• Asian Pacific Journal of Cancer Prevention
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• 제15권7호
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• pp.3041-3044
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• 2014

The aim of this work was to analyze methylation of the promoter sites of the ESR1 and PGR genes and to determine correlations with immunohistochemical expression of estrogen and progesterone receptors in ductal and lobular breast cancers. An observational, descriptive, molecular study was conducted on 20 ductal and 20 lobular breast cancer samples with immunohistochemical determination of estrogen and progesterone receptor expression. The methylation analysis of ESR1 and PGR promoter sites was carried-out by methylation-specific PCR. For correlation analysis, Kendall's tau coefficient was determined. Positive correlations were found between estrogen and progesterone receptors, estrogen receptor and unmethylated progesterone receptor, progesterone receptor, and unmethylated progesterone receptor. Negative correlations were found between estrogen receptor and methylated progesterone receptor, progesterone receptor and methylated progesterone receptor, methylated and unmethylated estrogen receptor, and methylated and unmethylated progesterone receptor. The results suggest that methylation of promoter sites of ESR1 and PGR is a relatively uncommon event in ductal and lobular breast cancer, and also suggest that the determination of epigenetic states of ESR1 and PGR could represent an alternative or complement to the histopathological expression analysis.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1997년도 춘계학술대회
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• pp.107-107
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• 1997

Cytochrome P450 enzymes have been intensively investigated in hepatic tissues and several mammalian cell lines. Compared to most studies about cytochrome P450 isozymes in liver in vivo and hepatic, cell lines in vitro, the study of cytochrome P450IA1 in human breast cancer cells could be very important to understand the mechanism of the regulation of CYPIA1 gene expression and cell growth. MCF-7 human breast cancer cells are well characterized to study estrogen and antiestrogen action due to the fact that they contain high level of estrogen receptor and have biological markers characterized. And also MCF-7 cells express high level of arylhydrocarbon hydroxylase activity and human cytochrome P450IA1 cDNA was cloned from MCF-7 cells. Ah receptor was characterized in many breast cancer cell lines and polycyclic aromatic hydrocarbon such as 3-MC induced the expression of CYPIA1 gene and cytochrome P450- dependent monooxygenase activity. We undertook a study to examine the effect of estrogens and other chemicals on the regulation of human CYPIA1 gene expression in MCF-7 cells via RTPCR analysis, that might help us to understand the mechanism of the regulation of CYPIA1 gene expression and MCF-7 cell growth. Expression vector containing the functional 5'-regulatory region of human CYPIA1 fused to the CAT reporter gene was transfected into estrogen receptor positive MCF-T cells or estrogen receptor negative MDA-MB-231 cells. After these cells were treated with various chemicals, RTPCR was carried out to measure both CYPIA1 mRNA and CAT mRNA levels. 1nM 3-MC increased in both P450 and CAT mRNA levels over those of control by two folds in MCF-7 cells but does not in MDA-MB-231 cells. Estrogen or tamoxifen or retinoic acid or chrysin decreased in both P450 and CAT mRNA levels that were induced by 3-MC in MCF-7 when each chemical was administered with 3-MC concomitantly. These results suggested that the level of CYPIA1 gene expression is modulated with estrogen-related molecules and make it possible to speculate that ER is related to CYPIA1 gene expression and cell growth in breast cancer cells. [Supported by grants from the Korean Ministry of Education ]

• Asian Pacific Journal of Cancer Prevention
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• 제16권12호
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• pp.4949-4954
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• 2015

