.
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Affiliation(s)
- David H Geho
- Laboratory of Pathology, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA.
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34
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Sakagami H, Aoki J, Natori Y, Nishikawa K, Kakehi Y, Natori Y, Arai H. Biochemical and molecular characterization of a novel choline-specific glycerophosphodiester phosphodiesterase belonging to the nucleotide pyrophosphatase/phosphodiesterase family. J Biol Chem 2005; 280:23084-93. [PMID: 15788404 DOI: 10.1074/jbc.m413438200] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Nucleotide pyrophosphatases/phosphodiesterases (NPPs) are ubiquitous membrane-associated or secreted ectoenzymes that release nucleoside 5'-monophosphate from a variety of nucleotides and nucleotide derivatives. The mammalian NPP family comprises seven members, but only three of these (NPP1-3) have been studied in some detail. Previously we showed that lysophospholipase D, which hydrolyzes lysophosphatidylcholine (LPC) to produce lysophosphatidic acid, is identical to NPP2. More recently an uncharacterized novel NPP member (NPP7) was shown to have alkaline sphingomyelinase activity. These findings raised the possibility that other members of the NPP family act on phospholipids. Here we show that the sixth member of the NPP family, NPP6, is a choline-specific glycerophosphodiester phosphodiesterase. The sequence of NPP6 encodes a transmembrane protein containing an NPP domain with significant homology to NPP4, NPP5, and NPP7/alkaline sphingomyelinase. When expressed in HeLa cells, NPP6 was detected in both the cells and the cell culture medium as judged by Western blotting and by enzymatic activity. Recombinant NPP6 efficiently hydrolyzed the classical substrate for phospholipase C, p-nitrophenyl phosphorylcholine, but not the classical nucleotide phosphodiesterase substrate, p-nitrophenyl thymidine 5'-monophosphate. In addition, NPP6 hydrolyzed LPC to form monoacylglycerol and phosphorylcholine but not lysophosphatidic acid, showing it has a lysophospholipase C activity. NPP6 showed a preference for LPC with short (12:0 and 14:0) or polyunsaturated (18:2 and 20:4) fatty acids. It also hydrolyzed glycerophosphorylcholine and sphingosylphosphorylcholine efficiently. In mice, NPP6 mRNA was predominantly detected in kidney with a lesser expression in brain and heart, and in human it was detected in kidney and brain. The present results suggest that NPP6 has a specific role through the hydrolysis of polyunsaturated LPC, glycerophosphorylcholine, or sphingosylphosphorylcholine in these organs.
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MESH Headings
- Amino Acid Sequence
- Animals
- Antibodies, Monoclonal/chemistry
- Base Sequence
- Blotting, Northern
- Blotting, Western
- Brain/enzymology
- Cations
- Cell Membrane/metabolism
- Cell Movement
- Fatty Acids/chemistry
- Glycerylphosphorylcholine/chemistry
- HeLa Cells
- Humans
- Hydrolysis
- Immunohistochemistry
- Kidney/enzymology
- Kinetics
- Lysophosphatidylcholines/chemistry
- Lysophosphatidylcholines/metabolism
- Mice
- Microscopy, Fluorescence
- Models, Biological
- Models, Chemical
- Molecular Sequence Data
- Myocardium/enzymology
- Nephrons/metabolism
- Phospholipids/metabolism
- Phosphoric Diester Hydrolases
- Phosphorylcholine/analogs & derivatives
- Phosphorylcholine/chemistry
- Phylogeny
- Protein Binding
- Protein Structure, Tertiary
- Pyrophosphatases/chemistry
- Pyrophosphatases/metabolism
- RNA, Messenger/metabolism
- Recombinant Proteins/chemistry
- Reverse Transcriptase Polymerase Chain Reaction
- Sequence Analysis, DNA
- Sequence Homology, Amino Acid
- Species Specificity
- Sphingomyelin Phosphodiesterase/chemistry
- Sphingomyelin Phosphodiesterase/metabolism
- Sphingomyelin Phosphodiesterase/physiology
- Sphingosine/analogs & derivatives
- Sphingosine/chemistry
- Swine
- Time Factors
- Tissue Distribution
- Transfection
