• Title/Summary/Keyword: Cyclooxygenase 2

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Phorbol Ester TPA Modulates Chemoresistance in the Drug Sensitive Breast Cancer Cell Line MCF-7 by Inducing Expression of Drug Efflux Transporter ABCG2

  • Kalalinia, Fatemeh;Elahian, Fatemeh;Hassani, Mitra;Kasaeeian, Jamal;Behravan, Javad
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.6
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    • pp.2979-2984
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    • 2012
  • Recent studies have indicated a link between levels of cyclooxygenase-2 (COX-2) and development of the multidrug resistance (MDR) phenotype. The ATP-binding cassette sub-family G member 2 (ABCG2) is a major MDR-related transporter protein that is frequently overexpressed in cancer patients. In this study, we aimed to evaluate any positive correlation between COX-2 and ABCG2 gene expression using the COX-2 inducer 12-O-tetradecanoylphorbol-13-acetate (TPA) in human breast cancer cell lines. ABCG2 mRNA and protein expression was studied using real-time RT-PCR and flow cytometry, respectively. A significant increase of COX-2 mRNA expression (up to 11-fold by 4 h) was induced by TPA in MDA-MB-231 cells, this induction effect being lower in MCF-7 cells. TPA caused a considerable increase up to 9-fold in ABCG2 mRNA expression in parental MCF-7 cells, while it caused a small enhancement in ABCG2 expression up to 67 % by 4 h followed by a time-dependent decrease in ABCG2 mRNA expression in MDA-MB-231 cells. TPA treatment resulted in a slight increase of ABCG2 protein expression in MCF-7 cells, while a time-dependent decrease in ABCG2 protein expression was occurred in MDA-MB-231 cells. In conclusion, based on the observed effects of TPA in MDA-Mb-231 cells, it is proposed that TPA up-regulates ABCG2 expression in the drug sensitive MCF-7 breast cancer cell line through COX-2 unrelated pathways.

Cyclooxygenase-2 Expression in Invasive Breast Carcinomas of No Special Type and Correlation with Pathological Profiles Suggest a Role in Tumorigenesis Rather than Cancer Progression

  • Misron, Nurul Akmar;Looi, Lai-Meng;Mustapha, Nik Raihan Nik
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.4
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    • pp.1553-1558
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    • 2015
  • Background: COX-2 has been shown to play an important role in the development of breast cancer and increased expression has been mooted as a poor prognostic factor. The purpose of this study was to investigate the relationship between COX-2 immunohistochemical expression and known predictive and prognostic factors in breast cancer in a routine diagnostic histopathology setting. Materials and Methods: Formalin-fixed paraffin-embedded tumour tissue of 144 no special type (NST) invasive breast carcinomas histologically diagnosed between January 2009 and December 2012 in Hospital Sultanah Bahiyah, Alor Setar, Kedah were immunostained with COX-2 antibody. COX-2 overexpression was analysed against demographic data, hormone receptor status, HER2-neu overexpression, histological grade, tumour size and lymph node status. Results: COX-2 was overexpressed in 108/144 (75%) tumours and was significantly more prevalent (87%) in hormone receptor-positive tumours. There was no correlation between COX-2 overexpression and HER2/neu status. Triple negative cancers had the lowest prevalence (46%) (p<0.05). A rising trend of COX-2 overexpression with increasing age was observed. There was a significant inverse relationship with tumour grade (p<0.05), prevalences being 94%, 83% and 66% in grades 1, 2 and 3 tumours, respectively. A higher prevalence of COX-2 overexpression in smaller size tumours was observed but this did not reach statistical significance. There was no relationship between COX-2 expression and lymph node status. Conclusions: This study did not support the generally held notion that COX-2 overexpression is linked to poor prognosis, rather supporting a role in tumorigenesis. Larger scale studies with outcome data and basic studies on cancer pathogenetic pathways will be required to cast further light on whether COX-2 inhibitors would have clinical utility in cancer prevention or blockage of cancer progression. In either setting, the pathological assessment for COX-2 overexpression in breast cancers would have an important role in the selection of cancer patients for personalized therapy with COX-2 inhibitors.