The present study was planned to investigate the role of sex hormone receptor gene expression in the pathogenesis of hepatocellular carcinoma (HCC). Adult male Wistar rats were divided into seven groups. Group (1) was negative control. Groups (2), (5), (6), and (7) were orally administered with N-nitrosodiethylamine for the induction of HCC, then group (2) was left untreated, group (5) was orally treated with curcumin, group (6) was orally treated with carvacrol, and group (7) was intraperitoneally injected with doxorubicin, whereas groups (3) and (4) were orally administered only curcumin and carvacrol, respectively. The HCC group showed significant upregulation in the androgen receptor (AR) and the estrogen receptor-alpha ($ER{\alpha}$) gene expression levels in the liver tissue. On the contrary, HCC groups treated with either curcumin or carvacrol showed significant downregulation in AR and $ER{\alpha}$ gene expression levels in the liver tissue. In conclusion, the obtained data highlight that both AR and $ER{\alpha}$ but not estrogen receptor-beta ($ER{\beta}$) gene expression may contribute to the male prevalence of HCC induced in male rats. Interestingly, both curcumin and carvacrol were found to have a promising potency in alleviating the male predominating HCC.

• 한국발생생물학회지:발생과생식
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• 제11권1호
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• pp.43-47
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• 2007

Transforming growth $factor-{\beta}(TGF-{\beta})$ 신호의 매개자 역할을 하는 Smad 계열 단백질은 발생과정에 중요한 역할을 한다고 알려져 있다. Estrogen receptor(ER)와 구조적으로 유사한 estrogen receptor-related receptor(ERR)은 포유동물에서 후기 배발생기에 외배엽 형성과 관련이 되어 있는 고아핵수용체이다. 본 연구에서는 해양무척추동물의 초기발생과정과 계절번식기 동안에 Smad3와 ERR의 유전자 발현이 발생과정과 성숙에 어떠한 연관성을 갖고 있는지 알아보기 위하여, 동해안 연안에 주로 서식하는 극피동물문 둥근성게과 둥근성게(Strongylocentrotus nudus)를 재료로 하여 계절별 및 배발생 과정중에 Smad3와 $ERR{\beta}$ like 1의 mRNA 농도를 real-time PCR 방법으로 조사하였다. Smad3 mRNA는 샘플링을 시작한 2004년 2월의 생식소와 비교하면 4월부터 그 농도가 증가하기 시작하여 6월까지 증가하였으며, 산란기인 8월에 감소하였다가 10월부터 12월까지 높은 수준을 유지하였다. $ERR{\beta}$ like 1 mRNA는 6월까지 낮은 수준이었으나, 산란기인 8월에 급증한 후 다시 감소하였다. 수정란부터 초기 유생기까지 발생과정을 분석한 결과, Smad3 mRNA는 8세포기 및 16세포기에 높은 발현이 관측되었다. 한편, $ERR{\beta}$ like 1 mRNA는 포배기, 낭배기, 초기 유생기에 현저하게 높은 발현패턴을 보였다. 이상의 결과로부터 둥근성게의 산란기 및 발생배의 발생후기에 $ERR{\beta}$ like 1이 중요한 역할을 담당할 것으로 추정되며, 초기 난할시기에는 Smad3의 관련성이 시사되었다.

• 상하수도학회지
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• 제20권6호
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• pp.893-904
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• 2006

To improve sensitivity of biosensor as yeast two-hybrid detection system for estrogenic activity of suspected chemicals, we tested effects of several combinations of the bait and fish components in the two-hybrid system on Saccharomyces cerevisiae inducted a chromosome-integrated lacZ reporter gene that was under the control of CYC1 promoter and the upstream Gal4p-binding element $UAS_{GAL}$. The bait components that were fused with the Gal4p DNA binding domain are full-length human estrogen receptor ${\alpha}$ and its ligand-binding domain. The fish components that were fused with the Gal4p transcriptional activation domain were nuclear receptor-binding domains of co-activators SRC1 and TIF2. We found that the combination of the full-length human estrogen receptor ${\alpha}$ with the nuclear receptor-binding domain of co-activator SRC1 was most effective for the estrogen-dependent induction of reporter activity among the two-hybrid systems so far reported. The relative strength of transcriptional activation by representative natural and xenobiotic chemicals was well correlated with their estrogenic potency that had been reported with other assay systems.