- Type C Phospholipases/chemistry
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Affiliation(s)
- Hideki Sakagami
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Japan
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35
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van Meeteren LA, Ruurs P, Christodoulou E, Goding JW, Takakusa H, Kikuchi K, Perrakis A, Nagano T, Moolenaar WH. Inhibition of autotaxin by lysophosphatidic acid and sphingosine 1-phosphate. J Biol Chem 2005; 280:21155-61. [PMID: 15769751 DOI: 10.1074/jbc.m413183200] [Citation(s) in RCA: 166] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Autotaxin (ATX) or nucleotide pyrophosphatase/phosphodiesterase 2 (NPP2) is an NPP family member that promotes tumor cell motility, experimental metastasis, and angiogenesis. ATX primarily functions as a lysophospholipase D, generating the lipid mediator lysophosphatidic acid (LPA) from lysophosphatidylcholine. ATX uses a single catalytic site for the hydrolysis of both lipid and non-lipid phosphodiesters, but its regulation is not well understood. Using a new fluorescence resonance energy transfer-based phosphodiesterase sensor that reports ATX activity with high sensitivity, we show here that ATX is potently and specifically inhibited by LPA and sphingosine 1-phosphate (S1P) in a mixed-type manner (Ki approximately 10(-7) M). The homologous ecto-phosphodiesterase NPP1, which lacks lysophospholipase D activity, is insensitive to LPA and S1P. Our results suggest that, by repressing ATX activity, LPA can regulate its own biosynthesis in the extracellular environment, and they reveal a novel role for S1P as an inhibitor of ATX, in addition to its well established role as a receptor ligand.
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Affiliation(s)
- Laurens A van Meeteren
- Division of Cellular Biochemistry and Center for Biomedical Genetics, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
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36
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Clair T, Koh E, Ptaszynska M, Bandle RW, Liotta LA, Schiffmann E, Stracke ML. L-histidine inhibits production of lysophosphatidic acid by the tumor-associated cytokine, autotaxin. Lipids Health Dis 2005; 4:5. [PMID: 15737239 PMCID: PMC554093 DOI: 10.1186/1476-511x-4-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2005] [Accepted: 02/28/2005] [Indexed: 11/24/2022] Open
Abstract
Background Autotaxin (ATX, NPP-2), originally purified as a potent tumor cell motility factor, is now known to be the long-sought plasma lysophospholipase D (LPLD). The integrity of the enzymatic active site, including three crucial histidine moieties, is required for motility stimulation, as well as LPLD and 5'nucleotide phosphodiesterase (PDE) activities. Except for relatively non-specific chelation agents, there are no known inhibitors of the ATX LPLD activity. Results We show that millimolar concentrations of L-histidine inhibit ATX-stimulated but not LPA-stimulated motility in two tumor cell lines, as well as inhibiting enzymatic activities. Inhibition is reversed by 20-fold lower concentrations of zinc salt. L-histidine has no significant effect on the Km of LPLD, but reduces the Vmax by greater than 50%, acting as a non-competitive inhibitor. Several histidine analogs also inhibit the LPLD activity of ATX; however, none has greater potency than L-histidine and all decrease cell viability or adhesion. Conclusion L-histidine inhibition of LPLD is not a simple stoichiometric chelation of metal ions but is more likely a complex interaction with a variety of moieties, including the metal cation, at or near the active site. The inhibitory effect of L-histidine requires all three major functional groups of histidine: the alpha amino group, the alpha carboxyl group, and the metal-binding imidazole side chain. Because of LPA's involvement in pathological processes, regulation of its formation by ATX may give insight into possible novel therapeutic approaches.
