• 한국독성학회:학술대회논문집
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• 한국독성학회 2002년도 Current Trends in Toxicological Sciences
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• pp.88-88
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• 2002

Cyclooxygenase(COX) metabolizes arachidonic acid to prostaglandins and thromboxanes. It has been reported that there is 'cross-talk' between COX-2 and nitric oxide synthase(NOS). Stimulation of eNOS of estrogen fed animal heart was not accompanied by the increase in COX-2 expression.(omitted)

• BMB Reports
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• 제48권2호
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• pp.109-114
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• 2015

The COX-2/$PGE_2$ pathway has been implicated in the occurrence and progression of cancer. The underlying mechanisms facilitating the production of COX-2 and its mediator, $PGE_2$, in cancer survival remain unknown. Herein, we investigated $PGE_2$-induced COX-2 expression and signaling in HL-60 cells following menadione treatment. Treatment with $PGE_2$ activated anti-apoptotic proteins such as Bcl-2 and Bcl-xL while reducing pro-apoptotic proteins, thereby enhancing cell survival. $PGE_2$ 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 $PGE_2$, and restored the menadione- induced cell death. In addition, pretreatment of cells with the MEK inhibitor PD98059 and the PKA inhibitor H89 abrogated the $PGE_2$-induced expression of COX-2, suggesting involvement of the MAPK and PKA pathways. These results demonstrate that $PGE_2$ signaling acts in an autocrine manner, and specific inhibition of $PGE_2$ will provide a novel approach for the treatment of leukemia.

• 대한골관절종양학회지
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• 제13권2호
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• pp.105-112
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• 2007

목적: 최근 골 및 연부조직 종양을 포함한 각종 악성 종양에서 cyclooxygenase-2 (COX-2) 의 발현 증가가 보고되고 있다. 그러나 연골 종양에서의 COX-2 발현에 대해서는 별로 알려진 바가 없다. 대상 및 방법: 내연골종 10예, 연골모세포종 11예, 연골점액양섬유종 5예, 통상적 연골육종 17예, 투명세포 연골육종 7예, 간엽성 연골육종 6예를 대상으로 COX-2에 대한 면역조직화학법을 시행하였다. 결과: 양성 연골 종양 중 연골모세포종 11예 중 6예(54.5%)에서 특징적인 강한 양성 반응을 나타내었다. 내연골종과 연골점액양섬유종은 단 1예를 제외하고는 모든 증례에서 음성이었다. 통상적인 연골육종에서 3예(17.6%)는 COX-2에 대해 강한 양성 반응을 보였는데 이러한 양성 증례는 모두 조직학적 등급 3의 분화가 나쁜 연골육종이었다. 투명세포 연골육종 중 2예(28.5%)는 국소적인 양성 반응을 나타내었고 모든 간엽성 연골육종은 음성이었다. 결론: 이러한 결과는 통상적인 연골육종에서 COX-2 과발현이 조직학적 등급 진행과 관계된 소견임을 시사한다. 연골모세포종의 COX-2 발현은 특별히 이 종양에 동반되는 종양 주변부의 염증성 변화를 유발하는 중요한 요소로 생각된다.

• Tuberculosis and Respiratory Diseases
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• 제63권1호
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• pp.31-41
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• 2007

