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Kasai T, Nakanishi T, Ohno Y, Shimada H, Nakamura Y, Arakawa H, Tamai I. Role of OATP2A1 in PGE(2) secretion from human colorectal cancer cells via exocytosis in response to oxidative stress. Exp Cell Res 2016; 341:123-31. [PMID: 26850138 DOI: 10.1016/j.yexcr.2016.02.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Revised: 01/29/2016] [Accepted: 02/01/2016] [Indexed: 12/30/2022]
Abstract
Chronic inflammation induced by reactive oxygen species is associated with increased risk of developing colorectal cancer (CRC), and prostaglandin E2 (PGE2), which serves as a key mediator of inflammatory responses, plays an important role in CRC initiation and progression. Therefore, in the present study, we aimed to investigate the role of prostaglandin transporter OATP2A1/SLCO2A1 in the changes of PGE2 disposition in CRC cells in response to oxidative stress. H2O2 induced translocation of cytoplasmic OATP2A1 to plasma membranes in LoVo and COLO 320DM cells, but not in Caco-2 cells. The shift of subcellular OATP2A1 was abolished in the presence of anti-oxidant N-acetyl-L-cysteine or an inhibitor of protein kinase C, which evokes exocytosis. Exposure of LoVo cells to H2O2 caused an increase in the amount of extracellular PGE2 without changing the sum of intra- and extracellular PGE2. OATP2A1 knockdown decreased extracellular PGE2 in LoVo cells. In addition, extracellular PGE2 was significantly reduced by exocytosis inhibitor cytochalasin D, suggesting that H2O2-induced PGE2 release occurs in an exocytotic manner. Furthermore, mRNA expression of vascular endothelial growth factor (VEGF) was significantly reduced in LoVo cells by knockdown of OATP2A1. These results suggest that cytoplasmic OATP2A1 likely facilitates PGE2 loading into suitable intracellular compartment(s) for efficient exocytotic PGE2 release from CRC cells exposed to oxidative stress.
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Affiliation(s)
- Taku Kasai
- Faculty of Pharmaceutical Science, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
| | - Takeo Nakanishi
- Faculty of Pharmaceutical Science, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
| | - Yasuhiro Ohno
- Faculty of Pharmaceutical Science, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
| | - Hiroaki Shimada
- Faculty of Pharmaceutical Science, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
| | - Yoshinobu Nakamura
- Faculty of Pharmaceutical Science, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
| | - Hiroshi Arakawa
- Faculty of Pharmaceutical Science, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan
| | - Ikumi Tamai
- Faculty of Pharmaceutical Science, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan.
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MC-12, an annexin A1-based peptide, is effective in the treatment of experimental colitis. PLoS One 2012; 7:e41585. [PMID: 22844504 PMCID: PMC3402399 DOI: 10.1371/journal.pone.0041585] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2012] [Accepted: 06/25/2012] [Indexed: 12/11/2022] Open
Abstract
Annexin A1 (ANXA1) inhibits NF-κB, a key regulator of inflammation, the common pathophysiological mechanism of inflammatory bowel diseases (IBD). MC-12, an ANXA1-based tripeptide, suppresses NF-κB activation. Here, we determined the efficacy of MC-12 in the control of IBD. Mice with colitis induced by dextran sodium sulfate (DSS) or 2,4,6-trinitro benzene sulfonic acid (TNBS) were treated with various doses of MC-12 administered intraperitoneally, orally or intrarectally. We determined colon length and the histological score of colitis, and assayed: in colon tissue the levels of TNF-α, IFN-γ, IL-1β, IL-6 and IL-10 by RT-PCR; prostaglandin E2 (PGE2), cytoplasmic phospholipase A2 (cPLA2) and myeloperoxidase by immunoassay; and COX-2 and NF- κB by immunohistochemistry; and in serum the levels of various cytokines by immunoassay. In both models MC-12: reversed dose-dependently colonic inflammation; inhibited by up to 47% myeloperoxidase activity; had a minimal effect on cytoplasmic phospholipase A2; reduced significantly the induced levels of TNF-α, IFN-γ, IL-1β, IL-6 and IL-10, returning them to baseline. DSS and TNBS markedly activated NF-κB in colonic epithelial cells and MC-12 decreased this effect by 85.8% and 72.5%, respectively. MC-12 had a similar effect in cultured NCM460 normal colon epithelial cells. Finally, MC-12 suppressed the induction of COX-2 expression, the level of PGE2 in the colon and PGE2 metabolite in serum. In conclusion, MC-12, representing a novel class of short peptide inhibitors of NF-κB, has a strong effect against colitis in two preclinical models recapitulating features of human IBD. Its mechanism of action is complex and includes pronounced inhibition of NF-κB. MC-12 merits further development as an agent for the control of IBD.