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Affiliation(s)
- Timothy Clair
- Laboratory of Pathology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Eunjin Koh
- Laboratory of Pathology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Malgorzata Ptaszynska
- Laboratory of Pathology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Russell W Bandle
- Laboratory of Pathology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Lance A Liotta
- Laboratory of Pathology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Elliott Schiffmann
- Laboratory of Pathology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Mary L Stracke
- Laboratory of Pathology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA
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37
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Fox MA, Alexander JK, Afshari FS, Colello RJ, Fuss B. Phosphodiesterase-I alpha/autotaxin controls cytoskeletal organization and FAK phosphorylation during myelination. Mol Cell Neurosci 2005; 27:140-50. [PMID: 15485770 DOI: 10.1016/j.mcn.2004.06.002] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2004] [Revised: 05/12/2004] [Accepted: 06/08/2004] [Indexed: 11/26/2022] Open
Abstract
Myelination within the central nervous system (CNS) involves substantial morphogenesis of oligodendrocytes requiring plastic changes in oligodendrocyte-extracellular matrix (ECM) interactions, that is, adhesion. Our previous studies indicated that a regulator of such adhesive plasticity is oligodendrocyte-released phosphodiesterase-I alpha/autotaxin (PD-I alpha/ATX). We report here, that PD-I alpha/ATX's adhesion antagonism is mediated by a protein fragment different from the one that stimulates tumor cell motility. Furthermore, PD-I alpha/ATX's adhesion-antagonizing fragment causes a reorganized distribution of the focal adhesion components vinculin and paxillin and an integrin-dependent reduction in focal adhesion kinase (FAK) phosphorylation at tyrosine residue 925 (pFAK-925). In vivo, a similar reduction in pFAK-925 occurs at the onset of myelination when PD-I alpha/ATX expression is significantly upregulated. Most importantly, it can also be induced by the application of exogenous PD-I alpha/ATX. Our data, therefore, suggest that PD-I alpha/ATX participates in the regulation of myelination via a novel signaling pathway leading to changes in integrin-dependent focal adhesion assembly and consequently oligodendrocyte-ECM interactions.
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Affiliation(s)
- Michael A Fox
- Department of Anatomy and Neurobiology, Virginia Commonwealth University, Richmond, VA 23298, USA
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38
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Abstract
Lysophosphatidic acid is one of the most attractive phospholipid mediator with multiple biological functions and is implicated in various human diseases. In the past ten years much has been learned about the physiological roles of LPA through series of studies on LPA actions and its receptors. However, the molecular mechanisms of LPA have been poorly understood. LPA is produced in various conditions both in cells and in biological fluids, where multiple synthetic reactions occur. At least two pathways are postulated. In serum and plasma, LPA is mainly converted from lysophospholipids. By contrast, in platelets and some cancer cells, LPA is converted from phosphatidic acid. In each pathway, at least two phospholipase activities are required: phospholipase A1 (PLA1)/PLA2 plus lysophospholipase D (lysoPLD) activities are involved in the first pathway and phospholipase D (PLD) plus PLA1/PLA2 activities are involved in the second pathway. Now multiple phospholipases are identified that account for PLA1, PLA2, PLD, and lysoPLD activities. In the absence of specific inhibitors and genetically modified animals and individuals, the contribution of each phospholipase to LPA production can not be easily determined. However, apparently certain extracellular phospholipases such as secretory PLA2 (sPLA2-IIA), membrane-associated PA-selective PLA1 (mPA-PLA1), lecithin-cholesterol acyltransferase (LCAT), and lysoPLD are involved in LPA production.
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Affiliation(s)
- Junken Aoki
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
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39
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Le Stunff H, Milstien S, Spiegel S. Generation and metabolism of bioactive sphingosine-1-phosphate. J Cell Biochem 2004; 92:882-99. [PMID: 15258913 DOI: 10.1002/jcb.20097] [Citation(s) in RCA: 159] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Sphingosine-1-phosphate (S1P) is a bioactive lysosphingophospholipid that has been implicated in the regulation of vital biological processes. Abundant evidence indicates that S1P acts as both an intracellular messenger and an extracellular ligand for a family of five specific G protein-coupled S1P receptors (S1PRs). Cellular levels of S1P are tightly regulated in a spatio-temporal manner through its synthesis catalyzed by sphingosine kinases (SphKs) and degradation by S1P lyase (SPL) and specific S1P phosphohydrolases. Over the past decade, the identification and cloning of genes encoding S1P metabolizing enzymes has increased rapidly. Overexpression and deletion of these enzymes has provided important insights into the intracellular and the "inside-out" functions of S1P. The purpose of this review is to summarize the current knowledge of S1P metabolizing enzymes, their enzymatic properties, and their roles in the control of cellular functions by S1P.