• 생명과학회지
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• 제13권3호
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• pp.314-323
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• 2003

지금까지 estrogen 호르몬이 유방암의 발생과 진전에 관여한다는 사실을 뒷받침 할 수 있는 여러 가지 증거가 제시되어 왔지만, 암화에 관여하고 있는 estrogen의 분자생물학적 작용기전에 대해서는 아직 명확히 알려져 있지 않다. 유방암 세포의 발암현상은 다양한 핵 수용체들과 이들 각각의 신호전달경로들 사이의 기능적 상호교류 (Functional Cross-talk)에 의해 조절되는 것으로 추측되고 있다. 그러므로, 유방암세포의 성장과 증식에 관여하는 신호전달경로중에서 estrogen의 작용을 조절할 수 있는 핵 수용체를 밝혀내고, 이러한 수용체와 estrogen receptor사이에 어떠한 기능적 상호교류가 일어나는지를 규명하는 것은 암화와 관련된 estrogen의 분자생물학적 작용기전을 이해하는 데 중요한 진전을 가져올 수 있다. 따라서 본 연구의 목적은 유방암세포 내에서 estrogen의 작용이 xenobiotic nuclear receptor에 의해 조절되는지를 규명하기 위하여, 두 종류의 유방암세포인 estrogen receptor가 발현되는 MCF-7 세포와 ER의 발현이 일어나지 않는 MDA-MB-231세포를 배양하여, 에스트로겐에 의해 전사가 촉진되는 보고유전자의 발현이 CAR, SXR, 그리고 PPAR${\gamma}$에 의해서 어떻게 영향을 받는지를 조사하고 그 결과를 간암세포에서의 반응과 비교 분석하였다. 최근에 보고된 연구결과와 일치하게, xenobiotic nuclear receptor가 간세포에서 일어나는 에스트로겐 수용체의 신호전달경로에 영향을 줄 수 있음을 확인하였다. PPAR${\gamma}$를 제외한 핵 수용체 CAR와 SXR은 ER의 전사활성 효과를 현저하게 또는 어느 정도 각각 감소시켰다. Hep G2세포에서와는 달리 유방암세포에서는 조사된 세가지의 xenobiotic 핵 수용체가 ER의 전사활성에 그다지 영향을 미치지 않거나 유방암세포의 종류와 각각의 수용체에 따라서 다소 촉진하는 경향을 나타내었다. MCF-7 세포에서는 CAR와 PPAR${\gamma}$을 제외한 SXR이 ER의 transactivation 효과를 약간 촉진한 반면 MDA-MB-231세포는 SXR을 제외한 CAR와 PPAR${\gamma}$에 의해 ER의 transactivation 효과가 약간 증가되는 경향을 보였다. 이러한 결과는 유방암세포에서는 CAR, SXR, PPAR${\gamma}$과 같은 xenobiotic nuclear receptor에 의한 ER transactivation 효과가 간암세포와는 다르게 나타나며, 유방암의 종류에 따라서 endogenous CAR, SXR, PPAR${\gamma}$수용체가 다르게 발현됨으로써 이들에 대한 반응이 서로 상이한 특징을 나타낼 수 있을 것으로 사료된다. 따라서 estrogen receptor에 의해 매개되는 estrogn의 전사활성조절기전이 표적세포에 따라 다른 경로를 포함 할 수 있음을 시사한다.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2001년도 International Symposium on Dietary and Medicinal Antimutgens and Anticarcinogens
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• pp.186-186
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• 2001

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is an environmental toxin that activates the aryl hydrocarbon receptor (AhR) and disrupts multiple endocrine signaling pathways by enhancing ligand metabolism, altering hormone synthesis, down regulating receptor levels, and interfering with gene transcription. And TCDD-mediated gene transactivation via the AhR has been shown to be dependent upon estrogen receptor (ER) expression in human breast cancer cells.(omitted)

• Biomolecules & Therapeutics
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• 제20권2호
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• pp.183-188
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• 2012

