MiR-26b Mimic Inhibits Glioma Proliferation In Vitro and In Vivo Suppressing COX-2 Expression.

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Chen, Zheng-Gang; Zheng, Chuan-Yi; Cai, Wang-Qing; Li, Da-Wei; Ye, Fu-Yue; Zhou, Jian; Wu, Ran; Yang, Kun

2017-08-11

Glioma is the most common malignant tumor of the nervous system. Studies have shown the microRNA (miR)-26b/cyclooxygenase (COX)-2 axis in the development and progression in many tumor cells. Our study aims to investigate the effect and mechanism of miR-26b/COX-2 axis in glioma. Decreased expression of miR-26b with increased level of COX-2 was found in glioma tissues compared with matched normal tissues. A strong negative correlation was observed between the level of miR-26b and COX-2 in 30 glioma tissues. The miR-26b was then overexpressed by transfecting miR-26b mimic into U-373 cells. The invasive cell number and wounld closing rate were reduced in U-373 cells transfected with miR-26b mimic. Besides, COX2 siRNA enhanced the effect of miR-26b mimic in suppressing the expression of p-ERK1 and p-JNK. Finally, the in vivo experiment revealed that miR-26b mimic transfection strongly reduced the tumor growth, tumor volume and the expression of matrix metalloproteinase (MMP)-2, MMP-9). Taken together, our research indicated a miR-26b/COX-2/ERK/JNK axis in regulating the motility of glioma in vitro and in vivo, providing a new sight for treatment of glioma.

Aggravation of Alzheimer's disease due to the COX-2-mediated reciprocal regulation of IL-1β and Aβ between glial and neuron cells.

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Wang, Pu; Guan, Pei-Pei; Wang, Tao; Yu, Xin; Guo, Jian-Jun; Wang, Zhan-You

2014-08-01

Alzheimer's disease (AD) is the most common form of dementia and displays the characteristics of chronic neurodegenerative disorders; amyloid plaques (AP) that contain amyloid β-protein (Aβ) accumulate in AD, which is also characterized by tau phosphorylation. Epidemiological evidence has demonstrated that long-term treatment with nonsteroidal anti-inflammatory drugs (NSAIDs) markedly reduces the risk of AD by inhibiting the expression of cyclooxygenase 2 (COX-2). Although the levels of COX-2 and its metabolic product prostaglandin (PG)E2 are elevated in the brain of AD patients, the mechanisms for the development of AD remain unknown. Using human- or mouse-derived glioblastoma and neuroblastoma cell lines as model systems, we delineated the signaling pathways by which COX-2 mediates the reciprocal regulation of interleukin-1β (IL-1β) and Aβ between glial and neuron cells. In glioblastoma cells, COX-2 regulates the synthesis of IL-1β in a PGE2 -dependent manner. Moreover, COX-2-derived PGE2 signals the activation of the PI3-K/AKT and PKA/CREB pathways via cyclic AMP; these pathways transactivate the NF-κB p65 subunit via phosphorylation at Ser 536 and Ser 276, leading to IL-1β synthesis. The secretion of IL-1β from glioblastoma cells in turn stimulates the expression of COX-2 in human or mouse neuroblastoma cells. Similar regulatory mechanisms were found for the COX-2 regulation of BACE-1 expression in neuroblastoma cells. More importantly, Aβ deposition mediated the inflammatory response of glial cells via inducing the expression of COX-2 in glioblastoma cells. These findings not only provide new insights into the mechanisms of COX-2-induced AD but also initially define the therapeutic targets of AD. © 2014 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

Regulation of COX and LOX by curcumin.

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Rao, Chinthalapally V

2007-01-01

Turmeric (Curcuma longa) is extensively used as a household remedy for various diseases. For the last few decades, work has been done to establish the biological activities and pharmacological actions of curcumin, the principle constituent of turmeric. Curcumin has proven to be beneficial in the prevention and treatment of a number of inflammatory diseases due to its anti-inflammatory activity. Arachidonic acid-derived lipid mediators that are intimately involved in inflammation are biosynthesized by pathways dependent on cyclooxygenase (COX) and lipoxygenase (LOX) enzymes. The role of LOX and COX isoforms, particularly COX-2, in the inflammation has been well established. At cellular and molecular levels, curcumin has been shown to regulate a number of signaling pathways, including the eicosanoid pathway involving COX and LOX. A number of studies have been conducted that support curcumin-mediated regulation of COX and LOX pathways, which is an important mechanism by which curcumin prevents a number of disease processes, including the cancer. The specific regulation of 5-LOX and COX-2 by curcumin is not fully established; however, existing evidence indicates that curcumin regulates LOX and COX-2 predominately at the transcriptional level and, to a certain extent, the posttranslational level. Thus, the curcumin-selective transcriptional regulatory action of COX-2, and dual COX/LOX inhibitory potential of this naturally occurring agent provides distinctive advantages over synthetic COX/LOX inhibitors, such as nonsteroidal anti-inflammatory drugs. In this review, we discuss evidence that supports the regulation of COX and LOX enzymes by curcumin as the key mechanism for its beneficial effects in preventing various inflammatory diseases.

Detection of EGFR and COX-2 Expression by Immunohistochemical Method on a Tissue Microarray Section in Lung Cancer and Biological Significance

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Xinyun WANG

2010-02-01

Full Text Available Background and objective Epidermal growth factor receptor (EGFR and cyclooxygenase-2 (COX-2, which can regulate growth, invasion and metastasis of tumor through relevant signaling pathway, have been detected in a variety of solid tumors. The aim of this study is to investigate the biological significance of EGFR and COX-2 expression in lung cancer and the relationship between them. Methods The expression of EGFR and COX-2 was detected in 89 primary lung cancer tissues, 12 premaliganant lesions, 12 lymph node metastases, and 10 normal lung tissues as the control by immunohistochemical method on a tissue microarray section. Results EGFR protein was detectable in 59.6%, 41.7%, and 66.7% of primary lung cancer tissues, premalignant lesions and lymph node metastases, respectively; COX-2 protein was detectable in 52.8%, 41.7%, and 66.7% of primary lung cancer tissues, premalignant lesions and lymph node metastases, respectively, which were significantly higher than those of the control (P 0.05. COX-2 expression was related to gross type (P < 0.05. A highly positive correlation was observed between EGFR and COX-2 expression (P < 0.01. Conclusion Overexpression of EGFR and COX-2 may play an important role in the tumorgenesis, progression and malignancy of lung cancer. Detection of EGFR and COX-2 expression might be helpful to diagnosis and prognosis of lung cancer.

Radiolabeled COX-2 Inhibitors for Non-Invasive Visualization of COX-2 Expression and Activity — A Critical Update

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Torsten Kniess

2013-05-01

Full Text Available Cyclooxygenase-2 (COX-2 is a key player in inflammation. Its overexpression is directly associated with various inflammatory diseases and, additionally, with several processes of carcinogenesis. The development of new selective COX-2 inhibitors (COXIBs for use in cancer treatment is in the focus of the medicinal chemistry research field. For this purpose, a set of methods is available to determine COX-2 expression and activity in vitro and ex vivo but it is still a problem to functionally characterize COX-2 in vivo. This review focusses on imaging agents targeting COX-2 which have been developed for positron emission tomography (PET and single photon emission computed tomography (SPECT since 2005. The literature reveals that different radiochemical methods are available to synthesize COXIBs radiolabeled with fluorine-18, carbon-11, and isotopes of radioiodine. Unfortunately, most of the compounds tested did not show sufficient stability in vivo due to de[18F]fluorination or de[11C]methylation or they failed to bind specifically in the target region. So, suitable stability in vivo, matching lipophilicity for the target compartment and both high affinity and selectivity for COX-2 were identified as prominent criteria for radiotracer development. Up to now, it is not clear what approach and which model is the most suited to evaluate COX-2 targeting imaging agents in vivo. However, for proof of principle it has been shown that some radiolabeled compounds can bind specifically in COX-2 overexpressing tissue which gives hope for future work in this field.

CD36 deficiency leads to choroidal involution via COX2 down-regulation in rodents.

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Marianne Houssier

2008-02-01

Full Text Available BACKGROUND: In the Western world, a major cause of blindness is age-related macular degeneration (AMD. Recent research in angiogenesis has furthered the understanding of choroidal neovascularization, which occurs in the "wet" form of AMD. In contrast, very little is known about the mechanisms of the predominant, "dry" form of AMD, which is characterized by retinal atrophy and choroidal involution. The aim of this study is to elucidate the possible implication of the scavenger receptor CD36 in retinal degeneration and choroidal involution, the cardinal features of the dry form of AMD. METHODS AND FINDINGS: We here show that deficiency of CD36, which participates in outer segment (OS phagocytosis by the retinal pigment epithelium (RPE in vitro, leads to significant progressive age-related photoreceptor degeneration evaluated histologically at different ages in two rodent models of CD36 invalidation in vivo (Spontaneous hypertensive rats (SHR and CD36-/- mice. Furthermore, these animals developed significant age related choroidal involution reflected in a 100%-300% increase in the avascular area of the choriocapillaries measured on vascular corrosion casts of aged animals. We also show that proangiogenic COX2 expression in RPE is stimulated by CD36 activating antibody and that CD36-deficient RPE cells from SHR rats fail to induce COX2 and subsequent vascular endothelial growth factor (VEGF expression upon OS or antibody stimulation in vitro. CD36-/- mice express reduced levels of COX2 and VEGF in vivo, and COX2-/- mice develop progressive choroidal degeneration similar to what is seen in CD36 deficiency. CONCLUSIONS: CD36 deficiency leads to choroidal involution via COX2 down-regulation in the RPE. These results show a novel molecular mechanism of choroidal degeneration, a key feature of dry AMD. These findings unveil a pathogenic process, to our knowledge previously undescribed, with important implications for the development of new therapies.

A Cross-Talk Between NFAT and NF-κB Pathways is Crucial for Nickel-Induced COX-2 Expression in Beas-2B Cells

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Cai, T.; Li, X.; Ding, J.; Luo, W.; Li, J.; Huang, C.

2013-01-01

Cyclooxygenase-2 (COX-2) is a critical enzyme implicated in chronic inflammation-associated cancer development. Our studies have shown that the exposure of Beas-2B cells, a human bronchial epithelial cell line, to lung carcinogenic nickel compounds results in increased COX-2 expression. However, the signaling pathways leading to nickel-induced COX-2 expression are not well understood. In the current study, we found that the exposure of Beas-2B cells to nickel compounds resulted in the activation of both nuclear factor of activated T cell (NFAT) and nuclear factor-κB (NF-κB). The expression of COX-2 induced upon nickel exposure was inhibited by either a NFAT pharmacological inhibitor or the knockdown of NFAT3 by specific siRNA. We further found that the activation of NFAT and NF-κB was dependent on each other. Since our previous studies have shown that NF-κB activation is critical for nickel-induced COX-2 expression in Beas-2B cells exposed to nickel compounds under same experimental condition, we anticipate that there might be a cross-talk between the activation of NFAT and NF-κB for the COX-2 induction due to nickel exposure in Beas-2B cells. Furthermore, we showed that the scavenging of reactive oxygen species (ROS) by introduction of mitochondrial catalase inhibited the activation of both NFAT and NF-κB, and the induction of COX-2 due to nickel exposure. Taken together, our results defining the evidence showing a key role of the cross-talk between NFAT and NF-κB pathways in regulating nickel-induced COX-2 expression, further provide insight into the understanding of the molecular mechanisms linking nickel exposure to its lung carcinogenic effects. PMID:21486220

2-Chlorohexadecanal and 2-chlorohexadecanoic acid induce COX-2 expression in human coronary artery endothelial cells

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Messner, Maria C.; Albert, Carolyn J.; Ford, David A.

2008-01-01

2-Chlorohexadecanal (2-ClHDA), a 16-carbon chain chlorinated fatty aldehyde that is produced by reactive chlorinating species attack of plasmalogens, is elevated in atherosclerotic plaques, infarcted myocardium, and activated leukocytes. We tested the hypothesis that 2-ClHDA and its metabolites, 2-chlorohexadecanoic acid (2-ClHA) and 2-chlorohexadecanol (2-ClHOH), induce COX-2 expression in human coronary artery endothelial cells (HCAEC). COX-2 protein expression increased in response to 2-Cl...

Immunohistochemical Expression of COX-2 in Uterine Serous Carcinoma Tissue

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Joseph Menczer

2016-03-01

Material and methods. Cox-2 expression assessment by immunohistochemistry was performed on deparaffinized sections of paraffin-embedded tissue blocks of consecutive available USC uterine specimens of patients diagnosed from 2000 to 2014. Staining of more than 10% of the cells was considered positive. Staining intensity was graded on a 0 and ndash;3 scale. A scoring index was calculated by multiplying the intensity grade by the percentage of stained cells and considered low when it was equal to 1 or less and high when it was more than 1. Clinicopathological data were retrospectively abstracted from the records of the study group patients Results. The study comprised uterine specimens of 31 USC patients. Positive immunohistochemical staining was observed in 25 (80.6% USC specimens and a high score in 6 (19.4% of them. No association between immunohistochemical staining parameters and clinicopathological prognostic factors was observed. Conclusion. Although our findings should be verified in larger series, it seems that in view of the lack of association between immunohistochemical Cox-2 staining parameters in USC tissue and clinicopathological prognostic factors, this aggressive tumor is not a candidate for the use of selective Cox-2 inhibitors. Key words: Cox-2 expression, uterine carcinosarcoma, clinicopathological prognostic factors [J Interdiscipl Histopathol 2016; 4(1.000: 9-12

Expression of Beta-catenin, COX-2 and iNOS in Colorectal Cancer: Relevance of COX-2 and iNOS Inhibitors for Treatment in Malaysia

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Seok Kwan Hong

2004-01-01

Conclusions: The accumulation of β-catenin does not seem to be sufficient to activate pathways that lead to increased COX-2 and iNOS expression. A high proportion of colorectal cancers were found to express COX-2 and a significant number produced iNOS, suggesting that their inhibitors may be potentially useful as chemotherapeutic agents in the management of colorectal cancer.

Prostaglandin E2-Induced COX-2 Expressions via EP2 and EP4 Signaling Pathways in Human LoVo Colon Cancer Cells

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Hsi-Hsien Hsu

2017-05-01

Full Text Available Metastasis is the most dangerous risk faced by patients with hereditary non-polyposis colon cancer (HNPCC. The expression of matrix metalloproteinases (MMPs has been observed in several types of human cancers and regulates the efficacy of many therapies. Here, we show that treatment with various concentrations of prostaglandin E2 (PGE2; 0, 1, 5 or 10 μM promotes the migration ability of the human LoVo colon cancer cell line. As demonstrated by mRNA and protein expression analyses, EP2 and EP4 are the major PGE2 receptors expressed on the LoVo cell membrane. The Phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K/Akt cell survival pathway was upregulated by EP2 and EP4 activation. Following the activation of the PI3K/Akt pathway, β-catenin translocated into the nucleus and triggered COX2 transcription via LEF-1 and TCF-4 and its subsequent translation. COX2 expression correlated with the elevation in the migration ability of LoVo cells. The experimental evidence shows a possible mechanism by which PGE2 induces cancer cell migration and further suggests PGE2 to be a potential therapeutic target in colon cancer metastasis. On inhibition of PGE2, in order to determine the downstream pathway, the levels of PI3K/Akt pathway were suppressed and the β-catenin expression was also modulated. Inhibition of EP2 and EP4 shows that PGE2 induces protein expression of COX-2 through EP2 and EP4 receptors in LoVo colon cancer cells.

Autocrine prostaglandin E2 signaling promotes promonocytic leukemia cell survival via COX-2 expression and MAPK pathway

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Lee, Jaetae; Lee, Young Sup

2015-01-01

The COX-2/PGE2 pathway has been implicated in the occurrence and progression of cancer. The underlying mechanisms facilitating the production of COX-2 and its mediator, PGE2, in cancer survival remain unknown. Herein, we investigated PGE2-induced COX-2 expression and signaling in HL-60 cells following menadione treatment. Treatment with PGE2 activated anti-apoptotic proteins such as Bcl-2 and Bcl-xL while reducing pro-apoptotic proteins, thereby enhancing cell survival. PGE2 not only induced COX-2 expression, but also prevented casapse-3, PARP, and lamin B cleavage. Silencing and inhibition of COX-2 with siRNA transfection or treatment with indomethacin led to a pronounced reduction of the extracellular levels of PGE2, and restored the menadione-induced cell death. In addition, pretreatment of cells with the MEK inhibitor PD98059 and the PKA inhibitor H89 abrogated the PGE2-induced expression of COX-2, suggesting involvement of the MAPK and PKA pathways. These results demonstrate that PGE2 signaling acts in an autocrine manner, and specific inhibition of PGE2 will provide a novel approach for the treatment of leukemia. [BMB Reports 2015; 48(2): 109-114] PMID:24965577

Eupafolin inhibits PGE2 production and COX2 expression in LPS-stimulated human dermal fibroblasts by blocking JNK/AP-1 and Nox2/p47phox pathway

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Tsai, Ming-Horng; Lin, Zih-Chan; Liang, Chan-Jung; Yen, Feng-Lin; Chiang, Yao-Chang; Lee, Chiang-Wen

2014-01-01

Eupafolin, a major active component found in the methanol extracts of Phyla nodiflora, has been used to treat inflammation of skin. We examined its effects on cyclooxygenase-2 (COX-2) expression in LPS-treated human dermal fibroblasts. Lipopolysaccharide (LPS) significantly increased prostaglandin-E2 (PGE2) production associated with increased COX-2 expression in Hs68 cells. This effect was blocked by eupafolin, TLR-4 antibody, antioxidants (APO and NAC), as well as inhibitors, including U0126 (ERK1/2), SB202190 (p38), SP600125 (JNK1/2), and Tanshinone IIA (AP-1). In gene regulation level, qPCR and promoter assays revealed that COX-2 expression was attenuated by eupafolin. In addition, eupafolin also ameliorated LPS-induced p47 phox activation and decreased reactive oxygen species (ROS) generation and NADPH oxidase (Nox) activity. Moreover, pretreatment with eupafolin and APO led to reduced LPS-induced phosphorylation of ERK1/2, JNK, and p38. Further, eupafolin attenuated LPS-induced increase in AP-1 transcription factor binding activity as well as the increase in the phosphorylation of c-Jun and c-Fos. In vivo studies have shown that in dermal fibroblasts of LPS treated mice, eupafolin exerted anti-inflammation effects by decreasing COX-2 protein levels. Our results reveal a novel mechanism for anti-inflammatory and anti-oxidative effects of eupafolin that involved inhibition of LPS-induced ROS generation, suppression of MAPK phosphorylation, diminished DNA binding activity of AP-1 and attenuated COX-2 expression leading to reduced production of prostaglandin E2 (PGE2). Our results demonstrate that eupafolin may be used to treat inflammatory responses associated with dermatologic diseases. - Highlights: • LPS activates the Nox2/p47 phox /JNK/AP-1 and induces COX2 expression in Hs68 cells. • Eupafolin inhibits LPS-induced COX-2 expression via Nox2/p47 phox inhibition. • Eupafolin may be used in the treatment of skin diseases involving inflammation

[Small interfering RNA-mediated COX-2 gene silencing enhances chemosensitivity of KB/VCR cells by suppressing MDR-1 gene expression and P-glycoprotein activity].

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Mo, Xianchao; Li, Weizhong

2014-05-01

To investigate the effect of small interfering RNA (siRNA)-mediated COX-2 gene silencing in enhancing the chemosensitivity of KB/VCR cell lines. KB/VCR cells were trasnfected with COX-2 siRNA were examined for expressions of COX-2 and MDR-1 mRNAs with RT-PCR and for Rho-123 accumulation using flow cytometry. MTT assay was used to analyze the proliferation of the transfected KB/VCR cells. Compared with the negative and blank control groups, COX-2 siRNA transfection resulted in significant growth inhibition of KB/VCR cells exposed to vincristine (PKB/VCR cells. COX-2 gene silencing can enhance the chemosensitivity of KB/VCR cells to vincristine, the mechanism of which may involve down-regulated MDR-1 gene expression and inhibition of P-glycoprotein activity.

Eupafolin inhibits PGE2 production and COX2 expression in LPS-stimulated human dermal fibroblasts by blocking JNK/AP-1 and Nox2/p47{sup phox} pathway

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Tsai, Ming-Horng [Department of Pediatrics, Division of Neonatology and Pediatric Hematology/Oncology, Chang Gung Memorial Hospital, Yunlin, Taiwan (China); Lin, Zih-Chan [Department of Fragrance and Cosmetic Science, College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan (China); Liang, Chan-Jung [Department of Anatomy and Cell Biology, College of Medicine, National Taiwan University, Taipei, Taiwan (China); Yen, Feng-Lin [Department of Fragrance and Cosmetic Science, College of Pharmacy, Kaohsiung Medical University, Kaohsiung, Taiwan (China); Institute of Biomedical Sciences, Sun Yat-Sen University, 70 Lienhai Rd., Kaohsiung, Taiwan (China); Chiang, Yao-Chang [Center for Drug Abuse and Addiction, China Medical University Hospital, Taichung, Taiwan (China); China Medical University, Taichung, Taiwan (China); Lee, Chiang-Wen, E-mail: cwlee@gw.cgust.edu.tw [Department of Nursing, Division of Basic Medical Sciences, Chang Gung University of Science and Technology, Chia-Yi, Taiwan (China); Chronic Diseases and Health Promotion Research Center, Chang Gung University of Science and Technology, Chia-Yi, Taiwan (China); Research Center for Industry of Human Ecology, Chang Gung University of Science and Technology, Taoyuan, Taiwan (China)

2014-09-01

Eupafolin, a major active component found in the methanol extracts of Phyla nodiflora, has been used to treat inflammation of skin. We examined its effects on cyclooxygenase-2 (COX-2) expression in LPS-treated human dermal fibroblasts. Lipopolysaccharide (LPS) significantly increased prostaglandin-E2 (PGE2) production associated with increased COX-2 expression in Hs68 cells. This effect was blocked by eupafolin, TLR-4 antibody, antioxidants (APO and NAC), as well as inhibitors, including U0126 (ERK1/2), SB202190 (p38), SP600125 (JNK1/2), and Tanshinone IIA (AP-1). In gene regulation level, qPCR and promoter assays revealed that COX-2 expression was attenuated by eupafolin. In addition, eupafolin also ameliorated LPS-induced p47 phox activation and decreased reactive oxygen species (ROS) generation and NADPH oxidase (Nox) activity. Moreover, pretreatment with eupafolin and APO led to reduced LPS-induced phosphorylation of ERK1/2, JNK, and p38. Further, eupafolin attenuated LPS-induced increase in AP-1 transcription factor binding activity as well as the increase in the phosphorylation of c-Jun and c-Fos. In vivo studies have shown that in dermal fibroblasts of LPS treated mice, eupafolin exerted anti-inflammation effects by decreasing COX-2 protein levels. Our results reveal a novel mechanism for anti-inflammatory and anti-oxidative effects of eupafolin that involved inhibition of LPS-induced ROS generation, suppression of MAPK phosphorylation, diminished DNA binding activity of AP-1 and attenuated COX-2 expression leading to reduced production of prostaglandin E2 (PGE2). Our results demonstrate that eupafolin may be used to treat inflammatory responses associated with dermatologic diseases. - Highlights: • LPS activates the Nox2/p47{sup phox}/JNK/AP-1 and induces COX2 expression in Hs68 cells. • Eupafolin inhibits LPS-induced COX-2 expression via Nox2/p47{sup phox} inhibition. • Eupafolin may be used in the treatment of skin diseases involving inflammation.

Minimizing the cancer-promotional activity of cox-2 as a central strategy in cancer prevention.

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McCarty, Mark F

2012-01-01

A recent meta-analysis examining long-term mortality in subjects who participated in controlled studies evaluating the impact of daily aspirin on vascular risk, has concluded that aspirin confers substantial protection from cancer mortality. Remarkably, low-dose aspirin was as effective as higher-dose regimens; hence this protection may be achievable with minimal risk. There is reason to believe that this protection stems primarily from inhibition of cox-2 in pre-neoplastic lesions. Since safe aspirin regimens can only achieve a partial and transitory inhibition of cox-2, it may be feasible to complement the cancer-protective benefit of aspirin with other measures which decrease cox-2 expression or which limit the bioactivity of cox-2-derived PGE2. Oxidative stress boosts cox-2 expression by up-regulating activation of NF-kappaB and MAP kinases; NADPH oxidase activation may thus promote carcinogenesis by increasing cox-2 expression while also amplifying oxidant-mediated mutagenesis. A prospective cohort study has observed that relatively elevated serum bilirubin levels are associated with a marked reduction in subsequent cancer mortality; this may reflect bilirubin's physiological role as a potent inhibitor of NADPH oxidase. It may be feasible to mimic this protective effect by supplementing with spirulina, a rich source of a phycobilin which shares bilirubin's ability to inhibit NADPH oxidase. Ancillary antioxidant measures - phase 2 inducing phytochemicals, melatonin, N-acetylcysteine, and astaxanthin - may also aid cox-2 down-regulation. The cancer protection often associated with high-normal vitamin D status may be attributable, in part, to the ability of the activated vitamin D receptor to decrease cox-2 expression while promoting PGE2 catabolism and suppressing the expression of PGE2 receptors. Diets with a relatively low ratio of omega-6 to long-chain omega-3 fats may achieve cancer protection by antagonizing the production and bioactivity of PGE2. Growth

ST6Gal1, Cox-2 and HB-EGF mRNA Expression in Breast Cancer

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Aliakbar Taherian

2015-01-01

Full Text Available Background: ST6Gal1, Cox-2 and HB-EGF genes are involved in different tumors and their enhanced expressions often correlate with poor prognosis. In this study we assay the expressions of these genes by reverse transcriptase-PCR in 54 breast cancer samples. Methods: Tissue samples were either formalin-fixed for histopathological examination or frozen for reverse transcriptase-PCR. Image program was used for the densitometry of the image of the gels and the expression of different genes was normalized with beta actin expression. The student's t-test and correlation matrix were used for data analyses. Results: We observed significantly higher expressions of ST6Gal1 (P= 0.040, Cox- 2 (P= 0.001 and HB-EGF (P= 0.009 in the tumor region compared to the margin samples. A significant correlation was found between HB-EGF and Cox-2 expression (P= 0.001. There was a positive correlation between total score, tumor size, histology grade and nuclear grade but there was a reverse correlation between age and tumor size, histology grade and total score. Conclusion: Expressions of ST6Gal1, Cox-2 and HB-EGF in breast tumor samples in this and a number of other studies emphasize their role as important markers in breast cancer. The use of medications to inhibit either their individual expressions or the possible inhibition of all three genes may improve patient survival and prevent metastasis.

Sphingosine 1-phosphate (S1P) induces COX-2 expression and PGE2 formation via S1P receptor 2 in renal mesangial cells.

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Völzke, Anja; Koch, Alexander; Meyer Zu Heringdorf, Dagmar; Huwiler, Andrea; Pfeilschifter, Josef

2014-01-01

Understanding the mechanisms of sphingosine 1-phosphate (S1P)-induced cyclooxygenase (COX)-2 expression and prostaglandin E2 (PGE2) formation in renal mesangial cells may provide potential therapeutic targets to treat inflammatory glomerular diseases. Thus, we evaluated the S1P-dependent signaling mechanisms which are responsible for enhanced COX-2 expression and PGE2 formation in rat mesangial cells under basal conditions. Furthermore, we investigated whether these mechanisms are operative in the presence of angiotensin II (Ang II) and of the pro-inflammatory cytokine interleukin-1β (IL-1β). Treatment of rat and human mesangial cells with S1P led to concentration-dependent enhanced expression of COX-2. Pharmacological and molecular biology approaches revealed that the S1P-dependent increase of COX-2 mRNA and protein expression was mediated via activation of S1P receptor 2 (S1P2). Further, inhibition of Gi and p42/p44 MAPK signaling, both downstream of S1P2, abolished the S1P-induced COX-2 expression. In addition, S1P/S1P2-dependent upregulation of COX-2 led to significantly elevated PGE2 levels, which were further potentiated in the presence of Ang II and IL-1β. A functional consequence downstream of S1P/S1P2 signaling is mesangial cell migration that is stimulated by S1P. Interestingly, inhibition of COX-2 by celecoxib and SC-236 completely abolished the migratory response. Overall, our results demonstrate that extracellular S1P induces COX-2 expression via activation of S1P2 and subsequent Gi and p42/p44 MAPK-dependent signaling in renal mesangial cells leading to enhanced PGE2 formation and cell migration that essentially requires COX-2. Thus, targeting S1P/S1P2 signaling pathways might be a novel strategy to treat renal inflammatory diseases. © 2013.

Ubiquitin-proteasomal degradation of COX-2 in TGF-β stimulated human endometrial cells is mediated through endoplasmic reticulum mannosidase I.

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Singh, Mohan; Chaudhry, Parvesh; Parent, Sophie; Asselin, Eric

2012-01-01

Cyclooxygenase (COX)-2 is a key regulatory enzyme in the production of prostaglandins (PG) during various physiological processes. Mechanisms of COX-2 regulation in human endometrial stromal cells (human endometrial stromal cells) are not fully understood. In this study, we investigate the role of TGF-β in the regulation of COX-2 in human uterine stromal cells. Each TGF-β isoform decreases COX-2 protein level in human uterine stromal cells in Smad2/3-dependent manner. The decrease in COX-2 is accompanied by a decrease in PG synthesis. Knockdown of Smad4 using specific small interfering RNA prevents the decrease in COX-2 protein, confirming that Smad pathway is implicated in the regulation of COX-2 expression in human endometrial stromal cells. Pretreatment with 26S proteasome inhibitor, MG132, significantly restores COX-2 protein and PG synthesis, indicating that COX-2 undergoes proteasomal degradation in the presence of TGF-β. In addition, each TGF-β isoform up-regulates endoplasmic reticulum (ER)-mannosidase I (ERManI) implying that COX-2 degradation is mediated through ER-associated degradation pathway in these cells. Furthermore, inhibition of ERManI activity using the mannosidase inhibitor (kifunensine), or small interfering RNA-mediated knockdown of ERManI, prevents TGF-β-induced COX-2 degradation. Taken together, these studies suggest that TGF-β promotes COX-2 degradation in a Smad-dependent manner by up-regulating the expression of ERManI and thereby enhancing ER-associated degradation and proteasomal degradation pathways.

EGF-R is Expressed and AP-1 and NF-κ:B Are Activated in Stromal Myofibroblasts Surrounding Colon Adenocarcinomas Paralleling Expression of COX-2 and VEGF

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Panagiotis A. Konstantinopoulos

2007-01-01

Full Text Available Background: COX-2 and VEGF are important triggers of colon cancer growth, metastasis and angiogenesis. Cox-2 promoter contains transcriptional regulatory elements for AP-1 and NF-κ:B transcription factors whilst vegf is a known AP-1 downstream target gene. We investigated whether stromal myofibroblasts surrounding colon adenocarcinomas express COX-2 and VEGF and whether activation of AP-1 and NF-κ:B, as well as expression of EGF-R parallel expression of COX-2 and VEGF in these cells. Methods: Immunohistochemical methodology was performed on archival sections from 40 patients with colon adenocarcinomas. We evaluated c-FOS, p-c-JUN (phosphorylated c-JUN, p-Iκ:B-α (phosphorylated Iκ:B-α, EGF-R, COX-2, NF-κ:B and VEGF expression in stromal myofibroblasts surrounding colon adenocarcinomas. Double immunostaining with a-smooth muscle actin and each antibody was done to verify the expression of these molecules in stromal myofibroblasts. Results: VEGF, p-Iκ:B-α, NF-κ:B, c-FOS, p-c-JUN, EGF-R and COX-2 were expressed in stromal myofibroblasts surrounding colon adenocarcinomas in the majority of cases. EGF-R, p-Iκ:B-α, NF-κ:B, c-FOS and p-c-JUN correlated positively with COX-2 and VEGF expression. Conclusion: Stromal myofibroblasts surrounding colon adenocarcinomas are an important source of VEGF and COX-2 production, while AP-1 and NF-κ:B transcription factors are activated and EGF-R is expressed in these cells and associated with COX-2 and VEGF production.

COX-2 and Prostaglandin EP3/EP4 Signaling Regulate the Tumor Stromal Proangiogenic Microenvironment via CXCL12-CXCR4 Chemokine Systems

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Katoh, Hiroshi; Hosono, Kanako; Ito, Yoshiya; Suzuki, Tatsunori; Ogawa, Yasufumi; Kubo, Hidefumi; Kamata, Hiroki; Mishima, Toshiaki; Tamaki, Hideaki; Sakagami, Hiroyuki; Sugimoto, Yukihiko; Narumiya, Shuh; Watanabe, Masahiko; Majima, Masataka

2010-01-01

Bone marrow (BM)–derived hematopoietic cells, which are major components of tumor stroma, determine the tumor microenvironment and regulate tumor phenotypes. Cyclooxygenase (COX)−2 and endogenous prostaglandins are important determinants for tumor growth and tumor-associated angiogenesis; however, their contributions to stromal formation and angiogenesis remain unclear. In this study, we observed that Lewis lung carcinoma cells implanted in wild-type mice formed a tumor mass with extensive stromal formation that was markedly suppressed by COX-2 inhibition, which reduced the recruitment of BM cells. Notably, COX-2 inhibition attenuated CXCL12/CXCR4 expression as well as expression of several other chemokines. Indeed, in a Matrigel model, prostaglandin (PG) E2 enhanced stromal formation and CXCL12/CXCR4 expression. In addition, a COX-2 inhibitor suppressed stromal formation and reduced expression of CXCL12/CXCR4 and a fibroblast marker (S100A4) in a micropore chamber model. Moreover, stromal formation after tumor implantation was suppressed in EP3−/− mice and EP4−/− mice, in which stromal expression of CXCL12/CXCR4 and S100A4 was reduced. The EP3 or EP4 knockout suppressed S100A4+ fibroblasts, CXCL12+, and/or CXCR4+ stromal cells as well. Immunofluorescent analyses revealed that CXCL12+CXCR4+S100A4+ fibroblasts mainly comprised stromal cells and most of these were recruited from the BM. Additionally, either EP3- or EP4-specific agonists stimulated CXCL12 expression by fibroblasts in vitro. The present results address the novel activities of COX-2/PGE2-EP3/EP4 signaling that modulate tumor biology and show that CXCL12/CXCR4 axis may play a crucial role in tumor stromal formation and angiogenesis under the control of prostaglandins. PMID:20110411

Effects of the estrous cycle, pregnancy and interferon tau on expression of cyclooxygenase two (COX-2 in ovine endometrium

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Bazer Fuller W

2003-08-01

Full Text Available Abstract In sheep, the uterus produces luteolytic pulses of prostaglandin F2α (PGF on Days 15 to 16 of estrous cycle to regress the corpus luteum (CL. These PGF pulses are produced by the endometrial lumenal epithelium (LE and superficial ductal glandular epithelium (sGE in response to binding of pituitary and/or luteal oxytocin to oxytocin receptors (OTR and liberation of arachidonic acid, the precursor of PGF. Cyclooxygenase-one (COX-1 and COX-2 are rate-limiting enzymes in PGF synthesis, and COX-2 is the major form expressed in ovine endometrium. During pregnancy recognition, interferon tau (IFNτ, produced by the conceptus trophectoderm, acts in a paracrine manner to suppress development of the endometrial epithelial luteolytic mechanism by inhibiting transcription of estrogen receptor α (ERα (directly and OTR (indirectly genes. Conflicting studies indicate that IFNτ increases, decreases or has no effect on COX-2 expression in bovine and ovine endometrial cells. In Study One, COX-2 mRNA and protein were detected solely in endometrial LE and sGE of both cyclic and pregnant ewes. During the estrous cycle, COX-2 expression increased from Days 10 to 12 and then decreased to Day 16. During early pregnancy, COX-2 expression increased from Days 10 to 12 and remained higher than in cyclic ewes. In Study Two, intrauterine infusion of recombinant ovine IFNτ in cyclic ewes from Days 11 to 16 post-estrus did not affect COX-2 expression in the endometrial epithelium. These results clearly indicate that IFNτ has no effect on expression of the COX-2 gene in the ovine endometrium. Therefore, antiluteolytic effects of IFNτ are to inhibit ERα and OTR gene transcription, thereby preventing endometrial production of luteolytic pulses of PGF. Indeed, expression of COX-2 in the endometrial epithelia as well as conceptus is likely to have a beneficial regulatory role in implantation and development of the conceptus.

γ-Oryzanol suppresses COX-2 expression by inhibiting reactive oxygen species-mediated Erk1/2 and Egr-1 signaling in LPS-stimulated RAW264.7 macrophages.

Science.gov (United States)

Shin, Soon Young; Kim, Heon-Woong; Jang, Hwan-Hee; Hwang, Yu-Jin; Choe, Jeong-Sook; Kim, Jung-Bong; Lim, Yoongho; Lee, Young Han

2017-09-16

Cyclooxygenase (COX)-2 produces prostanoids, which contribute to inflammatory responses. Nuclear factor (NF)-κB is a key transcription factor mediating COX-2 expression. γ-Oryzanol is an active component in rice bran oil, which inhibits lipopolysaccharide (LPS)-mediated COX-2 expression by inhibiting NF-κB. However, the inhibition of COX-2 expression by γ-oryzanol independently of NF-κB is poorly understood. We found that LPS upregulated Egr-1 expression at the transcriptional level. Forced expression of Egr-1 trans-activated the Cox-2 promoter independently of NF-κB. In contrast, silencing of Egr-1 abrogated LPS-mediated COX-2 expression. LPS produced reactive oxygen species (ROS), which, in turn, induced Egr-1 expression via the Erk1/2 MAPK pathway. ROS scavenging activity of γ-oryzanol suppressed Egr-1 expression by inhibiting the Erk1/2 MAPK pathway. Our results suggest that γ-oryzanol inhibits LPS-mediated COX-2 expression by suppressing Erk1/2-mediated Egr-1 expression. This study supports that γ-oryzanol may be useful for ameliorating LPS-mediated inflammatory responses. Copyright © 2017 Elsevier Inc. All rights reserved.

Correlation analysis between expression of PCNA, Ki-67 and COX-2 and X-ray features in mammography in breast cancer.

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Qiu, Xiaoming; Mei, Jixin; Yin, Jianjun; Wang, Hong; Wang, Jinqi; Xie, Ming

2017-09-01

This study investigated expression of proliferating cell nuclear antigen (PCNA), proliferation-associated nuclear antigen (Ki-67) and cyclooxygenase-2 (COX-2) in tissues of breast invasive ductal carcinoma, and analyzed the correlations between these indexes and X-ray features in mammography. A total of 90 patients who were admitted to Huangshi Central Hospital and diagnosed as breast invasive ductal carcinoma from January 2014 to January 2016 were selected. The expression of PCNA, Ki-67 and COX-2 in cancer tissues and cancer-adjacent normal tissues of patients were detected by immunohistochemical staining, and X-ray features in mammography of patients were observed. By using Spearman correlation analysis, the correlations between expression of PCNA, Ki-67 and COX-2 and X-ray features in mammography in breast cancer were investigated. As a result, the positive expression rates of PCNA, Ki-67 and COX-2 in cancer tissues of the patient groups were respectively 42.2, 45.6 and 51.1%, which were significantly higher than those in cancer-adjacent normal tissues of the control group (pcorrelation with age and tumor size (p>0.05). PCNA, Ki-67 and COX-2 expression in cancer tissues of the patient group had no correlation with the existence of lumps and localized density-increased shadows (p>0.05), but were associated with manifestations of architectural distortion, calcification as well as skin and nipple depression (pcorrelation analysis revealed that there was a significantly positive correlation between the expression of PCNA and COX-2 in cancer tissues of the patient group (r=0.676, pcorrelation between the expression of Ki-67 and COX-2 (r=0.724, pcorrelation with the expression of Ki-67 (p>0.05). In conclusion, PCNA, Ki-67 and COX-2 expression is of great significance in the occurrence, invasion and metastasis of breast invasive ductal carcinoma. There is a strong correlation between PCNA, Ki-67 and COX-2 expression levels and X-ray features in mammography in breast

Expressão de p53, p16 E COX-2 em carcinoma escamoso de esôfago e associação histopatológica p53, p16 E COX-2 expression in esophageal squamous cell carcinoma and histopathological association

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Izabella Paz Danezi Felin

2008-12-01

Full Text Available RACIONAL: O câncer de esôfago representa cerca de 2% dos tumores malignos e a terceira causa mais comum de câncer do trato gastrointestinal. A associação do prognóstico do câncer de esôfago com alguns marcadores imunoistoquímicos, como as proteínas p53, p16 e a ciclooxigenase 2 (COX-2 tem sido relatada. A detecção de marcadores moleculares através de imunoistoquímica pode ser utilizada para avaliação prognóstica. OBJETIVOS: Investigar a associação entre a expressão das proteínas p53, p16 e a COX-2 com o estádio do carcinoma escamoso de esôfago. MÉTODOS: Foram analisadas 31 amostras de ressecção cirúrgica por esofagectomia diagnosticadas como carcinoma de células escamosas de esôfago e 31 amostras não-tumorais referentes a cada caso. Realizou-se a revisão histopatológica e o estádio pTNM. Amostras tumorais e não-tumorais adjacentes foram submetidas a análise imunoistoquímica para avaliar o conteúdo das proteínas p53, p16 e COX-2. Foi considerada positiva a expressão nuclear para p53 em quantidade igual ou superior a 10,00% das células e presença da expressão citoplasmática de acordo com três escores (1, 2, 3 de intensidade (leve, moderada, acentuada de imunocoloração para COX-2. RESULTADOS: Em área tumoral, as análises revelaram 48,38% de positividade para p53, 16,12% de positividade para p16, e 100,00% de positividade escores 1+, 2+ ou 3+ para COX-2. No entanto, quando se avaliou possível relação da expressão destes marcadores com o estádio, apenas a COX-2, escore 3+ intensidade acentuada mostraram associação significativa. CONCLUSÃO: O presente estudo demonstrou que existe relação positiva entre a expressão de COX-2, escore 3+ e estádio mais avançado no carcinoma de esôfago.BACKGROUND: The esophageal carcinoma represents about 2% of malignant tumors and is the third most common cause of gastrointestinal cancer. The correlation between immunohistochemistry markers, such as p53, p16

Efek ekstrak daun singkong (Manihot utilissima terhadap ekspresi COX-2 pada monosit yang dipapar LPS E.coli (The effect of Manihot utilissima extracts on COX-2 expression of monocytes induced by LPS E. coli

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Zahara Meilawaty

2013-12-01

Full Text Available Background: Periodontal disease is a common and widespread disease in the community. Gram negative bacteria have a role inperiodontitis. These bacteria secrete a variety of products such as endotoxin lipopolysaccharide (LPS, which causes the occurrenceof inflammation or infection. The body defense responses are neutrophils and mononuclear cells (monocytes and macrophages. Inresponse to defense mechanism, the body will be expressed enzyme cyclooxygenase (COX which functions convert arachidonic acidto prostaglandins. Cassava leaf cells known to play a role in reducing inflammation, but the mechanism for inhibiting COX-2, is notknown. Purpose: The study was aimed to determine the effect of cassava leaf extract (Manihot utilissima on expression of enzyme COX-2 in monocytes which were exposed by LPS E. coli. Methods: This study was in vitro experimental studies with the design of posttestonly control group design. The sample was the cassava leaves extract (Manihot utilissima at concentration of 12.5 % and 25 %. Theexpression of COX-2 was determined by immunocytochemistry method. Isolated monocytes were incubated in cassava leaf extract, andthen exposed to LPS, after washing imunostaning procedure was performed using a monoclonal antibody (MAb anti-human COX-2.The research data was the number of monocytes that express COX-2. Results: Expression of COX-2 in the group cassava leaf extractwas higher than the group that induced by LPS E. coli only. Conclusion: Cassava leaf extract did not inhibit the expression of COX-2in monocytes which were exposed by LPS E. coli.Latar belakang: Penyakit periodontal merupakan penyakit umum dan tersebar luas di masyarakat. Bakteri yang banyak berperanpada periodontitis adalah Gram negatif. Bakteri ini mengeluarkan berbagai produk antara lain endotoksin lipopolisakarida (LPS yangmenyebabkan inflamasi atau infeksi. Respon pertahanan tubuh pertama adalah netrofil dan sel mononuklear (monosit dan makrofag.Pada respon

Thymoquinone inhibits phorbol ester-induced activation of NF-κB and expression of COX-2, and induces expression of cytoprotective enzymes in mouse skin in vivo

International Nuclear Information System (INIS)

Kundu, Joydeb Kumar; Liu, Lijia; Shin, Jun-Wan; Surh, Young-Joon

2013-01-01

Highlights: •Thymoquinone inhibits phorbol ester-induced COX-2 expression in mouse skin. •Thymoquinone attenuates phosphorylation of IκBα and DNA binding of NF-κB in mouse skin. •Thymoquinone inhibits phosphorylation of p38 MAP kinase, JNK and Akt in mouse skin. •Thymoquinone induces the expression of cytoprotective proteins in mouse skin. -- Abstract: Thymoquinone (TQ), the active ingredient of Nigella sativa, has been reported to possess anti-inflammatory and chemopreventive properties. The present study was aimed at elucidating the molecular mechanisms of anti-inflammatory and antioxidative activities of thymoquinone in mouse skin. Pretreatment of female HR-1 hairless mouse skin with TQ attenuated 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced expression of cyclooxygenase-2 (COX-2). TQ diminished nuclear translocation and the DNA binding of nuclear factor-kappaB (NF-κB) via the blockade of phosphorylation and subsequent degradation of IκBα in TPA-treated mouse skin. Pretreatment with TQ attenuated the phosphorylation of Akt, c-Jun-N-terminal kinase and p38 mitogen-activated protein kinase, but not that of extracellular signal-regulated kinase-1/2. Moreover, topical application of TQ induced the expression of heme oxygenase-1, NAD(P)H-quinoneoxidoreductase-1, glutathione-S-transferase and glutamate cysteine ligase in mouse skin. Taken together, the inhibitory effects of TQ on TPA-induced COX-2 expression and NF-κB activation, and its ability to induce the expression of cytoprotective proteins provide a mechanistic basis of anti-inflammatory and antioxidative effects of TQ in hairless mouse skin

COX-2 and p53 in human sinonasal cancer

DEFF Research Database (Denmark)

Holmila, Reetta; Cyr, Diane; Luce, Danièle

2008-01-01

The causal role of wood-dust exposure in sinonasal cancer (SNC) has been established in epidemiological studies, but the mechanisms of SNC carcinogenesis are still largely unknown. Increased amounts of COX-2 are found in both premalignant and malignant tissues, and experimental evidence link COX-2...... to development of cancer. Many signals that activate COX-2 also induce tumor suppressor p53, a transcription factor central in cellular stress response. We investigated COX-2 and p53 expressions by immunohistochemistry in 50 SNCs (23 adenocarcinomas, and 27 squamous cell carcinomas (SCC); 48 analyzed for COX-2...... displayed adenocarcinoma. COX-2 was expressed at higher levels in adenocarcinoma as compared to SSC (p COX-2 expression showed significant association with occupational exposure to wood dust (p = 0.024), and with nonsmoking status (p = 0.001). No statistically significant associations between...