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Christerson U, Keita AV, Söderholm JD, Gustafson-Svärd C. Potential role of protease-activated receptor-2-stimulated activation of cytosolic phospholipase A(2) in intestinal myofibroblast proliferation: Implications for stricture formation in Crohn's disease. J Crohns Colitis 2009; 3:15-24. [PMID: 21172243 DOI: 10.1016/j.crohns.2008.10.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/08/2008] [Revised: 09/17/2008] [Accepted: 10/01/2008] [Indexed: 01/25/2023]
Abstract
BACKGROUND AND AIMS Myofibroblast hyperplasia contributes to muscularis mucosae thickening and stricture formation in Crohn's disease (CD). Protease-activated receptor-2 (PAR-2) and cytosolic phospholipase A(2) (cPLA(2)) are known regulators of cell growth, but their significance in intestinal myofibroblast proliferation remain to be elucidated. The principle aims of the present study were to investigate if PAR-2 is expressed in the expanded muscularis mucosa in ileal CD specimens, if inflammatory cytokines may stimulate PAR-2 expression in intestinal myofibroblasts, and if PAR-2 and cPLA(2) may regulate intestinal myofibroblast growth. METHODS Immunohistochemistry was used for detection of PAR-2 in ileal CD specimens. Studies on PAR-2 expression, PLA(2) activation and cell growth were performed in a human intestinal myofibroblast cell line, CCD-18Co. PAR-2 expression was investigated by RT-PCR and immunocytochemistry. PLA(2) activity was analyzed by quantification of released (14)C-arachidonic acid ((14)C-AA). Cell growth was examined by (3)H-thymidine incorporation and cell counting. RESULTS The thickened muscularis mucosae of the CD specimens showed strong PAR-2 expression. In cultured myofibroblasts, tumor necrosis factor-α (TNF-α) up-regulated PAR-2 mRNA and protein, and potentiated PAR-2-stimulated (14)C-AA release by two known PAR-2 activators, trypsin and SLIGRL-NH(2). The release of (14)C-AA was dependent on cPLA(2). Trypsin stimulated the proliferation of serum-starved cells, and inhibition of cPLA(2) reduced normal cell growth and abolished the growth-promoting effect of trypsin. CONCLUSIONS The results suggest that PAR-2-mediated cPLA(2) activation might be of importance in intestinal myofibroblast proliferation. The results also point to the possibility that PAR-2 up-regulation by inflammatory cytokines, like TNF-α, may modulate this effect.
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Affiliation(s)
- Ulrika Christerson
- School of Pure and Applied Natural Sciences, University of Kalmar, SE-391 82 Kalmar, Sweden
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Bax DA, Siersema PD, Van Vliet AHM, Kuipers EJ, Kusters JG. Molecular alterations during development of esophageal adenocarcinoma. J Surg Oncol 2005; 92:89-98; discussion 99. [PMID: 16231373 DOI: 10.1002/jso.20353] [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: 12/17/2022]
Abstract
The incidence of esophageal adenocarcinoma has risen significantly over the last decades. During esophageal carcinogenesis many molecular alterations occur that disrupt essential cellular processes, directing the cell to a rapidly proliferating, immortal state. The chronic inflammation that is present in Barrett's esophagus creates an environment in which such molecular alterations are both induced and tolerated. Here, the novel insights in the molecular mechanisms that underlie the development of esophageal adenocarcinoma are reviewed, focusing on the role of inflammation, angiogenesis, apoptosis inhibition, loss of cell cycle control, and loss of cell-cell adhesion. These novel developments will open new perspectives for diagnosis, treatment, and prevention of esophageal adenocarcinoma.