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Affiliation(s)
- Hervé Le Stunff
- Laboratoire d'Activation Cellulaire et Transduction des Signaux, Institut de Biochimie et de Biophysique Moléculaire et Cellulaire, UMR CNRS 8619, Université Paris-Sud, 91405 Orsay, France
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40
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Quiñones LG, Garcia-Castro I. CHARACTERIZATION OF HUMAN MELANOMA CELL LINES ACCORDING TO THEIR MIGRATORY PROPERTIES IN VITRO. ACTA ACUST UNITED AC 2004; 40:35-42. [PMID: 14692828 DOI: 10.1290/1543-706x(2004)40<35:cohmcl>2.0.co;2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The migratory responses of four human melanoma cell lines (A-2058, DEMEL, HTB-63, and HTB-72), using chemotaxis (CTX) and haptotaxis (HPTX) assays, were studied. The attractants were three extracellular matrix components (EMCs), fibronectin, laminin, and collagen type IV. The conditioned media (CM) of each cell line were used to study autocrine and paracrine responses. A screening and sensitive CTX assay was performed, using pertussis toxin (PTX)- treated A-2058 as responder cells; the other melanoma cells and normal cells were used as secretory cells. Autotaxin (ATX), a purified autocrine motility factor, was also used as a chemoattractant. Reverse transcriptase-polymerase chain reaction was used to detect the expression of ATX by all cell lines. The secretion of ATX was determined by Western blot. The invasive capacity of the cell lines was evaluated using Matrigel and ATX as attractant. Chemotaxis responses to EMCs varied. Except for the A-2058 cells, HPTX migration was low. Autocrine and paracrine responses also varied. The migration of PTX-treated A-2058 cells to ATX and to their own CM was abolished. All the melanoma cells expressed ATX, and except for the HTB-72 and normal cells, all secreted ATX. Matrigel was invaded by all the melanoma cell lines except the HTB-72 and normal cells. The migratory properties of human melanoma cells in vitro suggest that they could correlate to their metastatic potential in vivo.
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Affiliation(s)
- Luis G Quiñones
- Biology Department, University of Puerto Rico, Río Piedras Campus, P.O. Box 22283, San Juan, PR 00931-2283
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41
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Fox MA, Colello RJ, Macklin WB, Fuss B. Phosphodiesterase-Ialpha/autotaxin: a counteradhesive protein expressed by oligodendrocytes during onset of myelination. Mol Cell Neurosci 2003; 23:507-19. [PMID: 12837632 DOI: 10.1016/s1044-7431(03)00073-3] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
The initial stages of central nervous system (CNS) myelination require complex interactions of oligodendrocytes with their surrounding extracellular environment. In the present study, we demonstrate that commencing with active myelination oligodendrocytes express phosphodiesterase-Ialpha/autotaxin [PD-Ialpha/ATX (NPP-2)] as a non-membrane-associated extracellular factor. As such a component of the extracellular environment, PD-Ialpha/ATX has the ability to antagonize the adhesive interactions between oligodendroglial cells and known extracellular matrix (ECM) molecules present in the developing CNS. This counteradhesion requires intracellular signaling through heterotrimeric G proteins on fibronectin substrates and thus represents an active cellular response. Similar counteradhesive effects in other systems have been attributed to the activity of matricellular proteins, which support intermediate stages of cell adhesion thought to facilitate cellular locomotion and remodeling. Thus, the release of PD-Ialpha/ATX may be critically involved in the regulation of the initial stages of myelination, i.e., oligodendrocyte remodeling, via modulation of oligodendrocyte-ECM interactions in a matricellular fashion.
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Affiliation(s)
- Michael A Fox
- Department of Anatomy and Neurobiology, Virginia Commonwealth University, Richmond, VA 23298, USA
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42
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Goding JW, Grobben B, Slegers H. Physiological and pathophysiological functions of the ecto-nucleotide pyrophosphatase/phosphodiesterase family. BIOCHIMICA ET BIOPHYSICA ACTA 2003; 1638:1-19. [PMID: 12757929 DOI: 10.1016/s0925-4439(03)00058-9] [Citation(s) in RCA: 271] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The ecto-nucleotide pyrophosphatase/phosphodiesterase (E-NPP) multigene family contains five members. NPP1-3 are type II transmembrane metalloenzymes characterized by a similar modular structure composed of a short intracellular domain, a single transmembrane domain and an extracellular domain containing a conserved catalytic site. The short intracellular domain of NPP1 has a basolateral membrane-targeting signal while NPP3 is targeted to the apical surface of polarized cells. NPP4-5 detected by database searches have a predicted type I membrane orientation but have not yet been functionally characterized. E-NPPs have been detected in almost all tissues often confined to specific substructures or cell types. In some cell types, NPP1 expression is constitutive or can be induced by TGF-beta and glucocorticoids, but the signal transduction pathways that control expression are poorly documented. NPP1-3 have a broad substrate specificity which may reflect their role in a host of physiological and biochemical processes including bone mineralization, calcification of ligaments and joint capsules, modulation of purinergic receptor signalling, nucleotide recycling, and cell motility. Abnormal NPP expression is involved in pathological mineralization, crystal depositions in joints, invasion and metastasis of cancer cells, and type 2 diabetes. In this review we summarize the present knowledge on the structure and the physiological and biochemical functions of E-NPP and their contribution to the pathogenesis of diseases.
