• 한국동물학회:학술대회논문집
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• 한국동물학회 2003년도 한국생물과학협회 학술발표대회
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• pp.166.2-166
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• 2003

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• The Korean Journal of Physiology and Pharmacology
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• 제10권4호
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• pp.199-205
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• 2006

The functional expression of potassium $(K^+)$ channels has electrophysiologically been studied in bone cells from several species, however, their identity and regulation of gene expressions in bone cells are not well known. In the present study, to investigate how $K^+$ channel expressions are regulated by estrogen, we measured changes of transcript levels of various $Ca^{2+}$-activated ($K_{Ca}$) and ATP-sensitive $K^+$ channels in rat osteoblastic ROS 17/2.8 cells after treatment with estrogen. Application of 17${\beta}$-estradiol $(E_2)$ for 24 h and 48 h increased mRNA and protein expressions of inwardly rectifying $K^+$ channel (Kir) 6.2 and type 2 small conductance $K_{Ca}$ channel (SK2), respectively. Combined treatment of cells with 17${\beta}-E_2$ and ICI 182,780, a pure antiestrogen, suppressed 17${\beta}-E_2$-induced alterations of SK2 and Kir6.2 mRNA levels. In addition, treatment of cells with U0126, a specific inhibitor of extracellular receptor kinases (ERK)1/2, and SP600125, a specific inhibitor of c-jun N-terminal kinase (JNK) blocked the enhancing effects of 17${\beta}-E_2$ on SK2 and Kir6.2 protein expressions. On the other hand, blocking of p38 mitogen-activated protein kinase had no effect. Taken together, these results indicate that 17${\beta}-E_2$ modulates SK2 and Kir6.2 expressions through the estrogen receptor, involving ERK1/2 and JNK activations.

• 생명과학회지
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• 제13권4호
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• pp.529-534
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• 2003

홍화씨가 골절, 골다공증 및 골형성부전증 등의 골 질환 치료에 효과가 있다는 것이 알려져 민간요법으로 사용되고 있으나 홍화씨의 어떤 성분이 이러한 작용을 하는지에 관해서는 거의 밝혀져 있지 않다. 본 연구에서는 흥화씨의 sterol 조성을 분석하고 폐경기 여성들의 골다공증 치료에 사용되고 있는 합성 estrogen 대체물질로써 그 기능이 확인된 phytoestrogen 활성을 측정하였다. Cholesterol에서 성호르몬인 estrogen이 합성되는 것처럼 식물 sterol 도 phytoestrogen 합성을 위한 전구체 작용을 하는 것으로 알려져 있다. 홍화씨에 존재하는 식물성 sterol은 stigmast-5-en-3-ol (3$\beta$, 24S)-form인 ${\gamma}$-sitosterol (clionasterol)로 확인되었으며 홍화에 존재하는 식물성 sterol의 함량은 총지질의 약 4%를 함유하였다. 홍화씨의 sterol 분석은 GC-MS와 Wiley MS spectrum library를 사용하여 분석하였으며 홍화씨에 존재하는 중요한 4-desmethyl sterols 에는 sitosterol 만이 확인되었다. 홍화씨의 식물성 estrogen 효과는 $\beta$-estradiol ($10^{-8}$ M)의 활성을 1로 했을 때 홍화씨의 에탄을 층(5 mg/ml) 및 메탄올 층(5 mg/ml)에서 각각 0.37과 0.43으로 estrogen 유사효과를 나타내었다(ANOVA p<0.001). 홍화씨에 포함된 estrogen에 의한 전사활성 촉진은 MCF7/pDS-CAT-ERE119-Ad2MLP system을 사용하여 estrogen수용체와 reporter gene 발현을 이용하는 방법으로 세포에 직접 처리함으로써 phytoestrogen 활성을 측정할 수 있었다.

• 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.

• 약학회지
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• 제45권6호
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• pp.694-700
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• 2001