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Affiliation(s)
- Dorine A Bax
- Department of Gastroenterology and Hepatology, Erasmus MC - University Medical Center Rotterdam, Rotterdam, The Netherlands
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Jobin C, Morteau O, Han DS, Balfour Sartor R. Specific NF-kappaB blockade selectively inhibits tumour necrosis factor-alpha-induced COX-2 but not constitutive COX-1 gene expression in HT-29 cells. Immunology 1998; 95:537-43. [PMID: 9893042 PMCID: PMC1364349 DOI: 10.1046/j.1365-2567.1998.00646.x] [Citation(s) in RCA: 118] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cyclo-oxygenase (COX) is the key regulatory enzyme of the prostaglandin/eicosanoid pathway. While COX-1 is mostly constitutively expressed, the COX-2 isoform is inducible by proinflammatory cytokines. We used an adenoviral vector containing an NF-kappaB super-repressor (Ad5IkappaB) to investigate the role of NF-kappaB in tumour necrosis factor-alpha (TNF-alpha)-mediated COX-2 gene expression in a colonic epithelial cell line. COX-1 mRNA and protein were constitutively expressed in uninfected, control Ad5LacZ- or Ad5IkappaB-infected HT-29 cells with no apparent change following TNF-alpha exposure. COX-2 mRNA and protein expression was undetectable in unstimulated cells but was strongly up-regulated after TNF-alpha stimulation in uninfected and Ad5LacZ-infected HT-29 cells. This induction was prevented in Ad5IkappaB cells. TNF-alpha increased prostaglandin E2 production by 20-fold in Ad5LacZ-infected HT-29 cells compared with uninfected cells and was significantly inhibited in Ad5IkappaB-infected cells in agreement with the COX-2 mRNA findings. We conclude that NF-kappaB activation is critical in mediating COX-2, but not COX-1 gene expression in HT-29 cells. Selective inhibition of COX-2 expression with the NF-kappaB super-repressor may be useful in distinguishing the role of inducible versus constitutive prostaglandins in intestinal function and provides greater specificity than pharmacological inhibitors.
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Affiliation(s)
- C Jobin
- Departments of Medicine, Microbiology, Immunology and the Center for Gastrointestinal Biology and Disease, University of North Carolina, Chapel Hill, NC 27599, USA
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Thommesen L, Sjursen W, Gåsvik K, Hanssen W, Brekke OL, Skattebøl L, Holmeide AK, Espevik T, Johansen B, Lægreid A. Selective Inhibitors of Cytosolic or Secretory Phospholipase A2 Block TNF-Induced Activation of Transcription Factor Nuclear Factor-κB and Expression of ICAM-1. THE JOURNAL OF IMMUNOLOGY 1998. [DOI: 10.4049/jimmunol.161.7.3421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Abstract
TNF signaling mechanisms involved in activation of transcription factor NF-κB were studied in the human keratinocyte cell line HaCaT. We show that TNF-induced activation of NF-κB was inhibited by the well-known selective inhibitors of cytosolic phospholipase A2 (cPLA2): the trifluoromethyl ketone analogue of arachidonic acid (AACOCF3) and methyl arachidonyl fluorophosphate. The trifluoromethyl ketone analogue of eicosapentaenoic acid (EPACOCF3) also suppressed TNF-induced NF-κB activation and inhibited in vitro cPLA2 enzyme activity with a similar potency as AACOCF3. The arachidonyl methyl ketone analogue (AACOCH3) and the eicosapentanoyl analogue (EPACHOHCF3), which both failed to inhibit cPLA2 enzyme activity in vitro, had no effect on TNF-induced NF-κB activation. TNF-induced NF-κB activation was also strongly reduced in cells stimulated in the presence of the secretory PLA2 (sPLA2) inhibitors 12-epi-scalaradial and LY311727. Addition of excess arachidonic acid suppressed the inhibitory effect of 12-epi-scalaradial and LY311727. Moreover, both methyl arachidonyl fluorophosphate and 12-epi-scalaradial blocked TNF-mediated enhancement of expression of ICAM-1. Activation of NF-κB by IL-1β was markedly less sensitive to both cPLA2 and sPLA2 inhibitors. The results indicate that both cPLA2 and sPLA2 may be involved in the TNF signal transduction pathway leading to nuclear translocation of NF-κB and to NF-κB-activated gene expression in HaCaT cells.