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Affiliation(s)
- James W Goding
- Department of Pathology and Immunology, Monash Medical School, Monash University, 3181, Victoria, Prahran, Australia
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43
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Ferry G, Tellier E, Try A, Grés S, Naime I, Simon MF, Rodriguez M, Boucher J, Tack I, Gesta S, Chomarat P, Dieu M, Raes M, Galizzi JP, Valet P, Boutin JA, Saulnier-Blache JS. Autotaxin is released from adipocytes, catalyzes lysophosphatidic acid synthesis, and activates preadipocyte proliferation. Up-regulated expression with adipocyte differentiation and obesity. J Biol Chem 2003; 278:18162-9. [PMID: 12642576 PMCID: PMC1885458 DOI: 10.1074/jbc.m301158200] [Citation(s) in RCA: 190] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Our group has recently demonstrated (Gesta, S., Simon, M., Rey, A., Sibrac, D., Girard, A., Lafontan, M., Valet, P., and Saulnier-Blache, J. S. (2002) J. Lipid Res. 43, 904-910) the presence, in adipocyte conditioned-medium, of a soluble lysophospholipase d-activity (LPLDact) involved in synthesis of the bioactive phospholipid lysophosphatidic acid (LPA). In the present report, LPLDact was purified from 3T3F442A adipocyte-conditioned medium and identified as the type II ecto-nucleotide pyrophosphatase phosphodiesterase, autotaxin (ATX). A unique ATX cDNA was cloned from 3T3F442A adipocytes, and its recombinant expression in COS-7 cells led to extracellular release of LPLDact. ATX mRNA expression was highly up-regulated during adipocyte differentiation of 3T3F442A-preadipocytes. This up-regulation was paralleled by the ability of newly differentiated adipocytes to release LPLDact and LPA. Differentiation-dependent up-regulation of ATX expression was also observed in a primary culture of mouse preadipocytes. Treatment of 3T3F442A-preadipocytes with concentrated conditioned medium from ATX-expressing COS-7 cells led to an increase in cell number as compared with concentrated conditioned medium from ATX non-expressing COS-7 cells. The specific effect of ATX on preadipocyte proliferation was completely suppressed by co-treatment with a LPA-hydrolyzing phospholipase, phospholipase B. Finally, ATX expression was found in mature adipocytes isolated from mouse adipose tissue and was substantially increased in genetically obese-diabetic db/db mice when compared with their lean siblings. In conclusion, the present work shows that ATX is responsible for the LPLDact released by adipocytes and exerts a paracrine control on preadipocyte growth via an LPA-dependent mechanism. Up-regulations of ATX expression with adipocyte differentiation and genetic obesity suggest a possible involvement of this released protein in the development of adipose tissue and obesity-associated pathologies.