Proteomic Analysis Shows Constitutive Secretion of MIF and p53-associated Activity of COX-2−/− Lung Fibroblasts

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Mandar Dave

2017-12-01

Full Text Available The differential expression of two closelyassociated cyclooxygenase isozymes, COX-1 and COX-2, exhibited functions beyond eicosanoid metabolism. We hypothesized that COX-1 or COX-2 knockout lung fibroblasts may display altered protein profiles which may allow us to further differentiate the functional roles of these isozymes at the molecular level. Proteomic analysis shows constitutive production of macrophage migration inhibitory factor (MIF in lung fibroblasts derived from COX-2−/− but not wild-type (WT or COX-1−/− mice. MIF was spontaneously released in high levels into the extracellular milieu of COX2−/− fibroblasts seemingly from the preformed intracellular stores, with no change in the basal gene expression of MIF. The secretion and regulation of MIF in COX-2−/− was “prostaglandin-independent.” GO analysis showed that concurrent with upregulation of MIF, there is a significant surge in expression of genes related to fibroblast growth, FK506 binding proteins, and isomerase activity in COX-2−/− cells. Furthermore, COX-2−/− fibroblasts also exhibit a significant increase in transcriptional activity of various regulators, antagonists, and co-modulators of p53, as well as in the expression of oncogenes and related transcripts. Integrative Oncogenomics Cancer Browser (IntroGen analysis shows downregulation of COX-2 and amplification of MIF and/or p53 activity during development of glioblastomas, ependymoma, and colon adenomas. These data indicate the functional role of the MIF-COX-p53 axis in inflammation and cancer at the genomic and proteomic levels in COX-2-ablated cells. This systematic analysis not only shows the proinflammatory state but also unveils a molecular signature of a pro-oncogenic state of COX-1 in COX-2 ablated cells.

Inhibition of COX-2 expression by topical diclofenac enhanced radiation sensitivity via enhancement of TRAIL in human prostate adenocarcinoma xenograft model

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2013-01-01

Background COX-2 inhibitors have an antitumor potential and have been verified by many researchers. Treatment of cancer cells with external stressors such as irradiation can stimulate the over-expression of COX-2 and possibly confer radiation resistance. In this study, we tested if topical diclofenac, which inhibits both COX-1 and COX-2, administration rendered prostate tumor cells sensitize to the effects of radiation. Methods LNCaP-COX-2 and LNCaP-Neo cells were treated with 0 to 1000 μM diclofenac. Next, a clonogenic assay was performed in which cells were subjected to irradiation (0 to 4 Gy) with or without diclofenac. COX-2 expression and other relevant molecules were measured by real-time PCR and immunohistochemistry after irradiation and diclofenac treatment. In addition, we assessed the tumor volumes of xenograft LNCaP-COX-2 cells treated with topical diclofenac with or without radiation therapy (RT). Results LNCaP-COX-2 and LNCaP-Neo cell lines experienced cytotoxic effects of diclofenac in a dose related manner. Clonogenic assays demonstrated that LNCaP-COX-2 cells were significantly more resistant to RT than LNCaP-Neo cells. Furthermore, the addition of diclofenac sensitized LNCaP-COX-2 not but LNCaP-Neo cells to the cytocidal effects of radiation. In LNCaP-COX-2 cells, diclofenac enhanced radiation-induced apoptosis compared with RT alone. This phenomenon might be attributed to enhancement of RT-induced TRAIL expression as demonstrated by real-time PCR analysis. Lastly, tumor volumes of LNCaP-COX-2 cells xenograft treated with diclofenac or RT alone was >4-fold higher than in mice treated with combined diclofenac and radiation (pdiclofenac enhances the effect of RT on prostate cancer cells that express COX-2. Thus, diclofenac may have potential as radiosensitizer for treatment of prostate cancer. PMID:23289871

Regulation of Cox-2 by Cyclic AMP Response Element Binding Protein in Prostate Cancer: Potential Role for Nexrutine

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Rita Ghosh

2007-11-01

Full Text Available We recently showed that NexrutineR, a Phellodendron amurense bark extract, suppresses proliferation of prostate cancer cell lines and tumor development in the transgenic adenocarcinoma of mouse prostate (TRAMP model. Our data also indicate that the antiproliferative effects of NexrutineR are mediated in part by Akt and Cyclic AMP response element binding protein (CREB. Cyclooxygenase (Cox-2, a pro-inflammatory mediator, is a CREB target that induces prostaglandin E2 (PGE2 and suppresses apoptosis. Treatment of LNCaP cells with NexrutineR reduced tumor necrosis factor α-induced enzymatic as well as promoter activities of Cox-2. NexrutineR also reduced the expression and promoter activity of Cox-2 in PC-3 cells that express high constitutive levels of Cox-2. Deletion analysis coupled with mutational analysis of the Cox-2 promoter identified CRE as being sufficient for mediating NexrutineR response. Immunohistochemical analysis of human prostate tumors show increased expression of CREB and DNA binding activity in high-grade tumors (three-fold higher in human prostate tumors compared to normal prostate; P = .01. We have identified CREB-mediated activation of Cox-2 as a potential signaling pathway in prostate cancer which can be blocked with a nontoxic, cost-effective dietary supplement like NexrutineR, demonstrating a prospective for development of NexrutineR for prostate cancer management.

The effects of a cyclooxygenase-2 (COX-2 expression and inhibition on human uveal melanoma cell proliferation and macrophage nitric oxide production

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Marshall Jean-Claude

2007-01-01

Full Text Available Abstract Background Cyclooxygenase-2 (COX-2 expression has previously been identified in uveal melanoma although the biological role of COX-2 in this intraocular malignancy has not been elucidated. This study aimed to investigate the effect of a COX-2 inhibitor on the proliferation rate of human uveal melanoma cells, as well as its effect on the cytotoxic response of macrophages. Methods Human uveal melanoma cell lines were transfected to constitutively express COX-2 and the proliferative rate of these cells using two different methods, with and without the addition of Amfenac, was measured. Nitric oxide production by macrophages was measured after exposure to melanoma-conditioned medium from both groups of cells as well as with and without Amfenac, the active metabolite of Nepafenac. Results Cells transfected to express COX-2 had a higher proliferation rate than those that did not. The addition of Amfenac significantly decreased the proliferation rate of all cell lines. Nitric oxide production by macrophages was inhibited by the addition of melanoma conditioned medium, the addition of Amfenac partially overcame this inhibition. Conclusion Amfenac affected both COX-2 transfected and non-transfected uveal melanoma cells in terms of their proliferation rates as well as their suppressive effects on macrophage cytotoxic activity.

The cardiac copper chaperone proteins Sco1 and CCS are up-regulated, but Cox 1 and Cox4 are down-regulated, by copper deficiency.

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Getz, Jean; Lin, Dingbo; Medeiros, Denis M

2011-10-01

Copper is ferried in a cell complexed to chaperone proteins, and in the heart much copper is required for cytochrome c oxidase (Cox). It is not completely understood how copper status affects the levels of these proteins. Here we determined if dietary copper deficiency could up- or down-regulate select copper chaperone proteins and Cox subunits 1 and 4 in cardiac tissue of rats. Sixteen weanling male Long-Evans rats were randomized into treatment groups, one group receiving a copper-deficient diet (CCS, Sco1, Ctr1, Cox17, Cox1, and Cox4 by SDS-PAGE and Western blotting. No changes were observed in the concentrations of CTR1 and Cox17 between copper-adequate and copper-deficient rats. CCS and Sco1 were up-regulated and Cox1 and Cox4 were both down-regulated as a result of copper deficiency. These data suggest that select chaperone proteins and may be up-regulated, and Cox1 and 4 down-regulated, by a dietary copper deficiency, whereas others appear not to be affected by copper status.

Cyclooxygenase-2 up-regulates CCR7 expression via AKT-mediated phosphorylation and activation of Sp1 in breast cancer cells.

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Chuang, Chun-Wei; Pan, Mei-Ren; Hou, Ming-Feng; Hung, Wen-Chun

2013-02-01

Up-regulation of cyclooxygenase-2 (COX-2) is frequently found in human cancers and is significantly associated with tumor metastasis. Our previous results demonstrate that COX-2 and its metabolite prostaglandin E2 (PGE2) stimulate the expression of CCR7 chemokine receptor via EP2/EP4 receptors to promote lymphatic invasion in breast cancer cells. In this study, we address the underlying mechanism of COX-2/PGE2-induced CCR7 expression. We find that COX-2/PGE2 increase CCR7 expression via the AKT signaling pathway in breast cancer cells. Promoter deletion and mutation assays identify the Sp1 site located at the -60/-57 region of CCR7 gene promoter is critical for stimulation. Chromatin immunoprecipitation (ChIP) assay confirms that in vivo binding of Sp1 to human CCR7 promoter is increased by COX-2 and PGE2. Knockdown of Sp1 by shRNA reduces the induction of CCR7 by PGE2. We demonstrate for the first time that AKT may directly phosphorylate Sp1 at S42, T679, and S698. Phosphorylation-mimic Sp1 protein harboring S42D, T679D, and S698D mutation strongly activates CCR7 expression. In contrast, change of these three residues to alanine completely blocks the induction of CCR7 by PGE2. Pathological investigation demonstrates that CCR7 expression is strongly associated with phospho-AKT and Sp1 in 120 breast cancer tissues. Collectively, our results demonstrate that COX-2 up-regulates CCR7 expression via AKT-mediated phosphorylation and activation of Sp1 and this pathway is highly activated in metastatic breast cancer. Copyright © 2012 Wiley Periodicals, Inc.

Immunohistochemical and morphometric evaluation of COX 1 and COX-2 in the remodeled lung in idiopathic pulmonary fibrosis and systemic sclerosis

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Edwin Roger Parra

2013-12-01

Full Text Available OBJECTIVE: To study the expression of COX-1 and COX-2 in the remodeled lung in systemic sclerosis (SSc and idiopathic pulmonary fibrosis (IPF patients, correlating that expression with patient survival.METHODS: We examined open lung biopsy specimens from 24 SSc patients and 30 IPF patients, using normal lung tissue as a control. The histological patterns included fibrotic nonspecific interstitial pneumonia (NSIP in SSc patients and usual interstitial pneumonia (UIP in IPF patients. We used immunohistochemistry and histomorphometry to evaluate the expression of COX-1 and COX-2 in alveolar septa, vessels, and bronchioles. We then correlated that expression with pulmonary function test results and evaluated its impact on patient survival.RESULTS: The expression of COX-1 and COX-2 in alveolar septa was significantly higher in IPF-UIP and SSc-NSIP lung tissue than in the control tissue. No difference was found between IPF-UIP and SSc-NSIP tissue regarding COX-1 and COX-2 expression. Multivariate analysis based on the Cox regression model showed that the factors associated with a low risk of death were younger age, high DLCO/alveolar volume, IPF, and high COX-1 expression in alveolar septa, whereas those associated with a high risk of death were advanced age, low DLCO/alveolar volume, SSc (with NSIP, and low COX-1 expression in alveolar septa.CONCLUSIONS: Our findings suggest that strategies aimed at preventing low COX-1 synthesis will have a greater impact on SSc, whereas those aimed at preventing high COX-2 synthesis will have a greater impact on IPF. However, prospective randomized clinical trials are needed in order to confirm that.

Prognostic implications of tumor volume response and COX-2 expression change during radiotherapy in cervical cancer patients

International Nuclear Information System (INIS)

Noh, Jae Myoung; Park, Won; Huh, Seung Jae; Cho, Eun Yoon; Choi, Yoon La; Bae, Duk Soo; Kim, Byoung Gie

2012-01-01

The relationship between treatment outcomes, alteration of the expression of biological markers, and tumor volume response during radiotherapy (RT) in patients with uterine cervical cancer was analyzed. Twenty patients with cervical squamous cell carcinoma received definitive RT with (n = 17) or without (n = 3) concurrent chemotherapy. Tumor volumes were measured by three serial magnetic resonance imaging scans at pre-, mid-, and post-RT. Two serial punch biopsies were performed at pre- and mid-RT, and immunohistochemical staining for cyclooxygenase (COX)-2 and epidermal growth factor receptor was performed. The median follow-up duration was 60 months. The median tumor volume response at mid-RT (V2R) was 0.396 (range, 0.136 to 0.983). At mid-RT, an interval increase in the distribution of immunoreactivity for COX-2 was observed in 8 patients, and 6 of them showed poor mid-RT tumor volume response (V2R ≥ 0.4). Four (20%) patients experienced disease progression after 10 to 12 months (median, 11 months). All 4 patients had poor mid-RT tumor volume response (p = 0.0867) and 3 of them had an interval increase in COX-2 expression. Overall survival (OS) and progression-free survival (PFS) decreased in patients with V2R ≥ 0.4 (p 0.0291 for both). An interval increase in COX-2 expression at mid-RT was also associated with a decreased survival (p = 0.1878 and 0.1845 for OS and PFS, respectively). Poor tumor volume response and an interval increase in COX-2 expression at mid-RT decreased survival outcomes in patients with uterine cervical cancer.

Effect of Ginkgo biloba extract on the expressions of Cox-2 and GST ...

African Journals Online (AJOL)

2014-03-01

Mar 1, 2014 ... Its underlying biological mechanism remains unclear and no well-documented drug and ... Objectives: To explore the effect of EGb on expressions of cyclooxygenase-2 (Cox-2) and glutathione S-transferase Pi. (GST-Pi) in the ..... in an animal model of Parkinson's disease: Therapeutic perspectives. Nutri-.

Integrated proteomics identified novel activation of dynein IC2-GR-COX-1 signaling in neurofibromatosis type I (NF1) disease model cells.

Science.gov (United States)

Hirayama, Mio; Kobayashi, Daiki; Mizuguchi, Souhei; Morikawa, Takashi; Nagayama, Megumi; Midorikawa, Uichi; Wilson, Masayo M; Nambu, Akiko N; Yoshizawa, Akiyasu C; Kawano, Shin; Araki, Norie

2013-05-01

Neurofibromatosis type 1 (NF1) tumor suppressor gene product, neurofibromin, functions in part as a Ras-GAP, and though its loss is implicated in the neuronal abnormality of NF1 patients, its precise cellular function remains unclear. To study the molecular mechanism of NF1 pathogenesis, we prepared NF1 gene knockdown (KD) PC12 cells, as a NF1 disease model, and analyzed their molecular (gene and protein) expression profiles with a unique integrated proteomics approach, comprising iTRAQ, 2D-DIGE, and DNA microarrays, using an integrated protein and gene expression analysis chart (iPEACH). In NF1-KD PC12 cells showing abnormal neuronal differentiation after NGF treatment, of 3198 molecules quantitatively identified and listed in iPEACH, 97 molecules continuously up- or down-regulated over time were extracted. Pathway and network analysis further revealed overrepresentation of calcium signaling and transcriptional regulation by glucocorticoid receptor (GR) in the up-regulated protein set, whereas nerve system development was overrepresented in the down-regulated protein set. The novel up-regulated network we discovered, "dynein IC2-GR-COX-1 signaling," was then examined in NF1-KD cells. Validation studies confirmed that NF1 knockdown induces altered splicing and phosphorylation patterns of dynein IC2 isomers, up-regulation and accumulation of nuclear GR, and increased COX-1 expression in NGF-treated cells. Moreover, the neurite retraction phenotype observed in NF1-KD cells was significantly recovered by knockdown of the dynein IC2-C isoform and COX-1. In addition, dynein IC2 siRNA significantly inhibited nuclear translocation and accumulation of GR and up-regulation of COX-1 expression. These results suggest that dynein IC2 up-regulates GR nuclear translocation and accumulation, and subsequently causes increased COX-1 expression, in this NF1 disease model. Our integrated proteomics strategy, which combines multiple approaches, demonstrates that NF1-related neural

Effect of Ginkgo biloba extract on the expressions of Cox-2 and GST ...

African Journals Online (AJOL)

Objectives: This study was performed to explore the effect of EGb on expressions of cyclooxygenase-2 (Cox-2) and glutathione S-transferase Pi (GST-Pi) in the pathogenesis of HCC risk. Methods: 120 Wistar rats were divided into three groups at random: normal control group (control group), HCC risk group without ...

Posttranscriptional Regulation of Cyclooxygenase-2 in Rat Intestinal Epithelial Cells

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Zhonghua Zhang

2000-01-01

Full Text Available Modulation of cyclooxygenase-2 (COX-2 mRNA stability plays an important role in the regulation of its expression by oncogenic Ras. Here, we evaluate COX-2 mRNA stability in response to treatment with two known endogenous promoters of gastrointestinal cancer, the bile acid (chenodeoxycholate; CD and ceramide. Treatment with CD and ceramide resulted in a 10-fold increase in the level of COX-2 protein and a four-fold lengthening of the half-life of COX-2 mRNA. COX-2 mRNA stability was assessed by Northern blot analysis and by evaluating the AU-rich element located in the COX-2 3′-UTR. A known inhibitor of mitogen-activated protein (MAP/extracellular signal-regulated kinase (ERK kinase (MEK, PD98059, reversed the effects of CD or ceramide to stabilize COX-2 mRNA. Overexpression of a dominant-negative ERK-1 or ERK-2 protein also led to destabilization of COX-2 mRNA. Treatment with a p38 MAPK inhibitor, PD169316, or transfection with a dominant-negative p38 MAPK construct reversed the effect of CD or ceramide to stabilize COX-2 mRNA. Expression of a dominant-negative c-Jun N-terminal kinase (JNK had no effect on COX-2 mRNA stability in cells treated with CD or ceramide. We conclude that posttranscriptional mechanisms play an important role in the regulation of COX-2 expression during carcinogenesis.

Effusanin E suppresses nasopharyngeal carcinoma cell growth by inhibiting NF-κB and COX-2 signaling.

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Mingzhu Zhuang

Full Text Available Rabdosia serra is well known for its antibacterial, anti-inflammatory and antitumor activities, but no information has been available for the active compounds derived from this plant in inhibiting human nasopharyngeal carcinoma (NPC cell growth. In this study, we isolated and purified a natural diterpenoid from Rabdosia serra and identified its chemical structure as effusanin E and elucidated its underlying mechanism of action in inhibiting NPC cell growth. Effusanin E significantly inhibited cell proliferation and induced apoptosis in NPC cells. Effusanin E also induced the cleavage of PARP, caspase-3 and -9 proteins and inhibited the nuclear translocation of p65 NF-κB proteins. Moreover, effusanin E abrogated the binding of NF-κB to the COX-2 promoter, thereby inhibiting the expression and promoter activity of COX-2. Pretreatment with a COX-2 or NF-κB-selective inhibitor (celecoxib or ammonium pyrrolidinedithiocarbamate had an additive effect on the effusanin E-mediated inhibition of proliferation, while pretreatment with an activator of NF-κB/COX-2 (lipopolysaccharides abrogated the effusanin E-mediated inhibition of proliferation. Effusanin E also significantly suppressed tumor growth in a xenograft mouse model without obvious toxicity, furthermore, the expression of p50 NF-κB and COX-2 were down-regulated in the tumors of nude mice. These data suggest that effusanin E suppresses p50/p65 proteins to down-regulate COX-2 expression, thereby inhibiting NPC cell growth. Our findings provide new insights into exploring effusanin E as a potential therapeutic compound for the treatment of human nasopharyngeal carcinoma.

Lung Myofibroblasts Are Characterized by Down-Regulated Cyclooxygenase-2 and Its Main Metabolite, Prostaglandin E2

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Gabasa, Marta; Royo, Dolores; Molina-Molina, Maria; Roca-Ferrer, Jordi; Pujols, Laura; Picado, Cesar

2013-01-01

Background Prostaglandin E2 (PGE2), the main metabolite of cyclooxygenase (COX), is a well-known anti-fibrotic agent. Moreover, myofibroblasts expressing α-smooth muscle actin (α-SMA), fibroblast expansion and epithelial-mesenchymal transition (EMT) are critical to the pathogenesis of idiopathic pulmonary fibrosis (IPF). Our aim was to investigate the expression of COX-2 and PGE2 in human lung myofibroblasts and establish whether fibroblast-myofibroblast transition (FMT) and EMT are associated with COX-2 and PGE2 down-regulation. Methods Fibroblasts obtained from IPF patients (n = 6) and patients undergoing spontaneous pneumothorax (control, n = 6) and alveolar epithelial cell line A549 were incubated with TGF-β1 and FMT and EMT markers were evaluated. COX-2 and α-SMA expression, PGE2 secretion and cell proliferation were measured after IL-1β and PGE2 incubation. Results Myofibroblasts from both control and IPF fibroblast cultures stimulated with IL-1β showed no COX-2 expression. IPF fibroblasts showed increased myofibroblast population and reduced COX-2 expression in response to IL-1β. TGF-β1 increased the number of myofibroblasts in a time-dependent manner. In contrast, TGF-β1 induced slight COX-2 expression at 4 h (without increase in myofibroblasts) and 24 h, but not at 72 h. Both IPF and control cultures incubated with TGF-β1 for 72 h showed diminished COX-2 induction, PGE2 secretion and α-SMA expression after IL-1β addition. The latter decreased proliferation in fibroblasts but not in myofibroblasts. A549 cells incubated with TGF-β1 for 72 h showed down-regulated COX-2 expression and low basal PGE2 secretion in response to IL-1β. Immuno-histochemical analysis of IPF lung tissue showed no COX-2 immuno-reactivity in myofibroblast foci. Conclusions Myofibroblasts are associated with COX-2 down-regulation and reduced PGE2 production, which could be crucial in IPF development and progression. PMID:23755232

Adverse Effects of COX-2 Inhibitors

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Jagdish N. Sharma

2005-01-01

Full Text Available Cyclooxygenase-2 selective inhibitors (COXIBs were developed with the prime object of minimizing gastrointestinal adverse effects, which are seen with the use of traditional nonsteroidal anti-inflammatory drugs (NSAIDs. Their long-term use is limited by the development of hypertension, edema, and congestive heart failure in a significant proportion of patients. NSAIDs block the activity of both COX isozymes, COX-1 and COX-2, which mediate the enzymatic conversion of arachidonate to prostaglandin H2 (PGH2 and other prostaglandin (PG metabolites. It is well established that the cardiovascular profile of COX-2 inhibitors can be accounted for by inhibition of COX-dependent PG synthesis. Following the COX-mediated synthesis of PGH2 from arachidonate, PGH2 is metabolized to one of at least five bioactive PGs, including PGE2, PGI2, PGF2, PGD2, or thromboxane A2 (TXA2. These prostanoids have pleiotropic cardiovascular effects, altering platelet function and renal function, and they are acting either as vasodilators or vasoconstrictors. Although COX-1 and COX-2 exhibit similar biochemical activity in converting arachidonate to PGH2in vitro, the ultimate prostanoids they produce in vivo may be different due to differential regulation of COX-1 and COX-2, tissue distribution, and availability of the prostanoid synthases. PGs have been established as being critically involved in mitigating hypertension, helping to maintain medullary blood flow (MBF, promoting urinary salt excretion, and preserving the normal homeostasis of thrombosis, and the researchers found that the use of COX-2 inhibitors caused many serious complications in altering the normal body homeostasis. The purpose of the present research is to explain briefly the side effects of COX-2 inhibitors on the renal and cardiovascular system.

Antitumor effects of celecoxib in COX-2 expressing and non-expressing canine melanoma cell lines.

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Seo, Kyoung-Won; Coh, Ye-Rin; Rebhun, Robert B; Ahn, Jin-Ok; Han, Sei-Myung; Lee, Hee-Woo; Youn, Hwa-Young

2014-06-01

Cyclooxygenase-2 (COX-2) is a potential target for chemoprevention and cancer therapy. Celecoxib, a selective COX-2 inhibitor, inhibits cell growth of various types of human cancer including malignant melanoma. In dogs, oral malignant melanoma represents the most common oral tumor and is often a fatal disease. Therefore, there is a desperate need to develop additional therapeutic strategies. The purpose of this study was to investigate the anticancer effects of celecoxib on canine malignant melanoma cell lines that express varying levels of COX-2. Celecoxib induced a significant anti-proliferative effect in both LMeC and CMeC-1 cells. In the CMeC cells, treatment of 50 μM celecoxib caused an increase in cells in the G0/G1 and a decreased proportion of cells in G-2 phase. In the LMeC cells, 50 μM of celecoxib led to an increase in the percentage of cells in the sub-G1 phase and a significant activation of caspase-3 when compared to CMeC-1 cells. In conclusion, these results demonstrate that celecoxib exhibits antitumor effects on canine melanoma LMeC and CMeC-1 cells by induction of G1-S cell cycle arrest and apoptosis. Our data suggest that celecoxib might be effective as a chemotherapeutic agent against canine malignant melanoma. Copyright © 2014. Published by Elsevier Ltd.

FOXP3 inhibits cancer stem cell self-renewal via transcriptional repression of COX2 in colorectal cancer cells.

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Liu, Shuo; Zhang, Cun; Zhang, Kuo; Gao, Yuan; Wang, Zhaowei; Li, Xiaoju; Cheng, Guang; Wang, Shuning; Xue, Xiaochang; Li, Weina; Zhang, Wei; Zhang, Yingqi; Xing, Xianghui; Li, Meng; Hao, Qiang

2017-07-04

Colon cancer stem cell (cCSC) is considered as the seed cell of colon cancer initiation and metastasis. Cyclooxygenase-2 (COX2), a downstream target of NFκB, is found to be essential in promoting cancer stem cell renewal. However, how COX2 is dysregulated in cCSCs is largely unknown. In this study, we found that the expression of transcription factor FOXP3 was much lower in the spheroids than that in the parental tumor cells. Overexpression of FOXP3 significantly decreased the numbers of spheres, reduced the side population. Accordingly, FOXP3 expression decreased the tumor size and weight in the xenograft model. The tumor inhibitory effects of FOXP3 were rarely seen when COX2 was additionally knocked down. Mechanically, FOXP3 transcriptionally repressed COX2 expression via interacting with and thus inhibiting p65 activity on the putative NFκB response elements in COX2 promoter. Taken together, we here revealed possible involvement of FOXP3 in regulating cCSC self-renewal via tuning COX2 expression, and thus providing a new target for the eradication of colon cancer stem cells.

Acute upregulation of COX-2 by renal artery stenosis

DEFF Research Database (Denmark)

Mann, Birgitte; Hartner, A; Jensen, B L

2001-01-01

This study aimed to characterize the influence of acute renal artery stenosis on cyclooxygenase-2 (COX-2) and renin expression in the juxtaglomerular apparatus. For this purpose, male Sprague-Dawley rats received a left renal artery clip, and COX-2 mRNA, COX-2 immunoreactivity, plasma renin...... activity, and renin mRNA levels were determined. COX-2 mRNA and COX-2 immunoreactivity in the macula densa region in the clipped kidneys increased as early as 6 h after clipping and reached a maximal expression 1-2 days after clipping. Although values for plasma renin activity were elevated markedly at all...... time points examined, remaining renin mRNA levels were unchanged after 6 h and then increased to reach a maximum value 1-2 days after clipping. In the contralateral intact kidney, renin mRNA and COX-2 immunoreactivity decreased to approximately 50% of their normal values. To investigate a possible...

Genistein inhibits phorbol ester-induced NF-κB transcriptional activity and COX-2 expression by blocking the phosphorylation of p65/RelA in human mammary epithelial cells

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Chung, Myung-Hoon; Kim, Do-Hee [Research Institute for Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul (Korea, Republic of); Na, Hye-Kyung [Department of Food and Nutrition, Sungshin Women' s University, Seoul (Korea, Republic of); Kim, Jung-Hwan; Kim, Ha-Na [Research Institute for Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul (Korea, Republic of); Haegeman, Guy [LEGEST, University of Gent (Belgium); Surh, Young-Joon, E-mail: surh@snu.ac.kr [Research Institute for Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul (Korea, Republic of); Department of Molecular Medicine and Biopharmaceutical Sciences, Graduate School of Convergence Science and Technology, Seoul (Korea, Republic of); Cancer Research Institute, Seoul National University, Seoul (Korea, Republic of)

2014-10-15

Genistein, an isoflavone present in soy products, has chemopreventive effects on mammary carcinogenesis. In the present study, we have investigated the effects of genistein on phorbol ester-induced expression of cyclooxygenase-2 (COX-2) that plays an important role in the pathophysiology of inflammation-associated carcinogenesis. Pretreatment of cultured human breast epithelial (MCF10A) cells with genistein reduced COX-2 expression induced by 12-O-tetradecanoylphorbol-13-acetate (TPA). There are multiple lines of evidence supporting that the induction of COX-2 is regulated by the eukaryotic transcription factor NF-κB. Genistein failed to inhibit TPA-induced nuclear translocation and DNA binding of NF-κB as well as degradation of IκB. However, genistein abrogated the TPA-induced transcriptional activity of NF-κB as determined by the luciferase reporter gene assay. Genistein inhibited phosphorylation of the p65 subunit of NF-κB and its interaction with cAMP regulatory element-binding protein-binding protein (CBP)/p300 and TATA-binding protein (TBP). TPA-induced NF-κB phosphorylation was abolished by pharmacological inhibition of extracellular signal-regulated kinase (ERK). Likewise, pharmacologic inhibition or dominant negative mutation of ERK suppressed phosphorylation of p65. The above findings, taken together, suggest that genistein inhibits TPA-induced COX-2 expression in MCF10A cells by blocking ERK-mediated phosphorylation of p65 and its subsequent interaction with CBP and TBP.

Nuclear factor κB (NFκB) and cyclooxygenase-2 (Cox-2) expression in the irradiated colorectum is associated with subsequent histopathological changes

International Nuclear Information System (INIS)

Yeoh, Ann S.J.; Bowen, Joanne M.; Gibson, Rachel J.; Keefe, Dorothy M.K.

2005-01-01

Purpose: Recent studies have proposed that mucositis development is the same throughout the gastrointestinal tract (GIT), as it is formed from one structure embryologically. Radiation-induced oral mucositis studies have outlined the key involvement of nuclear factor κB (NFκB) and cyclooxygenase-2 (Cox-2) in its pathobiology. The purpose of this study was therefore to investigate the expression of NFκB and Cox-2 in the irradiated colorectum and to correlate these with the associated histopathologic changes. Methods and Materials: Colorectal tissues from 28 colorectal cancer patients treated with preoperative radiotherapy were analyzed for histopathologic changes using a variety of tissue staining methods. The expression of NFκB and Cox-2 in these tissues was investigated using immunohistochemistry. Changes in expression of these proteins were then correlated with the histopathologic changes. Results: Radiation therapy caused injury to the normal colorectal tissue surrounding tumor site, particularly around the blood vessels. These changes were reflected in changes in NFκB and Cox-2 expression. Conclusions: We conclude that different regions of the GIT, the colorectum, and oral cavity have similar underlying mechanisms of radiation-induced mucositis. Understanding these mechanisms will allow new approaches to be developed to specifically target steps in the evolution of alimentary mucositis

Prostacyclin synthase expression and epigenetic regulation in nonsmall cell lung cancer.

LENUS (Irish Health Repository)

Cathcart, Mary-Clare

2012-02-01

BACKGROUND: Prostacyclin synthase (PGIS) metabolizes prostaglandin H(2), into prostacyclin. This study aimed to determine the expression profile of PGIS in nonsmall cell lung cancer (NSCLC) and examine potential mechanisms involved in PGIS regulation. METHODS: PGIS expression was examined in human NSCLC and matched controls by reverse transcriptase polymerase chain reaction (RT-PCR), Western analysis, and immunohistochemistry. A 204-patient NSCLC tissue microarray was stained for PGIS and cyclooxygenase 2 (COX2) expression. Staining intensity was correlated with clinical parameters. Epigenetic mechanisms underpinning PGIS promoter expression were examined using RT-PCR, methylation-specific PCR, and chromatin immunoprecipitation analysis. RESULTS: PGIS expression was reduced\\/absent in human NSCLC protein samples (P < .0001), but not mRNA relative to matched controls. PGIS tissue expression was higher in squamous cell carcinoma (P = .004) and in male patients (P < .05). No significant correlation of PGIS or COX2 expression with overall patient survival was observed, although COX2 was prognostic for short-term (2-year) survival (P < .001). PGIS mRNA expression was regulated by DNA CpG methylation and histone acetylation in NSCLC cell lines, with chromatin remodeling taking place directly at the PGIS gene. PGIS mRNA expression was increased by both demethylation agents and histone deacetylase inhibitors. Protein levels were unaffected by demethylation agents, whereas PGIS protein stability was negatively affected by histone deacetylase inhibitors. CONCLUSIONS: PGIS protein expression is reduced in NSCLC, and does not correlate with overall patient survival. PGIS expression is regulated through epigenetic mechanisms. Differences in expression patterns between mRNA and protein levels suggest that PGIS expression and protein stability are regulated post-translationally. PGIS protein stability may have an important therapeutic role in NSCLC.

Flavonoids targeting of IκB phosphorylation abrogates carcinogen-induced MMP-9 and COX-2 expression in human brain endothelial cells

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Tahanian E

2011-05-01

Full Text Available Elizabeth Tahanian¹, Luis Arguello Sanchez¹, Tze Chieh Shiao², René Roy², Borhane Annabi¹¹Centre de Recherche BioMED, ²Centre de Recherche PharmaQAM, Département de chimie, Université du Québec à Montréal, QC, CanadaAbstract: Brain endothelial cells play an essential role as structural and functional components of the blood–brain barrier (BBB. Increased BBB breakdown and brain injury are associated with neuroinflammation and are thought to trigger mechanisms involving matrix metalloproteinase upregulation. Emerging evidence also indicates that cyclooxygenase (COX inhibition limits BBB disruption, but the mechanisms linking metalloproteinase to COX remain unknown. In this study, we sought to investigate the nuclear factor-kappa B (NF-κB signaling pathway, a common pathway in both the regulation of matrix metalloproteinase-9 (MMP-9 and COX-2 expression, and the inhibitory properties of several chemopreventive flavonoids. Human brain microvascular endothelial cells were treated with a combination of phorbol 12-myristate 13-acetate (PMA, a carcinogen documented to increase MMP-9 and COX-2 through NF-κB, and several naturally occurring flavonoids. Among the molecules tested, we found that fisetin, apigenin, and luteolin specifically and dose-dependently antagonized PMA-induced COX-2 and MMP-9 gene and protein expressions as assessed by qRT-PCR, immunoblotting, and zymography respectively. We further demonstrate that flavonoids impact on IκK-mediated phosphorylation activity as demonstrated by the inhibition of PMA-induced IκB phosphorylation levels. Our results suggest that BBB disruption during neuroinflammation could be pharmacologically reduced by a specific class of flavonoids acting as NF-κB signal transduction inhibitors.Keywords: blood–brain barrier, flavonoids, neuroinflammation, NF-κB signal transduction inhibitors

Effect of Helicobacter pylori infection on IL-8, IL-1beta and COX-2 expression in patients with chronic gastritis and gastric cancer.

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Bartchewsky, Waldemar; Martini, Mariana Rocha; Masiero, Mariana; Squassoni, Aline Candido; Alvarez, Marisa Claudia; Ladeira, Marcelo Sady; Salvatore, Daisy; Trevisan, Miriam; Pedrazzoli, José; Ribeiro, Marcelo Lima

2009-01-01

Helicobacter pylori infection is related to gastric cancer development, and chronic inflammation is presumed to be the main cause. The aim of the present study was to evaluate the influence of H. pylori cagA, vacA, iceA, and babA genotypes on COX-2, IL-1beta, and IL-8 expression. Of the 217 patients included in the study, 26 were uninfected, 127 had chronic gastritis and were H. pylori-positive, and 64 had gastric cancer. Bacterial genotypes were evaluated by polymerase chain reaction (PCR), and the expression values were determined by quantitative real-time PCR and immunohistochemistry. An association was found between the infection with cagA, vacA s1m1 strains and gastric cancer development. Regarding the 3' region of the cagA gene, we also found an association between the infection with cagA EPIYA-ABCCC strains and clinical outcome. Higher levels of IL-8, IL-1beta, and COX-2 were detected in gastric mucosa from infected patients with chronic gastritis, and they were also associated with the infection by cagA, vacA s1m1 strains. The IL-8 and IL-1beta levels decrease significantly from chronic gastritis to gastric cancer, while the relative expression remained unaltered when COX-2 expression was analyzed among patients with gastritis and cancer. Since inflammatory response to H. pylori infection plays an important role in cellular proliferation and gastric mucosal damage, the up-regulation of IL-1beta, IL-8, and COX-2 in patients with chronic gastritis has an important clinical implication in gastric carcinogenesis.

COX-2 and PPARγ expression are potential markers of recurrence risk in mammary duct carcinoma in-situ

International Nuclear Information System (INIS)

Kulkarni, Swati; Patil, Deepa B; Diaz, Leslie K; Wiley, Elizabeth L; Morrow, Monica; Khan, Seema A

2008-01-01

In women with duct carcinoma in-situ (DCIS) receiving breast conservation therapy (BCT), in-breast recurrences are seen in approximately 10%, but cannot be accurately predicted using clinical and histological criteria. We performed a case-control study to identify protein markers of local recurrence risk in DCIS. Women treated for DCIS with BCT, who later developed in-breast recurrence (cases) were matched by age and year of treatment to women who remained free of recurrence (controls). A total of 69 women were included in the study, 31 cases and 38 controls. Immunohistochemical evaluation of DCIS tissue arrays was performed for estrogen receptor, progesterone receptor, HER-2/neu, cyclin D1, p53, p21, cycloxygenase-2 (COX-2) and peroxisome proliferator activated receptor γ (PPARγ). Two markers were significantly different between cases and controls on univariate analysis: strong COX-2 expression was associated with increased risk of recurrence, with 67% vs. 24% positivity in cases and controls p = 0.006; and nuclear expression of PPARγ was associated with protection from recurrence with 4% vs. 27% positivity in cases and controls, p = 0.024. In a multivariate model which included size, grade, COX-2 and PPARγ positivity, we found COX-2 positivity to be a strong independent risk factor for recurrence (OR 7.90, 95% CI 1.72–36.23)., whereas size and grade were of borderline significance. PPARγ expression continued to demonstrate a protective trend, (OR 0.14, 95% CI 0.06–1.84). Our findings suggest that COX-2 and PPARγ should be investigated further as biologic markers to predict DCIS recurrence, particularly since they are also potential therapeutic targets

Cell-type-specific roles for COX-2 in UVB-induced skin cancer

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Herschman, Harvey

2014-01-01

In human tumors, and in mouse models, cyclooxygenase-2 (COX-2) levels are frequently correlated with tumor development/burden. In addition to intrinsic tumor cell expression, COX-2 is often present in fibroblasts, myofibroblasts and endothelial cells of the tumor microenvironment, and in infiltrating immune cells. Intrinsic cancer cell COX-2 expression is postulated as only one of many sources for prostanoids required for tumor promotion/progression. Although both COX-2 inhibition and global Cox-2 gene deletion ameliorate ultraviolet B (UVB)-induced SKH-1 mouse skin tumorigenesis, neither manipulation can elucidate the cell type(s) in which COX-2 expression is required for tumorigenesis; both eliminate COX-2 activity in all cells. To address this question, we created Cox-2 flox/flox mice, in which the Cox-2 gene can be eliminated in a cell-type-specific fashion by targeted Cre recombinase expression. Cox-2 deletion in skin epithelial cells of SKH-1 Cox-2 flox/flox;K14Cre + mice resulted, following UVB irradiation, in reduced skin hyperplasia and increased apoptosis. Targeted epithelial cell Cox-2 deletion also resulted in reduced tumor incidence, frequency, size and proliferation rate, altered tumor cell differentiation and reduced tumor vascularization. Moreover, Cox-2 flox/flox;K14Cre + papillomas did not progress to squamous cell carcinomas. In contrast, Cox-2 deletion in SKH-1 Cox-2 flox/flox; LysMCre + myeloid cells had no effect on UVB tumor induction. We conclude that (i) intrinsic epithelial COX-2 activity plays a major role in UVB-induced skin cancer, (ii) macrophage/myeloid COX-2 plays no role in UVB-induced skin cancer and (iii) either there may be another COX-2-dependent prostanoid source(s) that drives UVB skin tumor induction or there may exist a COX-2-independent pathway(s) to UVB-induced skin cancer. PMID:24469308

Global gene expression analysis of canine osteosarcoma stem cells reveals a novel role for COX-2 in tumour initiation.

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Pang, Lisa Y; Gatenby, Emma L; Kamida, Ayako; Whitelaw, Bruce A; Hupp, Ted R; Argyle, David J

2014-01-01

Osteosarcoma is the most common primary bone tumour of both children and dogs. It is an aggressive tumour in both species with a rapid clinical course leading ultimately to metastasis. In dogs and children distant metastasis occurs in >80% of individuals treated by surgery alone. Both canine and human osteosarcoma has been shown to contain a sub-population of cancer stem cells (CSCs), which may drive tumour growth, recurrence and metastasis, suggesting that naturally occurring canine osteosarcoma could act as a preclinical model for the human disease. Here we report the successful isolation of CSCs from primary canine osteosarcoma, as well as established cell lines. We show that these cells can form tumourspheres, and demonstrate relative resistance to chemotherapy. We demonstrate similar results for the human osteosarcma cell lines, U2OS and SAOS2. Utilizing the Affymetrix canine microarray, we are able to definitively show that there are significant differences in global gene expression profiles of isolated osteosarcoma stem cells and the daughter adherent cells. We identified 13,221 significant differences (p = 0.05), and significantly, COX-2 was expressed 141-fold more in CSC spheres than daughter adherent cells. To study the role of COX-2 expression in CSCs we utilized the COX-2 inhibitors meloxicam and mavacoxib. We found that COX-2 inhibition had no effect on CSC growth, or resistance to chemotherapy. However inhibition of COX-2 in daughter cells prevented sphere formation, indicating a potential significant role for COX-2 in tumour initiation.

Global gene expression analysis of canine osteosarcoma stem cells reveals a novel role for COX-2 in tumour initiation.

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Lisa Y Pang

Full Text Available Osteosarcoma is the most common primary bone tumour of both children and dogs. It is an aggressive tumour in both species with a rapid clinical course leading ultimately to metastasis. In dogs and children distant metastasis occurs in >80% of individuals treated by surgery alone. Both canine and human osteosarcoma has been shown to contain a sub-population of cancer stem cells (CSCs, which may drive tumour growth, recurrence and metastasis, suggesting that naturally occurring canine osteosarcoma could act as a preclinical model for the human disease. Here we report the successful isolation of CSCs from primary canine osteosarcoma, as well as established cell lines. We show that these cells can form tumourspheres, and demonstrate relative resistance to chemotherapy. We demonstrate similar results for the human osteosarcma cell lines, U2OS and SAOS2. Utilizing the Affymetrix canine microarray, we are able to definitively show that there are significant differences in global gene expression profiles of isolated osteosarcoma stem cells and the daughter adherent cells. We identified 13,221 significant differences (p = 0.05, and significantly, COX-2 was expressed 141-fold more in CSC spheres than daughter adherent cells. To study the role of COX-2 expression in CSCs we utilized the COX-2 inhibitors meloxicam and mavacoxib. We found that COX-2 inhibition had no effect on CSC growth, or resistance to chemotherapy. However inhibition of COX-2 in daughter cells prevented sphere formation, indicating a potential significant role for COX-2 in tumour initiation.

COX-2 activation is associated with Akt phosphorylation and poor survival in ER-negative, HER2-positive breast cancer

International Nuclear Information System (INIS)

Glynn, Sharon A; Ambs, Stefan; Prueitt, Robyn L; Ridnour, Lisa A; Boersma, Brenda J; Dorsey, Tiffany M; Wink, David A; Goodman, Julie E; Yfantis, Harris G; Lee, Dong H

2010-01-01

Inducible cyclooxgenase-2 (COX-2) is commonly overexpressed in breast tumors and is a target for cancer therapy. Here, we studied the association of COX-2 with breast cancer survival and how this association is influenced by tumor estrogen and HER2 receptor status and Akt pathway activation. Tumor COX-2, HER2 and estrogen receptor α (ER) expression and phosphorylation of Akt, BAD, and caspase-9 were analyzed immunohistochemically in 248 cases of breast cancer. Spearman's correlation and multivariable logistic regression analyses were used to examine the relationship between COX-2 and tumor characteristics. Kaplan-Meier survival and multivariable Cox proportional hazards regression analyses were used to examine the relationship between COX-2 and disease-specific survival. COX-2 was significantly associated with breast cancer outcome in ER-negative [Hazard ratio (HR) = 2.72; 95% confidence interval (CI), 1.36-5.41; comparing high versus low COX-2] and HER2 overexpressing breast cancer (HR = 2.84; 95% CI, 1.07-7.52). However, the hazard of poor survival associated with increased COX-2 was highest among patients who were both ER-negative and HER2-positive (HR = 5.95; 95% CI, 1.01-34.9). Notably, COX-2 expression in the ER-negative and HER2-positive tumors correlated significantly with increased phosphorylation of Akt and of the two Akt targets, BAD at Ser136 and caspase-9 at Ser196. Up-regulation of COX-2 in ER-negative and HER2-positive breast tumors is associated with Akt pathway activation and is a marker of poor outcome. The findings suggest that COX-2-specific inhibitors and inhibitors of the Akt pathway may act synergistically as anticancer drugs in the ER-negative and HER2-positive breast cancer subtype

Muramyl dipeptide (MDP) induces reactive oxygen species (ROS) generation via the NOD2/COX-2/NOX4 signaling pathway in human umbilical vein endothelial cells (HUVECs).