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Affiliation(s)
- Liv Thommesen
- *UNIGEN–Center for Molecular Biology,
- †Department of Physiology and Biomedical Engineering,
| | - Wenche Sjursen
- *UNIGEN–Center for Molecular Biology,
- ‡Institute of Chemistry,
| | | | - Wenche Hanssen
- *UNIGEN–Center for Molecular Biology,
- §Institute of Botany,
| | | | - Lars Skattebøl
- #Department of Chemistry, University of Oslo, Oslo, Norway
| | | | - Terje Espevik
- ¶Institute of Cancer Research and Molecular Biology, Norwegian University of Science and Technology, and Department of Clinical Chemistry, Trondheim Regional Hospital, Trondheim, Norway; and
| | - Berit Johansen
- *UNIGEN–Center for Molecular Biology,
- §Institute of Botany,
| | - Astrid Lægreid
- *UNIGEN–Center for Molecular Biology,
- †Department of Physiology and Biomedical Engineering,
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Devor DC, Frizzell RA. Modulation of K+ channels by arachidonic acid in T84 cells. II. Activation of a Ca(2+)-independent K+ channel. THE AMERICAN JOURNAL OF PHYSIOLOGY 1998; 274:C149-60. [PMID: 9458723 DOI: 10.1152/ajpcell.1998.274.1.c149] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
We used single-channel recording techniques to identify and characterize a large-conductance, Ca(2+)-independent K+ channel in the colonic secretory cell line T84. In symmetric potassium gluconate, this channel had a linear current-voltage relationship with a single-channel conductance of 161 pS. Channel open probability (Po) was increased at depolarizing potentials. Partial substitution of bath K+ with Na+ indicated a permeability ratio of K+ to Na+ of 25:1. Channel Po was reduced by extracellular Ba2+. Event-duration analysis suggested a linear kinetic model for channel gating having a single open state and three closed states: C3<-->C2<-->C1<-->O. Arachidonic acid (AA) increased the Po of the channel, with an apparent stimulatory constant (Ks) of 1.39 microM. Neither channel open time (O) nor the fast closed time (C1) was affected by AA. In contrast, AA dramatically reduced mean closed time by decreasing both C3 and C2. The cis-unsaturated fatty acid linoleate increased Po also, whereas the saturated fatty acid myristate and the trans-unsaturated fatty acid elaidate did not affect Po. This channel is activated also by negative pressure applied to the pipette during inside-out recording. Thus we determined the effect of the stretch-activated channel blockers amiloride and Gd3+ on the K+ channel after activation by AA. Amiloride (2 mM) on the extracellular side reduced single-channel amplitude in a voltage-dependent manner, whereas Gd3+ (100 microM) had no effect on channel activity. Activation of this K+ channel may be important during stimulation of Cl- secretion by agonists that use AA as a second messenger (e.g., vasoactive intestinal polypeptide, adenosine) or during the volume regulatory response to cell swelling.
