• Genomics & Informatics
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• 제12권4호
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• pp.247-253
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• 2014

Osteosarcoma is the most common primary bone tumor, generally affecting young people. While the etiology of osteosarcoma has been largely unknown, recent studies have suggested that cyclooxygenase-2 (COX-2) plays a critical role in the proliferation, migration, and invasion of osteosarcoma cells. To understand the mechanism of action of COX-2 in the pathogenesis of osteosarcoma, we compared gene expression patterns between three stable COX-2-overexpressing cell lines and three control cell lines derived from U2OS human osteosarcoma cells. The data showed that 56 genes were upregulated, whereas 20 genes were downregulated, in COX-2-overexpressed cell lines, with an average fold-change > 1.5. Among the upregulated genes, COL1A1, COL5A2, FBN1, HOXD10, RUNX2, and TRAPPC2 are involved in bone and skeletal system development, while DDR2, RAC2, RUNX2, and TSPAN31 are involved in the positive regulation of cell proliferation. Among the downregulated genes, HIST1H1D, HIST1H2AI, HIST1H3H, and HIST1H4C are involved in nucleosome assembly and DNA packaging. These results may provide useful information to elucidate the molecular mechanism of the COX-2-mediated malignant phenotype in osteosarcoma.

• 약학회지
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• 제42권2호
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• pp.214-219
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• 1998

Tissue distributions and association of cyclooxygenase-2 (COX-2) with inflammatory have led us to search for COX-2 selective inhibitors from natural products. Conceptually, COX- 2 selective inhibitors should be expected to retain anti-inflammatory efficacy by inhibition of PGs production while reducing or eliminating the gastric, renal and hemostatic side effects commonly associated with NSAIDs use. Thus, a logical approach to the treatment of inflammatory diseases should involve the inhibitors of COX-2. To develop new COX-2 inhibitors from natural products, two hundred crude drugs were screened by inhibiting PGD2 generation in bone marrow derived mast cells (BMMC). Among them, 6 methanol extracts of crude drugs such as, Bletillae rhizoma, Aconiti kgreani rhizoma, Belamcandae rhizoma, Nelumbinis semen, Gleniae radix, Aurantii immatri pericarpium inhibited more than 85% of BMMC COX-2 activity at a concentration 2.5${\mu}$g/ml.

• The Korean Journal of Physiology and Pharmacology
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• 제5권3호
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• pp.253-258
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• 2001

The present study was aimed to examine whether the expression of renin is associated with that of cyclooxygenase-2 (COX-2) in the kidney. Male Sprague-Dawley rats were made two-kidney, one clip (2K1C) or deoxycorticosterone acetate (DOCA)-salt hypertensive, to stimulate or to inhibit the endogenous renin-angiotensin system, respectively. The expression of renin and COX-2 mRNA was determined in the cortex of the kidney by reverse transcription-polymerase chain reaction. 2K1C hypertensive rats showed an increased expression of renin as well as of COX-2 in the clipped kidney. The expression of renin was decreased in parallel with that of COX-2 in the contralateral non-clipped kidney. Removal of the renal arterial clip reversed the expression of both genes, along with the blood pressure, to the control level. On the other hand, DOCA-salt hypertension was associated with parallel decreases of renin and COX-2 expression. These results indicate that renin and COX-2 genes are coordinately expressed in the kidney.

• International Journal of Oral Biology
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• 제31권1호
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• pp.21-26
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• 2006