Science.gov (United States)

Kong, Ling-Jun; Liu, Xiao-Qian; Xue, Ying; Gao, Wei; Lv, Qian-Zhou

2018-03-20

Vascular endothelium dysfunction caused by oxidative stress accelerates the pathologic process of cardiovascular diseases. NOD2, an essential receptor of innate immune system, has been demonstrated to play a critical role in atherosclerosis. Here, the aim of our study was to investigate the effect and underlying molecular mechanism of muramyl dipeptide (MDP) on NOX4-mediated ROS generation in human umbilical vein endothelial cells (HUVECs). 2,7-dichlorofluorescein diacetate staining was to measure the intracellular ROS level and showed MDP promoted ROS production in a time- and dose-dependent manner. The mRNA and protein levels of NOX4 and COX-2 were detected by real-time PCR and western blot. Small interfering RNA (siRNA) was used to silence NOD2 or COX-2 gene expression and investigate the mechanism of NOD2-mediated signaling pathway in HUVECs. Data showed that MDP induced NOX4 and COX-2 expression in a time- and dose-dependent manner. NOD2 knock-down suppressed up-regulation of COX-2 and NOX4 in HUVECs treated with MDP. Furthermore, silence of COX-2 in HUVECs down-regulated the NOX4 expression after MDP stimulation. Collectively, we indicated that NOD2 played a leading role in MDP-induced COX-2/NOX4/ROS signaling pathway in HUVECs, which was a novel regulatory mechanism in the progress of ROS generation.

Low levels of the AhR in chronic obstructive pulmonary disease (COPD)-derived lung cells increases COX-2 protein by altering mRNA stability.

Science.gov (United States)

Zago, Michela; Sheridan, Jared A; Traboulsi, Hussein; Hecht, Emelia; Zhang, Yelu; Guerrina, Necola; Matthews, Jason; Nair, Parameswaran; Eidelman, David H; Hamid, Qutayba; Baglole, Carolyn J

2017-01-01

Heightened inflammation, including expression of COX-2, is associated with chronic obstructive pulmonary disease (COPD) pathogenesis. The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that is reduced in COPD-derived lung fibroblasts. The AhR also suppresses COX-2 in response to cigarette smoke, the main risk factor for COPD, by destabilizing the Cox-2 transcript by mechanisms that may involve the regulation of microRNA (miRNA). Whether reduced AhR expression is responsible for heightened COX-2 in COPD is not known. Here, we investigated the expression of COX-2 as well as the expression of miR-146a, a miRNA known to regulate COX-2 levels, in primary lung fibroblasts derived from non-smokers (Normal) and smokers (At Risk) with and without COPD. To confirm the involvement of the AhR, AhR knock-down via siRNA in Normal lung fibroblasts and MLE-12 cells was employed as were A549-AhRko cells. Basal expression of COX-2 protein was higher in COPD lung fibroblasts compared to Normal or Smoker fibroblasts but there was no difference in Cox-2 mRNA. Knockdown of AhR in lung structural cells increased COX-2 protein by stabilizing the Cox-2 transcript. There was less induction of miR-146a in COPD-derived lung fibroblasts but this was not due to the AhR. Instead, we found that RelB, an NF-κB protein, was required for transcriptional induction of both Cox-2 and miR-146a. Therefore, we conclude that the AhR controls COX-2 protein via mRNA stability by a mechanism independent of miR-146a. Low levels of the AhR may therefore contribute to the heightened inflammation common in COPD patients.

COX-2 and PPARγ expression are potential markers of recurrence risk in mammary duct carcinoma in-situ

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Wiley Elizabeth L

2008-01-01

Full Text Available Abstract Background In women with duct carcinoma in-situ (DCIS receiving breast conservation therapy (BCT, in-breast recurrences are seen in approximately 10%, but cannot be accurately predicted using clinical and histological criteria. We performed a case-control study to identify protein markers of local recurrence risk in DCIS. Methods Women treated for DCIS with BCT, who later developed in-breast recurrence (cases were matched by age and year of treatment to women who remained free of recurrence (controls. Results A total of 69 women were included in the study, 31 cases and 38 controls. Immunohistochemical evaluation of DCIS tissue arrays was performed for estrogen receptor, progesterone receptor, HER-2/neu, cyclin D1, p53, p21, cycloxygenase-2 (COX-2 and peroxisome proliferator activated receptor γ (PPARγ. Two markers were significantly different between cases and controls on univariate analysis: strong COX-2 expression was associated with increased risk of recurrence, with 67% vs. 24% positivity in cases and controls p = 0.006; and nuclear expression of PPARγ was associated with protection from recurrence with 4% vs. 27% positivity in cases and controls, p = 0.024. In a multivariate model which included size, grade, COX-2 and PPARγ positivity, we found COX-2 positivity to be a strong independent risk factor for recurrence (OR 7.90, 95% CI 1.72–36.23., whereas size and grade were of borderline significance. PPARγ expression continued to demonstrate a protective trend, (OR 0.14, 95% CI 0.06–1.84. Conclusion Our findings suggest that COX-2 and PPARγ should be investigated further as biologic markers to predict DCIS recurrence, particularly since they are also potential therapeutic targets.

COX-1 vs. COX-2 as a determinant of basal tone in the internal anal sphincter.

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de Godoy, Márcio A F; Rattan, Neeru; Rattan, Satish

2009-02-01

Prostanoids, produced endogenously via cyclooxygenases (COXs), have been implicated in the sustained contraction of different smooth muscles. The two major types of COXs are COX-1 and COX-2. The COX subtype involved in the basal state of the internal anal sphincter (IAS) smooth muscle tone is not known. To identify the COX subtype, we examined the effect of COX-1- and COX-2-selective inhibitors, SC-560 and rofecoxib, respectively, on basal tone in the rat IAS. We also determined the effect of selective deletion of COX-1 and COX-2 genes (COX-1(-/-) and COX-2(-/-) mice) on basal tone in murine IAS. Our data show that SC-560 causes significantly more efficacious and potent concentration-dependent decreases in IAS tone than rofecoxib. In support of these data, significantly higher levels of COX-1 than COX-2 mRNA were found in the IAS. In addition, higher levels of COX-1 mRNA and protein were expressed in rat IAS than rectal smooth muscle. In wild-type mice, IAS tone was decreased 41.4 +/- 3.4% (mean +/- SE) by SC-560 (1 x 10(-5) M) and 5.4 +/- 2.2% by rofecoxib (P IAS from wild-type mice and significantly less (0.080 +/- 0.015 mN/mg) in the IAS from COX-1(-/-) mice (P IAS tone.

Increased COX-2 expression in epithelial and stromal cells of high mammographic density tissues and in a xenograft model of mammographic density.

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Chew, G L; Huo, C W; Huang, D; Hill, P; Cawson, J; Frazer, H; Hopper, J L; Haviv, I; Henderson, M A; Britt, K; Thompson, E W

2015-08-01

Mammographic density (MD) adjusted for age and body mass index is one of the strongest known risk factors for breast cancer. Given the high attributable risk of MD for breast cancer, chemoprevention with a safe and available agent that reduces MD and breast cancer risk would be beneficial. Cox-2 has been implicated in MD-related breast cancer risk, and was increased in stromal cells in high MD tissues in one study. Our study assessed differential Cox-2 expression in epithelial and stromal cells in paired samples of high and low MD human breast tissue, and in a validated xenograft biochamber model of MD. We also examined the effects of endocrine treatment upon Cox-2 expression in high and low MD tissues in the MD xenograft model. Paired high and low MD human breast tissue samples were immunostained for Cox-2, then assessed for differential expression and staining intensity in epithelial and stromal cells. High and low MD human breast tissues were separately maintained in biochambers in mice treated with Tamoxifen, oestrogen or placebo implants, then assessed for percentage Cox-2 staining in epithelial and stromal cells. Percentage Cox-2 staining was greater for both epithelial (p = 0.01) and stromal cells (p tissues. In high MD biochamber tissues, percentage Cox-2 staining was greater in stromal cells of oestrogen-treated versus placebo-treated tissues (p = 0.05).

Deoxycholate induces COX-2 expression via Erk1/2-, p38-MAPK and AP-1-dependent mechanisms in esophageal cancer cells

International Nuclear Information System (INIS)

Looby, Eileen; Abdel-Latif, Mohamed MM; Athié-Morales, Veronica; Duggan, Shane; Long, Aideen; Kelleher, Dermot

2009-01-01

The progression from Barrett's metaplasia to adenocarcinoma is associated with the acquirement of an apoptosis-resistant phenotype. The bile acid deoxycholate (DCA) has been proposed to play an important role in the development of esophageal adenocarcinoma, but the precise molecular mechanisms remain undefined. The aim of this study was to investigate DCA-stimulated COX-2 signaling pathways and their possible contribution to deregulated cell survival and apoptosis in esophageal adenocarcinoma cells. Following exposure of SKGT-4 cells to DCA, protein levels of COX-2, MAPK and PARP were examined by immunoblotting. AP-1 activity was assessed by mobility shift assay. DCA-induced toxicity was assessed by DNA fragmentation and MTT assay. DCA induced persistent activation of the AP-1 transcription factor with Fra-1 and JunB identified as the predominant components of the DCA-induced AP-1 complex. DCA activated Fra-1 via the Erk1/2- and p38 MAPK while Erk1/2 is upstream of JunB. Moreover, DCA stimulation mediated inhibition of proliferation with concomitant low levels of caspase-3-dependent PARP cleavage and DNA fragmentation. Induction of the anti-apoptotic protein COX-2 by DCA, via MAPK/AP-1 pathway appeared to balance the DCA mediated activation of pro-apoptotic markers such as PARP cleavage and DNA fragmentation. Both of these markers were increased upon COX-2 suppression by aspirin pretreatment prior to DCA exposure. DCA regulates both apoptosis and COX-2-regulated cell survival in esophageal cells suggesting that the balance between these two opposing signals may determine the transformation potential of DCA as a component of the refluxate

Deoxycholate induces COX-2 expression via Erk1/2-, p38-MAPK and AP-1-dependent mechanisms in esophageal cancer cells.

LENUS (Irish Health Repository)

Looby, Eileen

2009-01-01

BACKGROUND: The progression from Barrett\\'s metaplasia to adenocarcinoma is associated with the acquirement of an apoptosis-resistant phenotype. The bile acid deoxycholate (DCA) has been proposed to play an important role in the development of esophageal adenocarcinoma, but the precise molecular mechanisms remain undefined. The aim of this study was to investigate DCA-stimulated COX-2 signaling pathways and their possible contribution to deregulated cell survival and apoptosis in esophageal adenocarcinoma cells. METHODS: Following exposure of SKGT-4 cells to DCA, protein levels of COX-2, MAPK and PARP were examined by immunoblotting. AP-1 activity was assessed by mobility shift assay. DCA-induced toxicity was assessed by DNA fragmentation and MTT assay. RESULTS: DCA induced persistent activation of the AP-1 transcription factor with Fra-1 and JunB identified as the predominant components of the DCA-induced AP-1 complex. DCA activated Fra-1 via the Erk1\\/2- and p38 MAPK while Erk1\\/2 is upstream of JunB. Moreover, DCA stimulation mediated inhibition of proliferation with concomitant low levels of caspase-3-dependent PARP cleavage and DNA fragmentation. Induction of the anti-apoptotic protein COX-2 by DCA, via MAPK\\/AP-1 pathway appeared to balance the DCA mediated activation of pro-apoptotic markers such as PARP cleavage and DNA fragmentation. Both of these markers were increased upon COX-2 suppression by aspirin pretreatment prior to DCA exposure. CONCLUSION: DCA regulates both apoptosis and COX-2-regulated cell survival in esophageal cells suggesting that the balance between these two opposing signals may determine the transformation potential of DCA as a component of the refluxate.

Deoxycholate induces COX-2 expression via Erk1/2-, p38-MAPK and AP-1-dependent mechanisms in esophageal cancer cells

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Long Aideen

2009-06-01

Full Text Available Abstract Background The progression from Barrett's metaplasia to adenocarcinoma is associated with the acquirement of an apoptosis-resistant phenotype. The bile acid deoxycholate (DCA has been proposed to play an important role in the development of esophageal adenocarcinoma, but the precise molecular mechanisms remain undefined. The aim of this study was to investigate DCA-stimulated COX-2 signaling pathways and their possible contribution to deregulated cell survival and apoptosis in esophageal adenocarcinoma cells. Methods Following exposure of SKGT-4 cells to DCA, protein levels of COX-2, MAPK and PARP were examined by immunoblotting. AP-1 activity was assessed by mobility shift assay. DCA-induced toxicity was assessed by DNA fragmentation and MTT assay. Results DCA induced persistent activation of the AP-1 transcription factor with Fra-1 and JunB identified as the predominant components of the DCA-induced AP-1 complex. DCA activated Fra-1 via the Erk1/2- and p38 MAPK while Erk1/2 is upstream of JunB. Moreover, DCA stimulation mediated inhibition of proliferation with concomitant low levels of caspase-3-dependent PARP cleavage and DNA fragmentation. Induction of the anti-apoptotic protein COX-2 by DCA, via MAPK/AP-1 pathway appeared to balance the DCA mediated activation of pro-apoptotic markers such as PARP cleavage and DNA fragmentation. Both of these markers were increased upon COX-2 suppression by aspirin pretreatment prior to DCA exposure. Conclusion DCA regulates both apoptosis and COX-2-regulated cell survival in esophageal cells suggesting that the balance between these two opposing signals may determine the transformation potential of DCA as a component of the refluxate.

Effects of hypo- and hyperthyroidism on proliferation, angiogenesis, apoptosis and expression of COX-2 in the corpus luteum of female rats.

Science.gov (United States)

Silva, J F; Ocarino, N M; Vieira, A L S; Nascimento, E F; Serakides, R

2013-08-01

Although thyroid dysfunction occurs frequently in humans and some animal species, the mechanisms by which hypo- and hyperthyroidism affect the corpus luteum have not been thoroughly elucidated. This study evaluated the levels of proliferative activity, angiogenesis, apoptosis and expression of cyclooxygenase-2 in the corpus luteum of female rats with thyroid dysfunction. These processes may be important in understanding the reproductive changes caused by thyroid dysfunction. A total of 18 adult female rats were divided into three groups (control, hypothyroid and hyperthyroid) with six animals per group. Three months after treatment to induce thyroid dysfunction, the rats were euthanized in the dioestrus phase. The ovaries were collected and immunohistochemically analysed for expression of the cell proliferation marker CDC-47, vascular endothelial growth factor (VEGF), VEGF receptor Flk-1 and cyclooxygenase-2 (COX-2). Apoptosis was evaluated using the TUNEL assay. Hypothyroidism reduced the intensity and area of COX-2 expression in the corpus luteum (p hyperthyroidism did not alter COX-2 expression in the dioestrus phase. Hypothyroidism significantly reduced the expression of CDC-47 in endothelial cells and pericytes in the corpus luteum, whereas hyperthyroidism did not induce a detectable change in CDC-47 expression (p > 0.05). Hypothyroidism reduced the level of apoptosis in luteal cells (p hyperthyroidism increased the level of apoptosis in the corpus luteum (p < 0.05). In conclusion, thyroid dysfunction differentially affects the levels of proliferative activity, angiogenesis and apoptosis and COX-2 expression in the corpus luteum of female rats. © 2013 Blackwell Verlag GmbH.

Inhibitory Effects of Culinary Herbs and Spices on the Growth of HCA-7 Colorectal Cancer Cells and Their COX-2 Expression.

Science.gov (United States)

Jaksevicius, Andrius; Carew, Mark; Mistry, Calli; Modjtahedi, Helmout; Opara, Elizabeth I

2017-09-21

It is unclear if the anti-inflammatory properties of culinary herbs and spices (CHS) are linked to their ability to inhibit Colorectal cancer cell (CRC) growth. Furthermore, their therapeutic potential with regards to CRC is unknown. The aim of this study was to establish if the inhibition of HCA-7 CRC cell growth by a selection of culinary herbs and spices (CHS) is linked to the inhibition of the cells' cyclooxygenase-2 (COX-2 )expression, and to investigate their therapeutic potential. CHS inhibited the growth of Human colon adenocarcinoma-7 (HCA-7) cells; the order of potency was turmeric, bay leaf, ginger, sage, and rosemary; their combinations had a synergistic or additive effect on cell growth inhibition. CHS also inhibited COX-2 expression and activity; this action was comparable to that of the specific COX-2 inhibitor Celecoxib. Coincident with COX-2 inhibition was the accumulation of cells in the sub G1 phase of the HCA-7's cell cycle and, using bay leaf and turmeric, the cleavage of caspase 3 and poly (ADP-ribose) polymerase (PARP). This latter effect showed that the effect of these CHS on growth arrest was irreversible, and was comparable to that of the caspase activator Etoposide. This study provides evidence of a link between the inhibition of HCA-7 growth, and its COX-2 expression, by CHS, and their therapeutic potential.

Kaempferol attenuates COX-2 expression in IL-6-induced macrophages and carrageenan-induced mouse paw edema by targeting STAT3 and NF-kB

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Anandita Basu

2017-10-01

Full Text Available Dietary polyphenols are reported to possess varied pharmacological activities, viz. antioxidant, anti-inflammatory, anti-cancer, anti-allergic actions. Here, we report the efficacy of Kaempferol (kae to attenuate expression of IL-6 induced cycloxygenase-2 (COX-2, an inducible isoform of cycloxygenase enzyme family that catalyzes synthesis of inflammatory mediators, prostanoids and prostaglandins. IL-6 is a pleiotropic cytokine involved in both acute and chronic inflammation. Our results showed that kae attenuated COX-2 expression at both mRNA and protein level in IL-6-induced THP1 macrophages. This attenuation of COX-2 expression by kae involved dose-dependent inhibition of phosphorylation of STAT3 (Tyr 705 and NF-kB p65 (Ser 536 leading to their deactivation and reduced nuclear localization in THP-1 macrophages. Moreover, kae modulates COX-2 expression as well as STAT3 and NF-kB activation in carrageenan-induced mouse paw edema model. RT-PCR and western blot analysis from paw tissues were harvested after kae injection (i.p followed by carrageenan-treatment in sub-plantar region of right hind paw. Results showed that kae attenuated COX-2 expression and STAT3 and NF-kB activation in carrageenan-induced mouse paw edema, suggesting that inhibition of both IL-6-STAT3-COX-2 and IL-6-NFkB-COX-2 axes by kae might be stimulus-independent. To understand binding affinity of kae with NF-kB and STAT3, docking analysis was performed using Patchdock server. From our findings, we observed strong binding affinity and transient interaction in both NF-kB/kae and STAT3/kae complexes. We noticed negative atomic contact energy and greater interface area for both the complexes. Selected complexes obtained from Patchdock were refined using Firedock online server which also suggested similar negative binding energy profile. It is plausible that kae attenuates COX-2 expression by directly binding to both STAT3 and NF-kB proteins and inhibiting their activation and

Maximal COX-2 and ppRb expression in neurons occurs during early Braak stages prior to the maximal activation of astrocytes and microglia in Alzheimer's disease

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Arendt Thomas

2005-11-01

Full Text Available Abstract Neuronal expression of cyclooxygenase-2 (COX-2 and cell cycle proteins is suggested to contribute to neurodegeneration during Alzheimer's disease (AD. The stimulus that induces COX-2 and cell cycle protein expression in AD is still elusive. Activated glia cells are shown to secrete substances that can induce expression of COX-2 and cell cycle proteins in vitro. Using post mortem brain tissue we have investigated whether activation of microglia and astrocytes in AD brain can be correlated with the expression of COX-2 and phosphorylated retinoblastoma protein (ppRb. The highest levels of neuronal COX-2 and ppRb immunoreactivity are observed in the first stages of AD pathology (Braak 0–II, Braak A. No significant difference in COX-2 or ppRb neuronal immunoreactivity is observed between Braak stage 0 and later Braak stages for neurofibrillary changes or amyloid plaques. The mean number of COX-2 or ppRb immunoreactive neurons is significantly decreased in Braak stage C compared to Braak stage A for amyloid deposits. Immunoreactivity for glial markers KP1, CR3/43 and GFAP appears in the later Braak stages and is significantly increased in Braak stage V-VI compared to Braak stage 0 for neurofibrillary changes. In addition, a significant negative correlation is observed between the presence of KP1, CR3/43 and GFAP immunoreactivity and the presence of neuronal immunoreactivity for COX-2 and ppRb. These data show that maximal COX-2 and ppRb immunoreactivity in neurons occurs during early Braak stages prior to the maximal activation of astrocytes and microglia. In contrast to in vitro studies, post mortem data do not support a causal relation between the activation of microglia and astrocytes and the expression of neuronal COX-2 and ppRb in the pathological cascade of AD.

Dietary blue pigments derived from genipin, attenuate inflammation by inhibiting LPS-induced iNOS and COX-2 expression via the NF-κB inactivation.

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Wang, Qiang-Song; Xiang, Yaozu; Cui, Yuan-Lu; Lin, Ke-Ming; Zhang, Xin-Fang

2012-01-01

The edible blue pigments produced by gardenia fruits have been used as value-added colorants for foods in East Asia for 20 years. However, the biological activity of the blue pigments derived from genipin has not been reported. The anti-inflammatory effect of blue pigments was studied in lipopolysaccharide (LPS) stimulated RAW 264.7 macrophage in vitro. The secretions of nitric oxide (NO) and prostaglandin E(2) (PGE(2)) were inhibited in concentration-dependent manner by blue pigments. Real-time reverse-transcription polymerase chain reaction (Real-time RT-PCR) analyses demonstrated that the mRNA expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), interleukin (IL)-6, and tumor necrosis factor alpha (TNF-α) was inhibited, moreover, ELISA results showed that the productions of IL-6 and TNF-α were inhibited. Cell-based ELISA revealed the COX-2 protein expression was inhibited. The proteome profiler array showed that 12 cytokines and chemokines involved in the inflammatory process were down-regulated by blue pigments. Blue pigments inhibited the nuclear transcription factor kappa-B (NF-κB) activation induced by LPS, and this was associated with decreasing the DNA-binding activity of p65 and p50. Furthermore, blue pigments suppressed the degradation of inhibitor of κB (IκB) α, Inhibitor of NF-κB Kinase (IKK) α, IKK-β, and phosphorylation of IκB-α. The anti-inflammatory effect of blue pigments in vivo was studied in carrageenan-induced paw edema and LPS-injecting ICR mice. Finally, blue pigments significantly inhibited paw swelling and reduced plasma TNF-α and IL-6 production in vivo. These results suggest that the anti-inflammatory properties of blue pigments might be the results from the inhibition of iNOS, COX-2, IL-6, IL-1β, and TNF-α expression through the down-regulation of NF-κB activation, which will provide strong scientific evidence for the edible blue pigments to be developed as a new health-enhancing nutritional food

Dietary blue pigments derived from genipin, attenuate inflammation by inhibiting LPS-induced iNOS and COX-2 expression via the NF-κB inactivation.

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Qiang-Song Wang

Full Text Available The edible blue pigments produced by gardenia fruits have been used as value-added colorants for foods in East Asia for 20 years. However, the biological activity of the blue pigments derived from genipin has not been reported.The anti-inflammatory effect of blue pigments was studied in lipopolysaccharide (LPS stimulated RAW 264.7 macrophage in vitro. The secretions of nitric oxide (NO and prostaglandin E(2 (PGE(2 were inhibited in concentration-dependent manner by blue pigments. Real-time reverse-transcription polymerase chain reaction (Real-time RT-PCR analyses demonstrated that the mRNA expression of inducible nitric oxide synthase (iNOS, cyclooxygenase-2 (COX-2, interleukin (IL-6, and tumor necrosis factor alpha (TNF-α was inhibited, moreover, ELISA results showed that the productions of IL-6 and TNF-α were inhibited. Cell-based ELISA revealed the COX-2 protein expression was inhibited. The proteome profiler array showed that 12 cytokines and chemokines involved in the inflammatory process were down-regulated by blue pigments. Blue pigments inhibited the nuclear transcription factor kappa-B (NF-κB activation induced by LPS, and this was associated with decreasing the DNA-binding activity of p65 and p50. Furthermore, blue pigments suppressed the degradation of inhibitor of κB (IκB α, Inhibitor of NF-κB Kinase (IKK α, IKK-β, and phosphorylation of IκB-α. The anti-inflammatory effect of blue pigments in vivo was studied in carrageenan-induced paw edema and LPS-injecting ICR mice. Finally, blue pigments significantly inhibited paw swelling and reduced plasma TNF-α and IL-6 production in vivo.These results suggest that the anti-inflammatory properties of blue pigments might be the results from the inhibition of iNOS, COX-2, IL-6, IL-1β, and TNF-α expression through the down-regulation of NF-κB activation, which will provide strong scientific evidence for the edible blue pigments to be developed as a new health-enhancing nutritional

Expression of COX-2, CD44v6 and CD147 and relationship with invasion and lymph node metastasis in hypopharyngeal squamous cell carcinoma.

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Qing Yang

Full Text Available To assess the expression of COX-2,CD44v6 and CD147 in hypopharyngeal squamous cell carcinomas and the three biomarkers correlation with tumor invasion and lymph node metastasis of Chinese people. 101 cases of surgically excised primary tumor were included in this study, and 40 tissues of epithelium adjacent to carcinoma were used as controls. We characterized the immunohistochemical expression of COX-2, CD44v6, and CD147 in 141 formalin-fixed, paraffin-embedded tissues, and measured the mean optical density (OD of the positive area to identify the expression of the three bio-markers and relationship with tumor invasion and lymph node metastasis. Our study demonstrates that the expression of the COX-2 and CD147 were significantly increased in carcinoma tissues compared to the epithelium adjacent to carcinoma. We also observed that the expression of COX-2, CD44v6, and CD147 were significantly associated with T classification, lymph node metastasis and clinical stage. There was strong significant correlation among the three biomarkers as well. Additionally, we indicated that recurrence and ≥ P50 level of COX-2 expression had an independent prognostic effect on prognosis. In conclusion, the three biomarkers play important roles in tumor invasion and lymph node metastases and might be valuable indicators of tumor metastasis in hypopharyngeal squamous cell carcinoma.

Ahr2-dependence of PCB126 effects on the swim bladder in relation to expression of CYP1 and cox-2 genes in developing zebrafish

International Nuclear Information System (INIS)

Jönsson, Maria E.; Kubota, Akira; Timme-Laragy, Alicia R.; Woodin, Bruce; Stegeman, John J.

2012-01-01

The teleost swim bladder is assumed a homolog of the tetrapod lung. Both swim bladder and lung are developmental targets of persistent aryl hydrocarbon receptor (AHR) agonists; in zebrafish (Danio rerio) the swim bladder fails to inflate with exposure to 3,3′,4,4′,5-pentachlorobiphenyl (PCB126). The mechanism for this effect is unknown, but studies have suggested roles of cytochrome P450 1 (CYP1) and cyclooxygenase 2 (Cox-2) in some Ahr-mediated developmental effects in zebrafish. We determined relationships between swim bladder inflation and CYP1 and Cox-2 mRNA expression in PCB126-exposed zebrafish embryos. We also examined effects on β-catenin dependent transcription, histological effects, and Ahr2 dependence of the effect of PCB126 on swim bladder using morpholinos targeting ahr2. One-day-old embryos were exposed to waterborne PCB126 or carrier (DMSO) for 24 h and then held in clean water until day 4, a normal time for swim bladder inflation. The effects of PCB126 were concentration-dependent with EC 50 values of 1.4 to 2.0 nM for induction of the CYP1s, 3.7 and 5.1 nM (or higher) for cox-2a and cox-2b induction, and 2.5 nM for inhibition of swim bladder inflation. Histological defects included a compaction of the developing bladder. Ahr2-morpholino treatment rescued the effect of PCB126 (5 nM) on swim bladder inflation and blocked induction of CYP1A, cox-2a, and cox-2b. With 2 nM PCB126 approximately 30% of eleutheroembryos failed to inflate the swim bladder, but there was no difference in CYP1 or cox-2 mRNA expression between those embryos and embryos showing inflated swim bladder. Our results indicate that PCB126 blocks swim bladder inflation via an Ahr2-mediated mechanism. This mechanism seems independent of CYP1 or cox-2 mRNA induction but may involve abnormal development of swim bladder cells. -- Highlights: ► PCB126 caused cellular changes in the developing swim bladder. ► Swim bladder inflation was not related to expression of CYP1 or cox-2. �

Ahr2-dependence of PCB126 effects on the swim bladder in relation to expression of CYP1 and cox-2 genes in developing zebrafish

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Jönsson, Maria E., E-mail: maria.jonsson@ebc.uu.se [Dept. of Environmental Toxicology, Evolutionary Biology, Centre, Uppsala University, Norbyvägen 18A, 752 36 Uppsala (Sweden); Biology Department, Redfield 3-42 MS 32, Woods Hole Oceanographic Institution, Woods Hole, MA, 02543 (United States); Kubota, Akira, E-mail: akubota@whoi.edu [Biology Department, Redfield 3-42 MS 32, Woods Hole Oceanographic Institution, Woods Hole, MA, 02543 (United States); Timme-Laragy, Alicia R., E-mail: atimmelaragy@whoi.edu [Biology Department, Redfield 3-42 MS 32, Woods Hole Oceanographic Institution, Woods Hole, MA, 02543 (United States); Division of Environmental Health, Department of Public Health, School of Public Health and Health Sciences, University of Massachusetts, Amherst, MA, 01003 (United States); Woodin, Bruce, E-mail: bwoodin@whoi.edu [Biology Department, Redfield 3-42 MS 32, Woods Hole Oceanographic Institution, Woods Hole, MA, 02543 (United States); Stegeman, John J., E-mail: jstegeman@whoi.edu [Biology Department, Redfield 3-42 MS 32, Woods Hole Oceanographic Institution, Woods Hole, MA, 02543 (United States)

2012-12-01

The teleost swim bladder is assumed a homolog of the tetrapod lung. Both swim bladder and lung are developmental targets of persistent aryl hydrocarbon receptor (AHR) agonists; in zebrafish (Danio rerio) the swim bladder fails to inflate with exposure to 3,3′,4,4′,5-pentachlorobiphenyl (PCB126). The mechanism for this effect is unknown, but studies have suggested roles of cytochrome P450 1 (CYP1) and cyclooxygenase 2 (Cox-2) in some Ahr-mediated developmental effects in zebrafish. We determined relationships between swim bladder inflation and CYP1 and Cox-2 mRNA expression in PCB126-exposed zebrafish embryos. We also examined effects on β-catenin dependent transcription, histological effects, and Ahr2 dependence of the effect of PCB126 on swim bladder using morpholinos targeting ahr2. One-day-old embryos were exposed to waterborne PCB126 or carrier (DMSO) for 24 h and then held in clean water until day 4, a normal time for swim bladder inflation. The effects of PCB126 were concentration-dependent with EC{sub 50} values of 1.4 to 2.0 nM for induction of the CYP1s, 3.7 and 5.1 nM (or higher) for cox-2a and cox-2b induction, and 2.5 nM for inhibition of swim bladder inflation. Histological defects included a compaction of the developing bladder. Ahr2-morpholino treatment rescued the effect of PCB126 (5 nM) on swim bladder inflation and blocked induction of CYP1A, cox-2a, and cox-2b. With 2 nM PCB126 approximately 30% of eleutheroembryos failed to inflate the swim bladder, but there was no difference in CYP1 or cox-2 mRNA expression between those embryos and embryos showing inflated swim bladder. Our results indicate that PCB126 blocks swim bladder inflation via an Ahr2-mediated mechanism. This mechanism seems independent of CYP1 or cox-2 mRNA induction but may involve abnormal development of swim bladder cells. -- Highlights: ► PCB126 caused cellular changes in the developing swim bladder. ► Swim bladder inflation was not related to expression of CYP1 or cox

Ahr2-dependance of PCB126 effects on the swimbladder in relation to expression of CYP1 and cox-2 genes in developing zebrafish

Science.gov (United States)

Jönsson, Maria E.; Kubota, Akira; Timme-Laragy, Alicia; Woodin, Bruce; Stegeman, John J.

2012-01-01

The teleost swimbladder is assumed a homolog of the tetrapod lung. Both swimbladder and lung are developmental targets of persistent aryl hydrocarbon receptor (AHR1) agonists; in zebrafish (Danio rerio) the swimbladder fails to inflate with exposure to 3,3’,4,4’,5-pentachlorobiphenyl (PCB126). The mechanism for this effect is unknown, but studies have suggested roles of cytochrome P4501 (CYP1) and cyclooxygenase 2 (Cox-2) in some Ahr-mediated developmental effects in zebrafish. We determined relationships between swimbladder inflation and CYP1 and Cox-2 mRNA expression in PCB126-exposed zebrafish embryos. We also examined effects on β-catenin dependent transcription, histological effects, and Ahr2 dependance of the effect of PCB126 on swimbladder using morpholinos targeting ahr2. One-day-old embryos were exposed to waterborne PCB126 or carrier (DMSO) for 24 h and then held in clean water until day 4, a normal time for swimbladder inflation. The effects of PCB126 were concentration-dependent with EC50 values of 1.4 to 2.0 nM for induction of the CYP1s, 3.7 and 5.1 nM (or higher) for cox-2a and cox-2b induction, and 2.5 nM for inhibition of swimbladder inflation. Histological defects included a compaction of the developing bladder. Ahr2-morpholino treatment rescued the effect of PCB126 (5 nM) on swimbladder inflation and blocked induction of CYP1A, cox-2a, and cox-2b. With 2 nM PCB126 approximately 30% of eleutheroembryos2 failed to inflate the swimbladder, but there was no difference in CYP1 or cox-2 mRNA expression between those embryos and embryos showing inflated swimbladder. Our results indicate that PCB126 blocks swimbladder inflation via an Ahr2-mediated mechanism. This mechanism seems independent of CYP1 or cox-2 mRNA induction but may involve abnormal development of swimbladder cells. PMID:23036320

Induction of HO-1 by carbon monoxide releasing molecule-2 attenuates thrombin-induced COX-2 expression and hypertrophy in primary human cardiomyocytes

International Nuclear Information System (INIS)

Chien, Peter Tzu-Yu; Lin, Chih-Chung; Hsiao, Li-Der; Yang, Chuen-Mao

2015-01-01

Carbon monoxide (CO) is one of the cytoprotective byproducts of heme oxygenase (HO)-1 and exerts anti-inflammatory action in various models. However, the detailed mechanisms underlying CO-induced HO-1 expression in primary human cardiomyocytes remain largely unidentified. We used primary left ventricle myocytes as a model and applied CO releasing molecule (CORM)-2 to investigate the relationship of CO and HO-1 expression. We herein used Western blot, real-time PCR, promoter activity and EIA to investigate the role of HO-1 expression protecting against thrombin-mediated responses. We found that thrombin-induced COX-2 expression, PGE 2 release and cardiomyocyte hypertrophy markers (increase in ANF/BNP, α-actin expression and cell surface area) was attenuated by pretreatment with CORM-2 which was partially reversed by hemoglobin (Hb) or ZnPP (an inhibitor of HO-1 activity), suggesting that HO-1/CO system may be of clinical importance to ameliorate heart failure through inhibition of inflammatory responses. CORM-2-induced HO-1 protein expression, mRNA and promoter was attenuated by pretreatment with the inhibitors of Pyk2 (PF431396), PDGFR (AG1296), PI3K (LY294002), Akt (SH-5), p38 (SB202530), JNK1/2 (SP600125), FoxO1 (AS1842856) and Sp1 (mithramycin A). The involvement of these signaling components was further confirmed by transfection with respective siRNAs, consistent with those of pharmacological inhibitors. These results suggested that CORM-2-induced HO-1 expression is mediated through a Pyk2/PDGFR/PI3K/Akt/FoxO1/Sp1-dependent manner and exerts a cytoprotective effect in human cardiomyocytes. - Graphical abstract: In summary, CORM-2 treatment induces Pyk2 transactivated PDGFR, which induces PI3K/Akt/MAPK activation, and then recruits Sp1/Foxo1 transcriptional factors to regulate HO-1 gene expression in primary human cardiomyocytes. - Highlights: • CORM-2 induces HO-1 expression. • Pyk2-dependent PDGFR activates PI3K/Akt/MAPK pathway in CORM-2-induced HO-1

Induction of HO-1 by carbon monoxide releasing molecule-2 attenuates thrombin-induced COX-2 expression and hypertrophy in primary human cardiomyocytes

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Chien, Peter Tzu-Yu [Department of Physiology and Pharmacology and Health Ageing Research Center, Chang Gung University, Kwei-Shan, Tao-Yuan, Taiwan (China); Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Kwei-Shan, Tao-Yuan, Taiwan (China); Lin, Chih-Chung; Hsiao, Li-Der [Department of Anesthetics, Chang Gung Memorial Hospital at Lin-Kou and College of Medicine, Chang Gung University, Kwei-San, Tao-Yuan, Taiwan (China); Yang, Chuen-Mao, E-mail: chuenmao@mail.cgu.edu.tw [Department of Physiology and Pharmacology and Health Ageing Research Center, Chang Gung University, Kwei-Shan, Tao-Yuan, Taiwan (China); Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Kwei-Shan, Tao-Yuan, Taiwan (China); Research Center for Industry of Human Ecology and Graduate Institute of Health Industry Technology, Chang Gung University of Science and Technology, Tao-Yuan, Taiwan (China)

2015-12-01

Carbon monoxide (CO) is one of the cytoprotective byproducts of heme oxygenase (HO)-1 and exerts anti-inflammatory action in various models. However, the detailed mechanisms underlying CO-induced HO-1 expression in primary human cardiomyocytes remain largely unidentified. We used primary left ventricle myocytes as a model and applied CO releasing molecule (CORM)-2 to investigate the relationship of CO and HO-1 expression. We herein used Western blot, real-time PCR, promoter activity and EIA to investigate the role of HO-1 expression protecting against thrombin-mediated responses. We found that thrombin-induced COX-2 expression, PGE{sub 2} release and cardiomyocyte hypertrophy markers (increase in ANF/BNP, α-actin expression and cell surface area) was attenuated by pretreatment with CORM-2 which was partially reversed by hemoglobin (Hb) or ZnPP (an inhibitor of HO-1 activity), suggesting that HO-1/CO system may be of clinical importance to ameliorate heart failure through inhibition of inflammatory responses. CORM-2-induced HO-1 protein expression, mRNA and promoter was attenuated by pretreatment with the inhibitors of Pyk2 (PF431396), PDGFR (AG1296), PI3K (LY294002), Akt (SH-5), p38 (SB202530), JNK1/2 (SP600125), FoxO1 (AS1842856) and Sp1 (mithramycin A). The involvement of these signaling components was further confirmed by transfection with respective siRNAs, consistent with those of pharmacological inhibitors. These results suggested that CORM-2-induced HO-1 expression is mediated through a Pyk2/PDGFR/PI3K/Akt/FoxO1/Sp1-dependent manner and exerts a cytoprotective effect in human cardiomyocytes. - Graphical abstract: In summary, CORM-2 treatment induces Pyk2 transactivated PDGFR, which induces PI3K/Akt/MAPK activation, and then recruits Sp1/Foxo1 transcriptional factors to regulate HO-1 gene expression in primary human cardiomyocytes. - Highlights: • CORM-2 induces HO-1 expression. • Pyk2-dependent PDGFR activates PI3K/Akt/MAPK pathway in CORM-2-induced HO

Indomethacin treatment prior to pentylenetetrazole-induced seizures downregulates the expression of il1b and cox2 and decreases seizure-like behavior in zebrafish larvae.

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Barbalho, Patrícia Gonçalves; Lopes-Cendes, Iscia; Maurer-Morelli, Claudia Vianna

2016-03-09

It has been demonstrated that the zebrafish model of pentylenetetrazole (PTZ)-evoked seizures and the well-established rodent models of epilepsy are similar pertaining to behavior, electrographic features, and c-fos expression. Although this zebrafish model is suitable for studying seizures, to date, inflammatory response after seizures has not been investigated using this model. Because a relationship between epilepsy and inflammation has been established, in the present study we investigated the transcript levels of the proinflammatory cytokines interleukin-1 beta (il1b) and cyclooxygenase-2 (cox2a and cox2b) after PTZ-induced seizures in the brain of zebrafish 7 days post fertilization. Furthermore, we exposed the fish to the nonsteroidal anti-inflammatory drug indomethacin prior to PTZ, and we measured its effect on seizure latency, number of seizure behaviors, and mRNA expression of il1b, cox2b, and c-fos. We used quantitative real-time PCR to assess the mRNA expression of il1b, cox2a, cox2b, and c-fos, and visual inspection was used to monitor seizure latency and the number of seizure-like behaviors. We found a short-term upregulation of il1b, and we revealed that cox2b, but not cox2a, was induced after seizures. Indomethacin treatment prior to PTZ-induced seizures downregulated the mRNA expression of il1b, cox2b, and c-fos. Moreover, we observed that in larvae exposed to indomethacin, seizure latency increased and the number of seizure-like behaviors decreased. This is the first study showing that il1b and cox-2 transcripts are upregulated following PTZ-induced seizures in zebrafish. In addition, we demonstrated the anticonvulsant effect of indomethacin based on (1) the inhibition of PTZ-induced c-fos transcription, (2) increase in seizure latency, and (3) decrease in the number of seizure-like behaviors. Furthermore, anti-inflammatory effect of indomethacin is clearly demonstrated by the downregulation of the mRNA expression of il1b and cox2b. Our results

Nucleobindin co-localizes and associates with cyclooxygenase (COX-2 in human neutrophils.

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Patrick Leclerc

2008-05-01

Full Text Available The inducible cyclooxygenase isoform (COX-2 is associated with inflammation, tumorigenesis, as well as with physiological events. Despite efforts deployed in order to understand the biology of this multi-faceted enzyme, much remains to be understood. Nucleobindin (Nuc, a ubiquitous Ca(2+-binding protein, possesses a putative COX-binding domain. In this study, we investigated its expression and subcellular localization in human neutrophils, its affinity for COX-2 as well as its possible impact on PGE(2 biosynthesis. Complementary subcellular localization approaches including nitrogen cavitation coupled to Percoll fractionation, immunofluorescence, confocal and electron microscopy collectively placed Nuc, COX-2, and all of the main enzymes involved in prostanoid synthesis, in the Golgi apparatus and endoplasmic reticulum of human neutrophils. Immunoprecipitation experiments indicated a high affinity between Nuc and COX-2. Addition of human recombinant (hr Nuc to purified hrCOX-2 dose-dependently caused an increase in PGE(2 biosynthesis in response to arachidonic acid. Co-incubation of Nuc with COX-2-expressing neutrophil lysates also increased their capacity to produce PGE(2. Moreover, neutrophil transfection with hrNuc specifically enhanced PGE(2 biosynthesis. Together, these results identify a COX-2-associated protein which may have an impact in prostanoid biosynthesis.

Cox-2 inhibitors and the risk of cardiovascular thrombotic events.

LENUS (Irish Health Repository)

Khan, M

2012-04-01

In 1971, Vane showed that the analgesic action of traditional NSAIDs relies on inhibition of the cyclo-oxygenase (COX) enzyme, which in turn results in reduced synthesis of proalgesic prostaglandins. Two decades later COX was shown to exist as two distinct isoforms. The constitutive isoform COX-1, supports the beneficial homeostatic functions whereas the inducible isoform, COX-2 becomes up regulated by inflammatory mediators and its products cause many of the symptoms of inflammatory diseases such as rheumatoid and osteoarthritis. Despite the benefits of NSAIDs for acute and chronic pain one of the most clinically significant and well characterized adverse effect is on GI mucosa. The search for NSAIDs with less gastrointestinal toxicity led to the introduction of the selective cyclo-oxygenase-2 (COX-2) inhibitors. The COX-2 selective (COX-1 sparing) inhibitors are associated with reduced GI mucosal damage as demonstrated in several trials. In light of the overwhelming and sometimes contradictory information for patients and physicians regarding the safety of COX-2 agents this article will summarize the available evidence regarding cardiovascular (CV) safety data and contemporary recommendations for prescribing of COX-2-selective NSAIDs.

Sodium Channel Voltage-Gated Beta 2 Plays a Vital Role in Brain Aging Associated with Synaptic Plasticity and Expression of COX5A and FGF-2.

Science.gov (United States)

XiYang, Yan-Bin; Wang, You-Cui; Zhao, Ya; Ru, Jin; Lu, Bing-Tuan; Zhang, Yue-Ning; Wang, Nai-Chao; Hu, Wei-Yan; Liu, Jia; Yang, Jin-Wei; Wang, Zhao-Jun; Hao, Chun-Guang; Feng, Zhong-Tang; Xiao, Zhi-Cheng; Dong, Wei; Quan, Xiong-Zhi; Zhang, Lian-Feng; Wang, Ting-Hua

2016-03-01

The role of sodium channel voltage-gated beta 2 (SCN2B) in brain aging is largely unknown. The present study was therefore designed to determine the role of SCN2B in brain aging by using the senescence-accelerated mice prone 8 (SAMP8), a brain senescence-accelerated animal model, together with the SCN2B transgenic mice. The results showed that SAMP8 exhibited impaired learning and memory functions, assessed by the Morris water maze test, as early as 8 months of age. The messenger RNA (mRNA) and protein expressions of SCN2B were also upregulated in the prefrontal cortex at this age. Treatment with traditional Chinese anti-aging medicine Xueshuangtong (Panax notoginseng saponins, PNS) significantly reversed the SCN2B expressions in the prefrontal cortex, resulting in improved learning and memory. Moreover, SCN2B knockdown transgenic mice were generated and bred to determine the roles of SCN2B in brain senescence. A reduction in the SCN2B level by 60.68% resulted in improvement in the hippocampus-dependent spatial recognition memory and long-term potential (LTP) slope of field excitatory postsynaptic potential (fEPSP), followed by an upregulation of COX5A mRNA levels and downregulation of fibroblast growth factor-2 (FGF-2) mRNA expression. Together, the present findings indicated that SCN2B could play an important role in the aging-related cognitive deterioration, which is associated with the regulations of COX5A and FGF-2. These findings could provide the potential strategy of candidate target to develop antisenescence drugs for the treatment of brain aging.