In this study, we examined the estrogenic activity of bavachin, a component of Psoralea corylifolia that has been used as a traditional medicine in Asia. Bavachin was purified from ethanolic extract of Psoralea corylifolia and characterized its estrogenic activity by ligand binding, reporter gene activation, and endogenous estrogen receptor (ER) target gene regulation. Bavachin showed ER ligand binding activity in competitive displacement of [$^3H$] $E_2$ from recombinant ER. The estrogenic activity of bavachin was characterized in a transient transfection system using $ER{\alpha}$ or $ER{\beta}$ and estrogen-responsive luciferase plasmids in CV-1 cells with an $EC_{50}$ of 320 nM and 680 nM, respectively. Bavachin increased the mRNA levels of estrogen-responsive genes such as pS2 and PR, and decreased the protein level of $ER{\alpha}$ by proteasomal pathway. However, bavachin failed to activate the androgen receptor in CV-1 cells transiently transfected with the corresponding receptor and hormone responsive reporter plasmid. These data indicate that bavachin acts as a weak phytoestrogen by binding and activating the ER.

• Toxicological Research
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• 제20권3호
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• pp.205-211
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• 2004

Concern that some chemicals in our environment may affect human health by disrupt-ing normal endocrine function has prompted a research on interactions of environmental contaminants with steroid hormone receptor. Toxaphene and chlordane are among the 12 persistent organic pollutants identified by the United Nations Environment Programme as requiring urgent attention. We compared the estrogenic activity of two organochlorine pesticides, toxaphene and chlordane, at estrogen receptor a (ER$\alpha$) and estrogen receptor $\beta$ (ER$\beta$). Human hepatoma cells (HepG2) were transiently transfected with rat ER$\alpha$ or ER$\beta$ plus an estrogen-responsive complement C3-luciferase (C3-Luc) reporter gene. After transfection, cells were treated with various concentrations of toxaphene and chlordane to investigate agonism or antagonism of these chemicals. Both toxaphene and chlordane were potent agonists in HepG2 cells for ER$\alpha$. In contrast, these chemicals had a minimal agonist activity with ER$\beta$ and almost abolished 17$\beta$-estradiol-induced ER$\beta$-mediated activity. Therefore, toxaphene and chlordane behaved as an ER$\alpha$ agonist and an ER$\beta$ antagonist with estrogen-responsive reporter plasmid C3-Luc, and exposure to these organochlorine pesticides could have a crictical effect on normal endocrine function.

• 운동과학
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• 제21권2호
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• pp.243-254
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• 2012

본 연구는 폐경에 따른 에스트로겐 대사의 부정적인 영향의 방지 및 처치를 위한 효율적인 대체요법으로서 운동과 콩 단백질 추출물 섭취 프로그램의 활용가능성을 제시하고자 한다. 이에 난소 절제하여 폐경과 동일한 상태를 유도한 흰쥐를 대상으로 8주 동안 트레드밀을 이용한 지구성 운동과 콩 단백질 추출물 섭취의 복합적인 처치가 신체구성 및 골밀도, 혈중 에스트라디올농도, 간 조직에서의 에스트로겐 수용체의 유전자 발현양상, 혈중 글루코스, 중성지방, 인슐린 및 CRP 농도 등의 변화에 미치는 영향을 분석하였다. 난소절제그룹은 체중 및 체지방률이 증가하고, 혈중 에스트라디올농도 및 간 조직에서의 에스트로겐 수용체의 유전자 발현이 감소하였으며, 혈중 중성지방농도는 증가하였다. 8주간의 운동 및 콩 단백질 섭취에 의한 처치 후 에스트라디올농도, 에스트로겐 수용체 및 혈중 변인 등에 긍정적인 효과를 나타냈으나 골밀도에는 영향을 미치지 못한 것으로 나타났다. 따라서 난소절제 흰쥐의 8주간 운동 및 콩 단백질 추출물 처치가 에스트로겐 및 지방대사에 긍정적인 영향을 미칠 수 있는 가능성은 확인 되었으나, 운동강도 및 시간, 콩 단백질의 섭취량을 포함한 처치기간 등에 대한 계속적인 검토가 요구된다고 생각된다.