연구배경: 폐암의 병인에 기여하거나 예후를 결정하는 인자에 대해서는 매우 다양한 인자와 다양한 상호 관계로 인하여 특히 유전자의 역할에 대해서는 결정적으로 알려진 것이 없어 앞으로 더 많은 연구가 필요한 실정이다. 이에 따라 본 연구에서는 COX-2, MMP-9, p53가 비소세포폐암에서 어떻게 발현되는지 세포면역학적으로 알아보고 임상 특성과 예후와 상관관계를 알아보고자 하였다. 대상 및 방법: 91명의 비소세포폐암을 대상으로 하여 후향적으로 임상특성을 고찰하고 COX-2, MMP-9, p53의 유전자 표현을 세포면역학적 방법을 통하여 검사하였다. 임상특성과 유전자 표현 패턴의 상관관계와 생존에 대한 예후인자로서의 역할에 대하여 조사하였다. 결 과: 1) 편평상피세포암에서는 흡연자과 남자가 우세한 비율을 차지하였으며 남자에서 흡연의 비율이 유의하게 높았다. 2) 전체 대상 환자에서 생존에 영향을 미치는 결정적인 인자는 근치적 절제술의 시행여부와 병기로 나타났다. 3) COX-2의 발현은 편평상피세포암 보다 선암에서 더 유의하게 높게 발현되었다. 4) COX-2, MMP-9, p53의 발현이 모두 되지 않는 비율은 선암에 비해 편평상피세포암에서 더 흔하게 관찰되었다. 5) p53돌연변이가 있으면서 COX-2와 MMP-9은 발현이 되지 않는 비소세포폐암환자의 생존기간이 다른 발현 양상을 보이는 경우에서의 생존기간보다 더 연장되어 보였다(생존기간의 중앙값; 165.6주). 6) COX-2의 발현과 MMP-9의 발현 사이에는 유의한 상관관계가 있었다. 7) 폐암을 근치적으로 절제한 환자의 경우에 COX-2의 발현은 유의한 예후인자였다. MMP-9는 근치적 절제술을 받지 못한 환자군에서 유의한 예후인자로 작용하였다.

• Toxicological Research
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• 제17권
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• pp.89-96
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• 2001

Recently, considerable attention has been focused on the role of cyclooxygenase-2 (COX-2) in the carcinogenesis as well as in inflammation. Improperly overexpressed COX-2 has been observed in many types of human cancers and transformed cells in culture. Thus, it is conceivable that targeted inhibition of abnormally or improperly up-regulated COX-2 provides one of the most effective and promising strategies for cancer prevention. A ubiquitous eukaryotic transcription factor, NF-kB is considered to be involved in regulation of COX-2 expression. Furthermore, extracellular-regulated protein kinase and p38 mitogen-activated protein (MAP) kinase appear to be key elements of the intracellular signaling cascades involved in NF-kB activation in response to a wide array of external stimuli. Certain chemopreventive phytochemicals suppress activation of NF-kB by blocking one or more of the MAP kinases, which may contribute to their inhibitory effects on COX-2 induction. One of the plausible mechanisms by which chemopreventive phytochemicals inhibit NF-kB activation involves suppression of degradation of the inhibitory unit I kB, which hampers subsequent translocation of p65, the functionally active subunit of NF-kB.

• IMMUNE NETWORK
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• 제6권3호
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• pp.123-127
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• 2006

Background: Caveolin-1 is a principal component of caveolae membranes in vivo. Although expression of caveolae structure and expression of caveolin family, caveolin-1, -2 and -3, was known in chondrocytes, the functional role of caveolae and caveolins in chondrocytes remains unknown. In this study, we investigated the role of caveolin-1 in articular chondrocytes. Methods: Rabbit articular chondrocytes were prepared from cartilage slices of 2-week-old New Zealand white rabbits by enzymatic digestion. Caveolin-1 cDNA was transfected to articular chondrocytes using LipofectaminePLUS. The cyclooxygenase-2 (COX-2) expression levels were determined by immunoblot analysis, immunostaining, immunohistochemistry, and prostaglandin $E_2\;(PGE_2)$ assay was used to measure the COX-2 activity. Results: Ectopic expression of caveolin-1 induced COX-2 expression and activity, as indicated by immunoblot analysis and $PGE_2$ assay. And also, overexpression of caveolin-1 stimulated activation of p38 kinase and ERK-1/-2. Inhibition of p38 kinase and ERK-1/-2 with SB203580 and PD98059, respectively, led to a dose-dependent decrease COX-2 expression and $PGE_2$ production in caveolin-1-transfected cells. Conclusion: Taken together, our data suggest that ectopic expression of caveolin-1 contributes to the expression and activity of COX-2 in articular chondrocytes through MAP kinase pathway.