Hormophysa triquerta polyphenol, an elixir that deters CXCR4- and COX2-dependent dissemination destiny of treatment-resistant pancreatic cancer cells.

Science.gov (United States)

Aravindan, Sheeja; Ramraj, Satishkumar; Kandasamy, Kathiresan; Thirugnanasambandan, Somasundaram S; Somasundaram, Dinesh Babu; Herman, Terence S; Aravindan, Natarajan

2017-01-24

Therapy-resistant pancreatic cancer (PC) cells play a crucial role in tumor relapse, recurrence, and metastasis. Recently, we showed the anti-PC potential of an array of seaweed polyphenols and identified efficient drug deliverables. Herein, we investigated the benefit of one such deliverable, Hormophysa triquerta polyphenol (HT-EA), in regulating the dissemination physiognomy of therapy-resistant PC cells in vitro,and residual PC in vivo. Human PC cells exposed to ionizing radiation (IR), with/without HT-EA pre-treatment were examined for the alterations in the tumor invasion/metastasis (TIM) transcriptome (93 genes, QPCR-profiling). Utilizing a mouse model of residual PC, we investigated the benefit of HT-EA in the translation regulation of crucial TIM targets (TMA-IHC). Radiation activated 30, 50, 15, and 38 TIM molecules in surviving Panc-1, Panc-3.27, BxPC3, and MiaPaCa-2 cells. Of these, 15, 44, 12, and 26 molecules were suppressed with HT-EA pre-treatment. CXCR4 and COX2 exhibited cell-line-independent increases after IR, and was completely suppressed with HT-EA, across all PC cells. HT-EA treatment resulted in translational repression of IR-induced CXCR4, COX2, β-catenin, MMP9, Ki-67, BAPX, PhPT-1, MEGF10, and GRB10 in residual PC. Muting CXCR4 or COX2 regulated the migration/invasion potential of IR-surviving cells, while forced expression of CXCR4 or COX2 significantly increased migration/invasion capabilities of PC cells. Further, treatment with HT-EA significantly inhibited IR-induced and CXCR4/COX2 forced expression-induced PC cell migration/invasion. This study (i) documents the TIM blueprint in therapy-resistant PC cells, (ii) defines the role of CXCR4 and COX2 in induced metastatic potential, and (iii) recognizes the potential of HT-EA in deterring the CXCR4/COX2-dependent dissemination destiny of therapy-resistant residual PC cells.

Prognostic significance of COX-2 and β-catenin in colorectal ...

African Journals Online (AJOL)

Amani Kazem

2013-07-17

Jul 17, 2013 ... (wingless type) signaling pathway, increased protein concentrations promote transcription of genes .... under a light microscope and the histological type of colorectal .... of signet ring cell carcinoma showed weak COX-2 positivity. 3.2. Analysis .... COX-2 expression was detected in other tumors, and was be-.

Hepatic ischemia and reperfusion injury in the absence of myeloid cell-derived COX-2 in mice.

Directory of Open Access Journals (Sweden)

Sergio Duarte

Full Text Available Cyclooxygenase-2 (COX-2 is a mediator of hepatic ischemia and reperfusion injury (IRI. While both global COX-2 deletion and pharmacologic COX-2 inhibition ameliorate liver IRI, the clinical use of COX-2 inhibitors has been linked to increased risks of heart attack and stroke. Therefore, a better understanding of the role of COX-2 in different cell types may lead to improved therapeutic strategies for hepatic IRI. Macrophages of myeloid origin are currently considered to be important sources of the COX-2 in damaged livers. Here, we used a Cox-2flox conditional knockout mouse (COX-2-M/-M to examine the function of COX-2 expression in myeloid cells during liver IRI. COX-2-M/-M mice and their WT control littermates were subjected to partial liver ischemia followed by reperfusion. COX-2-M/-M macrophages did not express COX-2 upon lipopolysaccharide stimulation and COX-2-M/-M livers showed reduced levels of COX-2 protein post-IRI. Nevertheless, selective deletion of myeloid cell-derived COX-2 failed to ameliorate liver IRI; serum transaminases and histology were comparable in both COX-2-M/-M and WT mice. COX-2-M/-M livers, like WT livers, developed extensive necrosis, vascular congestion, leukocyte infiltration and matrix metalloproteinase-9 (MMP-9 expression post-reperfusion. In addition, myeloid COX-2 deletion led to a transient increase in IL-6 levels after hepatic reperfusion, when compared to controls. Administration of celecoxib, a selective COX-2 inhibitor, resulted in significantly improved liver function and histology in both COX-2-M/-M and WT mice post-reperfusion, providing evidence that COX-2-mediated liver IRI is caused by COX-2 derived from a source(s other than myeloid cells. In conclusion, these results support the view that myeloid COX-2, including myeloid-macrophage COX-2, is not responsible for the hepatic IRI phenotype.

Transcutaneous electrical nerve stimulation attenuates CFA-induced hyperalgesia and inhibits spinal ERK1/2-COX-2 pathway activation in rats.

Science.gov (United States)

Fang, Jun-Fan; Liang, Yi; Du, Jun-Ying; Fang, Jian-Qiao

2013-06-15

Transcutaneous electrical nerve stimulation (TENS) is a non-pharmacologic treatment for pain relief. In previous animal studies, TENS effectively alleviated Complete Freund's Adjuvant (CFA)- or carrageenan-induced inflammatory pain. Although TENS is known to produce analgesia via opioid activation in the brain and at the spinal level, few reports have investigated the signal transduction pathways mediated by TENS. Prior studies have verified the importance of the activation of extracellular signal-regulated kinase (ERK) signal transduction pathway in the spinal cord dorsal horn (SCDH) in acute and persistent inflammatory pains. Here, by using CFA rat model, we tested the efficacy of TENS on inhibiting the expressions of p-ERK1/2 and of its downstream cyclooxygenase-2 (COX-2) and the level of prostaglandin E2 (PGE2) at spinal level. Rats were randomly divided into control, model and TENS groups, and injected subcutaneously with 100 μl CFA or saline in the plantar surface of right hind paw. Rats in the TENS group were treated with TENS (constant aquare wave, 2 Hz and 100 Hz alternating frequencies, intensities ranging from 1 to 2 mA, lasting for 30 min each time) at 5 h and 24 h after injection. Paw withdrawal thresholds (PWTs) were measured with dynamic plantar aesthesiometer at 3d before modeling and 5 h, 6 h, and 25 h after CFA injection. The ipsilateral sides of the lumbar spinal cord dosral horns were harvested for detecting the expressions of p-ERK1/2 and COX-2 by western blot analysis and qPCR, and PGE2 by ELISA. CFA-induced periphery inflammation decreased PWTs and increased paw volume of rats. TENS treatment significantly alleviated mechanical hyperalgesia caused by CFA. However, no anti-inflammatory effect of TENS was observed. Expression of p-ERK1/2 protein and COX-2 mRNA was significantly up-regualted at 5 h and 6 h after CFA injection, while COX-2 and PGE2 protein level only increased at 6 h after modeling. Furthermore, the high expression of p-ERK1/2

Expression of VEGF, VEGFR, EGFR, COX-2 and MVD in cervical carcinoma, in relation with the response to radio-chemotherapy.

Science.gov (United States)

Nagy, Viorica Magdalena; Buiga, R; Brie, Ioana; Todor, N; Tudoran, Oana; Ordeanu, Claudia; Virág, Piroska; Tarta, Oana; Rus, Meda; Bălăcescu, O

2011-01-01

Despite the improvement in the treatment results due to modern irradiation techniques and to the association of chemo-radiotherapy, cervical cancer remains an unsolved problem of oncology both due to the increased rate of local failures and of the distant metastasis. Efforts to implement new therapeutic strategies in order to obtain better results in patients with cervical cancer appear justified. Neovascularization is an important step in the tumor progression and the therapeutic targeting of the tumor blood vessels appears to be a good strategy to follow in the anti-cancer treatment. Thus, even in an incipient phase of the clinical research process, the combination between the anti-angiogenic aimed therapies and the current radio-chemotherapy seems to represent a new, feasible and promising approach. The aim of the present study was to determine the prognostic and/or predictive value of some biological markers of tumor angiogenesis and of their implication in increasing the efficacy of current treatments for this cancer. So far, 54 women were included in a prospective trial: 44 having an advanced cervical carcinoma and 10 healthy women, as controls. A tumor biopsy and a blood sample were obtained from each patient before the start of therapy. The density of microvascularization was assessed using CD34 monoclonal antibody (hot spot technique), the expression of angiogenic factors VEGFR, EGFR and COX-2 were determined in tumor biopsies by specific immunohistochemistry techniques, using primary antibodies anti-EGFR, anti-VEGF and anti-COX-2 respectively. The quantitative polymerase chain reaction (Real Time PCR) was employed for assessing the expression level of the genes involved. Serum VEGF was determined by quantitative ELISA technique. Among the studied clinical and molecular factors, we found to be predictive for the type of response the following factors: tumor size at diagnosis (p=0.01), VEGFR2 expression (p=0.02) and a tendency to significance for patients

Ethanol enhances arsenic-induced cyclooxygenase-2 expression via both NFAT and NF-κB signalings in colorectal cancer cells

Energy Technology Data Exchange (ETDEWEB)

Wang, Lei; Hitron, John Andrew [Center for Research on Environmental Disease, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Toxicology and Cancer Biology, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Wise, James T.F. [Pharmacology and Nutritional Sciences, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Son, Young-Ok; Roy, Ram Vinod [Center for Research on Environmental Disease, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Toxicology and Cancer Biology, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Kim, Donghern; Dai, Jin [Toxicology and Cancer Biology, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Pratheeshkumar, Poyil [Center for Research on Environmental Disease, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Toxicology and Cancer Biology, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Zhang, Zhuo [Toxicology and Cancer Biology, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Xu, Mei; Luo, Jia [Pharmacology and Nutritional Sciences, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Shi, Xianglin, E-mail: xshi5@uky.edu [Center for Research on Environmental Disease, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States); Toxicology and Cancer Biology, College of Medicine, University of Kentucky, Lexington, KY 40536 (United States)

2015-10-15

Arsenic is a known carcinogen to humans, and chronic exposure to environmental arsenic is a worldwide health concern. As a dietary factor, ethanol carries a well-established risk for malignancies, but the effects of co-exposure to arsenic and ethanol on tumor development are not well understood. In the present study, we hypothesized that ethanol would enhance the function of an environmental carcinogen such as arsenic through increase in COX-2 expression. Our in vitro results show that ethanol enhanced arsenic-induced COX-2 expression. We also show that the increased COX-2 expression associates with intracellular ROS generation, up-regulated AKT signaling, with activation of both NFAT and NF-κB pathways. We demonstrate that antioxidant enzymes have an inhibitory effect on arsenic/ethanol-induced COX-2 expression, indicating that the responsive signaling pathways from co-exposure to arsenic and ethanol relate to ROS generation. In vivo results also show that co-exposure to arsenic and ethanol increased COX-2 expression in mice. We conclude that ethanol enhances arsenic-induced COX-2 expression in colorectal cancer cells via both the NFAT and NF-κB pathways. These results imply that, as a common dietary factor, ethanol ingestion may be a compounding risk factor for arsenic-induced carcinogenesis/cancer development. - Highlights: • Arsenic is able to induce Cox-2 expression in colorectal cancer cells. • Ethanol, a diet nutritional factor, could enhance arsenic-induced Cox-2. • The up-regulation of Cox-2 via both NFAT and NF-κB activities.

Ethanol enhances arsenic-induced cyclooxygenase-2 expression via both NFAT and NF-κB signalings in colorectal cancer cells

International Nuclear Information System (INIS)

Wang, Lei; Hitron, John Andrew; Wise, James T.F.; Son, Young-Ok; Roy, Ram Vinod; Kim, Donghern; Dai, Jin; Pratheeshkumar, Poyil; Zhang, Zhuo; Xu, Mei; Luo, Jia; Shi, Xianglin

2015-01-01

Arsenic is a known carcinogen to humans, and chronic exposure to environmental arsenic is a worldwide health concern. As a dietary factor, ethanol carries a well-established risk for malignancies, but the effects of co-exposure to arsenic and ethanol on tumor development are not well understood. In the present study, we hypothesized that ethanol would enhance the function of an environmental carcinogen such as arsenic through increase in COX-2 expression. Our in vitro results show that ethanol enhanced arsenic-induced COX-2 expression. We also show that the increased COX-2 expression associates with intracellular ROS generation, up-regulated AKT signaling, with activation of both NFAT and NF-κB pathways. We demonstrate that antioxidant enzymes have an inhibitory effect on arsenic/ethanol-induced COX-2 expression, indicating that the responsive signaling pathways from co-exposure to arsenic and ethanol relate to ROS generation. In vivo results also show that co-exposure to arsenic and ethanol increased COX-2 expression in mice. We conclude that ethanol enhances arsenic-induced COX-2 expression in colorectal cancer cells via both the NFAT and NF-κB pathways. These results imply that, as a common dietary factor, ethanol ingestion may be a compounding risk factor for arsenic-induced carcinogenesis/cancer development. - Highlights: • Arsenic is able to induce Cox-2 expression in colorectal cancer cells. • Ethanol, a diet nutritional factor, could enhance arsenic-induced Cox-2. • The up-regulation of Cox-2 via both NFAT and NF-κB activities.

Activating PTEN by COX-2 inhibitors antagonizes radiation-induced AKT activation contributing to radiosensitization

Energy Technology Data Exchange (ETDEWEB)

Meng, Zhen [Central Laboratory, Peking University School and Hospital of Stomatology, 22 Zhongguancun Avenue South, Haidian District, Beijing 100081 (China); Department of Oral & Maxillofacial Surgery, Peking University School and Hospital of Stomatology, 22 Zhongguancun Avenue South, Haidian District, Beijing 100081 (China); Gan, Ye-Hua, E-mail: kqyehuagan@bjmu.edu.cn [Central Laboratory, Peking University School and Hospital of Stomatology, 22 Zhongguancun Avenue South, Haidian District, Beijing 100081 (China); Department of Oral & Maxillofacial Surgery, Peking University School and Hospital of Stomatology, 22 Zhongguancun Avenue South, Haidian District, Beijing 100081 (China)

2015-05-01

Radiotherapy is still one of the most effective nonsurgical treatments for many tumors. However, radioresistance remains a major impediment to radiotherapy. Although COX-2 inhibitors can induce radiosensitization, the underlying mechanism is not fully understood. In this study, we showed that COX-2 selective inhibitor celecoxib enhanced the radiation-induced inhibition of cell proliferation and apoptosis in HeLa and SACC-83 cells. Treatment with celecoxib alone dephosphorylated phosphatase and tensin homolog deleted on chromosome ten (PTEN), promoted PTEN membrane translocation or activation, and correspondingly dephosphorylated or inactivated protein kinase B (AKT). By contrast, treatment with radiation alone increased PTEN phosphorylation, inhibited PTEN membrane translocation and correspondingly activated AKT in the two cell lines. However, treatment with celecoxib or another COX-2 selective inhibitor (valdecoxib) completely blocked radiation-induced increase of PTEN phosphorylation, rescued radiation-induced decrease in PTEN membrane translocation, and correspondingly inactivated AKT. Moreover, celecoxib could also upregulate PTEN protein expression by downregulating Sp1 expression, thereby leading to the activation of PTEN transcription. Our results suggested that COX-2 inhibitors could enhance radiosensitization at least partially by activating PTEN to antagonize radiation-induced AKT activation. - Highlights: • COX-2 inhibitor, celecoxib, could enhance radiosensitization. • Radiation induced PTEN inactivation (phosphorylation) and AKT activation. • COX-2 inhibitor induced PTEN expression and activation, and inactivated AKT. • COX-2 inhibitor enhanced radiosensitization through activating PTEN.

Effect of a hormone-releasing intrauterine system (Mirena® on aromatase and Cox-2 expression in patients with adenomyosis submitted or not, to endometrial resection

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Maia R

2012-04-01

Full Text Available Hugo Maia Jr1,2, Clarice Haddad1, Julio Casoy1, Rebeca Maia1, Nathanael Pinheiro3, Elsimar M Coutinho11Centro de Pesquisa e Assistência em Reprodução Humana (CEPARH, 2Itaigara Memorial Day Hospital, 3IMAGEPAT, Salvador, Bahia, BrazilObjective: To investigate the effect of a levonorgestrel-releasing intrauterine system (Mirena® on aromatase and cyclooxygenase-2 (Cox-2 expression in the endometrium of patients with adenomyosis who were submitted to endometrial resection at the time of insertion, compared to a group not submitted to endometrial resection and a group of controls with adenomyosis not submitted to any previous hormonal treatment.Patients and methods: Patients with adenomyosis (n = 89 were included in this study. Twenty-two patients had been using Mirena® for 5 years but had not been submitted to endometrial resection prior to insertion of the device. Twenty-four patients were submitted to endometrial resection at the time of Mirena® insertion. The remaining 43 patients with adenomyosis had undergone no previous hormonal treatment and served as a control group. Cox-2 and aromatase expression were determined in the endometrium by immunohistochemistry.Results: Use of Mirena® for 5 years reduced aromatase expression in the endometrium; however, this reduction was significantly greater in the uteri previously submitted to endometrial resection. The reduction in Cox-2 expression was significant only in the uteri submitted to endometrial resection followed by the insertion of Mirena®.Conclusion: Endometrial resection followed by the insertion of Mirena® was associated with greater rates of amenorrhea in patients with adenomyosis, which in turn were associated with a more effective inhibition of aromatase and Cox-2 expression in the endometrium.Keywords: aromatase, Mirena®, adenomyosis, Cox-2, endometrium, levonorgestrel

WIN 55,212-2 Inhibits the Epithelial Mesenchymal Transition of Gastric Cancer Cells via COX-2 Signals

Directory of Open Access Journals (Sweden)

Xiangshu Xian

2016-11-01

Full Text Available Background: Cannabinoids (the active components of Cannabis sativa and their derivatives have received considerable interest due to reports that they can affect the tumor growth, migration, and metastasis. Previous studies showed that the cannabinoid agonist WIN 55,212-2 (WIN was associated with gastric cancer (GC metastasis, but the mechanisms were unknown. Methods: The effects of WIN on GC cell migration and invasion were analyzed by the wound-healing assay and Transwell assay. Quantitative real-time PCR and Western blot were used to evaluate changes in expression of COX-2 and EMT associated markers in SGC7901 and AGS cells. Results: WIN inhibited cell migration, invasion, and epithelial to mesenchymal transition (EMT in GC. WIN treatment resulted in the downregulation of cyclooxygenase-2 (COX-2 expression and decreased the phosphorylation of AKT, and inhibited EMT in SGC7901 cells. Decreased expression of COX-2 and vimentin, and increased expression of E-cadherin, which was induced by WIN, were normalized by overexpression of AKT, suggesting that AKT mediated, at least partially, the WIN suppressed EMT of GC cells. Conclusion: WIN can inhibit the EMT of GC cells through the downregulation of COX-2.

Cyclooxygenase-2 expression in the normal human eye and its expression pattern in selected eye tumours

DEFF Research Database (Denmark)

Wang, Jinmei; Wu, Yazhen; Heegaard, Steffen

2011-01-01

Purpose: Cyclooxygenase-2 (COX-2) is an enzyme involved in neoplastic processes. The purpose of the present study is to investigate COX-2 expression in the normal human eye and the expression pattern in selected eye tumours involving COX-2 expressing cells. Methods: Immunohistochemical staining...... using antibodies against COX-2 was performed on paraffin sections of normal human eyes and selected eye tumours arising from cells expressing COX-2. Results: Cyclooxygenase-2 expression was found in various structures of the normal eye. Abundant expression was seen in the cornea, iris, ciliary body...... and retina. The COX-2 expression was less in tumours deriving from the ciliary epithelium and also in retinoblastoma. Conclusion: Cyclooxygenase-2 is constitutively expressed in normal human eyes. The expression of COX-2 is much lower in selected eye tumours involving COX-2 expressing cells....

Prognosis value of the COX-2 expression on radiotherapy efficiency and on survival without progression of patients reached by an unoperative glioblastoma; Valeur pronostique de l'expression de COX-2 sur l'efficacite de la radiotherapie et sur la survie sans progression des patients atteints d'un glioblastome inoperable

Energy Technology Data Exchange (ETDEWEB)

Simon, J.M.; Mazeron, J.J. [Groupe Hospitalier de la Pitie-Salepetriere, APHP, Service de Radiotherapie Oncologique, 75 - Paris (France); Mokhtari, K. [Groupe Hospitalier de la Pitie-Salepetriere, APHP, Lab. de Neuropathologie, 75 - Paris (France); Genestie, C. [Groupe Hospitalier de la Pitie-Salepetriere, APHP, Lab. d' Anatomie Pathologique, 75 - Paris (France); Bissery, A. [Groupe Hospitalier de la Pitie-Salepetriere, APHP, Dept. de biostatistiques et d' Anformation Medicale, 75 - Paris (France); Jaillon, P. [Hopital Saint-Antoine, Service de Pharmacologie, 75 - Paris (France)

2006-11-15

The expression of COX-2 is a prediction factor of the lack of response to the radiotherapy of glioblastomas and a less good survival rate without tumor progression, aside other known prognosis factors. These results suggest a selective treatment by an anti-COX-2 could have a radiosensitizer contribution during the radiotherapy of glioblastomas. (N.C.)

Macrophages From Irradiated Tumors Express Higher Levels of iNOS, Arginase-I and COX-2, and Promote Tumor Growth

International Nuclear Information System (INIS)

Tsai, C.-S.; Chen, F.-H.; Wang, C.-C.; Huang, H.-L.; Jung, Shih-Ming; Wu, C.-J.; Lee, C.-C.; McBride, William H.; Chiang, C.-S.; Hong, J.-H.

2007-01-01

Purpose: To investigate the effects of single and fractionated doses of radiation on tumors and tumor-associated macrophages (TAMs), and to elucidate the potential of TAMs to influence tumor growth. Methods and Materials: A murine prostate cell line, TRAMP-C1, was grown in C57Bl/6J mice to 4-mm tumor diameter and irradiated with either 25 Gy in a single dose, or 60 Gy in 15 fractions. The tumors were removed at the indicated times and assessed for a variety of markers related to TAM content, activation status, and function. Results: In tumors receiving a single radiation dose, arginase (Arg-I), and cycloxygenase-2 (COX-2) mRNA expression increased as a small transient wave within 24 h and a larger persistent wave starting after 3 days. Inducible nitric oxide synthase (iNOS) mRNA was elevated only after 3 days and continued to increase up to 3 weeks. After fractionated irradiation, Arg-1 and COX-2 mRNA levels increased within 5 days, whereas iNOS was increased only after 10 fractions of irradiation had been given. Increased levels of Arg-I, COX-2, and, to a lesser extent, iNOS protein were found to associate with TAMs 1-2 weeks after tumor irradiation. Function of TAMs were compared by mixing them with TRAMP-C1 cells and injecting them into mice; TRAMP-C1 cells mixed with TAMs from irradiated tumors appeared earlier and grew significantly faster than those mixed with TAMs from unirradiated tumors or TRAMP-C1 alone. Conclusions: Tumor-associated macrophages in the postirradiated tumor microenvironment express higher levels of Arg-1, COX-2, and iNOS, and promote early tumor growth in vivo

Tumor-produced, active Interleukin-1 β regulates gene expression in carcinoma-associated fibroblasts

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Dudas, Jozsef; Fullar, Alexandra; Bitsche, Mario; Schartinger, Volker; Kovalszky, Ilona; Sprinzl, Georg Mathias; Riechelmann, Herbert

2011-01-01

Recently we described a co-culture model of periodontal ligament (PDL) fibroblasts and SCC-25 lingual squamous carcinoma cells, which resulted in conversion of normal fibroblasts into carcinoma-associated fibroblasts (CAFs), and in epithelial-mesenchymal transition (EMT) of SCC-25 cells. We have found a constitutive high interleukin-1β (IL1-β) expression in SCC-25 cells in normal and in co-cultured conditions. In our hypothesis a constitutive IL1-β expression in SCC-25 regulates gene expression in fibroblasts during co-culture. Co-cultures were performed between PDL fibroblasts and SCC-25 cells with and without dexamethasone (DEX) treatment; IL1-β processing was investigated in SCC-25 cells, tumor cells and PDL fibroblasts were treated with IL1-β. IL1-β signaling was investigated by western blot and immunocytochemistry. IL1-β-regulated genes were analyzed by real-time qPCR. SCC-25 cells produced 16 kD active IL1-β, its receptor was upregulated in PDL fibroblasts during co-culture, which induced phosphorylation of interleukin-1 receptor-associated kinase-1 (IRAK-1), and nuclear translocalization of NFκBα. Several genes, including interferon regulatory factor 1 (IRF1) interleukin-6 (IL-6) and prostaglandin-endoperoxide synthase 2 (COX-2) were induced in CAFs during co-culture. The most enhanced induction was found for IL-6 and COX-2. Treatment of PDL fibroblasts with IL1-β reproduced a time- and dose-dependent upregulation of IL1-receptor, IL-6 and COX-2. A further proof was achieved by DEX inhibition for IL1-β-stimulated IL-6 and COX-2 gene expression. Constitutive expression of IL1-β in the tumor cells leads to IL1-β-stimulated gene expression changes in tumor-associated fibroblasts, which are involved in tumor progression. -- Graphical abstract: SCC-25 cells produce active, processed IL1-β. PDL fibroblasts possess receptor for IL1-β, and its expression is increased 4.56-times in the presence of SCC-25 tumor cells. IL1-β receptor expression in

Tumor-produced, active Interleukin-1 {beta} regulates gene expression in carcinoma-associated fibroblasts

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Dudas, Jozsef, E-mail: Jozsef.Dudas@i-med.ac.at [Department of Otorhinolaryngology, Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck (Austria); Fullar, Alexandra, E-mail: fullarsz@gmail.com [Department of Otorhinolaryngology, Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck (Austria); 1st Institute of Pathology and Experimental Cancer Research, Semmelweis University, Ulloei ut 26, H-1085 Budapest (Hungary); Bitsche, Mario, E-mail: Mario.Bitsche@i-med.ac.at [Department of Otorhinolaryngology, Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck (Austria); Schartinger, Volker, E-mail: Volker.Schartinger@i-med.ac.at [Department of Otorhinolaryngology, Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck (Austria); Kovalszky, Ilona, E-mail: koval@korb1.sote.hu [1st Institute of Pathology and Experimental Cancer Research, Semmelweis University, Ulloei ut 26, H-1085 Budapest (Hungary); Sprinzl, Georg Mathias, E-mail: Georg.Sprinzl@i-med.ac.at [Department of Otorhinolaryngology, Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck (Austria); Riechelmann, Herbert, E-mail: Herbert.Riechelmann@i-med.ac.at [Department of Otorhinolaryngology, Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck (Austria)

2011-09-10

Recently we described a co-culture model of periodontal ligament (PDL) fibroblasts and SCC-25 lingual squamous carcinoma cells, which resulted in conversion of normal fibroblasts into carcinoma-associated fibroblasts (CAFs), and in epithelial-mesenchymal transition (EMT) of SCC-25 cells. We have found a constitutive high interleukin-1{beta} (IL1-{beta}) expression in SCC-25 cells in normal and in co-cultured conditions. In our hypothesis a constitutive IL1-{beta} expression in SCC-25 regulates gene expression in fibroblasts during co-culture. Co-cultures were performed between PDL fibroblasts and SCC-25 cells with and without dexamethasone (DEX) treatment; IL1-{beta} processing was investigated in SCC-25 cells, tumor cells and PDL fibroblasts were treated with IL1-{beta}. IL1-{beta} signaling was investigated by western blot and immunocytochemistry. IL1-{beta}-regulated genes were analyzed by real-time qPCR. SCC-25 cells produced 16 kD active IL1-{beta}, its receptor was upregulated in PDL fibroblasts during co-culture, which induced phosphorylation of interleukin-1 receptor-associated kinase-1 (IRAK-1), and nuclear translocalization of NF{kappa}B{alpha}. Several genes, including interferon regulatory factor 1 (IRF1) interleukin-6 (IL-6) and prostaglandin-endoperoxide synthase 2 (COX-2) were induced in CAFs during co-culture. The most enhanced induction was found for IL-6 and COX-2. Treatment of PDL fibroblasts with IL1-{beta} reproduced a time- and dose-dependent upregulation of IL1-receptor, IL-6 and COX-2. A further proof was achieved by DEX inhibition for IL1-{beta}-stimulated IL-6 and COX-2 gene expression. Constitutive expression of IL1-{beta} in the tumor cells leads to IL1-{beta}-stimulated gene expression changes in tumor-associated fibroblasts, which are involved in tumor progression. -- Graphical abstract: SCC-25 cells produce active, processed IL1-{beta}. PDL fibroblasts possess receptor for IL1-{beta}, and its expression is increased 4.56-times in the

Involvement of COX-2 in nickel elution from a wire implanted subcutaneously in mice.

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Sato, Taiki; Kishimoto, Yu; Asakawa, Sanki; Mizuno, Natsumi; Hiratsuka, Masahiro; Hirasawa, Noriyasu

2016-07-01

Many types of medical alloys include nickel (Ni), and the elution of Ni ions from these materials causes toxicities and inflammation. We have previously reported that inflammation enhances Ni elution, although the molecular mechanisms underlying this effect remain unclear. In this study, we investigated how inflammatory responses enhanced Ni elution in a wire-implantation mouse model. Subcutaneous implantation of Ni wire induced the expression of cyclooxygenase-2 (COX-2) and microsomal prostaglandin E synthase-1 (mPGES-1) mRNA in the surrounding tissues. Immunostaining analysis showed that cells expressing COX-2 were mainly fibroblast-like cells 8h after implantation of a Ni wire, but were mainly infiltrated leukocytes at 24h. NiCl2 induced the expression of COX-2 mRNA in primary fibroblasts, neutrophils, RAW 264 cells, and THP-1 cells, indicating that Ni ions can induce COX-2 expression in various types of cells. The elution of Ni ions from the implanted Ni wire at 8h was reduced by dexamethasone (Dex), indomethacin (Ind), or celecoxib (Cel) treatment. Ni wire implantation induced an increase in mRNA levels for anaerobic glycolytic pathway components glucose transporter 1 (GLUT1), hexokinase 2 (HK2), lactate dehydrogenase A (LDHA), and monocarboxylate transporter 4 (MCT4); the expression of these genes was also inhibited by Dex, Ind, and Cel. In primary fibroblasts, the expression of these mRNAs and the production of lactate were induced by NiCl2 and further potentiated by PGE2. Furthermore, Ni wire-induced infiltration of inflammatory leukocytes was significantly reduced by Dex, Ind, or Cel. Depletion of neutrophils with a specific antibody caused reduction of both leukocyte infiltration and Ni elution. These results indicate that Ni ions eluted from wire induced COX-2 expression, which further promoted elution of Ni ions by increasing lactate production and leukocyte infiltration. Since COX inhibitors and Dex reduced the elution of Ni ions, these drugs may be

Early increased density of cyclooxygenase-2 (COX-2 immunoreactive neurons in Down syndrome

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Maria Mulet

2017-06-01

Full Text Available Neuroinflammation is one of the hallmarks of Alzheimer’s disease. One of the enzymes involved in neuroinflammation, even in early stages of the disease, is COX-2, an inducible cyclooxygenase responsible for the generation of eicosanoids and for the generation of free radicals. Individuals with Down syndrome develop Alzheimer’s disease early in life. Previous studies pointed to the possible overexpression of COX-2 and correlated it to brain regions affected by the disease. We analysed the COX-2 expression levels in individuals with Down syndrome and in young, adult and old mice of the Ts65Dn mouse model for Down syndrome. We have observed an overexpression of COX-2 in both, Down syndrome individuals and mice. Importantly, mice already presented an overexpression of COX-2 at postnatal day 30, before neurodegeneration begins; which suggests that neuroinflammation may underlie the posterior neurodegeneration observed in individuals with Down syndrome and in Ts65Dn mice and could be a factor for the premature appearance of Alzheimer’s disease.

Ethyl acetate extract from Asparagus cochinchinensis exerts anti-inflammatory effects in LPS-stimulated RAW264.7 macrophage cells by regulating COX-2/iNOS, inflammatory cytokine expression, MAP kinase pathways, the cell cycle and anti-oxidant activity

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Lee, Hyun Ah; Koh, Eun Kyoung; Sung, Ji Eun; Kim, Ji Eun; Song, Sung Hwa; Kim, Dong Seob; Son, Hong Joo; Lee, Chung Yeoul; Lee, Hee Seob; Bae, Chang Joon; Hwang, Dae Youn

2017-01-01

Asparagus cochinchinesis (A. cochinchinesis) is a medicine traditionally used to treat fever, cough, kidney disease, breast cancer, inflammatory disease and brain disease in northeast Asian countries. Although numerous studies of the anti-inflammatory effects of A. cochinchinesis have been conducted, the underlying mechanisms of such effects in macrophages remain to be demonstrated. To investigate the mechanism of suppressive effects on the inflammatory response in macrophages, alterations of the nitric oxide (NO) level, the cell viability, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression levels, inflammatory cytokine expression, the mitogen-activated protein kinase (MAPK) signaling pathway, cell cycle arrest and reactive oxygen species (ROS) levels were measured in lipopolysaccharide (LPS)-activated RAW264.7 cells following treatment with ethyl acetate extract from A. cochinchinesis root (EaEAC). RAW264.7 cells pretreated two different concentrations of EaEAC prior to LPS treatment exhibited no significant toxicity. The concentration of NO was significantly decreased in the EaEAC + LPS treated group compared with the vehicle + LPS treated group. A similar decrease in mRNA transcript level of COX-2, iNOS, pro-inflammatory cytokines [tumor necrosis factor-α and interleukin (IL)-1β] and anti-inflammatory cytokines (IL-6 and IL-10) was detected in the EaEAC + LPS treated group compared with the vehicle + LPS treated group, although the decrease rate varied. Enhancement of the phosphorylation of MAPK family members following LPS treatment was partially rescued in the EaEAC pretreated group, and the cell cycle was arrested at the G2/M phase. Furthermore, the EaEAC pretreated group exhibited a reduced level of ROS generation compared with the vehicle + LPS treated group. Taken together, these results suggest that EaEAC suppresses inflammatory responses through inhibition of NO production, COX-2 expression and ROS production, as well as

Prostaglandin E2 stimulates Fas ligand expression via the EP1 receptor in colon cancer cells.

LENUS (Irish Health Repository)

O'Callaghan, G

2012-02-03

Fas ligand (FasL\\/CD95L) is a member of the tumour necrosis factor superfamily that triggers apoptosis following crosslinking of the Fas receptor. Despite studies strongly implicating tumour-expressed FasL as a major inhibitor of the anti-tumour immune response, little is known about the mechanisms that regulate FasL expression in tumours. In this study, we show that the cyclooxygenase (COX) signalling pathway, and in particular prostaglandin E(2) (PGE(2)), plays a role in the upregulation of FasL expression in colon cancer. Suppression of either COX-2 or COX-1 by RNA interference in HCA-7 and HT29 colon tumour cells reduced FasL expression at both the mRNA and protein level. Conversely, stimulation with PGE(2) increased FasL expression and these cells showed increased cytotoxicity against Fas-sensitive Jurkat T cells. Prostaglandin E(2)-induced FasL expression was mediated by signalling via the EP1 receptor. Moreover, immunohistochemical analysis using serial sections of human colon adenocarcinomas revealed a strong positive correlation between COX-2 and FasL (r=0.722; P<0.0001) expression, and between EP1 receptor and FasL (r=0.740; P<0.0001) expression, in the tumour cells. Thus, these findings indicate that PGE(2) positively regulates FasL expression in colon tumour cells, adding another pro-neoplastic activity to PGE(2).

Atorvastatin reduces lipopolysaccharide-induced expression of cyclooxygenase-2 in human pulmonary epithelial cells

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Chen Ping

2005-04-01

Full Text Available Abstract Objective To explore the effects of atorvastatin on expression of cyclooxygenase-2 (COX-2 in human pulmonary epithelial cells (A549. Methods A549 cells were incubated in DMEM medium containing lipopolysaccharide (LPS in the presence or absence of atorvastatin. After incubation, the medium was collected and the amount of prostaglandin E2 (PGE2 was measured by enzyme-linked immunosorbent assay (ELISA. The cells were harvested, and COX-2 mRNA and protein were analyzed by RT-PCR and western-blot respectively. Results LPS increased the expression of COX-2 mRNA and production of PGE2 in a dose- and time-dependent manner in A549. Induction of COX-2 mRNA and protein by LPS were inhibited by atorvastatin in a dose-dependent manner. Atorvastatin also significantly decreased LPS-induced production of PGE2. There was a positive correlation between reduced of COX-2 mRNA and decreased of PGE2 (r = 0.947, P Conclusion Atorvastatin down-regulates LPS-induced expression of the COX-2 and consequently inhibits production of PGE2 in cultured A549 cells.

COX-2 verexpression in pretreatment biopsies predicts response of rectal cancers to neoadjuvant radiochemotherapy

International Nuclear Information System (INIS)

Smith, Fraser M.; Reynolds, John V.; Kay, Elaine W.; Crotty, Paul; Murphy, James O.; Hollywood, Donal; Gaffney, Eoin F.; Stephens, Richard B.; Kennedy, M. John

2006-01-01

Purpose: To determine the utility of COX-2 expression as a response predictor for patients with rectal cancer who are undergoing neoadjuvant radiochemotherapy (RCT). Methods and Materials: Pretreatment biopsies (PTB) from 49 patients who underwent RCT were included. COX-2 and proliferation in PTB were assessed by immunohistochemistry (IHC) and apoptosis was detected by TUNEL stain. Response to treatment was assessed by a 5-point tumor-regression grade (TRG) based on the ratio of residual tumor to fibrosis. Results: Good response (TRG 1 + 2), moderate response (TRG 3), and poor response (TRG 4 + 5) were seen in 21 patients (42%), 11 patients (22%), and 17 patients (34%), respectively. Patients with COX-2 overexpression in PTB were more likely to demonstrate moderate or poor response (TRG 3 + 4) to treatment than were those with normal COX-2 expression (p = 0.026, chi-square test). Similarly, poor response was more likely if patients had low levels of spontaneous apoptosis in PTBs (p = 0.0007, chi-square test). Conclusions: COX-2 overexpression and reduced apoptosis in PTB can predict poor response of rectal cancer to RCT. As COX-2 inhibitors are commercially available, their administration to patients who overexpress COX-2 warrants assessment in clinical trials in an attempt to increase overall response rates

Areca nut components affect COX-2, cyclin B1/cdc25C and keratin expression, PGE2 production in keratinocyte is related to reactive oxygen species, CYP1A1, Src, EGFR and Ras signaling.

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Mei-Chi Chang

Full Text Available Chewing of betel quid (BQ increases the risk of oral cancer and oral submucous fibrosis (OSF, possibly by BQ-induced toxicity and induction of inflammatory response in oral mucosa.Primary gingival keratinocytes (GK cells were exposed to areca nut (AN components with/without inhibitors. Cytotoxicity was measured by 3-(4,5-dimethyl- thiazol- 2-yl-2,5-diphenyl-tetrazolium bromide (MTT assay. mRNA and protein expression was evaluated by reverse transcriptase-polymerase chain reaction (RT-PCR and western blotting. PGE2/PGF2α production was measured by enzyme-linked immunosorbent assays.Areca nut extract (ANE stimulated PGE2/PGF2α production, and upregulated the expression of cyclooxygenase-2 (COX-2, cytochrome P450 1A1 (CYP1A1 and hemeoxygenase-1 (HO-1, but inhibited expression of keratin 5/14, cyclinB1 and cdc25C in GK cells. ANE also activated epidermal growth factor receptor (EGFR, Src and Ras signaling pathways. ANE-induced COX-2, keratin 5, keratin 14 and cdc25C expression as well as PGE2 production were differentially regulated by α-naphthoflavone (a CYP 1A1/1A2 inhibitor, PD153035 (EGFR inhibitor, pp2 (Src inhibitor, and manumycin A (a Ras inhibitor. ANE-induced PGE2 production was suppressed by piper betle leaf (PBL extract and hydroxychavicol (two major BQ components, dicoumarol (aQuinone Oxidoreductase--NQO1 inhibitor and curcumin. ANE-induced cytotoxicity was inhibited by catalase and enhanced by dicoumarol, suggesting that AN components may contribute to the pathogenesis of OSF and oral cancer via induction of aberrant differentiation, cytotoxicity, COX-2 expression, and PGE2/PGF2α production.CYP4501A1, reactive oxygen species (ROS, EGFR, Src and Ras signaling pathways could all play a role in ANE-induced pathogenesis of oral cancer. Addition of PBL into BQ and curcumin consumption could inhibit the ANE-induced inflammatory response.

STAT3 and NF-κB are common targets for kaempferol-mediated attenuation of COX-2 expression in IL-6-induced macrophages and carrageenan-induced mouse paw edema

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Anandita Basu

2017-12-01

Full Text Available Cycloxygenase-2 (COX-2 is the inducible isoform of cycloxygenase enzyme family that catalyzes synthesis of inflammatory mediators, prostanoids and prostaglandins, and therefore, can be targeted by anti-inflammatory drugs. Here, we showed a plant polyphenol, kaempferol, attenuated IL-6-induced COX-2 expression in human monocytic THP-1 cells suggesting its beneficial role in chronic inflammation. Kaempferol deactivated and prevented nuclear localization of two major transcription factors STAT3 and NF-κB, mutually responsible for COX-2 induction in response to IL-6. Moreover, STAT3 and NF-κB were simultaneously deactivated by kaempferol in acute inflammation, as shown by carrageenan-induced mouse paw edema model. The concomitant reduction in COX-2 expression in paw tissues suggested kaempferol’s role in mitigation of inflammation by targeting STAT3 and NF-κB.

Inhibition of COX-2 does not affect therapeutical result of photodynamic therapy with hypericin despite of its increased activity and expression

International Nuclear Information System (INIS)

Mikes, J.; Kleban, J.; Kulikova, L.; Sackova, V.; Fedorocko, P.

2006-01-01

A photodynamic therapy (PDT) is a very promising, flexible and multifarious therapeutical approach for the treatment of malignant as well as non-malignant disorders. It is beholden on a nature of a photosensitive compound, its concentration and an incubation time, on a wavelength of light radiation, a fluence rate and a light dose as well as on a histological origin of the tissue and an oxygen pressure in it. Although PDT is of use in clinical practice, new promising photosensitive compounds with advantageous attributes are discovered continuously. PDT with hypericin, one of promising photosensitizers, activates p38 MAPK signalling pathway which induces expression of COX-2 and thereby increases concentration of its main product PGE2. Elevated activity of COX-2 as such is considered as contradictory to photo-cytotoxic effect of PDT with hypericin which should negatively influence an efficacy of PDT. In our experiment, effect of rofecoxib, a specific COX-2 inhibitor, as a post-treatment after PDT with hypericin in HeLa and HT29 cells have been evaluated. 24 as well as 48 hour treatment with 1 μM rofecoxib applied immediately after PDT did not induce significant decrease in cell proliferation, surprisingly. Purpose of failure to increase efficacy of PDT might be an activation of anti-apoptotic signalling pathways. Levels of Bcl-2 family proteins, especially Mcl-1 (HT29 and HeLa) and Bcl-2 (not expressed in HT29) have been evaluated. Considering our results, we can predict, that activity of COX-2 and its inhibition does not play crucial task in PDT experiments in vitro however its importance manifests in vivo as it affects angiogenesis of tumor. (authors)

Combined Analysis of COX-2 and p53 Expressions Reveals Synergistic Inverse Correlations with Microsatellite Instability and CpG Island Methylator Phenotype in Colorectal Cancer

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Shuji Ogino

2006-06-01

Full Text Available Cyclooxygenase-2 (COX-2 overexpression and mutations of p53 (a known COX-2 regulator are inversely associated with microsatellite instability—high (MSI-H and CpG island methylator phenotype (CIMP, characterized by extensive promoter methylation, is associated with MSI-H. However, no studies have comprehensively examined interrelations between COX-2, p53, MSI, and CIMP. Using MethyLight, we measured DNA methylation in five CIMP-specific gene promoters [CACNA1G, CDKN2A (p16/INK4A, CRABP1, MLH1, and NEUROG1] in relatively unbiased samples of 751 colorectal cancer cases obtained from two large prospective cohorts; 115 (15% tumors were CIMP-high (≥ 4 of 5 methylated promoters, 251 (33% were CIMP-low (1 to 3 methylated promoters, and the remaining 385 (51% were CIMP-0 (no methylated promoters. CIMP-high tumors were much less frequent in COX-2+/p53+ tumors (4.6% than in COX-2+/p53- tumors (19%; P < .0001, COX-2-/p53+ tumors (17%; P = .04, and COX-2-/p53- tumors (28%; P < .0001. In addition, COX-2+/p53+ tumors were significantly less common in MSI-H CIMP-high tumors (9.7% than in non-MSI-H CIMP-low/CIMP-0 tumors (44–47%; P < .0001. In conclusion, COX-2 and p53 alterations were synergistically inversely correlated with both MSI-H and CIMP-high. Our data suggest that a combined analysis of COX-2 and p53 may be more useful for the molecular classification of colorectal cancer than either COX-2 or p53 analysis alone.