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Affiliation(s)
- Gilles Ferry
- Centre de Recherche de Croissy
Institut de Recherche Servier78290 Croissy-sur-Seine,FR
| | - Edwige Tellier
- Unité de recherche sur les obésités
INSERM : U586 IFR31Université Paul Sabatier - Toulouse IIIInstitut Louis Bugnard
1, Avenue Jean Poulhes
31432 TOULOUSE CEDEX 4,FR
| | - Anne Try
- Centre de Recherche de Croissy
Institut de Recherche Servier78290 Croissy-sur-Seine,FR
| | - Sandra Grés
- Unité de recherche sur les obésités
INSERM : U586 IFR31Université Paul Sabatier - Toulouse IIIInstitut Louis Bugnard
1, Avenue Jean Poulhes
31432 TOULOUSE CEDEX 4,FR
| | - Isabelle Naime
- Centre de Recherche de Croissy
Institut de Recherche Servier78290 Croissy-sur-Seine,FR
| | - Marie Françoise Simon
- Unité de recherche sur les obésités
INSERM : U586 IFR31Université Paul Sabatier - Toulouse IIIInstitut Louis Bugnard
1, Avenue Jean Poulhes
31432 TOULOUSE CEDEX 4,FR
| | - Marianne Rodriguez
- Centre de Recherche de Croissy
Institut de Recherche Servier78290 Croissy-sur-Seine,FR
| | - Jérémie Boucher
- Unité de recherche sur les obésités
INSERM : U586 IFR31Université Paul Sabatier - Toulouse IIIInstitut Louis Bugnard
1, Avenue Jean Poulhes
31432 TOULOUSE CEDEX 4,FR
| | - Ivan Tack
- Pharmacologie Moleculaire et Physiopathologie Renale
INSERM : U388 IFR31Université Paul Sabatier - Toulouse IIIInstitut Louis Bugnard
31432 TOULOUSE CEDEX 4,FR
| | - Stéphane Gesta
- Unité de recherche sur les obésités
INSERM : U586 IFR31Université Paul Sabatier - Toulouse IIIInstitut Louis Bugnard
1, Avenue Jean Poulhes
31432 TOULOUSE CEDEX 4,FR
| | - Pascale Chomarat
- Centre de Recherche de Croissy
Institut de Recherche Servier78290 Croissy-sur-Seine,FR
| | | | | | - Jean Pierre Galizzi
- Centre de Recherche de Croissy
Institut de Recherche Servier78290 Croissy-sur-Seine,FR
| | - Philippe Valet
- Unité de recherche sur les obésités
INSERM : U586 IFR31Université Paul Sabatier - Toulouse IIIInstitut Louis Bugnard
1, Avenue Jean Poulhes
31432 TOULOUSE CEDEX 4,FR
| | - Jean A. Boutin
- Centre de Recherche de Croissy
Institut de Recherche Servier78290 Croissy-sur-Seine,FR
| | - Jean Sébastien Saulnier-Blache
- Unité de recherche sur les obésités
INSERM : U586 IFR31Université Paul Sabatier - Toulouse IIIInstitut Louis Bugnard
1, Avenue Jean Poulhes
31432 TOULOUSE CEDEX 4,FR
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44
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Gijsbers R, Aoki J, Arai H, Bollen M. The hydrolysis of lysophospholipids and nucleotides by autotaxin (NPP2) involves a single catalytic site. FEBS Lett 2003; 538:60-4. [PMID: 12633853 DOI: 10.1016/s0014-5793(03)00133-9] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Autotaxin (NPP2) is a tumor cell motility-stimulating factor that displays both a nucleotide pyrophosphatase/phosphodiesterase activity and a recently described lysophospholipase D activity. The hydrolysis of nucleotides is a metal-assisted reaction that occurs via a nucleotidylated threonine in the catalytic site. We show here that the catalytic site threonine and the metal-coordinating residues are also essential for the hydrolysis of lysophospholipids. In comparing the substrate specificity of NPP2 and the closely related NPP1 and NPP3, we found that only NPP2 displayed a lysophospholipase D activity, whereas NPP1 and NPP3 had a much higher nucleotide pyrophosphatase activity.
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Affiliation(s)
- Rik Gijsbers
- Afdeling Biochemie, Faculteit Geneeskunde, University of Leuven, Herestraat 49, B-3000 Leuven, Belgium
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45
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Yang SY, Lee J, Park CG, Kim S, Hong S, Chung HC, Min SK, Han JW, Lee HW, Lee HY. Expression of autotaxin (NPP-2) is closely linked to invasiveness of breast cancer cells. Clin Exp Metastasis 2003; 19:603-8. [PMID: 12498389 DOI: 10.1023/a:1020950420196] [Citation(s) in RCA: 137] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Autotaxin (ATX), originally isolated from human melanoma cells, is a novel metastasis-enhancing motogen and angiogenesis factor. In the present study, we compared the expression level of ATX mRNA between normal and breast cancer tissues and found that the expression of ATX mRNA was closely linked to invasiveness of cancer cells. Reverse transcriptase-polymerase chain reaction (RT-PCR) and immunohistochemical analysis showed higher cellular ATX mRNA expression in the cancer than normal breast tissues. MDA-MB-435S breast cancer cells, expressing higher amount of ATX mRNA, showed greater relative invasiveness to fibroblast-conditioned medium (FCM) than MCF7, MDA-MB-231, and HBL-100 breast cancer cells. Furthermore, ATX-transfected MCF7 cells showed increased motility and invasiveness than vector-transfected MCF7 cells. Collectively, our results suggest that the expression of ATX is closely linked to the invasiveness of breast cancer cells.