Periodontopathogens including Porphyromonas gingivalis interact with host periodontal cells and the excessive subsequent host responses contribute a major part to the development of periodontal diseases. Cyclooxygenase(COX)-2-synthesized $PGE_2$ has detrimental activities in terms of periodontal pathogenesis. The present study investigated induction of COX-2 expression by P. gingivalis in human monocytic THP-1 cells. Live P. gingivalis increased expression of COX-2, but not that of COX-1, which was demonstrated at both mRNA and protein levels. Elevated levels of $PGE_2$ were released from P. gingivalis-infected THP-1 cells. Pharma-cological inhibition of p38 mitogen-activated protein kinase(MAPK) and extracellular signal-regulated kinase(ERK) substantially attenuated P. gingivalis-induced COX-2 mRNA expression. Indeed, activation of p38 MAPK and ERK was observed in P. gingivalis-infected THP-1 cells. Also, P. gingivalis induced activation of nuclear $factor-{\kappa}B\;(NF-{\kappa}B)$ which is an important transcription factor for COX-2. These results suggest that COX-2 expression is up regulated in P. gingivalis-infected monocytic cells, at least in part, via p38 MAPK, ERK, and $NF-{\kappa}B$.

• Asian Pacific Journal of Cancer Prevention
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• 제15권16호
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• pp.6787-6790
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• 2014

Background: The aim of this study was to evaluate cyclooxygenase-2 (COX-2) immunoreactivity in colorectal adenocarcinomas and to find correlations with different pathological features. Materials and Methods: This study included 35 cases of colorectal carcinoma foir which surgical colectomy specimens were collected. Immunohistochemical staining of COX-2 (cyclooxygenase-2) is done by using the Streptavidin-biotin technique. Results: This work reveals that COX-2 is positive in most cases of colorectal carcinoma and negative in normal colon tissue with statistically non significant relations between COX-2 immunostaining and different pathological features. Conclusions: Our data suggest over expression of COX-2 protein in colorectal carcinoma in contrast to normal mucosa, with a possible role in cell proliferation in carcinogenesis.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2003년도 Annual Meeting of KSAP : International Symposium on Pharmaceutical and Biomedical Sciences on Obesity
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• pp.96-96
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• 2003

Previously, wogonin (5,7-dihydroxy-8-methoxyflavone) was found to suppress proinflammatory enzyme expression including cyclooxygenase-2 (COX-2), contributing to in vivo anti-inflammatory activity against skin inflammation. However, the detailed effect on each skin cell type has not been understood. Therefore, present investigation was carried out to find the effect of wogonin on inflammation-associated gene expression from skin fibroblasts in culture using reverse transcriptase-polymerase chain reaction. As a result, it was found that wogonin (10 - 100 ${\mu}$M) clearly down-regulated COX -2 expression from NIH/3T3 cells treated with 12-O-tetradecanoylphorbol 13-acetate, interleukin-1${\beta}$ or tumor necrosis factor-a. But, the expression levels of COX-1, interleukin-1${\beta}$ and fibronectin were not significantly affected. This finding was well correlated with significant reduction of prostaglandin E$_2$(PGE$_2$) production by wogonin. As a comparison, NS-398 (selective cyclooxygenase-2 inhibitor) did not suppress COX -2 expression and other gene levels, while PGE$_2$production was potently reduced at 0.1 - 10 ${\mu}$M. All these results suggest that COX -2 down-regulation of skin fibroblasts may be, at least in part, one of anti-inflammatory mechanisms of wogonin against skin inflammation.

• Journal of Applied Biological Chemistry
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• 제64권4호
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• pp.375-382
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• 2021

조록나무는 제주도 및 일본 혼슈 이남, 중국 동남부, 타이완 등에 분포하는 조록나무과의 상록 교목으로, 항산화 및 tyrosinase, elastase의 억제에 효과적인 것으로 알려져 있지만 NO에 대한 억제 효능은 미미한 것으로 보고되었다. 이에 본 연구는 조록나무 잎 추출물(DL)에 biorenovation 생물 전환 기법을 적용하여 항 염증 활성을 증진 시키고자 수행되었다. 이들의 활성은 LPS로 자극된 RAW264.7 염증 모델에서 평가 되었으며 NO, inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) 및 전 염증성 사이토카인에 대한 억제 실험이 수행되었다. 그 결과, biorenovation을 적용한 조록나무 잎 추출물(DLB)는 독성이 없는 농도에서 DL대비 향상된 NO와 prostaglandin E2 억제효능을 나타내었으며, 이들의 합성 효소인 iNOS 및 COX-2의 발현에도 유의한 억제 경향을 나타내었다. 또한 대표적인 전 염증성 사이토 카인인 tumor necrosis factor-α, Interleukin 6, Interleukin-1β 에서도 향상된 억제 효능을 확인 하였다. 이러한 결과를 근거로 우리는 biorenovation을 통해 DL의 항염증 효능이 개선될 수 있으며, DLB가 효과적인 천연 항염증 소재로 적용될 수 있음을 제시한다.