Phospholipase D isozymes mediate epigallocatechin gallate-induced cyclooxygenase-2 expression in astrocyte cells

  • Kim, Shi-Yeon;Min, Kyoung-Jin;Joe, Eun-Hye;Min, Do-Sik
    • Proceedings of the Korean Society of Plant Biotechnology Conference
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    • 2004.10a
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    • pp.74-79
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    • 2004
  • Little is known about the effect of epigallocatechin-3 gallate (ESCG), a major constituent of green tea, on the expression of cyclooxygenase (COX)-2. Here, we studied the role of phospholipase D (PLD) isozymes in EGCG-induced COX-2 expression. Stimulation of human astrocytoma cells (U87) with EGCG induced formation of phosphatidylbutanol, a specific product of PLD activity, and synthesis of COX-2protein and its product, prostaglandin $E_2$ ($PGE_2$). Pretreatment of cells with 1-butanol, but not 3-butanol, suppressed EGCG-induced COX-2 expression and $PGE_2$ synthesis. Furthermore, evidence that PLD was involved in EGCG-induced COX-2 expression w3s provided by the observations that COX-2 expression was stimulated by over-expression of PLD1 or PLD2 isozymes and treatment with phosphatidic acid(PA), and that prevention of PA dephosphorylation by 1-propranolol significantly potentiated COX-2expression Induced by EGCG. EGCG induced activation of p38 mitogen-activated protein kinase (p38MAPK), and specific Inhibition of p38 MAPK dramatically abolished EGCG-Induced PLD activation, COX-2 expression, and $PGE_2$ formation. Moreover, protein kinase C (PKC) inhibition suppressed EGCG-induced p38 MAPK activation, COX-2 expression, and $PGE_2$ accumulation. The same pathways as those obtained in the astrocytoma cells were active in primary rat astrocytes, suggesting the relevance of the findings. Collectively, our results demonstrate for the first time that PLD isozymes mediate EGCG-induced COX-2 expression through PKC and p38 in immortalized astroglial line and normal astrocyte cells.

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Regulation of Bcl-2 Family and Cyclooxygenases by Furanoterpenoids Isolated from a Marine Sponge Swcotragus nt. in Human Lung Cancer A549 Cells. (인체폐암세포의 Bcl-2 family 및 cyclooxygenases의 발현에 미치는 해면동물 Sarcotragus sp. 유래 furanoterpenoids의 영향)

  • 최영현;최혜정;김남득;정지형
    • Journal of Life Science
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    • v.14 no.3
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    • pp.445-452
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    • 2004
  • We investigated the cytotoxic effects of seven furanoterpenoids 〔sarcotin A, epi-sarcotin A, ircinin-1, epi-sarcotrine B, sarcotin I, (8E, l3Z, 20Z)-strobilinin/(7E,l3Z, 20Z)-felixinin and (7E,12E,18R,20Z)-variabilin〕 isolated from the sponge Sarcotragus sp. (the order Dictyoceratida) on the growth of A549 human lung carcinoma cells. MTT data revealed that sarcotin A and (7E,12E,18R,20Z)-variabilin exhibited higher potencies on the anti-proliferative activities than the other compounds in A549 cells. The growth inhibition by treatment with compounds (especially epi-sarcotin A, ircinin-1 and epi-sarcotrine B) were associated with the induction of apoptotic cell death through the concentration-dependent increase of Bax/Bcl-2 ratio in a p53-dependent or independent pathway Additionally, epi-sarcotin A and ircinin-1 strongly inhibited the levels of cyclooxygenase (COX)-2 expression without alteration of COX-1. Taken together, the results suggest that the furanoterpenoids from the marine sponge have strong potentials as candidates for anti-cancer drugs.

Suppression of Transglutaminase-2 is Involved in Anti-Inflammatory Actions of Glucosamine in 12-O-Tetradecanoylphorbol-13-Acetate-Induced Skin Inflammation

  • Park, Mi-Kyung;Cho, Sun-A;Lee, Hye-Ja;Lee, Eun-Ji;Kang, June-Hee;Kim, You-Lee;Kim, Hyun-Ji;Oh, Seung-Hyun;Choi, Chang-Sun;Lee, Ho;Kim, Soo-Youl;Lee, Chang-Hoon
    • Biomolecules & Therapeutics
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    • v.20 no.4
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    • pp.380-385
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    • 2012
  • Glucosamine (GS) is well known for the treatment of inflammation. However, the mechanism and efficacy of GS for skin inflammation are unclear. The aim of this study was to evaluate the effects and mechanism of GS in the mouse 12-O-tetradecanoyl 13-acetate (TPA)-induced ear edema model. TPA-induced ear edema was evoked in ICR or transglutaminase 2 (Tgase-2) (-/-) mice. GS was administered orally (10-100 mg/kg) or topically (0.5-2.0 w/v %) prior to TPA treatment. Orally administered GS at 10 mg/kg showed a 76 or 57% reduction in ear weight or myeloperoxidase, respectively, and a decreased expression of cyclooxygenase-2 (COX-2), NF-${\kappa}B$ and Tgase-2 in TPA-induced ear edema by western blot and immunohistochemistry. Role of Tgase-2 in TPA ear edema is examined using Tgase-2 (-/-) mice and TPA did not induce COX-2 expression in ear of Tgase-2 (-/-) mice. These observations suggested that Tgase-2 is involved in TPA-induced COX-2 expression in the inflamed ear of mice and antiinflammatory effects of glucosamine is mediated through suppression of Tgase-2 in TPA ear edema.