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Affiliation(s)
- So Young Yang
- College of Medicine, Konyang University, Nonsan, Korea
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Jung ID, Lee J, Yun SY, Park CG, Choi WS, Lee HW, Choi OH, Han JW, Lee HY. Cdc42 and Rac1 are necessary for autotaxin-induced tumor cell motility in A2058 melanoma cells. FEBS Lett 2002; 532:351-6. [PMID: 12482591 DOI: 10.1016/s0014-5793(02)03698-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Autotaxin (ATX) is a strong motogen that can increase invasiveness and angiogenesis. In the present study, we investigated the signal transduction mechanism of ATX-induced tumor cell motility. Unlike N19RhoA expressing cells, the cells expressing N17Cdc42 or N17Rac1 showed reduced motility against ATX. ATX activated Cdc42 and Rac1 and increased complex formation between these small G proteins and p21-activated kinase (PAK). Furthermore, ATX phosphorylated focal adhesion kinase (FAK) that was not shown in cells expressing dominant negative mutants of Cdc42 or Rac1. Collectively, these data strongly indicate that Cdc42 and Rac1 are essential for ATX-induced tumor cell motility in A2058 melanoma cells, and that PAK and FAK might be also involved in the process.
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Affiliation(s)
- In Duk Jung
- College of Medicine, Konyang University, 320-711, Nonsan, South Korea
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Umezu-Goto M, Kishi Y, Taira A, Hama K, Dohmae N, Takio K, Yamori T, Mills GB, Inoue K, Aoki J, Arai H. Autotaxin has lysophospholipase D activity leading to tumor cell growth and motility by lysophosphatidic acid production. J Cell Biol 2002; 158:227-33. [PMID: 12119361 PMCID: PMC2173129 DOI: 10.1083/jcb.200204026] [Citation(s) in RCA: 751] [Impact Index Per Article: 34.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Autotaxin (ATX) is a tumor cell motility-stimulating factor, originally isolated from melanoma cell supernatants. ATX had been proposed to mediate its effects through 5'-nucleotide pyrophosphatase and phosphodiesterase activities. However, the ATX substrate mediating the increase in cellular motility remains to be identified. Here, we demonstrated that lysophospholipase D (lysoPLD) purified from fetal bovine serum, which catalyzes the production of the bioactive phospholipid mediator, lysophosphatidic acid (LPA), from lysophosphatidylcholine (LPC), is identical to ATX. The Km value of ATX for LPC was 25-fold lower than that for the synthetic nucleoside substrate, p-nitrophenyl-tri-monophosphate. LPA mediates multiple biological functions including cytoskeletal reorganization, chemotaxis, and cell growth through activation of specific G protein-coupled receptors. Recombinant ATX, particularly in the presence of LPC, dramatically increased chemotaxis and proliferation of multiple different cell lines. Moreover, we demonstrate that several cancer cell lines release significant amounts of LPC, a substrate for ATX, into the culture medium. The demonstration that ATX and lysoPLD are identical suggests that autocrine or paracrine production of LPA contributes to tumor cell motility, survival, and proliferation. It also provides potential novel targets for therapy of pathophysiological states including cancer.