Cytotoxic of Ganoderma lucidum in Colon Cancer through Cyclooxygenase 2 (COX-2 as Its Molecular Target

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Agustina Setiawati

2017-05-01

Full Text Available Many studies were designed explore chemopreventive activity of natural products on colon cancer especially addressing COX-2 as molecular target. Another promising source of natural product that potentially exhibit anticancer activity on colon cancer is Ganoderma lucidum. This study assessed selectivity of cytotoxic effect of G. lucidum extract on WiDr to Vero cells and investigated molecular mechanism on COX-2. G. lucidum ex-tract was prepared by reflux extraction method; in vitro anticancer was assayed by MTT method on WiDr and Vero cell line. This study applied apoptosis induction assay to observe cell death mechanism using double staining method; further COX-2 expression was stained by immunocytochemistry method. G. lucidum extract has cytotoxic effect on WiDr cells with IC50 135 µg/mL. However, the cytotoxic effect had low selectivity to-wards Vero cells with Selectivity Index (SI 3.66. The extract induced apoptosis and suppressed COX-2 ex-pression in WiDr cells. G. lucidum extract was potential to be developed as anticancer agent towards colon cancer.

Canolol inhibits gastric tumors initiation and progression through COX-2/PGE2 pathway in K19-C2mE transgenic mice.

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Donghui Cao

Full Text Available 4-Vinyl-2, 6-dimethoxyphenol (canolol is an antioxidant phenolic compound extracted from crude canola oil. In current research, K19-C2mE transgenic mice, developing hyperplastic tumors spontaneously in the glandular stomach, were used to study the mechanisms involved in the anti-inflammation and anti-tumor effects of canolol. Tg mice receiving canolol diet had a reduced tumor incidence, to 41.2%, compared with Non-treatment Tg mice, 77.8% of which had gastric tumor (P=0.002. Besides that, the mean tumor diameter was decreased from 6.5 mm to 4.5 mm (P<0.001 after canolol administration. COX-2/PGE2 pathway is known to play pivotal role in inflammation-induced gastric tumorigenesis. The neutrophils and lymphocytes infiltration was suppressed significantly, and the mRNA levels of the proinflammatory cytokines COX-2, IL-1β and IL-12b were also downregulated in gastric mucosa. Additionally, immunohistochemical analysis showed that COX-2, EP2, Gαs and β-catenin, key factors involving in PGE2 signal transduction, were positive staining with higher H scores in Non-treatment Tg mice, while the expressions were suppressed significantly by 0.1% canolol (P<0.001. In addition, tumor-suppressor miR-7 was reactivated after canolol administration, and COX-2 was showed to be a functional target of miR-7 to suppress the tumor progression. In conclusion, canolol could inhibit the gastritis-related tumor initiation and progression, and the suppression effect was correlated with the blocking up of canonical COX-2/PGE2 signaling pathway and might be regulated by miR-7.

Regulation of p53, nuclear factor κB and cyclooxygenase-2 expression by bromelain through targeting mitogen-activated protein kinase pathway in mouse skin

International Nuclear Information System (INIS)

Kalra, Neetu; Bhui, Kulpreet; Roy, Preeti; Srivastava, Smita; George, Jasmine; Prasad, Sahdeo; Shukla, Yogeshwer

2008-01-01

Bromelain is a pharmacologically active compound, present in stems and immature fruits of pineapples (Ananas cosmosus), which has been shown to have anti-edematous, anti-inflammatory, anti-thrombotic and anti-metastatic properties. In the present study, antitumorigenic activity of bromelain was recorded in 7,12-dimethylbenz(a)anthracene (DMBA)-initiated and 12-O-tetradecanoylphorbol-13-acetate (TPA)-promoted 2-stage mouse skin model. Results showed that bromelain application delayed the onset of tumorigenesis and reduced the cumulative number of tumors, tumor volume and the average number of tumors/mouse. To establish a cause and effect relationship, we targeted the proteins involved in the cell death pathway. Bromelain treatment resulted in upregulation of p53 and Bax and subsequent activation of caspase 3 and caspase 9 with concomitant decrease in antiapoptotic protein Bcl-2 in mouse skin. Since persistent induction of cyclooxygenase-2 (Cox-2) is frequently implicated in tumorigenesis and is regulated by nuclear factor-kappa B (NF-κB), we also investigated the effect of bromelain on Cox-2 and NF-κB expression. Results showed that bromelain application significantly inhibited Cox-2 and inactivated NF-κB by blocking phosphorylation and subsequent degradation of IκBα. In addition, bromelain treatment attenuated DMBA-TPA-induced phosphorylation of extracellular signal-regulated protein kinase (ERK1/2), mitogen-activated protein kinase (MAPK) and Akt. Taken together, we conclude that bromelain induces apoptosis-related proteins along with inhibition of NF-κB-driven Cox-2 expression by blocking the MAPK and Akt/protein kinase B signaling in DMBA-TPA-induced mouse skin tumors, which may account for its anti-tumorigenic effects

Cyclooxygenase-2 expression in oligodendrocytes increases sensitivity to excitotoxic death

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Rojas Monica A

2010-04-01

Full Text Available Abstract Background We previously found that cyclooxygenase 2 (COX-2 was expressed in dying oligodendrocytes at the onset of demyelination in the Theiler's murine encephalomyelitis virus-induced demyelinating disease (TMEV-IDD model of multiple sclerosis (MS (Carlson et al. J.Neuroimmunology 2006, 149:40. This suggests that COX-2 may contribute to death of oligodendrocytes. Objective The goal of this study was to examine whether COX-2 contributes to excitotoxic death of oligodendrocytes and potentially contributes to demyelination. Methods The potential link between COX-2 and oligodendrocyte death was approached using histopathology of MS lesions to examine whether COX-2 was expressed in dying oligodendrocytes. COX-2 inhibitors were examined for their ability to limit demyelination in the TMEV-IDD model of MS and to limit excitotoxic death of oligodendrocytes in vitro. Genetic manipulation of COX-2 expression was used to determine whether COX-2 contributes to excitotoxic death of oligodendrocytes. A transgenic mouse line was generated that overexpressed COX-2 in oligodendrocytes. Oligodendrocyte cultures derived from these transgenic mice were used to examine whether increased expression of COX-2 enhanced the vulnerability of oligodendrocytes to excitotoxic death. Oligodendrocytes derived from COX-2 knockout mice were evaluated to determine if decreased COX-2 expression promotes a greater resistance to excitotoxic death. Results COX-2 was expressed in dying oligodendrocytes in MS lesions. COX-2 inhibitors limited demyelination in the TMEV-IDD model of MS and protected oligodendrocytes against excitotoxic death in vitro. COX-2 expression was increased in wild-type oligodendrocytes following treatment with Kainic acid (KA. Overexpression of COX-2 in oligodendrocytes increased the sensitivity of oligodendrocytes to KA-induced excitotoxic death eight-fold compared to wild-type. Conversely, oligodendrocytes prepared from COX-2 knockout mice showed a

Biphasic Modulation of NOS Expression, Protein and Nitrite Products by Hydroxocobalamin Underlies Its Protective Effect in Endotoxemic Shock: Downstream Regulation of COX-2, IL-1β, TNF-α, IL-6, and HMGB1 Expression

Science.gov (United States)

Sampaio, André L. F.; Dalli, Jesmond; Brancaleone, Vincenzo; D'Acquisto, Fulvio; Perretti, Mauro; Wheatley, Carmen

2013-01-01

Background. NOS/•NO inhibitors are potential therapeutics for sepsis, yet they increase clinical mortality. However, there has been no in vivo investigation of the (in vitro) •NO scavenger, cobalamin's (Cbl) endogenous effects on NOS/•NO/inflammatory mediators during the immune response to sepsis. Methods. We used quantitative polymerase chain reaction (qPCR), ELISA, Western blot, and NOS Griess assays, in a C57BL/6 mouse, acute endotoxaemia model. Results. During the immune response, pro-inflammatory phase, parenteral hydroxocobalamin (HOCbl) treatment partially inhibits hepatic, but not lung, iNOS mRNA and promotes lung eNOS mRNA, but attenuates the LPS hepatic rise in eNOS mRNA, whilst paradoxically promoting high iNOS/eNOS protein translation, but relatively moderate •NO production. HOCbl/NOS/•NO regulation is reciprocally associated with lower 4 h expression of TNF-α, IL-1β, COX-2, and lower circulating TNF-α, but not IL-6. In resolution, 24 h after LPS, HOCbl completely abrogates a major late mediator of sepsis mortality, high mobility group box 1 (HMGB1) mRNA, inhibits iNOS mRNA, and attenuates LPS-induced hepatic inhibition of eNOS mRNA, whilst showing increased, but still moderate, NOS activity, relative to LPS only. experiments (LPS+D-Galactosamine) HOCbl afforded significant, dose-dependent protection in mice Conclusions. HOCbl produces a complex, time- and organ-dependent, selective regulation of NOS/•NO during endotoxaemia, corollary regulation of downstream inflammatory mediators, and increased survival. This merits clinical evaluation. PMID:23781123

Celecoxib Down-Regulates the Hypoxia-Induced Expression of HIF-1α and VEGF Through the PI3K/AKT Pathway in Retinal Pigment Epithelial Cells

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Yi-zhou Sun

2017-12-01

Full Text Available Background/Aims: The goal of this study was to detect the expression of hypoxia-inducible factor 1α (HIF-1α and vascular endothelial growth factor (VEGF in human retinal pigmented epithelial (RPE cells treated with celecoxib, a selective cyclooxygenase-2 (COX-2 inhibitor, under hypoxic and normoxic conditions and to explore the signaling mechanism involved in regulating the hypoxia-induced expression of HIF-1α and VEGF in RPE cells. Methods: D407 cells were cultured in normoxic or hypoxic conditions, with or without celecoxib or a PI3K inhibitor (LY294002. The anti-proliferative effect of celecoxib was assessed using the MTT assay. RT-PCR, Western blotting and ELISA were performed to detect the levels of PI3K, phosphorylated AKT (p-AKT, HIF-1α, VEGF and COX-2. Results: Celecoxib inhibited the proliferation of RPE cells in a dose-dependent manner. Celecoxib suppressed the expression of VEGF at both the mRNA and protein levels and decreased HIF-1α protein expression. HIF-1α activation was regulated by the PI3K/AKT pathway. The celecoxib-induced down-regulation of HIF-1α and VEGF required the suppression of the hypoxia-induced PI3K/AKT pathway. However, the down-regulation of COX-2 did not occur in cells treated with celecoxib. Conclusions: The antiangiogenic effects of celecoxib in RPE cells under hypoxic conditions resulted from the inhibition of HIF-1α and VEGF expression, which may be partly mediated by a COX-2-independent, PI3K/AKT-dependent pathway.

Stromal COX-2 signaling activated by deoxycholic acid mediates proliferation and invasiveness of colorectal epithelial cancer cells

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Zhu, Yingting; Zhu, Min; Lance, Peter

2012-01-01

Highlights: ► Human colonic cancer associated fibroblasts are major sources of COX-2 and PGE 2 . ► The fibroblasts interact with human colonic epithelial cancer cells. ► Activation of COX-2 signaling in the fibroblasts affects behavior of the epithelia. ► Protein Kinase C controls the activation of COX-2 signaling. -- Abstract: COX-2 is a major regulator implicated in colonic cancer. However, how COX-2 signaling affects colonic carcinogenesis at cellular level is not clear. In this article, we investigated whether activation of COX-2 signaling by deoxycholic acid (DCA) in primary human normal and cancer associated fibroblasts play a significant role in regulation of proliferation and invasiveness of colonic epithelial cancer cells. Our results demonstrated while COX-2 signaling can be activated by DCA in both normal and cancer associated fibroblasts, the level of activation of COX-2 signaling is significantly greater in cancer associated fibroblasts than that in normal fibroblasts. In addition, we discovered that the proliferative and invasive potential of colonic epithelial cancer cells were much greater when the cells were co-cultured with cancer associated fibroblasts pre-treated with DCA than with normal fibroblasts pre-treated with DCA. Moreover, COX-2 siRNA attenuated the proliferative and invasive effect of both normal and cancer associate fibroblasts pre-treated with DCA on the colonic cancer cells. Further studies indicated that the activation of COX-2 signaling by DCA is through protein kinase C signaling. We speculate that activation of COX-2 signaling especially in cancer associated fibroblasts promotes progression of colonic cancer.

Cox2 and β-Catenin/T-cell Factor Signaling Intestinalize Human Esophageal Keratinocytes When Cultured under Organotypic Conditions

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Jianping Kong

2011-09-01

Full Text Available The incidence of esophageal adenocarcinoma (EAC is rising in the United States. An important risk factor for EAC is the presence of Barrett esophagus (BE. BE is the replacement of normal squamous esophageal epithelium with a specialized columnar epithelium in response to chronic acid and bile reflux. However, the emergence of BE from squamous keratinocytes has not yet been demonstrated. Our research has focused on this. Wnt and cyclooxygenase 2 (Cox2 are two pathways whose activation has been associated with BE and progression to EAC, but their role has not been tested experimentally. To explore their contribution, we engineered a human esophageal keratinocyte cell line to express either a dominant-active Wnt effector CatCLef or a Cox2 complementary DNA. In a two-dimensional culture environment, Cox2 expression increases cell proliferation and migration, but neither transgene induces known BE markers. In contrast, when these cells were placed into three-dimensional organotypic culture conditions, we observed more profound effects. CatCLef-expressing cells were more proliferative, developed a thicker epithelium, and upregulated Notch signaling and several BE markers including NHE2. Cox2 expression also increased cell proliferation and induced a thicker epithelium. More importantly, we observed cysts form within the epithelium, filled with intestinal mucins including Muc5B and Muc17. This suggests that Cox2 expression in a three-dimensional culture environment induces a lineage of mucin-secreting cells and supports an important causal role for Cox2 in BE pathogenesis. We conclude that in vitro modeling of BE pathogenesis can be improved by enhancing Wnt signaling and Cox2 activity and using three-dimensional organotypic culture conditions.

Cyclooxygenase 1 (COX1 expression in Type 2 diabetes mellitus: A preliminary study from north India

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Sushma Verma

2016-01-01

Conclusion: Although COX1 is known to be a “housekeeping” gene, our study showed that its expression can be correlated with the disease condition and be used as a marker. However, further studies are required in more number of samples from other ethnic populations to confirm the findings.

Peroxisome Proliferator-Activated Receptor-α Activation Decreases Mean Arterial Pressure, Plasma Interleukin-6, and COX-2 While Increasing Renal CYP4A Expression in an Acute Model of DOCA-Salt Hypertension

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Dexter L. Lee

2011-01-01

Full Text Available Peroxisome proliferator-activated receptor-alpha (PPAR-α activation by fenofibrate reduces blood pressure and sodium retention during DOCA-salt hypertension. PPAR-α activation reduces the expression of inflammatory cytokines, such as interleukin-6 (IL-6. Fenofibrate also induces cytochrome P450 4A (CYP4A and increases 20-hydroxyeicosatetraenoic acid (20-HETE production. This study tested whether the administration of fenofibrate would reduce blood pressure by attenuating plasma IL-6 and renal expression of cyclooxygenase-2 (COX-2, while increasing expression of renal CYP4A during 7 days of DOCA-salt hypertension. We performed uni-nephrectomy on 12–14 week old male Swiss Webster mice and implanted biotelemetry devices in control, DOCA-salt (1.5 mg/g treated mice with or without fenofibrate (500 mg/kg/day in corn oil, intragastrically. Fenofibrate significantly decreased mean arterial pressure and plasma IL-6. In kidney homogenates, fenofibrate increased CYP4A and decreased COX-2 expression. There were no differences in renal cytochrome P450, family 2, subfamily c, polypeptide 23 (CYP2C23 and soluble expoxide hydrolase (sEH expression between the groups. Our results suggest that the blood pressure lowering effect of PPAR-α activation by fenofibrate involves the reduction of plasma IL-6 and COX-2, while increasing CYP4A expression during DOCA-salt hypertension. Our results may also suggest that PPAR-α activation protects the kidney against renal injury via decreased COX-2 expression.

Involvement of nitrergic system in anticonvulsant effect of zolpidem in lithium-pilocarpine induced status epilepticus: Evaluation of iNOS and COX-2 genes expression.

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Eslami, Seyyed Majid; Ghasemi, Maryam; Bahremand, Taraneh; Momeny, Majid; Gholami, Mahdi; Sharifzadeh, Mohammad; Dehpour, Ahmad Reza

2017-11-15

This study aims to investigate the role of zolpidem in lithium-pilocarpine induced status epilepticus (SE) and probable mechanisms involved in seizure threshold alteration. In the present study, lithium chloride (127mg/kg) was administered 20h prior to pilocarpine (60mg/kg) to induce SE in adult male Wistar rats. Different doses of zolpidem (0.1, 1, 2, 5, 10mg/kg) were injected 30min before pilocarpine administration. Furthermore, to find out whether nitric oxide (NO) plays a role in the observed effect, L-arginine and L-NAME were injected 15min before zolpidem. Afterward, we identified the particular NO isoform mediating the effect of zolpidem by injecting aminoguanidine (AG) and 7-Nitroindazole (7-NI) 15min prior to zolpidem. Moreover, in both 6 and 24h after pilocarpine injection, experimental groups underwent hippocampectomy to evaluate cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) genes expression by quantitative reverse transcription-PCR (qRT-PCR). Pre-treatment with zolpidem significantly prevented the onset of SE in a dose-dependent manner. AG and L-NAME significantly potentiated the anticonvulsant effect of zolpidem while L-arginine inverted this effect. Our qRT-PCR exerted that there was a continuous elevation of iNOS and COX-2 genes expression over 6 and 24h after pilocarpine administration in SE and L-arginine+Zolpidem groups while in AG/L-NAME+Zolpidem and zolpidem groups this upregulation was prevented. Our study indicates that zolpidem prevents the onset of SE through inhibition of iNOS/COX-2 genes upregulation following lithium-pilocarpine administration. Consistent with our results, we suggest that iNOS activation could be probably upstream of COX-2 gene expression. Copyright © 2017 Elsevier B.V. All rights reserved.

Stromal COX-2 signaling activated by deoxycholic acid mediates proliferation and invasiveness of colorectal epithelial cancer cells

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Zhu, Yingting, E-mail: yitizhu@yahoo.com [Arizona Cancer Center, The University of Arizona, Tucson, AZ 85724 (United States); Tissue Tech Inc., Miami, FL 33173 (United States); Zhu, Min; Lance, Peter [Arizona Cancer Center, The University of Arizona, Tucson, AZ 85724 (United States)

2012-08-31

Highlights: Black-Right-Pointing-Pointer Human colonic cancer associated fibroblasts are major sources of COX-2 and PGE{sub 2}. Black-Right-Pointing-Pointer The fibroblasts interact with human colonic epithelial cancer cells. Black-Right-Pointing-Pointer Activation of COX-2 signaling in the fibroblasts affects behavior of the epithelia. Black-Right-Pointing-Pointer Protein Kinase C controls the activation of COX-2 signaling. -- Abstract: COX-2 is a major regulator implicated in colonic cancer. However, how COX-2 signaling affects colonic carcinogenesis at cellular level is not clear. In this article, we investigated whether activation of COX-2 signaling by deoxycholic acid (DCA) in primary human normal and cancer associated fibroblasts play a significant role in regulation of proliferation and invasiveness of colonic epithelial cancer cells. Our results demonstrated while COX-2 signaling can be activated by DCA in both normal and cancer associated fibroblasts, the level of activation of COX-2 signaling is significantly greater in cancer associated fibroblasts than that in normal fibroblasts. In addition, we discovered that the proliferative and invasive potential of colonic epithelial cancer cells were much greater when the cells were co-cultured with cancer associated fibroblasts pre-treated with DCA than with normal fibroblasts pre-treated with DCA. Moreover, COX-2 siRNA attenuated the proliferative and invasive effect of both normal and cancer associate fibroblasts pre-treated with DCA on the colonic cancer cells. Further studies indicated that the activation of COX-2 signaling by DCA is through protein kinase C signaling. We speculate that activation of COX-2 signaling especially in cancer associated fibroblasts promotes progression of colonic cancer.

COX-2 and PPAR-γ confer cannabidiol-induced apoptosis of human lung cancer cells.

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Ramer, Robert; Heinemann, Katharina; Merkord, Jutta; Rohde, Helga; Salamon, Achim; Linnebacher, Michael; Hinz, Burkhard

2013-01-01

The antitumorigenic mechanism of cannabidiol is still controversial. This study investigates the role of COX-2 and PPAR-γ in cannabidiol's proapoptotic and tumor-regressive action. In lung cancer cell lines (A549, H460) and primary cells from a patient with lung cancer, cannabidiol elicited decreased viability associated with apoptosis. Apoptotic cell death by cannabidiol was suppressed by NS-398 (COX-2 inhibitor), GW9662 (PPAR-γ antagonist), and siRNA targeting COX-2 and PPAR-γ. Cannabidiol-induced apoptosis was paralleled by upregulation of COX-2 and PPAR-γ mRNA and protein expression with a maximum induction of COX-2 mRNA after 8 hours and continuous increases of PPAR-γ mRNA when compared with vehicle. In response to cannabidiol, tumor cell lines exhibited increased levels of COX-2-dependent prostaglandins (PG) among which PGD(2) and 15-deoxy-Δ(12,14)-PGJ(2) (15d-PGJ(2)) caused a translocation of PPAR-γ to the nucleus and induced a PPAR-γ-dependent apoptotic cell death. Moreover, in A549-xenografted nude mice, cannabidiol caused upregulation of COX-2 and PPAR-γ in tumor tissue and tumor regression that was reversible by GW9662. Together, our data show a novel proapoptotic mechanism of cannabidiol involving initial upregulation of COX-2 and PPAR-γ and a subsequent nuclear translocation of PPAR-γ by COX-2-dependent PGs.

Optimization of a nonviral transfection system to evaluate Cox-2 controlled interleukin-4 expression for osteoarthritis gene therapy in vitro.

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Lang, Annemarie; Neuhaus, Johannes; Pfeiffenberger, Moritz; Schröder, Erik; Ponomarev, Igor; Weber, Yvonne; Gaber, Timo; Schmidt, Michael F G

2014-01-01

Gene therapy appears to have the potential for achieving a long-term remedy for osteoarthritis (OA). However, there is a risk of adverse reactions, especially when using cytomegalovirus-controlled expression. To provide a safe application, we focused on the expression of therapeutic cytokines [e.g. interleukin (IL)-4] in a disease-responsive manner by use of the previously cloned Cox-2 promoter as 'genetic switch'. In the present study, we report the functionality of a controlled gene therapeutic system in an equine osteoarthritic cell model. Different nonviral transfection reagents were tested for their efficiency on equine chondrocytes stimulated with equine IL-1β or lipopolysaccharide to create an inflammatory environment. To optimize the transfection, we successfully redesigned the vector by excluding the internal ribosomal entry site (IRES). The functionality of our Cox-2 promoter construct with respect to expressing IL-4 was proven at the mRNA and protein levels and the anti-inflammatory potential of IL-4 was confirmed by analyzing the expression of IL-1β, IL-6, IL-8, matrix metalloproteinase (MMP)-1, MMP-3 and tumor necrosis factor (TNF)-α using a quantitative polymerase chain reaction. Nonviral transfection reagents yielded transfection rates from 21% to 44% with control vectors with and without IRES, respectively. Stimulation of equine chondrocytes resulted in a 20-fold increase of mRNA expression of IL-1β. Such exogenous stimulation of chondrocytes transfected with pNCox2-IL4 led to an increase of IL-4 mRNA expression, whereas expression of inflammatory mediators decreased. The timely link between these events confirms the anti-inflammatory potential of synthesized IL-4. We consider that this approach has significant potential for translation into a useful anti-inflammation therapy. Molecular tools such as the described therapeutic plasmid pave the way for a local-controlled, self-limiting gene therapy. Copyright © 2014 John Wiley & Sons, Ltd.

The Differential Impact of High-Intensity Swimming Exercise and Inflammatory Bowel Disease on IL-1β, TNF-α, and COX-2 Gene Expression in the Small Intestine and Colon in Mice

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Eun-Ju Choi

2018-04-01

Full Text Available Background and Objective: We aimed to examine the impact of high-intensity swimming exercise and inflammatory bowel disease (IBD on IL-1β, TNF-α, and COX-2 gene expression in the small intestine and colon of mice. Material and Methods: Forty male C57BL/6 mice were divided into 4 groups: the control group (CON, swimming exercise group (EX, 50% ethanol (EtoH control group (50%EtoH CON, and 2,4,6-trinitrobenzene sulfonic acid group (TNBS. The EX group performed 4 weeks of exercise. Intrarectal TNBS injection induced IBD in the TNBS group; the 50%EtoH CON group received control injections. Reverse transcription and real-time polymerase chain reaction were used to examine IL-1β, TNF-α, and COX-2 mRNA expression in the small intestine and colon. Results: IL-1β, TNF-α, and COX-2 mRNA expression was significantly increased in the EX group compared to that in the CON group (p’s<0.05. IL-1β and COX-2 mRNA expression was significantly increased in the TNBS group compared to that in the 50%EtoH CON group (p’s<0.05. Conclusion: Thus, inflammatory cytokine IL-1β and COX-2 expression in the small intestine and colon was increased in both high-intensity swimming exercise and IBD models. However, TNF-α was increased only in the swimming exercise model. Further research is required to confirm these observations and establish swimming exercise regimes appropriate for patients with IBD.

Δ9-THC-caused synaptic and memory impairments are mediated through COX-2 signaling

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Yang, Hongwei; Tang, Ya-ping; Sun, Hao; Song, Yunping; Chen, Chu

2013-01-01

SUMMARY Marijuana has been used for thousands of years as a treatment for medical conditions. However, untoward side effects limit its medical value. Here we show that synaptic and cognitive impairments following repeated exposure to Δ9-tetrahydrocannabinol (Δ9-THC) are associated with the induction of cyclooxygenase-2 (COX-2), an inducible enzyme that converts arachidonic acid to prostanoids, in the brain. COX-2 induction by Δ9-THC is mediated via CB1 receptor-coupled G-protein βγ subunits. Pharmacological or genetic inhibition of COX-2 blocks down-regulation and internalization of glutamate receptor subunits and alterations of the dendritic spine density of hippocampal neurons induced by repeated Δ9-THC exposures. Ablation of COX-2 also eliminates Δ9-THC-impaired hippocampal long-term synaptic plasticity, spatial, and fear memories. Importantly, the beneficial effects of decreasing β-amyloid plaques and neurodegeneration by Δ9-THC in Alzheimer’s disease animals are retained in the presence of COX-2 inhibition. These results suggest that the applicability of medical marijuana would be broadened by concurrent inhibition of COX-2. PMID:24267894

A high-fat diet activates oncogenic Kras and COX2 to induce development of pancreatic ductal adenocarcinoma in mice.

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Philip, Bincy; Roland, Christina L; Daniluk, Jaroslaw; Liu, Yan; Chatterjee, Deyali; Gomez, Sobeyda B; Ji, Baoan; Huang, Haojie; Wang, Huamin; Fleming, Jason B; Logsdon, Craig D; Cruz-Monserrate, Zobeida

2013-12-01

Obesity is a risk factor for pancreatic ductal adenocarcinoma (PDAC), but it is not clear how obesity contributes to pancreatic carcinogenesis. The oncogenic form of KRAS is expressed during early stages of PDAC development and is detected in almost all of these tumors. However, there is evidence that mutant KRAS requires an additional stimulus to activate its full oncogenic activity and that this stimulus involves the inflammatory response. We investigated whether the inflammation induced by a high-fat diet, and the accompanying up-regulation of cyclooxygenase-2 (COX2), increases Kras activity during pancreatic carcinogenesis in mice. We studied mice with acinar cell-specific expression of KrasG12D (LSL-Kras/Ela-CreERT mice) alone or crossed with COX2 conditional knockout mice (COXKO/LSL-Kras/Ela-CreERT). We also studied LSL-Kras/PDX1-Cre mice. All mice were fed isocaloric diets with different amounts of fat, and a COX2 inhibitor was administered to some LSL-Kras/Ela-CreERT mice. Pancreata were collected from mice and analyzed for Kras activity, levels of phosphorylated extracellular-regulated kinase, inflammation, fibrosis, pancreatic intraepithelial neoplasia (PanIN), and PDACs. Pancreatic tissues from LSL-Kras/Ela-CreERT mice fed high-fat diets (HFDs) had increased Kras activity, fibrotic stroma, and numbers of PanINs and PDACs than LSL-Kras/Ela-CreERT mice fed control diets; the mice fed the HFDs also had shorter survival times than mice fed control diets. Administration of a COX2 inhibitor to LSL-Kras/Ela-CreERT mice prevented these effects of HFDs. We also observed a significant reduction in survival times of mice fed HFDs. COXKO/LSL-Kras/Ela-CreERT mice fed HFDs had no evidence for increased numbers of PanIN lesions, inflammation, or fibrosis, as opposed to the increases observed in LSL-Kras/Ela-CreERT mice fed HFDs. In mice, an HFD can activate oncogenic Kras via COX2, leading to pancreatic inflammation and fibrosis and development of PanINs and PDAC. This

The Effect of Bee Venom on COX-2, P38, ERK and JNK in RAW 264.7 Cells

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Jae-Young Sim

2003-06-01

Full Text Available Objectives : The purpose of this study was to investigate the effect of Bee Venom on the lipopolysaccharide(LPS, sodium nitroprusside(SNP, hydrogen peroxide(H2O2-induced expressions of cyclooxygenase-2(COX-2, p38, jun N-terminal Kinase(JNK and extra-signal response kinase(ERK in RAW 264.7 cells, a murine macrophage cell line. Methods : The expressions of COX-2, p38, JNK and ERK were determined by western blotting with corresponding antibodies.\\ Results : 1. The 0.5, 1 and 5 ㎍/㎖ of bee venom inhibited significantly LPS and SNP-induced expression of COX-2 compared with control, respectively. The 0.5, 1 and 5 ㎍/㎖ of bee venom inhibited insignificantly H2O2-induced expression of COX-2 compared with control, respectively. 2. The 0.5, 1 and 5 ㎍/㎖ of bee venom inhibited significantly LPS, SNP and H2O2-induced expression of p38 compared with control, respectively. 3. The 1 and 5 ㎍/㎖ of bee venom inhibited significantly SNP-induced expression of JNK compared with control, respectively. All of bee venom inhibited insignificantly LPS and H2O2-induced expression of JNK compared with control, respectively. 4. The 5 ㎍/㎖ of bee venom inhibited significantly SNP-induced expression of ERK, the 0.5 ㎍/㎖ of bee venom increased significantly H2O2-induced expression of ERK compared with control. The 0.5, 1 and 5 ㎍/㎖ of bee venom inhibited insignificantly LPS-induced expression of ERK compared with control, respectively.

Bcr-Abl-independent mechanism of resistance to imatinib in K562 cells: Induction of cyclooxygenase-2 (COX-2) by histone deacetylases (HDACs).

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Kalle, Arunasree M; Sachchidanand, Sachchidanand; Pallu, Reddanna

2010-09-01

Our previous studies have shown that overexpression of MDR1 and cyclooygenase-2 (COX-2) resulted in resistance development to imatinib in chronic myelogenous leukemia (CML) K562 (IR-K562) cells. In the present study, the regulatory mechanism of MDR1 induction by COX-2 was investigated. A gradual overexpression of MDR1 and COX-2 during the process of development was observed. Furthermore, down regulation of MDR1 upon COX-2 knockdown by siRNA showed a decrease in the PKC levels and activation of PKC by addition of PGE(2) to K562 cells, suggesting a role for PKC in the COX-2 mediated induction of MDR1. The present study demonstrates COX-2 induction by HDACs and MDR1 induction by COX-2 via PGE(2)-cAMP-PKC-mediated pathway. Copyright 2010 Elsevier Ltd. All rights reserved.

Neoplasms escape selective COX-2 inhibition in an animal model of breast cancer.

LENUS (Irish Health Repository)

Barry, M

2009-06-01

Cyclo-oxygenase-2 (COX-2) is up-regulated in malignant tumours rendering it an attractive target for cancer therapeutics. However, whether long-term antagonism maintains its initial efficacy on established tumours is unclear.

Feedback amplification of fibrosis through matrix stiffening and COX-2 suppression

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Liu, Fei; Mih, Justin D.; Shea, Barry S.; Kho, Alvin T.; Sharif, Asma S.; Tager, Andrew M.

2010-01-01

Tissue stiffening is a hallmark of fibrotic disorders but has traditionally been regarded as an outcome of fibrosis, not a contributing factor to pathogenesis. In this study, we show that fibrosis induced by bleomycin injury in the murine lung locally increases median tissue stiffness sixfold relative to normal lung parenchyma. Across this pathophysiological stiffness range, cultured lung fibroblasts transition from a surprisingly quiescent state to progressive increases in proliferation and matrix synthesis, accompanied by coordinated decreases in matrix proteolytic gene expression. Increasing matrix stiffness strongly suppresses fibroblast expression of COX-2 (cyclooxygenase-2) and synthesis of prostaglandin E2 (PGE2), an autocrine inhibitor of fibrogenesis. Exogenous PGE2 or an agonist of the prostanoid EP2 receptor completely counteracts the proliferative and matrix synthetic effects caused by increased stiffness. Together, these results demonstrate a dominant role for normal tissue compliance, acting in part through autocrine PGE2, in maintaining fibroblast quiescence and reveal a feedback relationship between matrix stiffening, COX-2 suppression, and fibroblast activation that promotes and amplifies progressive fibrosis. PMID:20733059

Pharmacologic inhibition of COX-1 and COX-2 in influenza A viral infection in mice.

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Michelle A Carey

Full Text Available BACKGROUND: We previously demonstrated that cyclooxygenase (COX-1 deficiency results in greater morbidity and inflammation, whereas COX-2 deficiency leads to reduced morbidity, inflammation and mortality in influenza infected mice. METHODOLOGY/PRINCIPAL FINDINGS: We investigated the effects of COX-1 and COX-2 inhibitors in influenza A viral infection. Mice were given a COX-1 inhibitor (SC-560, a COX-2 inhibitor (celecoxib or no inhibitor beginning 2 weeks prior to influenza A viral infection (200 PFU and throughout the course of the experiment. Body weight and temperature were measured daily as indicators of morbidity. Animals were sacrificed on days 1 and 4 post-infection and bronchoalveolar lavage (BAL fluid was collected or daily mortality was recorded up to 2 weeks post-infection. Treatment with SC-560 significantly increased mortality and was associated with profound hypothermia and greater weight loss compared to celecoxib or control groups. On day 4 of infection, BAL fluid cells were modestly elevated in celecoxib treated mice compared to SC-560 or control groups. Viral titres were similar between treatment groups. Levels of TNF-alpha and G-CSF were significantly attenuated in the SC-560 and celecoxib groups versus control and IL-6 levels were significantly lower in BAL fluid of celecoxib treated mice versus control and versus the SC-560 group. The chemokine KC was significantly lower in SC-560 group versus control. CONCLUSIONS/SIGNIFICANCE: Treatment with a COX-1 inhibitor during influenza A viral infection is detrimental to the host whereas inhibition of COX-2 does not significantly modulate disease severity. COX-1 plays a critical role in controlling the thermoregulatory response to influenza A viral infection in mice.

Long non-coding RNA cox-2 prevents immune evasion and metastasis of hepatocellular carcinoma by altering M1/M2 macrophage polarization.

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Ye, Yibiao; Xu, Yunxiuxiu; Lai, Yu; He, Wenguang; Li, Yanshan; Wang, Ruomei; Luo, Xinxi; Chen, Rufu; Chen, Tao

2018-03-01

Macrophages have been shown to demonstrate a high level of plasticity, with the ability to undergo dynamic transition between M1 and M2 polarized phenotypes. We investigate long non-coding RNA (lncRNA) cox-2 in macrophage polarization and the regulatory mechanism functions in hepatocellular carcinoma (HCC). Lipopolysaccharide (LPS) was used to induce RAW264.7 macrophages into M1 type, and IL-4 was to induce RAW264.7 macrophages into M2 type. We selected mouse hepatic cell line Hepal-6 and hepatoma cell line HepG2 for co-incubation with M1 or M2 macrophages. Quantitative real-time PCR was used to detect the expressions of lncRNA cox-2 and mRNAs. ELISA was conducted for testing IL-12 and IL-10 expressions; Western blotting for epithelial mesenchymal transition related factors (E-cadherin and Vimentin). An MTT, colony formation assay, flow cytometry, transwell assay, and stretch test were conducted to test cell abilities. The M1 macrophages had higher lncRNA cox-2 expression than that in the non-polarized macrophages and M2 macrophages. The lncRNA cox-2 siRNA decreased the expression levels of IL-12, iNOS, and TNF-α in M1 macrophages, increased the expression levels of IL-10, Arg-1, and Fizz-1 in M2 macrophages (all P evasion and tumor growth by inhibiting the polarization of M2 macrophages. © 2017 Wiley Periodicals, Inc.

Angiopoietin-2 regulates gene expression in TIE2-expressing monocytes and augments their inherent proangiogenic functions.

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Coffelt, Seth B; Tal, Andrea O; Scholz, Alexander; De Palma, Michele; Patel, Sunil; Urbich, Carmen; Biswas, Subhra K; Murdoch, Craig; Plate, Karl H; Reiss, Yvonne; Lewis, Claire E

2010-07-01

TIE2-expressing monocytes/macrophages (TEM) are a highly proangiogenic subset of myeloid cells in tumors. Here, we show that circulating human TEMs are already preprogrammed in the circulation to be more angiogenic and express higher levels of such proangiogenic genes as matrix metalloproteinase-9 (MMP-9), VEGFA, COX-2, and WNT5A than TIE2(-) monocytes. Additionally, angiopoietin-2 (ANG-2) markedly enhanced the proangiogenic activity of TEMs and increased their expression of two proangiogenic enzymes: thymidine phosphorylase (TP) and cathepsin B (CTSB). Three "alternatively activated" (or M2-like) macrophage markers were also upregulated by ANG-2 in TEMs: interleukin-10, mannose receptor (MRC1), and CCL17. To investigate the effects of ANG-2 on the phenotype and function of TEMs in tumors, we used a double-transgenic (DT) mouse model in which ANG-2 was specifically overexpressed by endothelial cells. Syngeneic tumors grown in these ANG-2 DT mice were more vascularized and contained greater numbers of TEMs than those in wild-type (WT) mice. In both tumor types, expression of MMP-9 and MRC1 was mainly restricted to tumor TEMs rather than TIE2(-) macrophages. Furthermore, tumor TEMs expressed higher levels of MRC1, TP, and CTSB in ANG-2 DT tumors than WT tumors. Taken together, our data show that although circulating TEMs are innately proangiogenic, exposure to tumor-derived ANG-2 stimulates these cells to exhibit a broader, tumor-promoting phenotype. As such, the ANG-2-TEM axis may represent a new target for antiangiogenic cancer therapies. Copyright 2010 AACR.

Nano-gold displayed anti-inflammatory property via NF-kB pathways by suppressing COX-2 activity.

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Khan, Mahmood Ahmad; Khan, Mohd Jahir

2018-03-19

Rheumatoid arthritis (RA) is an autoimmune inflammatory disease, affecting almost 1% of world population. Although the exact cause of RA is not known but the complex interaction between inflammatory mediators like tumour necrosis factor-α (TNF-α), interleukin-1β (IL-1β), cyclooxygenase-2 (COX-2) and nitric oxide (NO) is accountable for cartilage destruction in joints. Gold is used for arthritis treatment since long without knowing its mechanism of action. Hence, the present study was designed to assess antiarthritic activity of nanogold (AuNGs) in collagen-induced arthritic (CIA) rat model by virtue of decreasing inflammatory mediators and oxidative stress. After induction CIA rats were treated with AuNGs in phosphate buffer at a dose of 20 μg/kg body weight for 20 days and found a significant decrease in the level of inflammatory mediators like TNF-α, IL-1β, COX-2 and transcription factor NF-kB (Nuclear factor-kB), which was found to be elevated in CIA rats. Additionally imbalance in oxidant and antioxidant status were determined and perceived that AuNGs remarkably attenuates the imbalance in level of antioxidant and oxidant near to normal. In consistent to biochemical results, mRNA expression of NF-kB, TNF-α, COX-2, and iNOS were also up-regulated in CIA rats, which were considerably down regulated by AuNGs treatment. These findings were positively correlated with the histological results of joints, displayed reduced inflammation and bone erosion in treated group. This study demonstrates the ability of AuNGs to ameliorate production of inflammatory mediators and oxidative stress in CIA rats. Induction of arthritis in rats showed increased inflammation, which activate the transcription factor NF-kB through activation of of IkB kinases (IKK) and ubiquination/proteosome degradation of IKB and transportation of activated NF-kB from cytoplasm to nucleus. In nucleus activated NF-kB bind to the promoter region of target gene and up regulate the production of

Celecoxib Alleviates Memory Deficits by Downregulation of COX-2 Expression and Upregulation of the BDNF-TrkB Signaling Pathway in a Diabetic Rat Model.

Science.gov (United States)

Yang, Ying; Gao, Ling

2017-06-01

Previous studies conveyed that diabetes causes learning and memory deficits. Data also suggest that celecoxib exerts an anti-hyperalgesic, anti-allodynic, and a plethora of other beneficial effects in diabetic rats. However, whether celecoxib could alleviate memory deficit in diabetic rat is unknown. In the present study, we aimed to examine the potential of celecoxib to counter memory deficits in diabetes. Experimental diabetes was induced by streptozotocin (STZ, 60 mg/kg) in male SD rats. Rats were divided into three groups (n = 16/group): normal control group injected with normal saline, diabetes group injected with STZ, and diabetes + celecoxib group in which diabetic rats were administered with celecoxib by gavage in drinking water (10 mg/kg) for 10 days in terms of which memory performance in animals was measured, hippocampal tissue harvested, and long-term potentiation assessed. Western blotting and immunohistochemical staining were performed to determine cyclooxygenase 2 (COX-2) expression in hippocampus. The results showed that a rat model of STZ-induced diabetes was successfully established and that celecoxib treatment significantly improved the associated nephropathy and inflammation. Moreover, spatial memory and hippocampal long-term potentiation (LTP) were impaired in diabetic model (P memory deficit and hippocampal LTP in the diabetic rats. To understand the underlying mechanisms, the expression of some important pathways involved in memory impairment was determined. We found that brain-derived neurotrophic factor (BDNF) and phosphorylated tropomyosin-related kinase (p-TrkB) were decreased in diabetic rats but were effectively reversed by celecoxib treatment. As evidenced by western blotting and immunohistochemical staining, the expression of COX-2 in hippocampus was significantly upregulated in diabetic rat (P memory deficits via probable downregulation of hippocampal COX-2 expression and upregulation of the BDNF-TrkB signaling pathway in a

Licochalcone A, a Polyphenol Present in Licorice, Suppresses UV-Induced COX-2 Expression by Targeting PI3K, MEK1, and B-Raf

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Nu Ry Song

2015-02-01

Full Text Available Licorice is a traditional botanical medicine, and has historically been commonly prescribed in Asia to treat various diseases. Glycyrrhizin (Gc, a triterpene compound, is the most abundant phytochemical constituent of licorice. However, high intake or long-term consumption of Gc has been associated with a number of side effects, including hypertension. However, the presence of alternative bioactive compounds in licorice with anti-carcinogenic effects has long been suspected. Licochalcone A (LicoA is a prominent member of the chalcone family and can be isolated from licorice root. To date, there have been no reported studies on the suppressive effect of LicoA against solar ultraviolet (sUV-induced cyclooxygenase (COX-2 expression and the potential molecular mechanisms involved. Here, we show that LicoA, a major chalcone compound of licorice, effectively inhibits sUV-induced COX-2 expression and prostaglandin E2 PGE2 generation through the inhibition of activator protein 1 AP-1 transcriptional activity, with an effect that is notably more potent than Gc. Western blotting analysis shows that LicoA suppresses sUV-induced phosphorylation of Akt/ mammalian target of rapamycin (mTOR and extracellular signal-regulated kinases (ERK1/2/p90 ribosomal protein S6 kinase (RSK in HaCaT cells. Moreover, LicoA directly suppresses the activity of phosphoinositide 3-kinase (PI3K, mitogen-activated protein kinase kinase (MEK1, and B-Raf, but not Raf-1 in cell-free assays, indicating that PI3K, MEK1, and B-Raf are direct molecular targets of LicoA. We also found that LicoA binds to PI3K and B-Raf in an ATP-competitive manner, although LicoA does not appear to compete with ATP for binding with MEK1. Collectively, these results provide insight into the biological action of LicoA, which may have potential for development as a skin cancer chemopreventive agent.

Protein kinase A antagonist inhibits β-catenin nuclear translocation, c-Myc and COX-2 expression and tumor promotion in ApcMin/+ mice

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Brudvik Kristoffer W

2011-12-01

Full Text Available Abstract Background The adenomatous polyposis coli (APC protein is part of the destruction complex controlling proteosomal degradation of β-catenin and limiting its nuclear translocation, which is thought to play a gate-keeping role in colorectal cancer. The destruction complex is inhibited by Wnt-Frz and prostaglandin E2 (PGE2 - PI-3 kinase pathways. Recent reports show that PGE2-induced phosphorylation of β-catenin by protein kinase A (PKA increases nuclear translocation indicating two mechanisms of action of PGE2 on β-catenin homeostasis. Findings Treatment of ApcMin/+ mice that spontaneously develop intestinal adenomas with a PKA antagonist (Rp-8-Br-cAMPS selectively targeting only the latter pathway reduced tumor load, but not the number of adenomas. Immunohistochemical characterization of intestines from treated and control animals revealed that expression of β-catenin, β-catenin nuclear translocation and expression of the β-catenin target genes c-Myc and COX-2 were significantly down-regulated upon Rp-8-Br-cAMPS treatment. Parallel experiments in a human colon cancer cell line (HCT116 revealed that Rp-8-Br-cAMPS blocked PGE2-induced β-catenin phosphorylation and c-Myc upregulation. Conclusion Based on our findings we suggest that PGE2 act through PKA to promote β-catenin nuclear translocation and tumor development in ApcMin/+ mice in vivo, indicating that the direct regulatory effect of PKA on β-catenin nuclear translocation is operative in intestinal cancer.

COX-2, VEGF and tumour angiogenesis.