The Effects of Cyclooxygenase-2(COX-2) Inhibitor on COX-2 and Prostaglandin E2 Expression in Ovalbumin Induced Early Phase Bronchoconstriction of Rats (Ovalbumin으로 유발된 백서의 즉시형 기관지 수축 반응에서 Cyclooxygenase-2(COX-2) 발현 양상 및 혈중 프로스타글란딘 E2 농도와 COX-2 억제제의 효과)

  • Lee, Sung-Yong;Lee, Sin-Hyung;Jung, Ki-Hwan;Kim, Byung-Gyu;Jung, Hae-Chul;Kim, Kyung-Kyu;Kwon, Young-Hwan;Kim, Ja-Hyeong;Lee, Ju-Han;Lee, Sang-Youb;Cho, Jae-Yoen;Shim, Jae-Joeng;In, Kwang-Ho;Yoo, Se-Hwa;Kang, Kyung-Ho
    • Tuberculosis and Respiratory Diseases
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    • v.48 no.2
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    • pp.191-202
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    • 2000
  • Background: Bronchial asthma is characterized by airway hyperresponsiveness(BHR) and inflammation. The cyclooxygenase(COX) is believed to be one of the important enzymes in these inflammatory reactions. Recently, the COX was divided into two isoforms, COX1 and COX2. COX2 is induced by lipopolysaccharide and some cytokines at the inflammation site. Prostaglandin E2(PGE2), produced from COX2, may affect airway inflammation. The purpose of this study is to evaluate the effect of COX2 inhibitor on COX2 expression, plasma PGE2, airway resistance and histologic finding in an animal asthma model. Methods : Sprague-Dawley rats were divided into 3 groups. The normal control group did not receive any treatment, but the asthma control group was sensitized by ovalbumin but not treated with the COX2 inhibitor(nimesulide, Mesulid$^{(R)}$). The treatment group was sensitized and treated with nimesulide. Specific airway resistance(sRaw) before and after nimesulide ingestion was investigated. The PGE2 level in the plasma was examined and COX2 immunogold-silver stain on lung tissue was performed. Results: sRaw and eosionophilic infiltration on airway, which increased in the asthma control group, was compared to normal control(p=0.014). However, there was no difference in eosinophilic infiltration between asthma control and treatment groups(p=0.408) and no difference in COX2 expression on bronchiolar epithelium among the three groups. Plasma PGE2 levels were not statically different among the three groups. Conclusion: The role of COX2 in the allergen-induced BHR was not significant The effect of nimesulide was not observed on BHR, COX2 expression, and plasma PGE2 level. Therefore, COX2 may not be a major substance of allergic asthma.

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Effects of Armeniacae Semen and Amygdalin on Prostaglandin E2 Synthesis and Nitric Oxide Production (행인(杏仁)과 Amygdalin이 Prostaglandin E2 합성과 NO생성에 미치는 영향)

  • Jung, Hyung-Jin;Kim, Youn-Sub;Kim, Gyung-Jun
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.32 no.3
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    • pp.13-22
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    • 2019
  • Objectives : Armeniacae semen is the seed of Prunus armenica L. var. ansu MAXIM, and this is classified into Rosaceae. Armeniacae semen has been used for centuries in traditional oriental medicine for the treatment of pain and inflammatory diseases. Amygdalin is the major compound of Armeniacae semen, and it is now being used for the treatment of pain and cancer. Methods : In the present study, we compared the effects of an aqueous extract of Armeniacae semen and a solution of amygdalin extracted from Armeniacae semen on lipopolysaccharide(LPS)-stimulated prostaglandin E2 synthesis and nitric oxide production in mouse BV-2 microglial cells. For this study, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay, reverse transcription-polymerase chain reaction(RT-PCR), prostaglandin E2 immunoassay and nitric oxide detection were performed on mouse BV-2 microglial cells. Results : In the present study, an aqueous extract of Armeniacae semen and an amygdalin solution extracted from Armeniacae semen suppressed prostaglandin E2 synthesis and nitric oxide production by inhibiting the LPS-induced enhancement of cyclooxygenase-2(COX-2) mRNA and the inducible nitric oxide synthase mRNA in mouse BV-2 cells. For the cyclooxygenase-1(COX-1) expression, an aqueous extract of Armeniacae semen showed a more potent suppression effect compared to the amygdalin solution. However, the amygdalin solution more potently suppressed the LPS-induced COX-2 mRNA expression compared to the aqueous extract of Armeniacae semen. Conclusions : As a result, aqueous extract of Armeniacae semen and amygdalin exert anti-inflammatory and analgesic effects.