• BMB Reports
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• 제42권9호
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• pp.552-560
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• 2009

Cyclooxygenases (COX-1 and COX-2) are ER-resident proteins that catalyze the committed step in prostanoid synthesis. COX-1 is constitutively expressed in many mammalian cells, whereas COX-2 is usually expressed inducibly and transiently. Abnormal expression of COX-2 has been implicated in the pathogenesis of chronic inflammation and various cancers; therefore, it is subject to tight and complex regulation. Differences in regulation of the COX enzymes at the posttranscriptional and posttranslational levels also contribute significantly to their distinct patterns of expression. Rapid degradation of COX-2 mRNA has been attributed to AU-rich elements (AREs) at its 3’UTR. Recently, microRNAs that can selectively repress COX-2 protein synthesis have been identified. The mature forms of these COX proteins are very similar in structure except that COX-2 has a unique 19-amino acid (19-aa) segment located near the C-terminus. This C-terminal 19-aa cassette plays an important role in mediation of the entry of COX-2 into the ER-associated degradation (ERAD) system, which transports ER proteins to the cytoplasm for degradation by the 26S proteasome. A second pathway for COX-2 protein degradation is initiated after the enzyme undergoes suicide inactivation following cyclooxygenase catalysis. Here, we discuss these molecular determinants of COX-2 expression in detail.

• Molecules and Cells
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• 제19권2호
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• pp.232-238
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• 2005

Corneal endothelial cells play an important role in maintaining the transparency and ionic balance of the cornea. Inflammation causes many changes in the intracellular and extracellular environment of the cornea, including acidosis. We examined the relationship between changes in extracellular pH and expression of cyclooxygenase-2 in cultured bovine corneal endothelial cells. When extracellular pH ($[pH]_o$) was reduced to pH 6.4, COX-2 mRNA increased, with a peak at 2 h. This was blocked by pretreatment with actinomycin D and incubation with spermine NONOate (SPER/NO, a nitric oxide donor). Exposure to the $H^+$ ionophore, carbonyl cyanide m-chlorophenylhydrazone (CCCP), also raised COX-2 mRNA levels. CCCP-induced COX-2 mRNA expression was also reduced by SPER/NO. These results were confirmed immuno-cytochemically. These data demonstrate that COX-2 expression is stimulated by the lowering of extracellular pH that could result from bacterial infection, and that this is countered by over-production of nitric oxide, which could also result from bacterial infection.

• 한국환경성돌연변이발암원학회지
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• 제25권4호
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• pp.143-149
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• 2005

The identification of COX-2 (cyclooxygenase-2) has led to potential novel insights on disease pathogenesis (atherosclerosis, cancer, Alzheimer's disease) and the regulation of normal organ function. The present in vivo study with estrogen or soy-isoflavones has provided evidence for the association between COX-2 and ICAM-1 (Intercellular adhersion molecule-1). In the system of mature female rats, soy-isoflavones exerted more pronounced effect on ICAM-1 inhibitory and COX-2 stimulatory effect than estrogen. In the system of ovariectomized estrogen deficient rats, the down-regulatory properties of soy-isoflavones on ICAM-1 was less evident, whereas estrogen exerted the inhibitory activity. These results demonstrate that COX-2 limits adhersion molecule expression on rat aorta cells and suggest that COX-2 may play a protective role in cardiovascular system in mature female rats. Soy-isoflavones appear to have beneficial effect on vascular systems through modulation of ICAM-1 and COX-2, and these molecules appeared to be closely associated.