LENUS (Irish Health Repository)

Toomey, D P

2009-06-01

Epidemiological evidence suggests a protective effective of regular NSAID use against developing cancer. Cyclooxygenase-2, a target of NSAIDs, is upregulated in many cancers and has been associated with increased VEGF production and angiogenesis. Angiogenesis is the formation of new vessels from existing vasculature and as an essential process for tumour development represents an important therapeutic target. Following an extensive review of the literature this article details the current knowledge on the role of COX-2 in tumorigenesis focusing on its relationship to angiogenesis and VEGF production by tumour cells. While COX-2 is clearly detrimental to prognosis and NSAIDs have a beneficial effect, the possibility of COX-2 independent effects being partly or wholly responsible for this benefit cannot be excluded.

Relationship between serum levels of triglycerides and vascular inflammation, measured as COX-2, in arteries from diabetic patients: a translational study

Science.gov (United States)

2013-01-01

Background Inflammation is a common feature in the majority of cardiovascular disease, including Diabetes Mellitus (DM). Levels of pro-inflammatory markers have been found in increasing levels in serum from diabetic patients (DP). Moreover, levels of Cyclooxygenase-2 (COX-2) are increased in coronary arteries from DP. Methods Through a cross-sectional design, patients who underwent CABG were recruited. Vascular smooth muscle cells (VSMC) were cultured and COX-2 was measured by western blot. Biochemical and clinical data were collected from the medical record and by blood testing. COX-2 expression was analyzed in internal mammary artery cross-sections by confocal microscopy. Eventually, PGI2 and PGE2 were assessed from VSMC conditioned media by ELISA. Results Only a high glucose concentration, but a physiological concentration of triglycerides exposure of cultured human VSMC derived from non-diabetic patients increased COX-2 expression .Diabetic patients showed increasing serum levels of glucose, Hb1ac and triglycerides. The bivariate analysis of the variables showed that triglycerides was positively correlated with the expression of COX-2 in internal mammary arteries from patients (r2 = 0.214, P < 0.04). Conclusions We conclude that is not the glucose blood levels but the triglicerydes leves what increases the expression of COX-2 in arteries from DP. PMID:23642086

Radioprotection of intestinal crypt cells by cox-inhibitors

International Nuclear Information System (INIS)

Bisnar, Paul O.; Dones, Rosa Angela S.A.; Serna, Paulene-Ver A.; Deocaris, Chester C.; Guttierez, Kalangitan V.; Deocaris, Custer C.

2006-01-01

The regulation of tissue homeostasis in the gastrointestinal epithelium after epithelial injury focuses on the prostaglandins(PGs) as its major mediators. The two cyclooxygenase isoforms, cox-1 and cox-2, catalyze synthesis of PGs. Cox-1 is the predominant cyclooxygenase isoform found in the normal intestine. In contrast, cox-2 is present at low levels in normal intestine but is elevated at sites of inflammation, and in adenomas and carcinomas. To study the effects of various commercially-available cox-inhibitors (Ketorolac: cox-1 selective; Celecoxib: cox-2 selective; and Indocid: cox-1/2 non-selective), we determine mouse crypt epithelial cell fate after genotoxic injury with whole-body gamma-ray exposure at 15 Gy. Intestinal tissues of mice treated with cox-2 inhibitors that showed invariable apoptotic event, however, have increased occurrence of regenerating cells. Our results suggest a potential application of cox-2 selective inhibitors as radioprotective agent for normal cells after radiotherapy. (Author)

Increased cyclooxygenase 2 expression in association with oral lichen planus severity

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Thaneeya Chankong

2016-09-01

Conclusion: Enhanced COX-2 expression in both OLP epithelium and inflammatory infiltrates correlates well with the clinical severity. An association between VAS score and COX-2 expression in OLP inflammatory infiltrates suggests an important role of additional COX-2 expression from inflammation in causing pain in OLP patients.

Extracellular histones disarrange vasoactive mediators release through a COX-NOS interaction in human endothelial cells.

Science.gov (United States)

Pérez-Cremades, Daniel; Bueno-Betí, Carlos; García-Giménez, José Luis; Ibañez-Cabellos, José Santiago; Hermenegildo, Carlos; Pallardó, Federico V; Novella, Susana

2017-08-01

Extracellular histones are mediators of inflammation, tissue injury and organ dysfunction. Interactions between circulating histones and vascular endothelial cells are key events in histone-mediated pathologies. Our aim was to investigate the implication of extracellular histones in the production of the major vasoactive compounds released by human endothelial cells (HUVECs), prostanoids and nitric oxide (NO). HUVEC exposed to increasing concentrations of histones (0.001 to 100 μg/ml) for 4 hrs induced prostacyclin (PGI2) production in a dose-dependent manner and decreased thromboxane A2 (TXA2) release at 100 μg/ml. Extracellular histones raised cyclooxygenase-2 (COX-2) and prostacyclin synthase (PGIS) mRNA and protein expression, decreased COX-1 mRNA levels and did not change thromboxane A2 synthase (TXAS) expression. Moreover, extracellular histones decreased both, eNOS expression and NO production in HUVEC. The impaired NO production was related to COX-2 activity and superoxide production since was reversed after celecoxib (10 μmol/l) and tempol (100 μmol/l) treatments, respectively. In conclusion, our findings suggest that extracellular histones stimulate the release of endothelial-dependent mediators through an up-regulation in COX-2-PGIS-PGI2 pathway which involves a COX-2-dependent superoxide production that decreases the activity of eNOS and the NO production. These effects may contribute to the endothelial cell dysfunction observed in histone-mediated pathologies. © 2017 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

USP22 acts as an oncogene by regulating the stability of cyclooxygenase-2 in non-small cell lung cancer

Energy Technology Data Exchange (ETDEWEB)

Xiao, Haibo [Department of Cardiothoracic Surgery, Xinhua Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200092 (China); Tian, Yue [Institute of Orthopaedics, Chinese PLA General Hospital, Beijing 100853 (China); Yang, Yang; Hu, Fengqing; Xie, Xiao; Mei, Ju [Department of Cardiothoracic Surgery, Xinhua Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200092 (China); Ding, Fangbao, E-mail: drnail@sina.com [Department of Cardiothoracic Surgery, Xinhua Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200092 (China)

2015-05-08

The histone ubiquitin hydrolase ubiquitin-specific protease 22 (USP22) is an epigenetic modifier and an oncogene that is upregulated in many types of cancer. In non-small cell lung cancer (NSCLC), aberrant expression of USP22 is a predictor of poor survival, as is high expression of cyclooxygenase-2 (COX-2). Despite its oncogenic role, few substrates of USP22 have been identified and its mechanism of action in cancer remains unclear. Here, we identified COX-2 as a direct substrate of USP22 and showed that its levels are modulated by USP22 mediated deubiquitination. Silencing of USP22 downregulated COX-2, decreased its half-life, and inhibited lung carcinoma cell proliferation by directly interacting with and modulating the stability and activity of COX-2 through the regulation of its ubiquitination status. The findings of the present study suggest a potential mechanism underlying the oncogenic role of USP22 mediated by the modulation of the stability and activity of COX-2. - Highlights: • USP22 interacts with COX-2. • USP22 deubiquitinates and stabilizes COX-2. • USP22 is required for COX-2-mediated upregulation of prostaglandin E2.

Niacin and biosynthesis of PGD2 by platelet COX-1 in mice and humans

Science.gov (United States)

Song, Wen-Liang; Stubbe, Jane; Ricciotti, Emanuela; Alamuddin, Naji; Ibrahim, Salam; Crichton, Irene; Prempeh, Maxwell; Lawson, John A.; Wilensky, Robert L.; Rasmussen, Lars Melholt; Puré, Ellen; FitzGerald, Garret A.

2012-01-01

The clinical use of niacin to treat dyslipidemic conditions is limited by noxious side effects, most commonly facial flushing. In mice, niacin-induced flushing results from COX-1–dependent formation of PGD2 and PGE2 followed by COX-2–dependent production of PGE2. Consistent with this, niacin-induced flushing in humans is attenuated when niacin is combined with an antagonist of the PGD2 receptor DP1. NSAID-mediated suppression of COX-2–derived PGI2 has negative cardiovascular consequences, yet little is known about the cardiovascular biology of PGD2. Here, we show that PGD2 biosynthesis is augmented during platelet activation in humans and, although vascular expression of DP1 is conserved between humans and mice, platelet DP1 is not present in mice. Despite this, DP1 deletion in mice augmented aneurysm formation and the hypertensive response to Ang II and accelerated atherogenesis and thrombogenesis. Furthermore, COX inhibitors in humans, as well as platelet depletion, COX-1 knockdown, and COX-2 deletion in mice, revealed that niacin evoked platelet COX-1–derived PGD2 biosynthesis. Finally, ADP-induced spreading on fibrinogen was augmented by niacin in washed human platelets, coincident with increased thromboxane (Tx) formation. However, in platelet-rich plasma, where formation of both Tx and PGD2 was increased, spreading was not as pronounced and was inhibited by DP1 activation. Thus, PGD2, like PGI2, may function as a homeostatic response to thrombogenic and hypertensive stimuli and may have particular relevance as a constraint on platelets during niacin therapy. PMID:22406532

Resistance to ursolic acid-induced apoptosis through involvement of melanogenesis and COX-2/PGE2 pathways in human M4Beu melanoma cancer cells

International Nuclear Information System (INIS)

Hassan, Lama; Pinon, Aline; Limami, Youness; Seeman, Josiane; Fidanzi-Dugas, Chloe; Martin, Frederique; Badran, Bassam; Simon, Alain; Liagre, Bertrand

2016-01-01

Melanoma is one of the most aggressive forms of cancer with a continuously growing incidence worldwide and is usually resistant to chemotherapy agents, which is due in part to a strong resistance to apoptosis. Previously, we had showed that B16-F0 murine melanoma cells undergoing apoptosis are able to delay their own death induced by ursolic acid (UA), a natural pentacyclic triterpenoid compound. We had demonstrated that tyrosinase and TRP-1 up-regulation in apoptotic cells and the subsequent production of melanin were implicated in an apoptosis resistance mechanism. Several resistance mechanisms to apoptosis have been characterized in melanoma such as hyperactivation of DNA repair mechanisms, drug efflux systems, and reinforcement of survival signals (PI3K/Akt, NF-κB and Raf/MAPK pathways). Otherwise, other mechanisms of apoptosis resistance involving different proteins, such as cyclooxygenase-2 (COX-2), have been described in many cancer types. By using a strategy of specific inhibition of each ways, we suggested that there was an interaction between melanogenesis and COX-2/PGE 2 pathway. This was characterized by analyzing the COX-2 expression and activity, the expression of tyrosinase and melanin production. Furthermore, we showed that anti-proliferative and proapoptotic effects of UA were mediated through modulation of multiple signaling pathways including Akt and ERK-1/2 proteins. Our study not only uncovers underlying molecular mechanisms of UA action in human melanoma cancer cells but also suggest its great potential as an adjuvant in treatment and cancer prevention.

Regulation of prostaglandin E2 synthesis after brain irradiation

International Nuclear Information System (INIS)

Moore, Amy H.; Olschowka, John A.; Williams, Jacqueline P.; Okunieff, Paul; O'Banion, M. Kerry

2005-01-01

Purpose: A local tissue reaction, termed neuroinflammation, occurs after irradiation of brain tissue. Previous work suggested that cyclooxygenase (COX)-2 activity was important for changes in gene expression associated with neuroinflammation as well as increased prostaglandin E 2 (PGE 2 ) levels seen after radiation treatment. Methods and materials: To begin to determine the contributions of other enzymes involved in PGE 2 production, we examined protein levels of COX-1 and COX-2 as well as 2 PGE synthases (membrane and cytosolic PGES) 4 h after 35 Gy single dose irradiation to the brains of C3HeN mice. We also evaluated the effects of specific COX inhibitors on PGE 2 production and PGES expression. Results: As expected, COX-2 expression increased after radiation exposure. Brain irradiation also increased tissue protein levels for both PGES isoforms. Specific COX-2 inhibition with NS398 lowered brain PGE 2 levels by about 60%. Surprisingly, COX-1 inhibition with SC560 completely prevented the elevation of PGE 2 seen after irradiation. Interestingly, NS398 reduced the membrane-associated PGES isoform, whereas SC560 treatment lowered cytosolic isoform levels below those seen in unirradiated controls. Conclusions: Taken together, these data indicate that both cyclooxygenases contribute to PGE 2 production in irradiated brain and reveal dependence of PGES isoforms expression on specific cyclooxygenase activities

Cyclooxygenase 2 and neuronal nitric oxide synthase expression in the renal cortex are not interdependent in states of salt deficiency

DEFF Research Database (Denmark)

Castrop, H; Kammerl, M; Mann, Birgitte

2000-01-01

Neuronal nitric oxide synthase (nNOS) and cyclooxygenase-2 (COX-2) expression in the kidney are localized to the cortical thick ascending limb of the loop of Henle (cTALH), including the macula region, and increase after salt restriction. Because of the similar localization and regulation of n...... excretion. These findings suggest that under these conditions the control of nNOS and COX-2 gene expression in the macula densa regions of the kidney cortex are not dependent on each other....

Expressão de p53, p16 E COX-2 em carcinoma escamoso de esôfago e associação histopatológica p53, p16 E COX-2 expression in esophageal squamous cell carcinoma and histopathological association

OpenAIRE

Izabella Paz Danezi Felin; Ivana Grivicich; Carlos Roberto Felin; Andrea Regner; Adriana Brondani da Rocha

2008-01-01

RACIONAL: O câncer de esôfago representa cerca de 2% dos tumores malignos e a terceira causa mais comum de câncer do trato gastrointestinal. A associação do prognóstico do câncer de esôfago com alguns marcadores imunoistoquímicos, como as proteínas p53, p16 e a ciclooxigenase 2 (COX-2) tem sido relatada. A detecção de marcadores moleculares através de imunoistoquímica pode ser utilizada para avaliação prognóstica. OBJETIVOS: Investigar a associação entre a expressão das proteínas p53, p16 e a...

Cyclooxygenase-2 Expression in Chronic Gastritis and Gastric Carcinoma, Correlation with Prognostic Parameters

International Nuclear Information System (INIS)

Samaka, R.M.; Abdou, A.G.; Abd El-Wahed, M.M.; Kandil, M.A.; El-Kady, N.M.

2006-01-01

Background: Cyclooxygenase-2 (Cox-2) is the inducible form of cyclooxygenase enzyme. Cox-2 is induced in numerous processes such as cellular growth, differentiation, inflammation and tumorigenesis. Purpose: Assessment of Cox-2 expression in chronic gastritis s and gastric carcinoma. Material and Methods: Sixteen chronic gastritis (CG) and 43 gastric carcinoma cases were subjected to an immunohistochemical approach using anti Cox-2 antibody. Results: All CG cases displayed positive epithelial Cox-2 expression with only 25% positivity for stromal expression. Eighty six percent of gastric carcinoma showed epithelial Cox-2 expression that was significantly correlated with lymph node involvement (p=0.01), advanced stage (p=0.01), high micro vessel density (MVD) (p=0.0001), vascular invasion (p=0.002), peri neural invasion (p=0.0 I) and low apoptotic count (p<0.0001). Stromal Cox-2 expression was seen in 79% of gastric carcinoma cases and was significantly associated with low apoptotic count (p=0.0007), vascular invasion (p=0.001) and high micro vessel density (MVD) (p=0.0003). Only stromal Cox2 expression was significantly higher in gastric carcinoma than chronic gastritis (p=0.0001). Conclusions: Cox-2 appears to be involved in gastric carcinoma progression as it promotes angio genesis, suppresses apoptosis and facilitates invasion and metastasis Double expression of Cox-2 in gastric carcinoma epithelium and stroma and significant association between them demonstrate a paracrine cross effect between stromal and malignant epithelium

Baicalein inhibits pulmonary carcinogenesis-associated inflammation and interferes with COX-2, MMP-2 and MMP-9 expressions in-vivo

Energy Technology Data Exchange (ETDEWEB)

Chandrashekar, Naveenkumar; Selvamani, Asokkumar; Subramanian, Raghunandhakumar; Pandi, Anandakumar; Thiruvengadam, Devaki, E-mail: devakit@yahoo.co.uk

2012-05-15

-α, IL-1β, i-NOS and NF-κBp65 at protein levels. ► BE modulates the expressions of MMP-2, MMP-9 and COX-2 at protein and mRNA levels. ► BE decreases LPO levels and enhances antioxidant status.

Pleurotus giganteus (Berk. Karun & Hyde), the giant oyster mushroom inhibits NO production in LPS/H2O2 stimulated RAW 264.7 cells via STAT 3 and COX-2 pathways.

Science.gov (United States)

Baskaran, Asweni; Chua, Kek Heng; Sabaratnam, Vikineswary; Ravishankar Ram, Mani; Kuppusamy, Umah Rani

2017-01-13

Pleurotus giganteus (Berk. Karunarathna and K.D. Hyde), has been used as a culinary mushroom and is known to have medicinal properties but its potential as an anti-inflammatory agent to mitigate inflammation triggered diseases is untapped. In this study, the molecular mechanism underlying the protective effect of ethanol extract of P. giganteus (EPG) against lipopolysaccharide (LPS) and combination of LPS and hydrogen peroxide (H 2 O 2 )-induced inflammation on RAW 264.7 macrophages was investigated. The effect of EPG on nitric oxide (NO) production as an indicator of inflammation in RAW 264.7 macrophages was estimated based on Griess reaction that measures nitrite level. The expressions of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), NF-kB activating protein (NKAP), signal transducer and activator of transcription 3 protein (STAT 3) and glutathione peroxidase (GPx) genes were assessed using real time reverse transcription polymerase chain reaction (RT-PCR) approach. EPG (10 μg/ml) showed the highest reduction in the LPS-induced NO production in RAW 264.7 macrophages and significantly suppressed (p < 0.05) the expression iNOS, STAT 3 and COX-2. There was a significant increase (p < 0.05) in combination of LPS and H 2 O 2 - induced iNOS production when compared to the LPS-induced iNOS production in RAW 264.7 macrophages and this concurred with the NO production which was attenuated by EPG at 10 μg/ml. A significant (p < 0.05) down regulation was observed in the combination of LPS and H 2 O 2 -induced iNOS and GPx expression by EPG. Our data suggest that the anti-inflammatory activity of EPG is mediated via the suppression of the STAT 3 and COX-2 pathways and can serve as potential endogenous antioxidant stimulant.

Resistance to ursolic acid-induced apoptosis through involvement of melanogenesis and COX-2/PGE{sub 2} pathways in human M4Beu melanoma cancer cells

Energy Technology Data Exchange (ETDEWEB)

Hassan, Lama; Pinon, Aline [Laboratory of Chemistry of Natural Substances, Faculty of Pharmacy, University of Limoges, FR 3503 GEIST, EA1069, Limoges (France); Limami, Youness [Laboratoire National de Référence (LNR), Université Mohammed VI des Sciences de la Santé, Casablanca (Morocco); Seeman, Josiane; Fidanzi-Dugas, Chloe; Martin, Frederique [Laboratory of Chemistry of Natural Substances, Faculty of Pharmacy, University of Limoges, FR 3503 GEIST, EA1069, Limoges (France); Badran, Bassam [Laboratory of Cancer Biology and Molecular Immunology, Faculty of Sciences, Lebanese University, Beirut (Lebanon); Simon, Alain [Laboratory of Chemistry of Natural Substances, Faculty of Pharmacy, University of Limoges, FR 3503 GEIST, EA1069, Limoges (France); Liagre, Bertrand, E-mail: bertrand.liagre@unilim.fr [Laboratory of Chemistry of Natural Substances, Faculty of Pharmacy, University of Limoges, FR 3503 GEIST, EA1069, Limoges (France)

2016-07-01

Melanoma is one of the most aggressive forms of cancer with a continuously growing incidence worldwide and is usually resistant to chemotherapy agents, which is due in part to a strong resistance to apoptosis. Previously, we had showed that B16-F0 murine melanoma cells undergoing apoptosis are able to delay their own death induced by ursolic acid (UA), a natural pentacyclic triterpenoid compound. We had demonstrated that tyrosinase and TRP-1 up-regulation in apoptotic cells and the subsequent production of melanin were implicated in an apoptosis resistance mechanism. Several resistance mechanisms to apoptosis have been characterized in melanoma such as hyperactivation of DNA repair mechanisms, drug efflux systems, and reinforcement of survival signals (PI3K/Akt, NF-κB and Raf/MAPK pathways). Otherwise, other mechanisms of apoptosis resistance involving different proteins, such as cyclooxygenase-2 (COX-2), have been described in many cancer types. By using a strategy of specific inhibition of each ways, we suggested that there was an interaction between melanogenesis and COX-2/PGE{sub 2} pathway. This was characterized by analyzing the COX-2 expression and activity, the expression of tyrosinase and melanin production. Furthermore, we showed that anti-proliferative and proapoptotic effects of UA were mediated through modulation of multiple signaling pathways including Akt and ERK-1/2 proteins. Our study not only uncovers underlying molecular mechanisms of UA action in human melanoma cancer cells but also suggest its great potential as an adjuvant in treatment and cancer prevention.

Regulation of Expression of Renal Organic Anion Transporters OAT1 and OAT3 in a Model of Ischemia/Reperfusion Injury

Directory of Open Access Journals (Sweden)

Christina Preising

2015-08-01

Full Text Available Background: Recently, we gained evidence that impairment of rOat1 and rOat3 expression induced by ischemic acute kidney injury (AKI is mediated by COX metabolites and this suppression might be critically involved in renal damage. Methods: (i Basolateral organic anion uptake into proximal tubular cells after model ischemia and reperfusion (I/R was investigated by fluorescein uptake. The putative promoter sequences from hOAT1 (SLC22A6 and hOAT3 (SCL22A8 were cloned into a reporter plasmid, transfected into HEK cells and (ii transcriptional activity was determined after model ischemia and reperfusion as a SEAP reporter gen assay. Inhibitors or antagonists were applied with the beginning of reperfusion. Results: By using inhibitors of PKA (H89 and PLC (U73122, antagonists of E prostanoid receptor type 2 (AH6809 and type 4 (L161,982, we gained evidence that I/R induced down regulation of organic anion transport is mediated by COX1 metabolites via E prostanoid receptor type 4. The latter signaling was confirmed by application of butaprost (EP2 agonist or TCS2510 (EP4 agonist to control cells. In brief, the latter signaling was verified for the transcriptional activity in the reporter gen assay established. Therein, selective inhibitors for COX1 (SC58125 and COX2 (SC560 were also applied. Conclusion: Our data show (a that COX1 metabolites are involved in the regulation of renal organic anion transport(ers after I/R via the EP4 receptor and (b that this is due to transcriptional regulation of the respective transporters. As the promoter sequences cloned were of human origin and expressed in a human renal epithelial cell line we (c hypothesize that the regulatory mechanisms described after I/R is meaningful for humans as well.

Predictive utility of cyclo-oxygenase-2 expression by colon and rectal cancer.

Science.gov (United States)

Lobo Prabhu, Kristel C; Vu, Lan; Chan, Simon K; Phang, Terry; Gown, Allen; Jones, Steven J; Wiseman, Sam M

2014-05-01

Cyclo-oxygenase-2 (COX-2), an inducible enzyme expressed in areas of inflammation, is a target of interest for colorectal cancer therapy. Currently, the predictive significance of COX-2 in colorectal cancer remains unclear. Tissue microarrays were constructed using 118 colon cancer and 85 rectal cancer specimens; 44 synchronous metastatic colon cancer and 22 rectal cancer lymph nodes were also evaluated. COX-2 expression was assessed by immunohistochemistry. Univariate analysis was used to determine the predictive significance of clinicopathologic variables. Overall survival, disease-specific survival, and disease-free survival were the main outcomes examined. COX-2 was found to be expressed in 93% of colon cancers and 87% of rectal cancers. Decreased COX-2 expression was related to decreased disease-specific survival (P = .016) and decreased disease-free survival (P = .019) in the rectal cancer cohort but not in the colon cancer cohort. COX-2 expression has predictive utility for management of rectal but not colon cancer. Copyright © 2014 Elsevier Inc. All rights reserved.

Expression of p63 and Cyclooxygenase-2 and Their Correlation in Skin Tumors

Institute of Scientific and Technical Information of China (English)

WU Yan; LIU Houjun; LI Jiawen

2007-01-01

To study the expression of p63 and cyclooxygenase-2 (cox-2) in skin tumors and evaluate the correlation between p63 and cox-2, the expressions of cox-2 and p63 were measured by streptavidin-peroxidase complex immunohistochemical technique in 17 cases of skin squamous cell carcinoma (SCC), 19 cases of Bowen's disease(Bowen), 11 cases of actinic keratosis(AK), 12 cases of seborreic keratosis(SK) and 13 specimens of normal skin. Our results showed that the expression of p63 in skin squamous cell carcinoma, Bowen's disease and actinic keratosis were significantly higher than that in seborreic keratosis, while the expression of p63 in seborreic keratosis was significantly higher than that in normal skin. The expression of cox-2 in skin squamous cell carcinoma,Bowen's disease and actinic keratosis were significantly higher than that in seborreic keratosis, while no statistical difference was noted in the expression of cox-2 between seborreic keratosis and normal skin. Cox-2 expression was positively correlated with the high p63 expression in malignant skin tumors. The increased expression of cox-2 and p63 may play an important role in the development of skin tumors and work synergetically in malignant skin tumors.

TGF-β1 downregulates COX-2 expression leading to decrease of PGE2 production in human lung cancer A549 cells, which is involved in fibrotic response to TGF-β1.

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Erina Takai

Full Text Available Transforming growth factor-ß1 (TGF-β1 is a multifunctional cytokine that is involved in various pathophysiological processes, including cancer progression and fibrotic disorders. Here, we show that treatment with TGF-β1 (5 ng/mL induced downregulation of cyclooxygenase-2 (COX-2, leading to reduced synthesis of prostaglandin E2 (PGE2, in human lung cancer A549 cells. Treatment of cells with specific inhibitors of COX-2 or PGE2 receptor resulted in growth inhibition, indicating that the COX-2/PGE2 pathway contributes to proliferation in an autocrine manner. TGF-β1 treatment induced growth inhibition, which was attenuated by exogenous PGE2. TGF-β1 is also a potent inducer of epithelial mesenchymal transition (EMT, a phenotype change in which epithelial cells differentiate into fibroblastoid cells. Supplementation with PGE2 or PGE2 receptor EP4 agonist PGE1-alcohol, as compared with EP1/3 agonist sulprostone, inhibited TGF-β1-induced expression of fibronectin and collagen I (extracellular matrix components. Exogenous PGE2 or PGE2 receptor agonists also suppressed actin remodeling induced by TGF-β1. These results suggest that PGE2 has an anti-fibrotic effect. We conclude that TGF-β1-induced downregulation of COX-2/PGE2 signaling is involved in facilitation of fibrotic EMT response in A549 cells.

The association of four common polymorphisms from four candidate genes (COX-1, COX-2, ITGA2B, ITGA2 with aspirin insensitivity: a meta-analysis.

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Zhiyuan Weng

Full Text Available OBJECTIVE: Evidence is mounting suggesting that a strong genetic component underlies aspirin insensitivity. To generate more information, we aimed to evaluate the association of four common polymorphisms (rs3842787, rs20417, rs201184269, rs1126643 from four candidate genes (COX-1, COX-2, ITGA2B, ITGA2 with aspirin insensitivity via a meta-analysis. METHODS AND RESULTS: In total, there were 4 (353/595, 6 (344/698, 10 (588/878 and 7 (209/676 articles (patients/controls qualified for rs3842787, rs20417, rs20118426 and rs1126643, respectively. The data were extracted in duplicate and analyzed by STATA software (Version 11.2. The risk estimate was expressed as odds ratio (OR and 95% confidence interval (95% CI. Analyses of the full data set indicated significant associations of rs20417 (OR; 95% CI; P: 1.86; 1.44-2.41; <0.0005 and rs1126643 (2.37; 1.44-3.89; 0.001 with aspirin insensitivity under allelic model. In subgroup analyses, the risk estimate for rs1126643 was greatly potentiated among patients with aspirin semi-resistance relative to those with aspirin resistance, especially under dominant model (aspirin semi-resistance: 5.44; 1.42-20.83; 0.013 versus aspirin resistance: 1.96; 1.07-3.6; 0.03. Further grouping articles by ethnicity observed a stronger prediction of all, but rs20417, examined polymorphisms for aspirin insensitivity in Chinese than in Caucasians. Finally, meta-regression analyses observed that the differences in percentage of coronary artery disease (P = 0.034 and averaged platelet numbers (P = 0.012 between two groups explained a large part of heterogeneity for rs20417 and rs1126643, respectively. CONCLUSION: Our findings provide strong evidence that COX-2 and ITGA2 genetic defects might increase the risk of having aspirin insensitivity, especially for aspirin semi-resistance and in Chinese populations.

GluN2B/CaMKII mediates CFA-induced hyperalgesia via HDAC4-modified spinal COX2 transcription.

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Lai, Cheng-Yuan; Hsieh, Ming-Chun; Ho, Yu-Cheng; Chen, Gin-Den; Chou, Dylan; Ruan, Ting; Lee, An-Sheng; Wang, Hsueh-Hsiao; Chau, Yat-Pang; Peng, Hsien-Yu; Lai, Cheng-Hung

2018-06-01

Histone deacetylase 4 (HDAC4), which actively shuttles between the nucleus and cytoplasm, is an attractive candidate for a repressor mechanism in epigenetic modification. However, the potential role of HDAC4-dependent epigenetics in the neural plasticity underlying the development of inflammatory pain has not been well established. By injecting complete Freund's adjuvant (CFA) into the hind-paw of Sprague-Dawley rats (200-250 g), we found animals displayed behavioral hyperalgesia was accompanied with HDAC4 phosphorylation and cytoplasmic redistribution in the dorsal horn neurons. Cytoplasmic HDAC4 retention led to its uncoupling with the COX2 promoter, hence prompting spinal COX2 transcription and expression in the dorsal horn. Moreover, the GluN2B-bearing N-methyl-d-aspartate receptor (GluN2B-NMDAR)/calmodulin-dependent protein kinase II (CaMKII) acted as an upstream cascade to facilitate HDAC4 phosphorylation/redistribution-associated spinal COX2 expression after inflammatory insults. The results of this pilot study demonstrated that the development and/or maintenance of inflammatory pain involved the spinal HDAC4-dependent epigenetic mechanisms. Our findings open up a new avenue for the development of a novel medical strategy for the relief of inflammatory pain. Copyright © 2018 Elsevier Ltd. All rights reserved.

Screening of Missense SNPs in Coding Regions of COX-2 as a Key Enzyme Involved in Cancer

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Sodabeh Jahanbakhsh-Godehkahriz

2013-09-01

Full Text Available Background & Objectives: Non-synonymous single nucleotide polymorphism (nsSNPs which results in disruption of protein function are used as markers in linkage and association of human proteins that might be involved in diseases and cancers .   Methods: To study the functional effect of nsSNP in cyclooxygenase-2 (COX2 amino acids, the nucleotide sequences encoding COX-2 gene in cancers were extracted from the NCBI (gi|223941909 data bank (283 cases and analyzed by SIFT, I-Mutant 2.0, SNP and GO, PANTHER and FASTSNP servers. These servers involve programs that predict the effects of amino acid substitution on protein function, stability and missense .   Results: COX-2 is an essential enzyme for the production of pro-inflammatory prostaglandins which are relevant to cancer development and progression. The substitutions in some positions such as R228H and S428A of COX-2 in most of cancers linked to reformed protein function through disruption in enzyme active site.   Conclusion: Amino acid substitutions as a consequence of COX-2 nsSNPs have important role in human disease. Substitutions which are located in catalytic domain are important for the enzymatic function of COX-2 and associated with higher expression of COX-2.

Histamine, carbachol, and serotonin induce hyperresponsiveness to ATP in guinea pig tracheas: involvement of COX-2 pathway.

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Montaño, Luis M; Carbajal, Verónica; Vargas, Mario H; García-Hernández, Luz M; Díaz-Hernández, Verónica; Checa, Marco; Barajas-López, Carlos

2013-08-01

Extracellular ATP promotes an indirect contraction of airway smooth muscle via the secondary release of thromboxane A2 (TXA2) from airway epithelium. Our aim was to evaluate if common contractile agonists modify this response to ATP. Tracheas from sensitized guinea pigs were used to evaluate ATP-induced contractions before and after a transient contraction produced by histamine, carbachol, or serotonin. Epithelial mRNA for COX-1 and COX-2 was measured by RT-PCR and their expression assessed by immunohistochemistry. Compared with the initial response, ATP-induced contraction was potentiated by pretreatment with histamine, carbachol, or serotonin. Either suramin (antagonist of P2X and P2Y receptors) plus RB2 (antagonist of P2Y receptors) or indomethacin (inhibitor of COX-1 and COX-2) annulled the ATP-induced contraction, suggesting that it was mediated by P2Y receptor stimulation and TXA2 production. When COX-2 was inhibited by SC-58125 or thromboxane receptors were antagonized by SQ-29548, just the potentiation was abolished, leaving the basal response intact. Airway epithelial cells showed increased COX-2 mRNA after stimulation with histamine or carbachol, but not serotonin, while COX-1 mRNA was unaffected. Immunochemistry corroborated this upregulation of COX-2. In conclusion, we showed for the first time that histamine and carbachol cause hyperresponsiveness to ATP by upregulating COX-2 in airway epithelium, which likely increases TXA2 production. Serotonin-mediated hyperresponsiveness seems to be independent of COX-2 upregulation, but nonetheless is TXA2 dependent. Because acetylcholine, histamine, and serotonin can be present during asthmatic exacerbations, their potential interactions with ATP might be relevant in its pathophysiology.

IL1β-mediated Stromal COX-2 signaling mediates proliferation and invasiveness of colonic epithelial cancer cells

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Zhu, Yingting; Zhu, Min; Lance, Peter

2012-01-01

COX-2 is a major inflammatory mediator implicated in colorectal inflammation and cancer. However, the exact origin and role of COX-2 on colorectal inflammation and carcinogenesis are still not well defined. Recently, we reported that COX-2 and iNOS signalings interact in colonic CCD18Co fibroblasts. In this article, we investigated whether activation of COX-2 signaling by IL1β in primary colonic fibroblasts obtained from normal and cancer patients play a critical role in regulation of proliferation and invasiveness of human colonic epithelial cancer cells. Our results demonstrated that COX-2 level was significantly higher in cancer associated fibroblasts than that in normal fibroblasts with or without stimulation of IL-1β, a powerful stimulator of COX-2. Using in vitro assays for estimating proliferative and invasive potential, we discovered that the proliferation and invasiveness of the epithelial cancer cells were much greater when the cells were co-cultured with cancer associated fibroblasts than with normal fibroblasts, with or without stimulation of IL1β. Further analysis indicated that the major COX-2 product, prostaglandin E 2 , directly enhanced proliferation and invasiveness of the epithelial cancer cells in the absence of fibroblasts. Moreover, a selective COX-2 inhibitor, NS-398, blocked the proliferative and invasive effect of both normal and cancer associate fibroblasts on the epithelial cancer cells, with or without stimulation of IL-1β. Those results indicate that activation of COX-2 signaling in the fibroblasts plays a major role in promoting proliferation and invasiveness of the epithelial cancer cells. In this process, PKC is involved in the activation of COX-2 signaling induced by IL-1β in the fibroblasts.

Ihh/Gli2 signaling promotes osteoblast differentiation by regulating Runx2 expression and function.

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Shimoyama, Atsuko; Wada, Masahiro; Ikeda, Fumiyo; Hata, Kenji; Matsubara, Takuma; Nifuji, Akira; Noda, Masaki; Amano, Katsuhiko; Yamaguchi, Akira; Nishimura, Riko; Yoneda, Toshiyuki

2007-07-01

Genetic and cell biological studies have indicated that Indian hedgehog (Ihh) plays an important role in bone development and osteoblast differentiation. However, the molecular mechanism by which Ihh regulates osteoblast differentiation is complex and remains to be fully elucidated. In this study, we investigated the role of Ihh signaling in osteoblast differentiation using mesenchymal cells and primary osteoblasts. We observed that Ihh stimulated alkaline phosphatase (ALP) activity, osteocalcin expression, and calcification. Overexpression of Gli2- but not Gli3-induced ALP, osteocalcin expression, and calcification of these cells. In contrast, dominant-negative Gli2 markedly inhibited Ihh-dependent osteoblast differentiation. Ihh treatment or Gli2 overexpression also up-regulated the expression of Runx2, an essential transcription factor for osteoblastogenesis, and enhanced the transcriptional activity and osteogenic action of Runx2. Coimmunoprecipitation analysis demonstrated a physical interaction between Gli2 and Runx2. Moreover, Ihh or Gli2 overexpression failed to increase ALP activity in Runx2-deficient mesenchymal cells. Collectively, these results suggest that Ihh regulates osteoblast differentiation of mesenchymal cells through up-regulation of the expression and function of Runx2 by Gli2.

Role of IL-1 beta and COX2 in silica-induced IL-6 release and loss of pneumocytes in co-cultures.

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Herseth, Jan I; Refsnes, Magne; Låg, Marit; Schwarze, Per E

2009-10-01

The pro-inflammatory cytokines IL-1 beta, TNF-alpha and IL-6 are of great importance in the development of silica-induced lung damage and repair. In this study we investigated the role of IL-1 beta, TNF-alpha and COX2 in silica-induced regulation of IL-6 release and pneumocyte loss in various mono- and co-cultures of monocytes, pneumocytes and endothelial cells. All co-cultures with monocytes, and especially cultures including endothelial cells, showed an increase of silica-induced release of IL-6 compared to the respective monocultures. Treatment with the antagonist IL-1 ra strongly decreased IL-1 beta and IL-6 release in contact co-cultures of monocytes and pneumocytes. COX2 up-regulation by silica and IL-1 beta was eliminated by IL-1 ra. Inhibition of COX2 markedly reduced both IL-1 beta and IL-6 release. IL-1 ra was more effective than COX2-inhibition in reduction of IL-6, but not of IL-1 beta. Silica-induced pneumocyte loss was reduced by IL-1 beta, but this effect was not counteracted by the IL-1 receptor antagonist. Our findings suggest that silica-induced IL-6 release from pneumocytes is mainly mediated via IL-1 beta release from the monocytes, via both COX2-dependent and -independent pathways. Notably, COX2-derived mediators seem crucial for a positive feed-back regulation of IL-1 beta release from the monocytes. In contrast to silica-induced IL-6, the reduction in pneumocyte loss by IL-1 beta does not seem to be regulated through an IL-1R1-dependent mechanism.

Resveratrol Targeting of Carcinogen-Induced Brain Endothelial Cell Inflammation Biomarkers MMP-9 and COX-2 is Sirt1-Independent

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Borhane Annabi

2012-01-01

Full Text Available The occurrence of a functional relationship between the release of metalloproteinases (MMPs and the expression of cyclooxygenase (COX-2, two inducible pro-inflammatory biomarkers with important pro-angiogenic effects, has recently been inferred. While brain endothelial cells play an essential role as structural and functional components of the blood-brain barrier (BBB, increased BBB breakdown is thought to be linked to neuroinflammation. Chemopreventive mechanisms targeting both MMPs and COX-2 however remain poorly investigated. In this study, we evaluated the pharmacological targeting of Sirt1 by the diet-derived and antiinflammatory polyphenol resveratrol. Total RNA, cell lysates, and conditioned culture media from human brain microvascular endothelial cells (HBMEC were analyzed using qRT-PCR, immunoblotting, and zymography respectively. Tissue scan microarray analysis of grade I–IV brain tumours cDNA revealed increased gene expression of Sirt-1 from grade I–III but surprisingly not in grade IV brain tumours. HBMEC were treated with a combination of resveratrol and phorbol 12-myristate 13-acetate (PMA, a carcinogen known to increase MMP-9 and COX-2 through NF-κB. We found that resveratrol efficiently reversed the PMA-induced MMP-9 secretion and COX-2 expression. Gene silencing of Sirt1, a critical modulator of angiogenesis and putative target of resveratrol, did not lead to significant reversal of MMP-9 and COX-2 inhibition. Decreased resveratrol inhibitory potential of carcinogen-induced IκB phosphorylation in siSirt1-transfected HBMEC was however observed. Our results suggest that resveratrol may prevent BBB disruption during neuroinflammation by inhibiting MMP-9 and COX-2 and act as a pharmacological NF-κB signal transduction inhibitor independent of Sirt1.

Aryl hydrocarbon receptor-dependent retention of nuclear HuR suppresses cigarette smoke-induced cyclooxygenase-2 expression independent of DNA-binding.

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Zago, Michela; Sheridan, Jared A; Nair, Parameswaran; Rico de Souza, Angela; Gallouzi, Imed-Eddine; Rousseau, Simon; Di Marco, Sergio; Hamid, Qutayba; Eidelman, David H; Baglole, Carolyn J

2013-01-01

The aryl hydrocarbon receptor (AhR), a ligand-activated transcription factor that responds to man-made environmental toxicants, has emerged as an endogenous regulator of cyclooxygenase-2 (Cox-2) by a mechanism that is poorly understood. In this study, we first used AhR-deficient (AhR(-/-) ) primary pulmonary cells, together with pharmacological tools to inhibit new RNA synthesis, to show that the AhR is a prominent factor in the destabilization of Cox-2 mRNA. The destabilization of Cox-2 mRNA and subsequent suppression of cigarette smoke-induced COX-2 protein expression by the AhR was independent of its ability to bind the dioxin response element (DRE), thereby differentiating the DRE-driven toxicological AhR pathway from its anti-inflammatory abilities. We further describe that the AhR destabilizes Cox-2 mRNA by sequestering HuR within the nucleus. The role of HuR in AhR stabilization of Cox-2 mRNA was confirmed by knockdown of HuR, which resulted in rapid Cox-2 mRNA degradation. Finally, in the lungs of AhR(-/-) mice exposed to cigarette smoke, there was little Cox-2 mRNA despite robust COX-2 protein expression, a finding that correlates with almost exclusive cytoplasmic HuR within the lungs of AhR(-/-) mice. Therefore, we propose that the AhR plays an important role in suppressing the expression of inflammatory proteins, a function that extends beyond the ability of the AhR to respond to man-made toxicants. These findings open the possibility that a DRE-independent AhR pathway may be exploited therapeutically as an anti-inflammatory target.

GROWTH FACTORS AND COX2 IN WOUND HEALING: AN EXPERIMENTAL STUDY WITH EHRLICH TUMORS.

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Salgado, Flávio L L; Artigiani-Neto, Ricardo; Lopes-Filho, Gaspar de Jesus

2016-01-01

Healing is an innate biological phenomenon, and carcinogenesis acquired, but with common humoral and cellular elements. Carcinogenesis interferes negatively in healing. To evaluate the histological changes in laparotomy scars of healthy Balb/c mice and with an Ehrlich tumor in its various forms of presentation. Fifty-four mice were divided into three groups of 18 animals. First group was the control; the second had Ehrlich tumor with ascites; and the third had the subcutaneous form of this tumor. Seven days after tumor inoculation, all 54 mice were submitted to laparotomy. All of the animals in the experiment were operated on again on 7th day after surgery, with resection of the scar and subsequent euthanasia of the animal. The scars were sent for histological assessment using immunohistochemical techniques to evaluate Cox-2 (cyclooxygenase 2), VEGF (vascular endothelial growth factor) and FGF (fibroblast growth factor). Semi-quantitatively analysis was done in the laparotomy scars and in the abdominal walls far away from the site of the operation. Assessing the weight of the animals, the correct inoculation of the tumor and weight gain in the group with tumoral ascites was observed. The histological studies showed that groups with the tumor showed a statistically significant higher presence of Cox-2 compared to the control. In the Cox-2 analysis of the abdominal wall, the ascites group showed the most significant difference. VEGF did not present any significant differences between the three groups, regardless of the site. The FGF showed a significant increase in animals with the tumor. Histological findings in both laparotomy scar and the abdominal wall showed that with Ehrlich's neoplasia there was an exacerbated inflammatory response, translated by more intense expression of Cox-2 and greater fibroblast proliferation, translated by more intense expression of FGF, that is, it stimulated both the immediate inflammatory reactions, observed with Cox-2 reactions, and

Cyclooxygenase-2 (COX-2) Polymorphisms and Risk of Inflammatory Bowel Disease in a Scottish and Danish Case–Control Study

DEFF Research Database (Denmark)

Andersen, Vibeke; Nimmo, Elaine; Krarup, Henrik B.

2011-01-01

Background: Inflammatory bowel diseases (IBDs) are a result of interactions between luminal pathogens and the intestinal immune response. Cyclooxygenase-2 (COX-2) plays a key role in the regulation of the inflammatory response upon stimulation by luminal pathogens via Toll-like receptors. Methods...

Prevention of upper aerodigestive tract cancer in zinc-deficient rodents: Inefficacy of genetic or pharmacological disruption of COX-2

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Fong, Louise Y.Y.; Jiang, Yubao; Riley, Maurisa; Liu, Xianglan; Smalley, Karl J.; Guttridge, Denis C.; Farber, John L.

2009-01-01

Zinc deficiency in humans is associated with an increased risk of upper aerodigestive tract (UADT) cancer. In rodents, zinc deficiency predisposes to carcinogenesis by causing proliferation and alterations in gene expression. We examined whether in zinc-deficient rodents, targeted disruption of the cyclooxygenase (COX)-2 pathway by the COX-2 selective inhibitor celecoxib or by genetic deletion prevent UADT carcinogenesis. Tongue cancer prevention studies were conducted in zinc-deficient rats previously exposed to a tongue carcinogen by celecoxib treatment with or without zinc replenishment, or by zinc replenishment alone. The ability of genetic COX-2 deletion to protect against chemically-induced for-estomach tumorigenesis was examined in mice on zinc-deficient versus zinc-sufficient diet. The expression of 3 predictive bio-markers COX-2, nuclear factor (NF)-κ B p65 and leukotriene A4 hydrolase (LTA4H) was examined by immunohistochemistry. In zinc-deficient rats, celecoxib without zinc replenishment reduced lingual tumor multiplicity but not progression to malignancy. Celecoxib with zinc replenishment or zinc replenishment alone significantly lowered lingual squamous cell carcinoma incidence, as well as tumor multiplicity. Celecoxib alone reduced overexpression of the 3 biomarkers in tumors slightly, compared with intervention with zinc replenishment. Instead of being protected, zinc-deficient COX-2 null mice developed significantly greater tumor multiplicity and forestomach carcinoma incidence than wild-type controls. Additionally, zinc-deficient COX-2−/− forestomachs displayed strong LTA4H immunostaining, indicating activation of an alter-native pathway under zinc deficiency when the COX-2 pathway is blocked. Thus, targeting only the COX-2 pathway in zinc-deficient animals did not prevent UADT carcinogenesis. Our data suggest zinc supplementation should be more thoroughly explored in human prevention clinical trials for UADT cancer. PMID:17985342

COX-2 is associated with periodontitis in Europeans

NARCIS (Netherlands)

Schaefer, A.S.; Richter, G.M.; Nothnagel, M.; Laine, M.L.; Noack, B.; Glas, J.; Schrezenmeir, J.; Groessner-Schreiber, B.; Jepsen, S.; Loos, B.G.; Schreiber, S.