Experimental Study of Acupuncture at Haenggan(LR2) on the Cerebral Hemodynamics in Normal Rats (행간(行間) 자침(刺鍼)이 뇌혈류역학(腦血流力學) 작용(作用) 기전(機轉)에 미치는 실험적(實驗的) 연구(硏究))

  • Lee Yoon-Yeong;Na Chang-Su;Ryu Chung-Ryul;Cho Myeng-Rae;Shin Jeong-Chul
    • Korean Journal of Acupuncture
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    • v.20 no.4
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    • pp.31-40
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    • 2003
  • Objectives : The purpose of this study is to investigate whether Haenggan(LR2) Reduction in Acupuncture affects cerebral hemodynamics〔regional cerebral blood flow(rCBF), mean arterial blood pressure(MABP)〕in normal rats, and to make manifest whether Haenggan(LR2) Reduction in Acupuncture is mediated by cyclooxygenase or guanylate cyclase. Methods : This experiments was to investigate at the other changes of rCBF and MABP at Haenggan(LR2) Reduction in Acupuncture in normal rats, pretreated rats with indomethacin(1 mg/kg, i.v.) and pretreated rats with methylene blue$(10\;{\,u}g/kg,\;i.v.)$. Results : 1. Haenggan(LR2) Reduction in Acupuncture was significantly increased rCBF during acupuncture and after withdrawing of the needle. 2. Haenggan(LR2) Reduction in Acupuncture was decreased MABP during acupuncture, but Haenggan(LR2) Reduction in Acupuncture was increased MABP in compared with normal condition. 3. Pretreatment with indomethacin(1 mg/kg, i.v.) was significantly inhibited Haenggan(LR2) Reduction in Acupuncture induced increase of rCBF, but was increased Haenggan(LR2) Reduction in Acupuncture induced increase of MABP. 4. Pretreatment with methylene blue$(10\;{\mu}g/kg,\;i.v.)$ was significantly decreased Haenggan(LR2) Reduction in Acupuncture induced increase of rCBF and MABP. This results suggest that Haenggan(LR2) Reduction in Acupuncture increased rCBF by dilating pial arterial diameter, and the mechanism of Haenggan(LR2) Reduction in Acupuncture is mediated by guanylate cyclase.

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Inhibitory Action of Ulmus Davidiana Planch Extract Solution to Osteoclast Cell Proliferation and Prostaglandin E2 Synthesis in Mice

  • Park, Sang-Dong;Kim, Kap-Sung;Cho, Hyun-Seok;Lee, Seung-Deok;Kim, Kyung-Ho
    • Journal of Acupuncture Research
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    • v.23 no.2
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    • pp.91-102
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    • 2006
  • Objectives : Ulmus davidiana Planch (UD) has long been known to have anti-inflammatory and protective effects on damaged tissue, inflammation and bone among other functions. Methods : This study was undertaken to address whether the water extract of the bark of UD could modulate proliferation of mouse osteoclasts in vitro and to investigate its effect on cyclooxygenase-2 (COX-2), which converts arachidonic acid to prostaglandin E2 (PGE2) and is highly expressed in osteoclasts. Mouse osteoclasts were tested in vitro for growth inhibition, proliferation cell nuclear antigen expression, and COX-2 activity and expression after treatment with UD extract. Results : Its effects were compared with those of indomethacin (a nonselective COX inhibitor) and celecoxib (a selective COX-2 inhibitor) by Cell viability assay, Cell cycle analysis, Immunohistochemical analysis of PCNA expression, Western blot analysis and PGE2 Enzyme immunoassay (EIA). UD demonstrated a strong growth inhibitory action in both tested osteoclasts cells. The IC50s were $10\;{\mu}g/ml$ for UD, $6\;{\mu}M$ for celecoxib and $42\;{\mu}M$ for indomethacin. UD, as well as celecoxib and indomethacin, suppressed proliferation cell nuclear antigen expression and PGE2 synthesis in osteoclasts. UD inhibited COX-2 expression, whereas celecoxib inhibited COX-2 activity directly. Conclusion : UD selectively and effectively inhibits osteoclasts cell growth in vitro. Inhibitory action of PGE2 synthesis via suppression of COX-2 expression may be responsible for its anti-inflammatory activity.

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