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Affiliation(s)
- D C Devor
- Department of Cell Biology and Physiology, University of Pittsburgh, Pennsylvania 15261, USA. dd2+@pitt.edu
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8
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Uptake of arachidonic acid from blood 2-lyso-phosphatidylcholine by extrahepatic tissues in vivo: An experimental study in the rat. J Nutr Biochem 1997. [DOI: 10.1016/s0955-2863(97)00114-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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9
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Walton M, Sirimanne E, Williams C, Gluckman PD, Keelan J, Mitchell MD, Dragunow M. Prostaglandin H synthase-2 and cytosolic phospholipase A2 in the hypoxic-ischemic brain: role in neuronal death or survival? BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 1997; 50:165-70. [PMID: 9406931 DOI: 10.1016/s0169-328x(97)00181-2] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The breakdown of membrane phospholipids and subsequent arachidonic acid metabolism to prostanoids is a well-documented brain response to cerebral ischemia. To further elucidate the components of this signal transduction pathway, immunocytochemistry was used to determine the levels of two potentially important enzymes, cytosolic phospholipase A2 (cPLA2) and prostaglandin H synthase-2 (PGHS-2), in the immature rat brain following moderate unilateral hypoxic-ischemia (HI). The CA1 pyramidal cells of the hippocampus which undergo delayed neuronal death on the injured side following HI demonstrated a significant induction of PGHS-2 immunoreactivity 48 h post-insult. However, a consistent increase in PGHS-2 was also evident in the resistant dentate granule cells at an earlier time point. Although PGHS-2 is present in both susceptible and resistant cell populations following HI, the possibility remains that divergence further down-stream in the pathway is responsible for selective vulnerability. In contrast to the neuronal PGHS-2 expression, cPLA2 immunoreactivity appears to be of glial origin with increases in and around the CAI-2 pyramidal cell layer at the 72-168-h time points. These results suggest that prostanoids are likely to serve important roles in HI brain damage and repair in infant brain.
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Affiliation(s)
- M Walton
- Department of Pharmacology, Faculty of Medicine and Health Science, University of Auckland, New Zealand
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Soydan AS, Gaffen JD, Weech PK, Tremblay NM, Kargman S, O'Neill G, Bennett A, Tavares IA. Cytosolic phospholipase A2, cyclo-oxygenases and arachidonate in human stomach tumours. Eur J Cancer 1997; 33:1508-12. [PMID: 9337697 DOI: 10.1016/s0959-8049(97)00168-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Human stomach tumours usually form more prostaglandins (PGs) than their associated normal mucosa/submucosa, but the mechanisms are not fully understood. The key enzymes are cytosolic phospholipase A2 (cPLA2, Mr 85,000) and the cyclo-oxygenases (COXs) which exist in constitutive (COX-1) and inducible forms (COX-2). In human stomach tumours and associated macroscopically normal tissues, we determined the fatty acid composition by gas chromatography, amounts of cPLA2, COX-1 and COX-2 by immunoblotting with specific antibodies and cPLA2 enzyme activity using a tritiated substrate. Although compared to normal mucosa there was less arachidonate in tumours (P < 0.05), the arachidonate/total fatty acid ratio was higher. Mean amounts of cPLA2 and COX-1 and cPLA2 activity were similar in tumours and normal mucosa. However, substantial amounts of COX-2 were found in the tumours but not in the mucosa, which may explain why many gastric tumours form increased amounts of PGs.
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Affiliation(s)
- A S Soydan
- Academic Department of Surgery, Rayne Institute, King's College School of Medicine and Dentistry, London, U.K
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Gustafson-Svärd C, Lilja I, Hallböök O, Sjödahl R. Cyclo-oxygenase and colon cancer: clues to the aspirin effect? Ann Med 1997; 29:247-52. [PMID: 9240630 DOI: 10.3109/07853899708999342] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Epidemiological and experimental studies indicate an inverse relationship between the risk of colon cancer development and intake of aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs). All NSAIDs are known inhibitors of cyclo-oxygenase, the enzyme responsible for converting arachidonic acid to prostaglandins. Prostaglandins have been implicated in the pathogenesis of colon cancer and it has been suggested that the preventive effect of NSAIDs is due to inhibition of cyclo-oxygenase activity. Cyclo-oxygenase exists in two different isoforms, cyclo-oxygenase-1 and cyclo-oxygenase-2, and data obtained during the last few years have suggested that cyclo-oxygenase-2 might be involved in both human and experimental colon carcinogenesis. The purpose of this review is to provide an update on recent studies regarding cyclo-oxygenase, in particular cyclo-oxygenase-2, in relation to colon cancer in humans and in experimental models.
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Affiliation(s)
- C Gustafson-Svärd
- Clinical Research Centre, Department of Biomedicine and Natural Sciences, The Baltic International School of Public Health (BIH), Karlskrona, Sweden.
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