2010-01-01

COX-2 plays an important role in periodontitis by mediating inflammatory reactions in periodontal tissues, and the COX-2 polymorphisms rs20417 and rs689466 have been reported to be associated with periodontitis in populations of Taiwanese and Chinese ethnicity. To test whether these variants were

Regulation of hepatic PPARγ2 and lipogenic gene expression by melanocortin

International Nuclear Information System (INIS)

Poritsanos, Nicole J.; Wong, Davie; Vrontakis, Maria E.; Mizuno, Tooru M.

2008-01-01

The central melanocortin system regulates hepatic lipid metabolism. Hepatic lipogenic gene expression is regulated by transcription factors including sterol regulatory element-binding protein 1c (SREBP-1c), carbohydrate responsive element-binding protein (ChREBP), and peroxisome proliferator-activated receptor γ2 (PPARγ2). However, it is unclear if central melanocortin signaling regulates hepatic lipogenic gene expression through the activation of these transcription factors. To delineate the molecular mechanisms by which the melanocortin system regulates hepatic lipid metabolism, we examined the effect of intracerebroventricular injection of SHU9119, a melanocortin receptor antagonist, on hepatic expression levels of genes involved in lipid metabolism in mice. SHU9119 treatment increased hepatic triglyceride content and mRNA levels of lipogenic genes, SREBP-1c, and PPARγ2, whereas it did not cause any changes in hepatic ChREBP mRNA levels. These findings suggest that reduced central melanocortin signaling increases hepatic lipid deposition by stimulating hepatic lipogenic gene expression at least partly through the activation of SREBP-1c and PPARγ2

In vitro and In Silico Studies on Curcumin and Its Analogues as Dual Inhibitors for cyclooxygenase-1 (COX-1 and cyclooxygenase-2 (COX-2

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Nunung Yuniarti

2012-03-01

Full Text Available Curcumin has been widely reported as an anti-inflammatory agent isolated from the plant Curcuma longa L. (turmeric. This anti-inflammatory activity was associated with the ability of this compound to inhibit the activity of both cyclooxygenase-1 (COX-1 and cyclooxygenase-2 (COX-2 in arachidonic acid metabolism. Dual COX-1 and COX-2 inhibitors are preferred to be employed in the therapy of chronic inflammatory diseases compared to selective inhibitors, since it was reported that the use of selective inhibitors led to severe adverse side effect. In the present study, in vitro and in silico assays on curcumin and its analogues as dual inhibitors for both COX-1 and COX-2 were performed. The results provide theoretical contribution in understanding the ligand-protein interactions at the molecular level to develop new curcumin analogues which possess better anti-inflammatory activity as well as to avoid unsolicited side effects.

Comparative study of cyclioxygenase-2 expression and HER-2/neu amplification in Korean and caucasian woman with early-onset breast carcinoma

International Nuclear Information System (INIS)

Choi, Doo Ho; Kim, Eun Seog; Kim, Yong Ho; Jin, So Young; Lee, Dong Wha; Haffty, Bruce G.

2004-01-01

The purpose of this work was to study the differences of cyclooxygenase (COX-2) expression between Korean and Caucasian patients with early-onset breast carcinoma by immunohistochemistry. The test were analyzed to find a correlation between COX-2 and other biomarkers including HER-2/neu amplification, because we previously reported that a significant difference had been found in the expression of HER-2/neu between the two races. Furthermore, we investigated prognostic significance of COX-2 in Korean patients. Sixty Korean women who were diagnosed breast carcinoma at 45 years old or younger and 60 Caucasian women with breast carcinoma were selected for this study. The median age of both groups was 37 years and tumor sizes were distributed evenly between the two group. Paraffin embedded blocks of primary tumor were processed for immunohistochemical staining of COX-2. The COX-2 expression was evaluated according to the percentage of positive cells and the intensity of staining. And the results were compared with the data of the previous studies to find correlation between COX-2 and other parameters and survival data. Proportion of the COX-2 expression in total patients was 27.6%. The percentage of tumors that stained positive for COX-2 in Korean and Caucasian women with early-onset breast carcinoma were 37.9% and 20.8%, respectively. The difference was statistically not significant (ρ 0.090). Expression of COX-2 was not associated with several clinicopathologic parameters including HER-2/neu overexpression, but negative estrogen receptor status was correlated with significance (ρ = 0.046). The 5 year disease free survival rate for patients with COX-2 expression was 67.9%, compared to 81.9% of the COX-2 negative patients and the result was statistically not significant. A significant difference was not found in the expression of COX-2 between the two groups of patients with early-onset breast carcinoma. And correlation between COX-2 and other parameters was not

N-MYC down-regulated-like proteins regulate meristem initiation by modulating auxin transport and MAX2 expression.

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Mudgil, Yashwanti; Ghawana, Sanjay; Jones, Alan M

2013-01-01

N-MYC down-regulated-like (NDL) proteins interact with the Gβ subunit (AGB1) of the heterotrimeric G protein complex and play an important role in AGB1-dependent regulation of lateral root formation by affecting root auxin transport, auxin gradients and the steady-state levels of mRNA encoding the PIN-FORMED 2 and AUXIN 1 auxin transport facilitators. Auxin transport in aerial tissue follows different paths and utilizes different transporters than in roots; therefore, in the present study, we analyzed whether NDL proteins play an important role in AGB1-dependent, auxin-mediated meristem development. Expression levels of NDL gene family members need to be tightly regulated, and altered expression (both over-expression and down-regulation) confers ectopic growth. Over-expression of NDL1 disrupts vegetative and reproductive organ development. Reduced expression of the NDL gene family members results in asymmetric leaf emergence, twinning of rosette leaves, defects in leaf formation, and abnormal silique distribution. Reduced expression of the NDL genes in the agb1-2 (null allele) mutant rescues some of the abnormal phenotypes, such as silique morphology, silique distribution, and peduncle angle, suggesting that proper levels of NDL proteins are maintained by AGB1. We found that all of these abnormal aerial phenotypes due to altered NDL expression were associated with increases in basipetal auxin transport, altered auxin maxima and altered MAX2 expression within the inflorescence stem. NDL proteins, together with AGB1, act as positive regulators of meristem initiation and branching. AGB1 and NDL1 positively regulate basipetal inflorescence auxin transport and modulate MAX2 expression in shoots, which in turn regulates organ and lateral meristem formation by the establishment and maintenance of auxin gradients.

N-MYC down-regulated-like proteins regulate meristem initiation by modulating auxin transport and MAX2 expression.

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Yashwanti Mudgil

Full Text Available N-MYC down-regulated-like (NDL proteins interact with the Gβ subunit (AGB1 of the heterotrimeric G protein complex and play an important role in AGB1-dependent regulation of lateral root formation by affecting root auxin transport, auxin gradients and the steady-state levels of mRNA encoding the PIN-FORMED 2 and AUXIN 1 auxin transport facilitators. Auxin transport in aerial tissue follows different paths and utilizes different transporters than in roots; therefore, in the present study, we analyzed whether NDL proteins play an important role in AGB1-dependent, auxin-mediated meristem development.Expression levels of NDL gene family members need to be tightly regulated, and altered expression (both over-expression and down-regulation confers ectopic growth. Over-expression of NDL1 disrupts vegetative and reproductive organ development. Reduced expression of the NDL gene family members results in asymmetric leaf emergence, twinning of rosette leaves, defects in leaf formation, and abnormal silique distribution. Reduced expression of the NDL genes in the agb1-2 (null allele mutant rescues some of the abnormal phenotypes, such as silique morphology, silique distribution, and peduncle angle, suggesting that proper levels of NDL proteins are maintained by AGB1. We found that all of these abnormal aerial phenotypes due to altered NDL expression were associated with increases in basipetal auxin transport, altered auxin maxima and altered MAX2 expression within the inflorescence stem.NDL proteins, together with AGB1, act as positive regulators of meristem initiation and branching. AGB1 and NDL1 positively regulate basipetal inflorescence auxin transport and modulate MAX2 expression in shoots, which in turn regulates organ and lateral meristem formation by the establishment and maintenance of auxin gradients.

Celecoxib suppresses fibroblast growth factor-2 expression in pancreatic ductal adenocarcinoma PANC-1 cells.

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Li, Jing; Luo, Miaosha; Wang, Yan; Shang, Boxin; Dong, Lei

2016-09-01

The inhibition of cyclooxygenase (COX)-2 has been reported to suppress growth and induce apoptosis in human pancreatic cancer cells. Nevertheless, the precise biological mechanism of how celecoxib, a selective COX-2 inhibitor, regulates the growth and invasion of pancreatic tumors is not completely understood. It has been shown that fibroblast growth factor-2 (FGF-2) and its receptor levels correlate with the inhibition of cancer cell proliferation, migration and invasion in pancreatic ductal adenocarcinoma (PDAC). Therefore, the aim of the present study was to examine the hypothesis that the antitumor activity of celecoxib in PDAC may be exerted through modulation of FGF-2 function. In the present study, we evaluated the effects of celecoxib on the proliferation, migration, invasion and apoptosis of the PANC-1 cell line. Western blotting and quantitative real-time polymerase chain reaction (qRT-PCR) were used to examine the expression of FGF-2, FGFR-2, ERK1/2 and MMPs. In the present study, FGF-2 and FGFR-2 were expressed in PANC-1 cells and FGF-2 exerted a stimulatory effect on phosphorylated extracellular signal regulated kinase (p-ERK) expression. Celecoxib treatment suppressed FGF-2 and FGFR-2 expression and decreased MMP-2, MMP-9 and p-ERK expression in the PANC-1 cells. Furthermore, celecoxib treatment caused the resistance of PANC-1 cells to FGF-2 induced proliferation, migration and invasion ability, as well as the increase in their apoptotic rate. Our data provide evidence that targeting FGF-2 with celecoxib may be used as an effective treatment in PDAC.

Cyclopamine and jervine induce COX-2 overexpression in human erythroleukemia cells but only cyclopamine has a pro-apoptotic effect

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Ghezali, Lamia; Leger, David Yannick; Limami, Youness; Cook-Moreau, Jeanne; Beneytout, Jean-Louis; Liagre, Bertrand

2013-01-01

Erythroleukemia is generally associated with a very poor response and survival to current available therapeutic agents. Cyclooxygenase-2 (COX-2) has been described to play a crucial role in the proliferation and differentiation of leukemia cells, this enzyme seems to play an important role in chemoresistance in different cancer types. Previously, we demonstrated that diosgenin, a plant steroid, induced apoptosis in HEL cells with concomitant COX-2 overexpression. In this study, we investigated the antiproliferative and apoptotic effects of cyclopamine and jervine, two steroidal alkaloids with similar structures, on HEL and TF1a human erythroleukemia cell lines and, for the first time, their effect on COX-2 expression. Cyclopamine, but not jervine, inhibited cell proliferation and induced apoptosis in these cells. Both compounds induced COX-2 overexpression which was responsible for apoptosis resistance. In jervine-treated cells, COX-2 overexpression was NF-κB dependent. Inhibition of NF-κB reduced COX-2 overexpression and induced apoptosis. In addition, cyclopamine induced apoptosis and COX-2 overexpression via PKC activation. Inhibition of the PKC pathway reduced both apoptosis and COX-2 overexpression in both cell lines. Furthermore, we demonstrated that the p38/COX-2 pathway was involved in resistance to cyclopamine-induced apoptosis since p38 inhibition reduced COX-2 overexpression and increased apoptosis in both cell lines. - Highlights: ► Cyclopamine alone but not jervine induces apoptosis in human erythroleukemia cells. ► Cyclopamine and jervine induce COX-2 overexpression. ► COX-2 overexpression is implicated in resistance to cyclopamine-induced apoptosis. ► Apoptotic potential of jervine is restrained by NF-κB pathway activation. ► PKC is involved in cyclopamine-induced apoptosis and COX-2 overexpression

Cyclopamine and jervine induce COX-2 overexpression in human erythroleukemia cells but only cyclopamine has a pro-apoptotic effect

Energy Technology Data Exchange (ETDEWEB)

Ghezali, Lamia; Leger, David Yannick; Limami, Youness [Université de Limoges, FR 3503 GEIST, EA 1069 “Laboratoire de Chimie des Substances Naturelles”, GDR CNRS 3049, Faculté de Pharmacie, Laboratoire de Biochimie et Biologie Moléculaire, 2 rue du Docteur Marcland, 87025 Limoges Cedex (France); Cook-Moreau, Jeanne [Université de Limoges, FR 3503 GEIST, UMR CNRS 7276 “Contrôle de la réponse immune B et lymphoproliférations”, Faculté de Médecine, 2 rue du Docteur Marcland, 87025 Limoges Cedex (France); Beneytout, Jean-Louis [Université de Limoges, FR 3503 GEIST, EA 1069 “Laboratoire de Chimie des Substances Naturelles”, GDR CNRS 3049, Faculté de Pharmacie, Laboratoire de Biochimie et Biologie Moléculaire, 2 rue du Docteur Marcland, 87025 Limoges Cedex (France); Liagre, Bertrand, E-mail: bertrand.liagre@unilim.fr [Université de Limoges, FR 3503 GEIST, EA 1069 “Laboratoire de Chimie des Substances Naturelles”, GDR CNRS 3049, Faculté de Pharmacie, Laboratoire de Biochimie et Biologie Moléculaire, 2 rue du Docteur Marcland, 87025 Limoges Cedex (France)

2013-04-15

Erythroleukemia is generally associated with a very poor response and survival to current available therapeutic agents. Cyclooxygenase-2 (COX-2) has been described to play a crucial role in the proliferation and differentiation of leukemia cells, this enzyme seems to play an important role in chemoresistance in different cancer types. Previously, we demonstrated that diosgenin, a plant steroid, induced apoptosis in HEL cells with concomitant COX-2 overexpression. In this study, we investigated the antiproliferative and apoptotic effects of cyclopamine and jervine, two steroidal alkaloids with similar structures, on HEL and TF1a human erythroleukemia cell lines and, for the first time, their effect on COX-2 expression. Cyclopamine, but not jervine, inhibited cell proliferation and induced apoptosis in these cells. Both compounds induced COX-2 overexpression which was responsible for apoptosis resistance. In jervine-treated cells, COX-2 overexpression was NF-κB dependent. Inhibition of NF-κB reduced COX-2 overexpression and induced apoptosis. In addition, cyclopamine induced apoptosis and COX-2 overexpression via PKC activation. Inhibition of the PKC pathway reduced both apoptosis and COX-2 overexpression in both cell lines. Furthermore, we demonstrated that the p38/COX-2 pathway was involved in resistance to cyclopamine-induced apoptosis since p38 inhibition reduced COX-2 overexpression and increased apoptosis in both cell lines. - Highlights: ► Cyclopamine alone but not jervine induces apoptosis in human erythroleukemia cells. ► Cyclopamine and jervine induce COX-2 overexpression. ► COX-2 overexpression is implicated in resistance to cyclopamine-induced apoptosis. ► Apoptotic potential of jervine is restrained by NF-κB pathway activation. ► PKC is involved in cyclopamine-induced apoptosis and COX-2 overexpression.

Cyclo-oxygenase(COX)-2-remming bij de preventie en de behandeling van colorectaal carcinoom

NARCIS (Netherlands)

Tuynman, J. B.; Hulscher, J. B.; Steller, E. Ph; van Lanschot, J. J.; Richel, D. J.

2003-01-01

Epidemiological studies have found that long-term use of non-steroidal anti-inflammatory drugs (NSAIDs) is associated with a lower risk of colorectal cancer (CRC). Cyclooxygenase (COX)-2 expression is present in colorectal cancer and overexpression is associated with metastases and poorer prognosis

Astrocyte-specific regulation of hMeCP2 expression in Drosophila

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David L. Hess-Homeier

2014-10-01

Full Text Available Alterations in the expression of Methyl-CpG-binding protein 2 (MeCP2 either by mutations or gene duplication leads to a wide spectrum of neurodevelopmental disorders including Rett Syndrome and MeCP2 duplication disorder. Common features of Rett Syndrome (RTT, MeCP2 duplication disorder, and neuropsychiatric disorders indicate that even moderate changes in MeCP2 protein levels result in functional and structural cell abnormalities. In this study, we investigated two areas of MeCP2 pathophysiology using Drosophila as a model system: the effects of MeCP2 glial gain-of-function activity on circuits controlling sleep behavior, and the cell-type specific regulation of MeCP2 expression. In this study, we first examined the effects of elevated MeCP2 levels on microcircuits by expressing human MeCP2 (hMeCP2 in astrocytes and distinct subsets of amine neurons including dopamine and octopamine (OA neurons. Depending on the cell-type, hMeCP2 expression reduced sleep levels, altered daytime/nighttime sleep patterns, and generated sleep maintenance deficits. Second, we identified a 498 base pair region of the MeCP2e2 isoform that is targeted for regulation in distinct subsets of astrocytes. Levels of the full-length hMeCP2e2 and mutant RTT R106W protein decreased in astrocytes in a temporally and spatially regulated manner. In contrast, expression of the deletion Δ166 hMeCP2 protein was not altered in the entire astrocyte population. qPCR experiments revealed a reduction in full-length hMeCP2e2 transcript levels suggesting transgenic hMeCP2 expression is regulated at the transcriptional level. Given the phenotypic complexities that are caused by alterations in MeCP2 levels, our results provide insight into distinct cellular mechanisms that control MeCP2 expression and link microcircuit abnormalities with defined behavioral deficits.

Inhibition of 5-LOX, COX-1, and COX-2 increases tendon healing and reduces muscle fibrosis and lipid accumulation after rotator cuff repair.

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Oak, Nikhil R; Gumucio, Jonathan P; Flood, Michael D; Saripalli, Anjali L; Davis, Max E; Harning, Julie A; Lynch, Evan B; Roche, Stuart M; Bedi, Asheesh; Mendias, Christopher L

2014-12-01

The repair and restoration of function after chronic rotator cuff tears are often complicated by muscle atrophy, fibrosis, and fatty degeneration of the diseased muscle. The inflammatory response has been implicated in the development of fatty degeneration after cuff injuries. Licofelone is a novel anti-inflammatory drug that inhibits 5-lipoxygenase (5-LOX), as well as cyclooxygenase (COX)-1 and COX-2 enzymes, which play important roles in inducing inflammation after injuries. While previous studies have demonstrated that nonsteroidal anti-inflammatory drugs and selective inhibitors of COX-2 (coxibs) may prevent the proper healing of muscles and tendons, studies about bone and cartilage have demonstrated that drugs that inhibit 5-LOX concurrently with COX-1 and COX-2 may enhance tissue regeneration. After the repair of a chronic rotator cuff tear in rats, licofelone would increase the load to failure of repaired tendons and increase the force production of muscle fibers. Controlled laboratory study. Rats underwent supraspinatus release followed by repair 28 days later. After repair, rats began a treatment regimen of either licofelone or a vehicle for 14 days, at which time animals were euthanized. Supraspinatus muscles and tendons were then subjected to contractile, mechanical, histological, and biochemical analyses. Compared with controls, licofelone-treated rats had a grossly apparent decrease in inflammation and increased fibrocartilage formation at the enthesis, along with a 62% increase in the maximum load to failure and a 51% increase in peak stress to failure. Licofelone resulted in a marked reduction in fibrosis and lipid content in supraspinatus muscles as well as reduced expression of several genes involved in fatty infiltration. Despite the decline in fibrosis and fat accumulation, muscle fiber specific force production was reduced by 23%. The postoperative treatment of cuff repair with licofelone may reduce fatty degeneration and enhance the development

The expression of proinflammatory genes in epidermal keratinocytes is regulated by hydration status.

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Xu, Wei; Jia, Shengxian; Xie, Ping; Zhong, Aimei; Galiano, Robert D; Mustoe, Thomas A; Hong, Seok J

2014-04-01

Mucosal wounds heal more rapidly, exhibit less inflammation, and are associated with minimal scarring when compared with equivalent cutaneous wounds. We previously demonstrated that cutaneous epithelium exhibits an exaggerated response to injury compared with mucosal epithelium. We hypothesized that treatment of injured skin with a semiocclusive dressing preserves the hydration of the skin and results in a wound healing phenotype that more closely resembles that of mucosa. Here we explored whether changes in hydration status alter epidermal gene expression patterns in rabbit partial-thickness incisional wounds. Using microarray studies on injured epidermis, we showed that global gene expression patterns in highly occluded versus non-occluded wounds are distinct. Many genes including IL-1β, IL-8, TNF-α (tumor necrosis factor-α), and COX-2 (cyclooxygenase 2) are upregulated in non-occluded wounds compared with highly occluded wounds. In addition, decreased levels of hydration resulted in an increased expression of proinflammatory genes in human ex vivo skin culture (HESC) and stratified keratinocytes. Hierarchical analysis of genes using RNA interference showed that both TNF-α and IL-1β regulate the expression of IL-8 through independent pathways in response to reduced hydration. Furthermore, both gene knockdown and pharmacological inhibition studies showed that COX-2 mediates the TNF-α/IL-8 pathway by increasing the production of prostaglandin E2 (PGE2). IL-8 in turn controls the production of matrix metalloproteinase-9 in keratinocytes. Our data show that hydration status directly affects the expression of inflammatory signaling in the epidermis. The identification of genes involved in the epithelial hydration pathway provides an opportunity to develop strategies to reduce scarring and optimize wound healing.

Cannabinoids Regulate Bcl-2 and Cyclin D2 Expression in Pancreatic β Cells.

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Jihye Kim

Full Text Available Recent reports have shown that cannabinoid 1 receptors (CB1Rs are expressed in pancreatic β cells, where they induce cell death and cell cycle arrest by directly inhibiting insulin receptor activation. Here, we report that CB1Rs regulate the expression of the anti-apoptotic protein Bcl-2 and cell cycle regulator cyclin D2 in pancreatic β cells. Treatment of MIN6 and βTC6 cells with a synthetic CB1R agonist, WIN55,212-2, led to a decrease in the expression of Bcl-2 and cyclin D2, in turn inducing cell cycle arrest in G0/G1 phase and caspase-3-dependent apoptosis. Additionally, genetic deletion and pharmacological blockade of CB1Rs after injury in mice led to increased levels of Bcl-2 and cyclin D2 in pancreatic β cells. These findings provide evidence for the involvement of Bcl-2 and cyclin D2 mediated by CB1Rs in the regulation of β-cell survival and growth, and will serve as a basis for developing new therapeutic interventions to enhance β-cell function and growth in diabetes.

Enhancement of ATRA-induced differentiation of neuroblastoma cells with LOX/COX inhibitors: an expression profiling study.

Science.gov (United States)

Chlapek, Petr; Redova, Martina; Zitterbart, Karel; Hermanova, Marketa; Sterba, Jaroslav; Veselska, Renata

2010-05-11

We performed expression profiling of two neuroblastoma cell lines, SK-N-BE(2) and SH-SY5Y, after combined treatment with all-trans retinoic acid (ATRA) and inhibitors of lipoxygenases (LOX) and cyclooxygenases (COX). This study is a continuation of our previous work confirming the possibility of enhancing ATRA-induced cell differentiation in these cell lines by the application of LOX/COX inhibitors and brings more detailed information concerning the mechanisms of the enhancement of ATRA-induced differentiation of neuroblastoma cells. Caffeic acid, as an inhibitor of 5-lipoxygenase, and celecoxib, as an inhibitor on cyclooxygenase-2, were used in this study. Expression profiling was performed using Human Cancer Oligo GEArray membranes that cover 440 cancer-related genes. Cluster analyses of the changes in gene expression showed the concentration-dependent increase in genes known to be involved in the process of retinoid-induced neuronal differentiation, especially in cytoskeleton remodeling. These changes were detected in both cell lines, and they were independent of the type of specific inhibitors, suggesting a common mechanism of ATRA-induced differentiation enhancement. Furthermore, we also found overexpression of some genes in the same cell line (SK-N-BE(2) or SH-SY5Y) after combined treatment with both ATRA and CA, or ATRA and CX. Finally, we also detected that gene expression was changed after treatment with the same inhibitor (CA or CX) in combination with ATRA in both cell lines. Obtained results confirmed our initial hypothesis of the common mechanism of enhancement in ATRA-induced cell differentiation via inhibition of arachidonic acid metabolic pathway.

Neuroprotective effects of curcumin alleviate lumbar intervertebral disc degeneration through regulating the expression of iNOS, COX‑2, TGF‑β1/2, MMP‑9 and BDNF in a rat model.

Science.gov (United States)

Hu, Yuan; Tang, Jin-Shu; Hou, Shu-Xun; Shi, Xiu-Xiu; Qin, Jiang; Zhang, Tie-Song; Wang, Xiao-Jing

2017-11-01

Curcumin is a natural product with antimutagenic, antitumor, antioxidant and neuroprotective properties. However, to the best of our knowledge, curcumin has yet to be investigated for the treatment of lumbar intervertebral disc degeneration LIDD). The aim of the present study was to investigate whether curcumin can alleviate LIDD through regulating the expression of inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)‑2, transforming growth factor (TGF)‑β1/2, matrix metalloproteinase (MMP)‑9 and brain‑derived neurotrophic factor (BDNF) in a rat model of LIDD. The results of the present study suggest that pretreatment with curcumin can prevent the development of LIDD in rats. It was revealed that treatment with curcumin significantly reduced interleukin (IL)‑1β and IL‑6, iNOS, COX‑2 and MMP‑9 levels in rats with LIDD. In addition, treatment with curcumin reduced the mRNA expression levels of TGF‑β1 and TGF‑β2, whereas it increased the mRNA expression levels of BDNF in rats with LIDD. In conclusion, the present findings indicate that curcumin may exert protective effects on LIDD development, exerting its action through the regulation of iNOS, COX‑2, TGF‑β1/2, MMP‑9 and BDNF.

Hemin inhibits cyclooxygenase-2 expression through nuclear factor-kappa B activation and ornithine decarboxylase expression in 12-O-tetradecanoylphorbol-13-acetate-treated mouse skin

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Park, Jae Hee; Lee, Chang Ki [Department of Oral Biology, Yonsei University College of Dentistry, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul 120-752 (Korea, Republic of); Oral Cancer Research Institute, Yonsei University College of Dentistry, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul 120-752 (Korea, Republic of); Hwang, Young Sun [Department of Applied Life Science and Brain Korea 21 Project, Yonsei University College of Dentistry, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul 120-752 (Korea, Republic of); Park, Kwang-Kyun [Department of Oral Biology, Yonsei University College of Dentistry, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul 120-752 (Korea, Republic of); Department of Applied Life Science and Brain Korea 21 Project, Yonsei University College of Dentistry, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul 120-752 (Korea, Republic of); Chung, Won-Yoon [Department of Oral Biology, Yonsei University College of Dentistry, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul 120-752 (Korea, Republic of); Department of Applied Life Science and Brain Korea 21 Project, Yonsei University College of Dentistry, 134 Shinchon-Dong, Seodaemoon-Ku, Seoul 120-752 (Korea, Republic of)], E-mail: wychung@yuhs.ac

2008-07-03

Inflammation induced by various stimuli has been found to be associated with increased risk for most types of human cancer. Inflammation facilitates the initiation of normal cells, as well as the growth of initiated cells and their progression to malignancy through production of proinflammatory cytokines and diverse reactive oxygen/nitrogen species. These also activate the signaling molecules that are involved in inflammation and carcinogenesis. Our previous studies have demonstrated that hemin inhibited 7,12-dimethylbenz[a]anthracene (DMBA)-induced bacterial mutagenesis and oxidative DNA damage, reduced the level of DNA-DMBA adduct and 12-O-tetradecanoylphorobl-13-acetate (TPA)-induced tumor formation in DMBA-initiated ICR mouse skin, and inhibited myeloperoxidase and ornithine decarboxylase (ODC) activity and H{sub 2}O{sub 2} formation in TPA-treated mouse skin. In the present study, to further elucidate the molecular mechanisms underlying the chemopreventive activity of hemin, its effect on the expression of ODC and cyclooxygenase (COX)-2, and the activation of nuclear factor-kappa B (NF-{kappa}B) and mitogen-activated protein kinases (MAPKs) regulating these proteins were explored in mouse skin with TPA-induced inflammation. Topically applied hemin inhibited ear edema and epidermal thickness in mice treated with TPA. Pretreatment with hemin reduced the expression of ODC and COX-2, and also reduced NF-{kappa}B activation in TPA-stimulated mouse skin. In addition, hemin suppressed the TPA-induced activation of extracellular signal-regulated protein kinase (ERK) and p38 MAPK in a dose-dependent manner. Taken together, hemin inhibited TPA-induced COX-2 expression by altering NF-{kappa}B signaling pathway via ERK and p38 MAPK, as well as TPA-induced ODC expression in mouse skin. Thereby, hemin may be an attractive candidate for a chemopreventive agent.

Hemin inhibits cyclooxygenase-2 expression through nuclear factor-kappa B activation and ornithine decarboxylase expression in 12-O-tetradecanoylphorbol-13-acetate-treated mouse skin

International Nuclear Information System (INIS)

Park, Jae Hee; Lee, Chang Ki; Hwang, Young Sun; Park, Kwang-Kyun; Chung, Won-Yoon

2008-01-01

Inflammation induced by various stimuli has been found to be associated with increased risk for most types of human cancer. Inflammation facilitates the initiation of normal cells, as well as the growth of initiated cells and their progression to malignancy through production of proinflammatory cytokines and diverse reactive oxygen/nitrogen species. These also activate the signaling molecules that are involved in inflammation and carcinogenesis. Our previous studies have demonstrated that hemin inhibited 7,12-dimethylbenz[a]anthracene (DMBA)-induced bacterial mutagenesis and oxidative DNA damage, reduced the level of DNA-DMBA adduct and 12-O-tetradecanoylphorobl-13-acetate (TPA)-induced tumor formation in DMBA-initiated ICR mouse skin, and inhibited myeloperoxidase and ornithine decarboxylase (ODC) activity and H 2 O 2 formation in TPA-treated mouse skin. In the present study, to further elucidate the molecular mechanisms underlying the chemopreventive activity of hemin, its effect on the expression of ODC and cyclooxygenase (COX)-2, and the activation of nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinases (MAPKs) regulating these proteins were explored in mouse skin with TPA-induced inflammation. Topically applied hemin inhibited ear edema and epidermal thickness in mice treated with TPA. Pretreatment with hemin reduced the expression of ODC and COX-2, and also reduced NF-κB activation in TPA-stimulated mouse skin. In addition, hemin suppressed the TPA-induced activation of extracellular signal-regulated protein kinase (ERK) and p38 MAPK in a dose-dependent manner. Taken together, hemin inhibited TPA-induced COX-2 expression by altering NF-κB signaling pathway via ERK and p38 MAPK, as well as TPA-induced ODC expression in mouse skin. Thereby, hemin may be an attractive candidate for a chemopreventive agent

HOXB4 Gene Expression Is Regulated by CDX2 in Intestinal Epithelial Cells

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Jørgensen, Steffen; Coshun, Mehmet; Mikkelsen Homburg, Keld

2016-01-01

analysis and expression data from Caco2 cells also suggests a role for CDX2 in the regulation of HOXB4 gene expression in the intestinal epithelium. Thus, the aim of this study was to investigate whether HOXB4 gene expression is regulated by CDX2 in the intestinal epithelium. We demonstrated binding of CDX......The mammalian Caudal-related homeobox transcription factor 2 (CDX2) plays a key role in the homeobox regulatory network and is essential in regulating the expression of several homeobox (HOX) genes during embryonic development, particularly in the gut. Genome-wide CDX2 chromatin immunoprecipitation......2 to four different CDX2 binding sites in an enhancer region located upstream of the HOXB4 transcription start site. Mutations in the CDX2 binding sites reduced HOXB4 gene activity, and knock down of endogenous CDX2 expression by shRNA reduced HOXB4 gene expression. This is the first report...

Poly-γ-Glutamic Acid Induces Apoptosis via Reduction of COX-2 Expression in TPA-Induced HT-29 Human Colorectal Cancer Cells

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Eun Ju Shin

2015-04-01

Full Text Available Poly-γ-glutamic acid (PGA is one of the bioactive compounds found in cheonggukjang, a fast-fermented soybean paste widely utilized in Korean cooking. PGA is reported to have a number of beneficial health effects, and interestingly, it has been identified as a possible anti-cancer compound through its ability to promote apoptosis in cancer cells, although the precise molecular mechanisms remain unclear. Our findings demonstrate that PGA inhibits the pro-proliferative functions of the phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA, a known chemical carcinogen in HT-29 human colorectal cancer cells. This inhibition was accompanied by hallmark apoptotic phenotypes, including DNA fragmentation and the cleavage of poly (ADP-ribose polymerase (PARP and caspase 3. In addition, PGA treatment reduced the expression of genes known to be overexpressed in colorectal cancer cells, including cyclooxygenase 2 (COX-2 and inducible nitric oxide synthase (iNOS. Lastly, PGA promoted activation of 5' adenosine monophosphate-activated protein (AMPK in HT-29 cells. Taken together, our results suggest that PGA treatment enhances apoptosis in colorectal cancer cells, in part by modulating the activity of the COX-2 and AMPK signaling pathways. These anti-cancer functions of PGA make it a promising compound for future study.

Rapamycin down-regulates LDL-receptor expression independently of SREBP-2

International Nuclear Information System (INIS)

Sharpe, Laura J.; Brown, Andrew J.

2008-01-01

As a key regulator of cholesterol homeostasis, sterol-regulatory element binding protein-2 (SREBP-2) up-regulates expression of genes involved in cholesterol synthesis (e.g., 3-hydroxy-3-methyl-glutaryl-coenzyme A (HMG-CoA) Reductase) and uptake (the low density lipoprotein (LDL)-receptor). Previously, we showed that Akt, a critical kinase in cell growth and proliferation, contributes to SREBP-2 activation. However, the specific Akt target involved is unknown. A potential candidate is the mammalian target of rapamycin, mTOR. Rapamycin can cause hyperlipidaemia clinically, and we hypothesised that this may be mediated via an effect of mTOR on SREBP-2. Herein, we found that SREBP-2 activation and HMG-CoA Reductase gene expression were unaffected by rapamycin treatment. However, LDL-receptor gene expression was decreased by rapamycin, suggesting that this may contribute to the hyperlipidaemia observed in rapamycin-treated patients. Rapamycin did not affect mRNA stability, so the decrease in LDL-receptor gene expression is likely to be occurring at the transcriptional level, although independently of SREBP-2

Exploring selectivity requirements for COX-2 versus COX-1 binding of 2-(5-phenyl-pyrazol-1-yl)-5-methanesulfonylpyridines using topological and physico-chemical parameters.

Science.gov (United States)

Chakraborty, Santanu; Sengupta, Chandana; Roy, Kunal

2005-04-01

Considering the current need for development of selective cyclooxygenase-2 (COX-2) inhibitors, an attempt has been made to explore physico-chemical requirements of 2-(5-phenyl-pyrazol-1-yl)-5-methanesulfonylpyridines for binding with COX-1 and COX-2 enzyme subtypes and also to explore the selectivity requirements. In this study, E-states of different common atoms of the molecules (calculated according to Kier & Hall), first order valence connectivity and physicochemical parameters (hydrophobicity pi, Hammett sigma and molar refractivity MR of different ring substituents) were used as independent variables along with suitable dummy parameters in the stepwise regression method. The best equation describing COX-1 binding affinity [n = 25, Q2 = 0.606, R(a)2 = 0.702, R2 = 0.752, R = 0.867, s = 0.447, F = 15.2 (df 4, 20)] suggests that the COX-1 binding affinity increases in the presence of a halogen substituent at R1 position and a p-alkoxy or p-methylthio substituent at R2 position. Furthermore, a difluoromethyl group is preferred over a trifluoromethyl group at R position for the COX-1 binding. The best equation describing COX-2 binding affinity [n = 32, Q2 = 0.622, R(a)2= 0.692, R2 = 0.732, R = 0.856, s = 0.265, F = 18.4 (df 4, 27)] shows that the COX-2 binding affinity increases with the presence of a halogen substituent at R1 position and increase of size of R2 substituents. However, it decreases in case of simultaneous presence of 3-chloro and 4-methoxy groups on the phenyl nucleus and in the presence of highly lipophilic R2 substituents. The best selectivity relation [n = 25, Q2 = 0.455, R(a)2 = 0.605, R2 = 0.670, R = 0.819, s = 0.423, F = 10.2 (df 4, 20)] suggests that the COX-2 selectivity decreases in the presence of p-alkoxy group and electron-withdrawing para substituents at R2 position. Again, a trifluoro group is conductive for the selectivity instead of a difluoromethyl group at R position. Furthermore, branching may also play significant role in

Curcumin inhibits interferon-α induced NF-κB and COX-2 in human A549 non-small cell lung cancer cells

International Nuclear Information System (INIS)

Lee, Jeeyun; Im, Young-Hyuck; Jung, Hae Hyun; Kim, Joo Hyun; Park, Joon Oh; Kim, Kihyun; Kim, Won Seog; Ahn, Jin Seok; Jung, Chul Won; Park, Young Suk; Kang, Won Ki; Park, Keunchil

2005-01-01

The A549 cells, non-small cell lung cancer cell line from human, were resistant to interferon (IFN)-α treatment. The IFN-α-treated A549 cells showed increase in protein expression levels of NF-κB and COX-2. IFN-α induced NF-κB binding activity within 30 min and this increased binding activity was markedly suppressed with inclusion of curcumin. Curcumin also inhibited IFN-α-induced COX-2 expression in A549 cells. Within 10 min, IFN-α rapidly induced the binding activity of a γ- 32 P-labeled consensus GAS oligonucleotide probe, which was profoundly reversed by curcumin. Taken together, IFN-α-induced activations of NF-κB and COX-2 were inhibited by the addition of curcumin in A549 cells

Effect of brain-derived neurotrophic factor on activity-regulated cytoskeleton-associated protein gene expression in primary frontal cortical neurons. Comparison with NMDA and AMPA

DEFF Research Database (Denmark)

El-Sayed, Mona; Hofman-Bang, Jacob; Mikkelsen, Jens D

2011-01-01

The effect of brain-derived neurotrophic factor (BDNF) on activity-regulated cytoskeleton-associated protein (Arc) mRNA levels in primary neuronal cultures of rat frontal cortex was characterized pharmacologically and compared to the effect on expression of c-fos, bdnf, neuritin, cox-2 as examples...

Mechanisms of ceramide-induced COX-2-dependent apoptosis in human ovarian cancer OVCAR-3 cells partially overlapped with resveratrol

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Lin, Hung-Yun; Delmas, Dominique; Vang, Ole

2013-01-01

-2 appears at the apex of the p38 kinase-mediated signaling cascade induced by ceramide. Induction of apoptosis by ceramide or resveratrol was inhibited by the endocytosis inhibitor, cytochalasin D (CytD); however, cells exposed to resveratrol showed greater sensitivity than ceramide-treated cells....... Ceramide-treated cells underwent a dose-dependent reduction in trans-membrane potential. Although both ceramide and resveratrol induced the expressions of caspase-3 and -7, the effect of inducible COX-2 was different in caspase-7 expression induced by ceramide compared to resveratrol. In summary......, resveratrol and ceramide converge on an endocytosis-requiring, ERK1/2-dependent signal transduction pathway and induction of COX-expression as an essential molecular antecedent for subsequent p53-dependent apoptosis. In addition, expressions of caspase-3 and -7 are observed. However, a p38 kinase...

ERK1/2 mediates glucose-regulated POMC gene expression in hypothalamic neurons.

Science.gov (United States)

Zhang, Juan; Zhou, Yunting; Chen, Cheng; Yu, Feiyuan; Wang, Yun; Gu, Jiang; Ma, Lian; Ho, Guyu

2015-04-01

Hypothalamic glucose-sensing neurons regulate the expression of genes encoding feeding-related neuropetides POMC, AgRP, and NPY - the key components governing metabolic homeostasis. AMP-activated protein kinase (AMPK) is postulated to be the molecular mediator relaying glucose signals to regulate the expression of these neuropeptides. Whether other signaling mediator(s) plays a role is not clear. In this study, we investigated the role of ERK1/2 using primary hypothalamic neurons as the model system. The primary neurons were differentiated from hypothalamic progenitor cells. The differentiated neurons possessed the characteristic neuronal cell morphology and expressed neuronal post-mitotic markers as well as leptin-regulated orexigenic POMC and anorexigenic AgRP/NPY genes. Treatment of cells with glucose dose-dependently increased POMC and decreased AgRP/NPY expression with a concurrent suppression of AMPK phosphorylation. In addition, glucose treatment dose-dependently increased the ERK1/2 phosphorylation. Blockade of ERK1/2 activity with its specific inhibitor PD98059 partially (approximately 50%) abolished glucose-induced POMC expression, but had little effect on AgRP/NPY expression. Conversely, blockade of AMPK activity with its specific inhibitor produced a partial (approximately 50%) reversion of low-glucose-suppressed POMC expression, but almost completely blunted the low-glucose-induced AgRP/NPY expression. The results indicate that ERK1/2 mediated POMC but not AgRP/NPY expression. Confirming the in vitro findings, i.c.v. administration of PD98059 in rats similarly attenuated glucose-induced POMC expression in the hypothalamus, but again had little effect on AgRP/NPY expression. The results are indicative of a novel role of ERK1/2 in glucose-regulated POMC expression and offer new mechanistic insights into hypothalamic glucose sensing. © 2015 Society for Endocrinology.

The spatial expression and regulation of transcription factors IDEF1 and IDEF2

Science.gov (United States)

Kobayashi, Takanori; Ogo, Yuko; Aung, May Sann; Nozoye, Tomoko; Itai, Reiko Nakanishi; Nakanishi, Hiromi; Yamakawa, Takashi; Nishizawa, Naoko K.

2010-01-01

Background and Aims Under conditions of low iron availability, rice plants induce genes involved in iron uptake and utilization. The iron deficiency-responsive cis-acting element binding factors 1 and 2 (IDEF1 and IDEF2) regulate transcriptional response to iron deficiency in rice roots. Clarification of the functions of IDEF1 and IDEF2 could uncover the gene regulation mechanism. Methods Spatial patterns of IDEF1 and IDEF2 expression were analysed by histochemical staining of IDEF1 and IDEF2 promoter-GUS transgenic rice lines. Expression patterns of the target genes of IDEF1 and IDEF2 were analysed using transformants with induced or repressed expression of IDEF1 or IDEF2 grown in iron-rich or in iron-deficient solutions for 1 d. Key Results IDEF1 and IDEF2 were highly expressed in the basal parts of the lateral roots and vascular bundles. IDEF1 and IDEF2 expression was dominant in leaf mesophyll and vascular cells, respectively. These expression patterns were similar under both iron-deficient and iron-sufficient conditions. IDEF1 was strongly expressed in pollen, ovaries, the aleurone layer and embryo. IDEF2 was expressed in pollen, ovaries and the dorsal vascular region of the endosperm. During seed germination, IDEF1 and IDEF2 were expressed in the endosperm and embryo. Expression of IDEF1 target genes was regulated in iron-rich roots similar to early iron-deficiency stages. In addition, the expression patterns of IDEF2 target genes were similar between iron-rich conditions and early or subsequent iron deficiency. Conclusions IDEF1 and IDEF2 are constitutively expressed during both vegetative and reproductive stages. The spatial expression patterns of IDEF1 and IDEF2 overlap with their target genes in restricted cell types, but not in all cells. The spatial expression patterns and gene regulation of IDEF1 and IDEF2 in roots are generally conserved under conditions of iron sufficiency and deficiency, suggesting complicated interactions with unknown factors for

Exploring QSAR with E-state index: selectivity requirements for COX-2 versus COX-1 binding of terphenyl methyl sulfones and sulfonamides.

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Chakraborty, Santanu; Sengupta, Chandana; Roy, Kunal

2004-09-20

An attempt has been made to explore selectivity requirements for cyclooxygenase-2 (COX-2) versus cyclooxygenase-1 (COX-1) binding of terphenyl methyl sulfones and sulfonamides using electrotopological state (E-state) index and suitable indicator parameters. Multiple linear regression analyses produced statistically acceptable equations: the best relation based on 'all-possible-subsets regression' for COX-1 binding (n=18) showed predicted variance and explained variance of 0.675 and 0.777, respectively, while in case of the best equation for COX-2 binding (n=38), these values rose to 0.842 and 0.874, respectively. For the selectivity relation (n=17), predicted variance and explained variance values were 0.601 and 0.687, respectively. Based on the results of the analyses, three important sites have been suggested: sites A (methylsulfonyl or aminosulfonyl moiety), B (central phenyl ring), and C (terminal phenyl ring containing different substituents). All three sites are important for COX-2 binding while sites B and C are important for COX-1 binding. For COX-2 selectivity, only site C plays an important role. The study shows the utility of E-state index in developing statistically acceptable model having direct physicochemical significance.