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Affiliation(s)
- Makiko Umezu-Goto
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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Lee HY, Bae GU, Jung ID, Lee JS, Kim YK, Noh SH, Stracke ML, Park CG, Lee HW, Han JW. Autotaxin promotes motility via G protein-coupled phosphoinositide 3-kinase gamma in human melanoma cells. FEBS Lett 2002; 515:137-40. [PMID: 11943209 DOI: 10.1016/s0014-5793(02)02457-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Autotaxin (ATX), an exo-nucleotide pyrophosphatase and phosphodiesterase, stimulates tumor cell motility at sub-nanomolar levels and augments invasiveness and angiogenesis. We investigated the role of G protein-coupled phosphoinositide 3-kinase gamma (PI3Kgamma) in ATX-mediated tumor cell motility stimulation. Pretreatment of human melanoma cell line A2058 with wortmannin or LY294002 inhibited ATX-induced motility. ATX increased the PI3K activity in p110gamma, but not p85, immunoprecipitates. This effect was abrogated by PI3K inhibitors or inhibited by pertussis toxin. Furthermore, stimulation of tumor cell motility by ATX was inhibited by catalytically inactive form of PI3Kgamma, strongly indicating the crucial role of PI3Kgamma for ATX-mediated motility in human melanoma cells
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Affiliation(s)
- Hoi Young Lee
- College of Medicine, Konyang University, 320-711, Nonsan, South Korea
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Lee J, Jung ID, Nam SW, Clair T, Jeong EM, Hong SY, Han JW, Lee HW, Stracke ML, Lee HY. Enzymatic activation of autotaxin by divalent cations without EF-hand loop region involvement. Biochem Pharmacol 2001; 62:219-24. [PMID: 11389881 DOI: 10.1016/s0006-2952(01)00658-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Autotaxin (ATX) is a recently described member of the nucleotide pyrophosphatase/phosphodiesterase (NPP) family of proteins with potent tumor cell motility-stimulating activity. Like other NPPs, ATX is a glycoprotein with peptide sequences homologous to the catalytic site of bovine intestinal alkaline phosphodiesterase (PDE) and the loop region of an EF-hand motif. The PDE active site of ATX has been associated with the motility-stimulating activity of ATX. In this study, we examined the roles of the EF-hand loop region and of divalent cations on the enzymatic activities of ATX. Ca(2+) or Mg(2+) was each demonstrated to increase the PDE activity of ATX in a concentration-dependent manner, whereas incubation of ATX with chelating agents abolished this activity, indicating a requirement for divalent cations. Non-linear regression analysis of enzyme kinetic data indicated that addition of these divalent cations increases reaction velocity predominantly through an effect on V(max.) Three mutant proteins, Ala(740)-, Ala(742)-, and Ala(751)-ATX, in the EF-hand loop region of ATX had enzymatic activity comparable to that of the wild-type protein. A deletion mutation of the entire loop region resulted in slightly reduced PDE activity but normal motility-stimulating activity. However, the PDE activity of this same deletion mutant remained sensitive to augmentation by cations, strongly implying that cations exert their effect by interactions outside of the EF-hand loop region.
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Affiliation(s)
- J Lee
- College of Medicine, Konyang University, Nonsan 320-711, South Korea
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Bollen M, Gijsbers R, Ceulemans H, Stalmans W, Stefan C. Nucleotide pyrophosphatases/phosphodiesterases on the move. Crit Rev Biochem Mol Biol 2001; 35:393-432. [PMID: 11202013 DOI: 10.1080/10409230091169249] [Citation(s) in RCA: 228] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Nucleotide pyrophosphatases/phosphodiesterases (NPPs) release nucleoside 5'-monophosphates from nucleotides and their derivatives. They exist both as membrane proteins, with an extracellular active site, and as soluble proteins in body fluids. The only well-characterized NPPs are the mammalian ecto-enzymes NPP1 (PC-1), NPP2 (autotaxin) and NPP3 (B10; gp130(RB13-6)). These are modular proteins consisting of a short N-terminal intracellular domain, a single transmembrane domain, two somatomedin-B-like domains, a catalytic domain, and a C-terminal nuclease-like domain. The catalytic domain of NPPs is conserved from prokaryotes to mammals and shows remarkable structural and catalytic similarities with the catalytic domain of other phospho-/sulfo-coordinating enzymes such as alkaline phosphatases. Hydrolysis of pyrophosphate/phosphodiester bonds by NPPs occurs via a nucleotidylated threonine. NPPs are also known to auto(de)phosphorylate this active-site threonine, a process accounted for by an intrinsic phosphatase activity, with the phosphorylated enzyme representing the catalytic intermediate of the phosphatase reaction. NPP1-3 have been implicated in various processes, including bone mineralization, signaling by insulin and by nucleotides, and the differentiation and motility of cells. While it has been established that most of these biological effects of NPPs require a functional catalytic site, their physiological substrates remain to be identified.
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Affiliation(s)
- M Bollen
- Afdeling Biochemie, Faculteit Geneeskunde, Katholieke Universiteit, Leuven, Belgium
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