• 대한화장품학회지
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• 제20권1호
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• pp.25-36
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• 1994

Gram 음성균의 세포벽 성분인 lipopolysaccharide는 각종 세포에서의 prostaglandin 합성을 증진 시키며 이는 cyclooxygenase-2의 선택적 발현에 기인한다는 사실이 이미 보고된 바 있다. 본 연구에서는 mouse peritoneal marophage를 대상으로 하여 LPS의 prostaglandin 합성 증진 작용에 대한 특성으로 검토함으로써, COX-2에 대한 선택적 저해제 검색에 이용될 수 있는지 그 가능성을 확인코자 하였다. LPS는 peritoneal macrophage에 처리시 약 8시간 정도의 lag time을 보인 후 prostaglandin 합성을 현저히 증진 시켰으며, 이는 주로 COX 활성의 증가에 기인하는 것으로 추정되었다. 또한 LPS의 작용은 항염증제인 dexamethasone에 의해서 강하게 억제 되었으며 metabolic labeling 결과 이는 COX-2의 생합성을 억제하는데 기인하는 것으로 확인되었다. 따라서 mouse peritoneal macrophage에서의 LPS에 의한 prostaglandin 합성 증진 작용은 rat alveolar macrophage와 정성적으로 동일함을 확인할 수 있었으며, 본 실험 조건은 COX-2에 대한 선택적 저해제 검색에 응용될 수 있음을 확인 하였다. 본 실험 조건하에서 비스테로이드성 항염제인 ketoprofen의 작용을 검토한 결과 ketoprofen은 COX-1에 비교적 선택적인 저해 작용을 보이는 것으로 추정 되었다.

• 대한물리치료과학회지
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• 제9권1호
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• pp.89-94
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• 2002

Prostaglandins are generated through two isoforms of the enzyme cyclooxygenase, constitutively expressed cyclooxygenase(COX)-1 and COX-2, which is induced at sites of inflammation. Inhibition of COX-2 is desirable as this may avoid side effects seen with NSAIDs. We examined the effects of transcutaneous electrical nerve stimulation and cold therapy on the levels of muscle cycloooxygenase-2 mRNA in rats of carrageenan-induced inflammatory. The method of behavioral assessment were paw withdrawal latency(PWL) and tail flick test(TFT). The COX-2 mRNA levels were quantified by reverse transcription-polymerase chain reaction (RT-PCR). Following the transcutaneous electrical nerve stimulation and cold therapy, PWL and TFT were increased and COX-2 mRNA expression in gastrocnemius muscles were decreased. These results suggest that a transcutaneous electrical nerve stimulation and cold therapy were good therapy for a muscle pain.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2001년도 International Symposium on Dietary and Medicinal Antimutgens and Anticarcinogens
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• pp.137-138
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• 2001

There has been accumulating evidence for the association of inflammatory tissue damage with the process of cancer development. Cyclooxygenase (COX), an important enzyme involved in mediating the inflammation, catalyzes the formation of prostaglandins (PGs) from arachidonic acid. There are two isoforms of COX, designated as COX-l and COX-2. COX-l is a housekeeping enzyme which is constitutively expressed and is thought to be involved in maintaining physiological functions.(omitted)

• Asian Pacific Journal of Cancer Prevention
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• 제15권12호
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• pp.4989-4994
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• 2014

Background: It has been reported that COX-2 expression is associated with MMP-2 expression in thyroid and breast cancers, suggesting that MMPs are linked to COX-2-mediated carcinogenesis. Several polymorphisms within the MMP2 promoter region have been reported in cases with oncogenesis and tumor progression, especially in colorectal carcinogenesis. Materials and Methods: This research evaluated risk of association of the SNPs, including genes for COX-2 (AIG transition at +202) and MMP-2 (Crr transition at-1306), with colorectal cancer in 125 patients and 125 healthy controls. Results and Conclusions: Our data confirmed that MMP2 C-1306 T mutations were significantly more common in colon cancer patients than in our control Saudi population; p=O.0121. On the other hand in our study, there was no significant association between genotype distribution ofthe COX2 polymorphism and colorectal cancer; p=0.847. An elevated frequency ofthe mutated genotype in the control group as compared to the patients subjects indeed suggested that this polymorphism could decrease risk in the Saudi population. Our study confirmed that the polymorphisms that could affect the expressions of MMP-2 and COX-2 the colon cancer patients were significantly higher than that in the COX-2 negative group. The frequency of individuals with MMP2 polymorphisms in colon cancer patients was higher than individuals with combination of COX2 and MMP2 polymorphisms. Our study confirmed that individuals who carried the polymorphisms that could affect the expressions ofCOX2 are more susceptible to colon cancer. MMP2 regulatory polymorphisms could be considered as protective; further studies need to confirm the results with more samples and healthy subjects.