Enhancement of ATRA-induced differentiation of neuroblastoma cells with LOX/COX inhibitors: an expression profiling study

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Hermanova Marketa

2010-05-01

Full Text Available Abstract Background We performed expression profiling of two neuroblastoma cell lines, SK-N-BE(2 and SH-SY5Y, after combined treatment with all-trans retinoic acid (ATRA and inhibitors of lipoxygenases (LOX and cyclooxygenases (COX. This study is a continuation of our previous work confirming the possibility of enhancing ATRA-induced cell differentiation in these cell lines by the application of LOX/COX inhibitors and brings more detailed information concerning the mechanisms of the enhancement of ATRA-induced differentiation of neuroblastoma cells. Methods Caffeic acid, as an inhibitor of 5-lipoxygenase, and celecoxib, as an inhibitor on cyclooxygenase-2, were used in this study. Expression profiling was performed using Human Cancer Oligo GEArray membranes that cover 440 cancer-related genes. Results Cluster analyses of the changes in gene expression showed the concentration-dependent increase in genes known to be involved in the process of retinoid-induced neuronal differentiation, especially in cytoskeleton remodeling. These changes were detected in both cell lines, and they were independent of the type of specific inhibitors, suggesting a common mechanism of ATRA-induced differentiation enhancement. Furthermore, we also found overexpression of some genes in the same cell line (SK-N-BE(2 or SH-SY5Y after combined treatment with both ATRA and CA, or ATRA and CX. Finally, we also detected that gene expression was changed after treatment with the same inhibitor (CA or CX in combination with ATRA in both cell lines. Conclusions Obtained results confirmed our initial hypothesis of the common mechanism of enhancement in ATRA-induced cell differentiation via inhibition of arachidonic acid metabolic pathway.

Platelet cyclooxygenase expression in normal dogs.

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Thomason, J; Lunsford, K; Mullins, K; Stokes, J; Pinchuk, L; Wills, R; McLaughlin, R; Langston, C; Pruett, S; Mackin, A

2011-01-01

Human platelets express both cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2). Variation in COX-2 expression could be a mechanism for variable response to aspirin. The hypotheses were that circulating canine platelets express COX-1 and COX-2, and that aspirin alters COX expression. The objective was to identify changes in platelet COX expression and in platelet function caused by aspirin administration to dogs. Eight female, intact hounds. A single population, repeated measures design was used to evaluate platelet COX-1 and COX-2 expression by flow cytometry before and after aspirin (10 mg/kg Q12h for 10 days). Platelet function was analyzed via PFA-100(®) (collagen/epinephrine), and urine 11-dehydro-thromboxane B(2) (11-dTXB(2)) was measured and normalized to urinary creatinine. Differences in COX expression, PFA-100(®) closure times, and urine 11-dTXB(2 ): creatinine ratio were analyzed before and after aspirin administration. Both COX-1 and COX-2 were expressed in canine platelets. COX-1 mean fluorescent intensity (MFI) increased in all dogs, by 250% (range 63-476%), while COX-2 expression did not change significantly (P = 0.124) after aspirin exposure, with large interindividual variation. PFA-100(®) closure times were prolonged and urine 11-dTXB(2) concentration decreased in all dogs after aspirin administration. Canine platelets express both COX isoforms. After aspirin exposure, COX-1 expression increased despite impairment of platelet function, while COX-2 expression varied markedly among dogs. Variability in platelet COX-2 expression should be explored as a potential mechanism for, or marker of, variable aspirin responsiveness. Copyright © 2011 by the American College of Veterinary Internal Medicine.

Cyclooxygenase-2 Selectively Controls Renal Blood Flow Through a Novel PPARβ/δ-Dependent Vasodilator Pathway.

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Kirkby, Nicholas S; Sampaio, Walkyria; Etelvino, Gisele; Alves, Daniele T; Anders, Katie L; Temponi, Rafael; Shala, Fisnik; Nair, Anitha S; Ahmetaj-Shala, Blerina; Jiao, Jing; Herschman, Harvey R; Xiaomeng, Wang; Wahli, Walter; Santos, Robson A; Mitchell, Jane A

2018-02-01

Cyclooxygenase-2 (COX-2) is an inducible enzyme expressed in inflammation and cancer targeted by nonsteroidal anti-inflammatory drugs. COX-2 is also expressed constitutively in discreet locations where its inhibition drives gastrointestinal and cardiovascular/renal side effects. Constitutive COX-2 expression in the kidney regulates renal function and blood flow; however, the global relevance of the kidney versus other tissues to COX-2-dependent blood flow regulation is not known. Here, we used a microsphere deposition technique and pharmacological COX-2 inhibition to map the contribution of COX-2 to regional blood flow in mice and compared this to COX-2 expression patterns using luciferase reporter mice. Across all tissues studied, COX-2 inhibition altered blood flow predominantly in the kidney, with some effects also seen in the spleen, adipose, and testes. Of these sites, only the kidney displayed appreciable local COX-2 expression. As the main site where COX-2 regulates blood flow, we next analyzed the pathways involved in kidney vascular responses using a novel technique of video imaging small arteries in living tissue slices. We found that the protective effect of COX-2 on renal vascular function was associated with prostacyclin signaling through PPARβ/δ (peroxisome proliferator-activated receptor-β/δ). These data demonstrate the kidney as the principle site in the body where local COX-2 controls blood flow and identifies a previously unreported PPARβ/δ-mediated renal vasodilator pathway as the mechanism. These findings have direct relevance to the renal and cardiovascular side effects of drugs that inhibit COX-2, as well as the potential of the COX-2/prostacyclin/PPARβ/δ axis as a therapeutic target in renal disease. © 2018 The Authors.

NDRG2 inhibits hepatocellular carcinoma adhesion, migration and invasion by regulating CD24 expression

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Zheng, Jin; Guo, Hang; Tao, Yurong; Xue, Yan; Jiang, Ning; Yao, Libo; Liu, Wenchao; Li, Yan; Yang, Jiandong; Liu, Qiang; Shi, Ming; Zhang, Rui; Shi, Hengjun; Ren, Qinyou; Ma, Ji

2011-01-01

The prognosis of most hepatocellular carcinoma (HCC) patients is poor due to the high metastatic rate of the disease. Understanding the molecular mechanisms underlying HCC metastasis is extremely urgent. The role of CD24 and NDRG2 (N-myc downstream-regulated gene 2), a candidate tumor suppressor gene, has not yet been explored in HCC. The mRNA and protein expression of CD24 and NDRG2 was analyzed in MHCC97H, Huh7 and L-02 cells. Changes in cell adhesion, migration and invasion were detected by up- or down-regulating NDRG2 by adenovirus or siRNA. The expression pattern of NDRG2 and CD24 in HCC tissues and the relationship between NDRG2 and HCC clinical features was analyzed by immunohistochemical and western blotting analysis. NDRG2 expression was negatively correlated with malignancy in HCC. NDRG2 exerted anti-tumor activity by regulating CD24, a molecule that mediates cell-cell interaction, tumor proliferation and adhesion. NDRG2 up-regulation decreased CD24 expression and cell adhesion, migration and invasion. By contrast, NDRG2 down-regulation enhanced CD24 expression and cell adhesion, migration and invasion. Immunohistochemical analysis of 50 human HCC clinical specimens showed a strong correlation between NDRG2 down-regulation and CD24 overexpression (P = 0.04). In addition, increased frequency of NDRG2 down-regulation was observed in patients with elevated AFP serum level (P = 0.006), late TNM stage (P = 0.009), poor differentiation grade (P = 0.002), tumor invasion (P = 0.004) and recurrence (P = 0.024). Our findings indicate that NDRG2 and CD24 regulate HCC adhesion, migration and invasion. The expression level of NDRG2 is closely related to the clinical features of HCC. Thus, NDRG2 plays an important physiological role in HCC metastasis

Cyclooxygenase-2 Pathway Correlates with VEGF Expression in Head and Neck Cancer. Implications for Tumor Angiogenesis and Metastasis

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Oreste Gallo

2001-01-01

Full Text Available We evaluated the role of COX-2 pathway in 35 head and neck cancers (HNCs by analyzing COX-2 expression and prostaglandin E2 (PGE2 production in relation to tumor angiogenesis and lymph node metastasis. COX-2 activity was also correlated to vascular endothelial growth factor (VEGF mRNA and protein expression. COX-2 mRNA and protein expression was higher in tumor samples than in normal mucosa. PGE2 levels were higher in the tumor front zone in comparison with tumor core and normal mucosa (P<0001. Specimens from patients with lymph node metastasis exhibited higher COX-2 protein expression (P=.0074, PGEZ levels (P=.0011 and microvessel density (P<.0001 than specimens from patients without metastasis. A significant correlation between COX-2 and tumor vascularization (rs=0.450, P=.007 as well as between COX-2 and microvessel density with VEGF expression in tumor tissues was found (rs=0.450, P=.007; rs=0.620, P=.0001, respectively. The induction of COX-2 mRNA and PGE2 synthesis by EGF and Escherichia coli lipopolysaccharide (LPS in A-431 and SCC-9 cell lines, resulted in an increase in VEGF mRNA and protein production. Indomethacin and celecoxib reversed the EGF- and LPS-dependent COX-2, VEGF, and PGE2 increases. This study suggests a central role of COX-2 pathway in HNC angiogenesis by modulating VEGF production and indicates that COX-2 inhibitors may be useful in HNC treatment.

In vitro antiproliferative activity of 2,3-dihydroxy-9,10-anthraquinone induced apoptosis against COLO320 cells through cytochrome c release caspase mediated pathway with PI3K/AKT and COX-2 inhibition.

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Balachandran, C; Emi, N; Arun, Y; Yamamoto, N; Duraipandiyan, V; Inaguma, Yoko; Okamoto, Akinao; Ignacimuthu, S; Al-Dhabi, N A; Perumal, P T

2016-04-05

The present study investigated the anticancer activity of 2,3-dihydroxy-9,10-anthraquinone against different cancer cells such as MCF-7, COLO320, HepG-2, Skov-3, MOLM-14, NB-4, CEM, K562, Jurkat, HL-60, U937, IM-9 and Vero. 2,3-dihydroxy-9,10-anthraquinone showed good antiproliferative activity against COLO320 cells when compared to other tested cells. The cytotoxicity results showed 79.8% activity at the dose of 2.07 μM with IC50 value of 0.13 μM at 24 h in COLO320 cells. So we chose COLO320 cells for further anticancer studies. mRNA expression was confirmed by qPCR analysis using SYBR green method. Treatment with 2,3-dihydroxy-9,10-anthraquinone was found to trigger intrinsic apoptotic pathway as indicated by down regulation of Bcl-2, Bcl-xl; up regulation of Bim, Bax, Bad; release of cytochrome c and pro-caspases cleaving to caspases. Furthermore, 2,3-dihydroxy-9,10-anthraquinone stopped at G0/G1 phase with modulation in protein levels of cyclins. On the other hand PI3K/AKT signaling plays an important role in cell metabolism. We found that 2,3-dihydroxy-9,10-anthraquinone inhibits PI3K/AKT activity after treatment. Also, COX-2 enzyme plays a major role in colorectal cancer. Our results showed that the treatment significantly reduced COX-2 enzyme in COLO320 cells. These results indicated antiproliferative activity of 2,3-dihydroxy-9,10-anthraquinone involving apoptotic pathways, mitochondrial functions, cell cycle checkpoint and controlling the over expression genes during the colorectal cancer. Molecular docking studies showed that the compound bound stably to the active sites of Bcl-2, COX-2, PI3K and AKT. This is the first report of anticancer mechanism involving 2,3-dihydroxy-9,10-anthraquinone in COLO320 cells. The present results might provide helpful suggestions for the design of antitumor drugs toward colorectal cancer treatment. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Glucose-regulated protein 78 regulates the expression of mitochondrial genesis proteins in HBV-related hepatocellular carcinoma: a clinical analysis

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LI Yaping

2017-10-01

Full Text Available ObjectiveTo investigate the expression of glucose-regulated protein 78 (GRP78 in HBV-related hepatocellular carcinoma (HBV-HCC and its association with clinicopathological features, as well as its regulatory effect on mitochondrial genesis proteins in hepatoma cells, and to provide a basis for new strategies for the prevention and treatment of HCC. MethodsTissue samples were collected from 54 patients with HBV-HCC, and immunohistochemistry and Western blot were used to measure the expression of GRP78, Lon, TFAM, and cytochrome C oxidase Ⅳ (COXⅣ. The expression of GRP78 in hepatoma cells was interfered by siRNA, and then the expression of GRP78, Lon, mitochondrial transcription factor A (TFAM, and COX Ⅳ was measured. Quantitative real-time PCR was used to measure the level of mitochondrial DNA (mtDNA in clinical specimens and HCC cells after GRP78 expression was interfered with. A statistical analysis was performed for clinical and experimental data. The t-test was used for comparison of continuous data between groups, the Fisher′s exact test was used for comparison of categorical data between groups, and the Kaplan-Meier method was used for survival analysis. Results Compared with the adjacent tissues, HBV-HCC tissues had significantly higher expression of GRP78 and Lon (t=9.135 and 5523, both P＜0.0001 and significantly lower expression of the mitochondrial genesis proteins TFAM and COX Ⅳ and mtDNA level (t=2.765, 4260, and 12.280, P=0.011, ＜0.001, and ＜0.001. There were significant increases in the expression of the mitochondrial genesis proteins TFAM and COX Ⅳ and mtDNA level after the interference with GRP78 expression in hepatoma cells (all P＜0.05. There were significant differences in the expression of GRP78 between patients with different numbers of tumors, patients with and without portal vein tumor thrombus, and patients with different tumor stages (P=0.016， 0.003, and 0.045. The patients with low GRP78

Inhibition of p38/CREB phosphorylation and COX-2 expression by olive oil polyphenols underlies their anti-proliferative effects

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Corona, Giulia; Deiana, Monica; Incani, Alessandra; Vauzour, David; Assunta Dessi, M.; Spencer, Jeremy P.E.

2007-01-01

We investigated the anti-proliferative effects of an olive oil polyphenolic extract on human colon adenocarcinoma cells. Analysis indicated that the extract contained hydroxytyrosol, tyrosol and the various secoiridoid derivatives, including oleuropein. This extract exerted a strong inhibitory effect on cancer cell proliferation, which was linked to the induction of a G2/M phase cell cycle block. Following treatment with the extract (50 μg/ml) the number of cells in the G2/M phase increased to 51.82 ± 2.69% relative to control cells (15.1 ± 2.5%). This G2/M block was mediated by the ability of olive oil polyphenols (50 μg/ml) to exert rapid inhibition of p38 (38.7 ± 4.7%) and CREB (28.6 ± 5.5%) phosphorylation which led to a downstream reduction in COX-2 expression (56.9 ± 9.3%). Our data suggest that olive oil polyphenols may exert chemopreventative effects in the large intestine by interacting with signalling pathways responsible for colorectal cancer development

[Specific inhibitors of cyclooxygenase-2 (COX-2): current knowledge and perspectives].

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Rioda, W T; Nervetti, A

2001-01-01

The Authors summarize the current knowledge on a new class of nonsteroidal anti-inflammatory drugs (NSAIDs), the coxib (celecoxib and rofecoxib), in the treatment of rheumatic diseases. Celecoxib and rofecoxib are selective cyclooxygenase-2 (COX-2) inhibitors which possess the same anti-inflammatory and analgesic activities, but a better gastric tolerability compared to the non-selective COX-1 and COX-2 inhibitors. The Authors also report other possible therapeutic effects of these NSADIs as evidenced by the more recent data of the literature. Celecoxib seems to reduce the incidence of new polyps in patients with familial adenomatous polyposis. It has been suggested the use of celecoxib as a protective drug against the development of colorectal cancer. Other (neoplastic) or pre-neoplastic conditions, such as bladder dysplasia, Barret esophagus, attinic keratosis and Alzheimer's disease seem to have benefit from this class of drugs.

Synthesis and evaluation of ortho-[18F]fluorocelecoxib for COX-2 cholangiocarcinoma imaging

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Chang CW

2018-05-01

Full Text Available Chi-Wei Chang,1,* Chun-Nan Yeh,2,* Yi-Hsiu Chung,3,* Yong-Ren Chen,4 Shi-Wei Tien,4 Tsung-Wen Chen,2 Shiou-Shiow Farn,4,5 Ying-Cheng Huang,6 Chung-Shan Yu4,7 1Department of Nuclear Medicine, Taipei Veterans General Hospital, Taipei, Taiwan; 2Department of Surgery, Liver Research Center, Chang-Gung Memorial Hospital at Linkou, Chang Gung University, Taoyuan, Taiwan; 3Center for Advanced Molecular Imaging and Translation, Chang Gung Memorial Hospital, Taoyuan, Taiwan; 4Department of Biomedical Engineering and Environmental Sciences, National Tsinghua University, Hsinchu, Taiwan; 5Isotope Application Division, Institute of Nuclear Energy Research, Taoyuan, Taiwan; 6Department of Neurosurgery, Chang-Gung Memorial Hospital at Linkou, Chang Gung University, Taoyuan, Taiwan; 7Institute of Nuclear Engineering and Science, National Tsinghua University, Hsinchu, Taiwan *These authors contributed equally to this work Background: An 18F-tagged NSAID analog was prepared for use as a probe for COX-2 expression, which is associated with tumor development. Methods: The in vivo uptake of celecoxib was monitored with ortho-[18F]fluorocelecoxib using positron emission tomography (PET. The binding affinity of ortho-[18F]fluorocelecoxib to COX-1 and COX-2 enzymes were assessed using the competitor celecoxib. Results: The IC50 values were 0.039 μM and 0.024 μM, respectively. A selectivity index of 1.63 was obtained (COX-2 vs COX-1. COX-2 overexpressed cholangiocarcinoma (CCA murine cells took up more ortho-[18F]fluorocelecoxib than that by usual CCA cells from 10 to 60 minutes post incubation. Competitive inhibition (blocking of the tracer uptake of ortho-[18F]fluorocelecoxib in the presence of celecoxib by the COX-2 overexpressed CCA cells and the usual CCA cells gave the IC50 values of 0.5 μM and 46.5 μM, respectively. Based on the in vitro accumulation data and in vivo metabolism half-life (30 min, PET scanning was performed 30–60 min after the

Nutmeg oil alleviates chronic inflammatory pain through inhibition of COX-2 expression and substance P release in vivo

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Wei Kevin Zhang

2016-04-01

Full Text Available Background: Chronic pain, or sometimes referred to as persistent pain, reduces the life quality of patients who are suffering from chronic diseases such as inflammatory diseases, cancer and diabetes. Hence, herbal medicines draw many attentions and have been shown effective in the treatment or relief of pain. Methods and Results: Here in this study, we used the CFA-injected rats as a sustainable pain model to test the anti-inflammatory and analgesic effect of nutmeg oil, a spice flavor additive to beverages and baked goods produced from the seed of Myristica fragrans tree. Conclusions: We have demonstrated that nutmeg oil could potentially alleviate the CFA-injection induced joint swelling, mechanical allodynia and heat hyperanalgesia of rats through inhibition of COX-2 expression and blood substance P level, which made it possible for nutmeg oil to be a potential chronic pain reliever.

Growth and adherence of Staphylococcus aureus were enhanced through the PGE2 produced by the activated COX-2/PGE2 pathway of infected oral epithelial cells.

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Yuxia Wang

Full Text Available Staphylococcus aureus is a major pathogen of varieties of oral mucous infection. Prostaglandin E2 (PGE2 is a pro-inflammatory factor and Cyclooxygenase 2 (COX-2 is a critical enzyme of PGE2 biosynthesis. The purpose of this study is to investigate whether Staphylococcus aureus can increase PGE2 production of oral epithelial cells and how PGE2 functions in the growth and adherence of Staphylococcus aureus. mRNA levels of COX-2, fnbpA and fnbpB were estimated by quantitative PCR. PGE2 production was measured by Enzyme Linked Immunosorbent Assay (ELISA. The binding biomass of Staphylococcus aureus to human fibronectin was investigated by crystal violet staining and confocal laser scanning microscopy and the adherent force was measured by atomic force microscope (AFM. The COX-2 mRNA level and PGE2 production were increased by Staphylococcus aureus. PGE2 promoted the growth and biofilm formation of Staphylococcus aureus, enhanced the attachment of Staphylococcus aureus to the human fibronectin as well as to the HOK cells. The transcription of fnbpB was up-regulated by PGE2 in both early and middle exponential phase but not fnbpA. These results suggest that the activation of COX-2/PGE2 pathway in oral epithelial cell by Staphylococcus aureus can in turn facilitate the growth and the ability to adhere of the pathogen. These findings uncover a new function of PGE2 and may lead to the potential of COX-2/PGE2 targeting in the therapy of inflammation and cancer in both which the COX-2/PGE2 pathway were observed activated.

Wine polyphenols exert antineoplasic effect on androgen resistant PC-3 cell line through the inhibition of the transcriptional activity of COX-2 promoter mediated by NF-kβ.

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Ferruelo, A; de Las Heras, M M; Redondo, C; Ramón de Fata, F; Romero, I; Angulo, J C

2014-09-01

Mediterranean diet may play a role in the prevention of prostate cancer (PCa) development and progression. Cyclooxygenase-2 (COX-2) expression is associated with increased cellular proliferation, prevents apoptosis and favors tumor invasion. We intend to clarify whether resveratrol and other polyphenols effectively inhibit COX-2 activity and induce apoptosis in hormone-resistant PC-3 cell line. PC-3 cells were cultured and treated with different concentrations of gallic acid, tannic acid, quercetin, and resveratrol in presence of phorbol myristate acetate (PMA; 50 μg/ml) that induces COX-2 expression. Total RNA was extracted and COX-2 expression was analyzed by relative quantification real-time PCR (ΔΔCt method). COX-2 activity was determined by PGE-2 detection using ELISA. Caspase 3/7 luminescence assay was used to disclose apoptosis. Transitory transfection with short human COX-2 (phPES2 -327/+59) and p5xNF-kβ-Luc plasmids determined COX-2 promoter activity and specifically that dependant of NF-kβ. COX-2 expression was not modified in media devoid of PMA. However, under PMA induction tannic acid (2.08 ±.21), gallic acid (2.46 ±.16), quercetin (1.78 ±.14) and resveratrol (1.15 ±.16) significantly inhibited COX-2 mRNA with respect to control (3.14 ±.07), what means a 34%, 23%, 46% and 61% reduction, respectively. The inhibition in the levels of PGE-2 followed a similar pattern. All compounds studied induced apoptosis at 48 h, although at a different rate. PMA caused a rise in activity 7.4 ±.23 times phPES2 -327/+59 and 2.0 ±.1 times p5xNF-kβ-Luc at 6h compared to basal. Resveratrol suppressed these effects 17.1 ±.21 and 32.4 ±.18 times, respectively. Similarly, but to a lesser extent, the rest of evaluated polyphenols diminished PMA inductor effect on the activity of both promoters. Polyphenols inhibit transcriptional activity of COX-2 promoter mediated by NF-kβ. This effect could explain, at least in part, the induction of apoptosis in vitro by

Clinical significance of cyclooxygenase-2 expression in extranodal natural killer (NK)/T-cell lymphoma, nasal type

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Shim, Su Jung; Yang, Woo-Ick; Shin, Eunah; Koom, Woong Sub; Kim, Yong Bae; Cho, Jae Ho; Suh, Chang Ok; Kim, Joo Hang; Kim, Gwi Eon

2007-01-01

Purpose: To determine whether there are any differences in therapeutic response, patterns of systemic recurrence, and prognosis of patients with extranodal natural killer (NK)/T-cell lymphoma, nasal type, by the cyclooxygenase-2 (COX-2) expression. Patients and Methods: Thirty-four patients with Ann Arbor Stage I and II extranodal NK/T-cell lymphoma who underwent chemotherapy or radiotherapy, or both, were retrospectively reviewed. These patients were divided into two groups according to their immunohistochemical staining for COX-2 expressions: a COX-2-negative group (n = 10 patients) and a COX-2-positive group (n = 24 patients). The treatment response, patterns of treatment failure, and survival data for the patients were compared between the COX-2-positive and negative groups. Results: There was no significant difference in the clinical profiles between the COX-2-negative and COX-2-positive groups. All patients (100%) in the COX-2-negative group achieved complete response after initial treatment, whereas only 14 patients (58%) in the COX-2-positive group achieved complete response (p = 0.03). Compared with the patients in the COX-2-negative group, those in the COX-2-positive group had a significantly lower 2-year systemic recurrence-free survival rate (100% for the COX-2-negative group vs. 54% for the COX-2-positive group) (p = 0.02) and a decreased 5-year overall survival rate (70% for the COX-2-negative group vs. 32% for the COX-2-positive group) (p = 0.06). Conclusion: Cyclooxygenase-2 expression can serve as a predictive factor for poor treatment response, higher systemic recurrence, and unfavorable prognosis in patients with extranodal NK/T-cell lymphoma, nasal type

Stromal Expression of Hypoxia Regulated Proteins Is an Adverse Prognostic Factor in Colorectal Carcinomas

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Arjen H. G. Cleven

2007-01-01

Full Text Available Background: Hypoxia modifies the phenotype of tumors in a way that promotes tumor aggressiveness and resistance towards chemotherapy and radiotherapy. However, the expression and influence of hypoxia-regulated proteins on tumor biology are not well characterized in colorectal tumors. We studied the role of protein expression of hypoxia-inducible factor (HIF-1α, HIF-2α, carbonic anhydrase 9 (CA9 and glucose transporter 1 (GLUT1 in patients with colorectal adenocarcinomas. Methods: Expression of HIF-1α, HIF-2α, CA9 and GLUT1 was quantified by immunohistochemistry in 133 colorectal adenocarcinomas. The expression of hypoxia markers was correlated with clinicopathological variables and overall patient survival. Results: Expression of these hypoxia markers was detected in the epithelial compartment of the tumor cells as well as in tumor-associated stromal cells. Although tumor cells frequently showed expression of one or more of the investigated hypoxia markers, no correlation among these markers or with clinical response was found. However, within the tumor stroma, positive correlations between the hypoxia markers HIF-2α, CA9 and GLUT1 were observed. Furthermore expression of HIF-2α and CA9 in tumor-associated stroma were both associated with a significantly reduced overall survival. In the Cox proportional hazard model, stromal HIF-2α expression was an independent prognostic factor for survival. Conclusion: These observations show, that expression of hypoxia regulated proteins in tumor-associated stromal cells, as opposed to their expression in epithelial tumor cells, is associated with poor outcome in colorectal cancer. This study suggests that tumor hypoxia may influence tumor-associated stromal cells in a way that ultimately contributes to patient prognosis.

Low-Concentration Tributyltin Decreases GluR2 Expression via Nuclear Respiratory Factor-1 Inhibition.

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Ishida, Keishi; Aoki, Kaori; Takishita, Tomoko; Miyara, Masatsugu; Sakamoto, Shuichiro; Sanoh, Seigo; Kimura, Tomoki; Kanda, Yasunari; Ohta, Shigeru; Kotake, Yaichiro

2017-08-11

Tributyltin (TBT), which has been widely used as an antifouling agent in paints, is a common environmental pollutant. Although the toxicity of high-dose TBT has been extensively reported, the effects of low concentrations of TBT are relatively less well studied. We have previously reported that low-concentration TBT decreases α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA)-type glutamate receptor subunit 2 ( GluR2 ) expression in cortical neurons and enhances neuronal vulnerability to glutamate. However, the mechanism of this TBT-induced GluR2 decrease remains unknown. Therefore, we examined the effects of TBT on the activity of transcription factors that control GluR2 expression. Exposure of primary cortical neurons to 20 nM TBT for 3 h to 9 days resulted in a decrease in GluR2 mRNA expression. Moreover, TBT inhibited the DNA binding activity of nuclear respiratory factor-1 (NRF-1), a transcription factor that positively regulates the GluR2 . This result indicates that TBT inhibits the activity of NRF-1 and subsequently decreases GluR2 expression. In addition, 20 nM TBT decreased the expression of genes such as cytochrome c, cytochrome c oxidase (COX) 4, and COX 6c, which are downstream of NRF-1. Our results suggest that NRF-1 inhibition is an important molecular action of the neurotoxicity induced by low-concentration TBT.

Low-Concentration Tributyltin Decreases GluR2 Expression via Nuclear Respiratory Factor-1 Inhibition

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Ishida, Keishi; Aoki, Kaori; Takishita, Tomoko; Miyara, Masatsugu; Sakamoto, Shuichiro; Sanoh, Seigo; Kimura, Tomoki; Kanda, Yasunari; Ohta, Shigeru; Kotake, Yaichiro

2017-01-01

Tributyltin (TBT), which has been widely used as an antifouling agent in paints, is a common environmental pollutant. Although the toxicity of high-dose TBT has been extensively reported, the effects of low concentrations of TBT are relatively less well studied. We have previously reported that low-concentration TBT decreases α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA)-type glutamate receptor subunit 2 (GluR2) expression in cortical neurons and enhances neuronal vulnerability to glutamate. However, the mechanism of this TBT-induced GluR2 decrease remains unknown. Therefore, we examined the effects of TBT on the activity of transcription factors that control GluR2 expression. Exposure of primary cortical neurons to 20 nM TBT for 3 h to 9 days resulted in a decrease in GluR2 mRNA expression. Moreover, TBT inhibited the DNA binding activity of nuclear respiratory factor-1 (NRF-1), a transcription factor that positively regulates the GluR2. This result indicates that TBT inhibits the activity of NRF-1 and subsequently decreases GluR2 expression. In addition, 20 nM TBT decreased the expression of genes such as cytochrome c, cytochrome c oxidase (COX) 4, and COX 6c, which are downstream of NRF-1. Our results suggest that NRF-1 inhibition is an important molecular action of the neurotoxicity induced by low-concentration TBT. PMID:28800112

BDNF and COX-2 participate in anti-depressive mechanisms of catalpol in rats undergoing chronic unpredictable mild stress.

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Wang, Jun-Ming; Yang, Lian-He; Zhang, Yue-Yue; Niu, Chun-Ling; Cui, Ying; Feng, Wei-Sheng; Wang, Gui-Fang

2015-11-01

Catalpol, a major compound in Rehmannia glutinosa with both medicinal and nutritional values, has been previously confirmed to shorten the duration of immobility in mice exposed to tail suspension and forced swimming tests. This study attempted to examine the anti-depressive mechanisms of catalpol in rats undergoing chronic unpredictable mild stress (CUMS) by involving brain-derived neurotrophic factor (BDNF) and cyclooxygenase-2 (COX-2). CUMS-exposed rats were given catalpol daily (5, 10, and 20mg/kg, ig) or a reference drug, fluoxetine hydrochloride (FH, 10mg/kg, ig), at 5 weeks after starting the CUMS procedure. Sucrose preference test was performed to observe depression-like behavior, and serum and brain tissues were used for neurochemical and fluorescent quantitative reverse transcription PCR analysis. CUMS induced depression-like behavior, whereas catalpol and FH administration attenuated this symptom. Moreover, CUMS caused excessively elevated levels of serum corticosterone, an index of hypothalamic-pituitary-adrenal (HPA) axis hyperactivation, in a manner attenuated by catalpol and FH administration. Catalpol administration also further decreased BDNF activities, downregulated the mRNA expression of BDNF and tropomyosin-related kinase B (TrkB), and reversed the excessive elevation in the activities and mRNA expression levels of COX-2 and prostaglandin E2 (PGE2) in the hippocampus and frontal cortex of rats undergoing CUMS. Results indicate that catalpol can ameliorate CUMS-induced depression-like behavior, and suggest its mechanisms may partially be ascribed to restoring HPA axis dysfunctions, upregulating BDNF expression and its cognate receptor TrkB, and downregulating COX-2 expression, thereby reducing PGE2 levels in the brain. Copyright © 2015 Elsevier Inc. All rights reserved.

Effect of plant extracts on H2O2-induced inflammatory gene expression in macrophages

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Pomari, Elena; Stefanon, Bruno; Colitti, Monica

2014-01-01

Background Arctium lappa (AL), Camellia sinensis (CS), Echinacea angustifolia, Eleutherococcus senticosus, Panax ginseng (PG), and Vaccinium myrtillus (VM) are plants traditionally used in many herbal formulations for the treatment of various conditions. Although they are well known and already studied for their anti-inflammatory properties, their effects on H2O2-stimulated macrophages are a novel area of study. Materials and methods Cell viability was tested after treatment with increasing doses of H2O2 and/or plant extracts at different times of incubation to identify the optimal experimental conditions. The messenger (m)RNA expression of TNFα, COX2, IL1β, NFκB1, NFκB2, NOS2, NFE2L2, and PPARγ was analyzed in macrophages under H2O2 stimulation. The same genes were also quantified after plant extract treatment on cells pre-stimulated with H2O2. Results A noncytotoxic dose (200 μM) of H2O2 induced active mRNA expression of COX2, IL1β, NFE2L2, NFκB1, NFκB2, NOS2, and TNFα, while PPARγ was depressed. The expression of all genes tested was significantly (P<0.001) regulated by plant extracts after pre-stimulation with H2O2. COX2 was downregulated by AL, PG, and VM. All extracts depressed IL1β expression, but upregulated NFE2L2. NFκB1, NFκB2, and TNFα were downregulated by AL, CS, PG, and VM. NOS2 was inhibited by CS, PG, and VM. PPARγ was decreased only after treatment with E. angustifolia and E. senticosus. Conclusion The results of the present study indicate that the stimulation of H2O2 on RAW267.4 cells induced the transcription of proinflammatory mediators, showing that this could be an applicable system by which to activate macrophages. Plant extracts from AL, CS, PG, and VM possess in vitro anti-inflammatory activity on H2O2-stimulated macrophages by modulating key inflammation mediators. Further in vitro and in vivo investigation into molecular mechanisms modulated by herbal extracts should be undertaken to shed light on the development of novel

The role of Phosphatidylinositol 3 kinase (PI3K and Cycloxygenase-2 (COX2 in carcinogenesis of colorectal polyps

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Raul Alberto Anselmi Júnior

2018-01-01

Full Text Available Objectives: Determine immunohistochemical expression of Phosphatase and tensin homolog (PTEN, Phosphatidylinositol 3 kinase (PI3K, Cycloxygenase-2 (COX2 and one proliferation marker (Ki67 in colorectal polyps and correlate with clinical and pathological data in search of carcinogenic pathways. Methods: The reports of 297 polyps diagnosed through endoscopy were reviewed for parameters including age, gender, prior colorectal cancer, the presence of multiple polyps, and polyps’ location, appearance and size. Was conducted a microscopic morphometric computerized analysis of immunohistochemical expression using, the selected antibodies and correlated with clinical and pathological variables. Results: The tissue immunohistochemical expression was higher in right colon polyps for the proliferation marker and Phosphatidylinositol 3 kinase (p ≤ 0.0001 and 0.057 respectively. Cycloxygenase-2 and Phosphatase and tensin homolog demonstrated higher tissue immunoexpression in pedunculated polyps (p = 0.009 and 0.002 respectively. Cycloxygenase-2 exhibited higher immunoexpression in larger polyps (p = 0.005. Phosphatidylinositol 3 kinase, Cycloxygenase-2, Phosphatase and tensin homolog and the proliferation marker exhibited higher immunoexpression in high-grade dysplastic polyps (p = 0.031, 0.013, 0.044 and <0.001 respectively. Phosphatase and tensin homolog labeling was higher in polyps with high-grade dysplasia and lower in some of serrated lesions (p = 0.044. Conclusions: The greater expression of the proliferation marker and Phosphatidylinositol 3 kinase in the right colon may be related to right-sided colorectal carcinogenesis. The proliferation marker, Cycloxygenase-2 and Phosphatidylinositol 3 kinase results can be associated with progression of polyps to colorectal cancer. The higher Phosphatase and tensin homolog expression suggests its attempt to control the cell cycle. Resumo: Objetivos: Determinar a expressão imuno-histoquímica de

Hypomethylation of inflammatory genes (COX2, EGR1, and SOCS3) and increased urinary 8-nitroguanine in arsenic-exposed newborns and children

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Phookphan, Preeyaphan; Navasumrit, Panida [Laboratory of Environmental Toxicology, Chulabhorn Research Institute, Laksi, Bangkok (Thailand); Post-graduate Program in Environmental Toxicology, Chulabhorn Graduate Institute, Laksi, Bangkok (Thailand); Center of Excellence on Environmental Health, Toxicology (EHT), Office of the Higher Education Commission, Ministry of Education (Thailand); Waraprasit, Somchamai; Promvijit, Jeerawan; Chaisatra, Krittinee; Ngaotepprutaram, Thitirat [Laboratory of Environmental Toxicology, Chulabhorn Research Institute, Laksi, Bangkok (Thailand); Ruchirawat, Mathuros, E-mail: mathuros@cri.or.th [Laboratory of Environmental Toxicology, Chulabhorn Research Institute, Laksi, Bangkok (Thailand); Center of Excellence on Environmental Health, Toxicology (EHT), Office of the Higher Education Commission, Ministry of Education (Thailand)

2017-02-01

Early-life exposure to arsenic increases risk of developing a variety of non-malignant and malignant diseases. Arsenic-induced carcinogenesis may be mediated through epigenetic mechanisms and pathways leading to inflammation. Our previous study reported that prenatal arsenic exposure leads to increased mRNA expression of several genes related to inflammation, including COX2, EGR1, and SOCS3. This study aimed to investigate the effects of arsenic exposure on promoter DNA methylation and mRNA expression of these inflammatory genes (COX2, EGR1, and SOCS3), as well as the generation of 8-nitroguanine, which is a mutagenic DNA lesion involved in inflammation-related carcinogenesis. Prenatally arsenic-exposed newborns had promoter hypomethylation of COX2, EGR1, and SOCS3 in cord blood lymphocytes (p < 0.01). A follow-up study in these prenatally arsenic-exposed children showed a significant hypomethylation of these genes in salivary DNA (p < 0.01). In vitro experiments confirmed that arsenite treatment at short-term high doses (10–100 μM) and long-term low doses (0.5–1 μM) in human lymphoblasts (RPMI 1788) caused promoter hypomethylation of these genes, which was in concordance with an increase in their mRNA expression. Additionally, the level of urinary 8-nitroguanine was significantly higher (p < 0.01) in exposed newborns and children, by 1.4- and 1.8-fold, respectively. Arsenic accumulation in toenails was negatively correlated with hypomethylation of these genes and positively correlated with levels of 8-nitroguanine. These results indicated that early-life exposure to arsenic causes hypomethylation of COX2, EGR1, and SOCS3, increases mRNA expression of these genes, and increases 8-nitroguanine formation. These effects may be linked to mechanisms of arsenic-induced inflammation and cancer development later in life. - Highlight: • Early-life arsenic exposure caused promoter hypomethylation of COX2, EGR1 and SOCS3. • Hypomethylation of these genes is

Hypomethylation of inflammatory genes (COX2, EGR1, and SOCS3) and increased urinary 8-nitroguanine in arsenic-exposed newborns and children

International Nuclear Information System (INIS)

Phookphan, Preeyaphan; Navasumrit, Panida; Waraprasit, Somchamai; Promvijit, Jeerawan; Chaisatra, Krittinee; Ngaotepprutaram, Thitirat; Ruchirawat, Mathuros

2017-01-01

Early-life exposure to arsenic increases risk of developing a variety of non-malignant and malignant diseases. Arsenic-induced carcinogenesis may be mediated through epigenetic mechanisms and pathways leading to inflammation. Our previous study reported that prenatal arsenic exposure leads to increased mRNA expression of several genes related to inflammation, including COX2, EGR1, and SOCS3. This study aimed to investigate the effects of arsenic exposure on promoter DNA methylation and mRNA expression of these inflammatory genes (COX2, EGR1, and SOCS3), as well as the generation of 8-nitroguanine, which is a mutagenic DNA lesion involved in inflammation-related carcinogenesis. Prenatally arsenic-exposed newborns had promoter hypomethylation of COX2, EGR1, and SOCS3 in cord blood lymphocytes (p < 0.01). A follow-up study in these prenatally arsenic-exposed children showed a significant hypomethylation of these genes in salivary DNA (p < 0.01). In vitro experiments confirmed that arsenite treatment at short-term high doses (10–100 μM) and long-term low doses (0.5–1 μM) in human lymphoblasts (RPMI 1788) caused promoter hypomethylation of these genes, which was in concordance with an increase in their mRNA expression. Additionally, the level of urinary 8-nitroguanine was significantly higher (p < 0.01) in exposed newborns and children, by 1.4- and 1.8-fold, respectively. Arsenic accumulation in toenails was negatively correlated with hypomethylation of these genes and positively correlated with levels of 8-nitroguanine. These results indicated that early-life exposure to arsenic causes hypomethylation of COX2, EGR1, and SOCS3, increases mRNA expression of these genes, and increases 8-nitroguanine formation. These effects may be linked to mechanisms of arsenic-induced inflammation and cancer development later in life. - Highlight: • Early-life arsenic exposure caused promoter hypomethylation of COX2, EGR1 and SOCS3. • Hypomethylation of these genes is

Radiation Therapy Overcomes Adverse Prognostic Role of Cyclooxygenase-2 Expression on Reed-Sternberg Cells in Early Hodgkin Lymphoma

International Nuclear Information System (INIS)

Mestre, Francisco; Gutiérrez, Antonio; Rodriguez, Jose; Ramos, Rafael; Garcia, Juan Fernando; Martinez-Serra, Jordi; Casasus, Marta; Nicolau, Cristina; Bento, Leyre; Herraez, Ines; Lopez-Perezagua, Paloma; Daumal, Jaime; Besalduch, Joan

2015-01-01

Purpose: To analyze the role of radiation therapy (RT) on the adverse prognostic influence of cyclooxygenase-2 (COX-2) expression on Reed-Sternberg (RS) cells, in the setting of early Hodgkin lymphoma (HL) treated with ABVD (adriamycin, vinblastine, bleomycin, dacarbazine). Methods and Materials: In the present study we retrospectively investigated the prognostic value of COX-2 expression in a large (n=143), uniformly treated early HL population from the Spanish Network of HL using tissue microarrays. Univariate and multivariate analyses were done, including the most recognized clinical variables and the potential role of administration of adjuvant RT. Results: Median age was 31 years; the expression of COX-2 defined a subgroup with significantly worse prognosis. Considering COX-2 + patients, those who received RT had significantly better 5-year progression-free survival (PFS) (80% vs 54% if no RT; P=.008). In contrast, COX-2 − patients only had a modest, nonsignificant benefit from RT in terms of 5-year PFS (90% vs 79%; P=.13). When we compared the outcome of patients receiving RT considering the expression of COX-2 on RS cells, we found a nonsignificant 10% difference in terms of PFS between COX-2 + and COX-2 − patients (P=.09), whereas the difference between the 2 groups was important (25%) in patients not receiving RT (P=.04). Conclusions: Cyclooxygenase-2 RS cell expression is an adverse independent prognostic factor in early HL. Radiation therapy overcomes the worse prognosis associated with COX-2 expression on RS cells, acting in a chemotherapy-independent way. Cyclooxygenase-2 RS cell expression may be useful for determining patient candidates with early HL to receive consolidation with RT

Prevotella intermedia induces prostaglandin E2 via multiple signaling pathways.

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Guan, S-M; Fu, S-M; He, J-J; Zhang, M

2011-01-01

Prostaglandin E(2) (PGE(2)) plays important roles in the bone resorption of inflammatory diseases such as rheumatoid arthritis and periodontitis via specific prostaglandin receptors (i.e., EP1-EP4). In this study, the authors examined whether Prevotella intermedia regulates PGE(2) production and EP expression in human periodontal ligament fibroblasts (hPDLs); they also explored the potential signaling pathways involved in PGE(2) production. P. intermedia induced PGE(2) production and cyclooxygenase-2 (COX-2) expression in a dose- and time-dependent manner. Indomethacin and NS-398 completely abrogated the P. intermedia-induced PGE(2) production without modulating COX-2 expression. Specific inhibitors of extracellular signal-regulated kinase, c-Jun N-terminal kinase, p38, phosphatidylinositol 3-kinase, and protein kinase C--but not c-AMP and protein kinase A--significantly attenuated the P. intermedia-induced COX-2 and PGE(2) expression. P. intermedia reduced EP1 expression in a concentration- and time-dependent manner. The results indicate that the COX-2-dependent induction of PGE(2) by P. intermedia in hPDLs is mediated by multiple signaling pathways.

SOX2 expression is associated with a cancer stem cell state and down-regulation of CDX2 in colorectal cancer

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Lundberg, Ida V.; Edin, Sofia; Eklöf, Vincy; Öberg, Åke; Palmqvist, Richard; Wikberg, Maria L.

2016-01-01

To improve current treatment strategies for patients with aggressive colorectal cancer (CRC), the molecular understanding of subgroups of CRC with poor prognosis is of vast importance. SOX2 positive tumors have been associated with a poor patient outcome, but the functional role of SOX2 in CRC patient prognosis is still unclear. An in vitro cell culture model expressing SOX2 was used to investigate the functional role of SOX2 in CRC. In vitro findings were verified using RNA from fresh frozen tumor tissue or immunohistochemistry on formalin fixed paraffin embedded (FFPE) tumor tissue from a cohort of 445 CRC patients. Using our in vitro model, we found that SOX2 expressing cells displayed several characteristics of cancer stem cells; such as a decreased proliferative rate, a spheroid growth pattern, and increased expression of stem cell markers CD24 and CD44. Cells expressing SOX2 also showed down-regulated expression of the intestinal epithelial marker CDX2. We next evaluated CDX2 expression in our patient cohort. CDX2 down-regulation was more often found in right sided tumors of high grade and high stage. Furthermore, a decreased expression of CDX2 was closely linked to MSI, CIMP-high as well as BRAF mutated tumors. A decreased expression of CDX2 was also, in a stepwise manner, strongly correlated to a poor patient prognosis. When looking at SOX2 expression in relation to CDX2, we found that SOX2 expressing tumors more often displayed a down-regulated expression of CDX2. In addition, SOX2 expressing tumors with a down-regulated CDX2 expression had a worse patient prognosis compared to those with retained CDX2 expression. Our results indicate that SOX2 expression induces a cellular stem cell state in human CRC with a decreased expression of CDX2. Furthermore, a down-regulated expression of CDX2 results in a poor patient prognosis in CRC and at least part of the prognostic importance of SOX2 is mediated through CDX2 down-regulation. The online version of this

Synthesis and evaluation of a radioiodinated lumiracoxib derivative for the imaging of cyclooxygenase-2 expression

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Kuge, Yuji; Obokata, Naoyuki; Kimura, Hiroyuki; Katada, Yumiko; Temma, Takashi; Sugimoto, Yukihiko; Aita, Kazuki; Seki, Koh-ichi; Tamaki, Nagara; Saji, Hideo