Synthetic pyrethroids are analysis of a natural chemical moiety, pyrethrin derived from the pyrethrum plant Chrysanthemum. The natural pyrethrin structure has been modified to be highly lipophilic and photostable, creating an effective pesticide and resulting in an increased presence in the environment. Worldwide, they are commonly used insecticides against ticks, mites, mosquitoes, and as treatment for human head lice and scabies. Therefore, human exposure to their compounds in extensive. Several studies on the effects of pyrethroids on thyroid hormone regulation, estrogen and androgen function have been reported and yet little has been done try assess their potential hormonal activities. Among humans, a pyrethroid compound was suggested to be the causal agent for gynecomastia in a group of Haitian men. The reports suggest that some pyrethroid compounds are capable of disrupting endocrine function. Therefore, we examined estrogenic/antiestrogenic potential of three pyrethroid insecticides, that is permethrin, allethrin and fenvalerate in human breast cancer cell and action mechanism mediated by the estrogen receptor. Fenvalerate showed weak estrogenic activity but aallethrin and permethrin showed no effect. In combination with high levels (10$^{-10}$ M, 10$^{-11}$ M) of 17$\beta$-estradiol and three synthetic pyrethroids inhibited cert proliferations in MCF7-BUS cell by 17$\beta$-estradiol. Whereas, fenvalerate increased cell proliferative activity at lower level of estradiol (10$^{-12}$ M, 10$^{-13}$ M). The relative affinities to the estrogen receptor were observed by allethrin and permethrin treatment, but not by fenvalerate. These results indicated that some of pyrethroid insecticides may modulate estrogen functions in human breast cancer cell. The action mechanisms of estrogen receptor mediated antiestrogenicity by allethrin and permethrin were postulated.

• 대한의생명과학회지
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• 제11권2호
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• pp.175-183
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• 2005

The two major isoflavones in soy, genistein and daidzein, are well known to prevent hormone-dependent cancers by their anti estrogenic activity. The exact molecular mechanisms for the protective action are, however, not provided yet. It has been reported that genistein and daidzein have a potential anticancer activity through their antiproliferative effect in many hormone-dependent cancer cell lines. Transforming growth $factor-\beta1(TGF-\beta1)$ has also been found to have cell growth inhibitory effect, especially in mammary epithelial cells. This knowledge led to a hypothetical mechanism that the soy isoflavones-induced growth inhibitory effect can be derived from the regulation of $TGF-\beta1$ and $TGF-\beta$ receptors. In order to test this hypothesis, the effects of the soy isoflavones at various concentrations and periods on the expression of $TGF-\beta1$and $TGF-\beta$ receptors were investigated by using Northern blot analysis in human breast carcinoma epithelial cell lines, an estrogen receptor positive cell line (MCF-7) and an estrogen receptor negative cell line (MDA-MB-231). As a result, only genistein has shown a profound dose-dependent effect on $TGF-\beta1$ expression in the $ER^+$ cell line within the range of doses tested, and the expression levels are correspondent to their inhibitory activities of cell growth. Moreover, daidzein showed down-regulated $TGF-\beta1$ expression at a low dose, the cell growth proliferation was promoted at the same condition. Therefore, antiproliferative activity of the soy isoflavones can be mediated by $TGF-\beta1$ expression, and the effects are mainly, if not all, occurred by ER dependent pathway. The expression of $TGF-\beta$ receptors was induced at a lower dose than the one for $TGF-{\beta}1$ induction regardless of the presence of ER, and the expression patterns are similar to those of the cell growth inhibition. These results indicated that the regulation of $TGF-\beta$ receptor expression as well, prior to $TGF-\beta1$ expression, may be involved in the antiproliferative activity of soy isoflavones. Little or no expression of $TGF-\beta$ receptors was found in the MCF-7 and MDA-MB-231 cells, suggesting refractory properties of the cells to growth inhibitory effect of the $TGF-\beta$. The soy isoflavones can seemingly restore the sensitivity of growth inhibitory responses to $TGF-\beta1$ by re-inducing $TGF-\beta$ receptors expression. In conclusions, our findings presented in this study show that the antitumorigenic activity of the soy isoflavones could be mediated by not only $TGF-\beta1$induction but $TGF-\beta$ receptor restoration. Thus, soy isoflavones could be good model molecules to develop new nonsteroidal antiestrogenic chemopreventive agents, associated with, regulation of $TGF-\beta$ and its receptors.

• Reproductive and Developmental Biology
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• 제38권1호
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• pp.35-40
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• 2014

Beta-catenin (CTNNB1, catenin (cadherin-associated protein), beta 1) is involved in various biological processes, including embryogenesis, tumorigenesis, angiogenesis and progression of metastasis. CTNNB1, as a multifunctional and oncogenic protein, has important roles in adhesion between Sertoli cells through an N-cadherin-dependent manner and in various cancer types through its over-activation. In addition, CTNNB1 can interact with estrogen/estrogen receptor alpha complex, which regulates the transcription of WNT (wingless-type MMTV integration site family)/CTNNB1 target genes. Recently, we investigated the functional roles and expression pattern of CTNNB1 during the morphological changes of embryonic gonads of chickens and the estrogen-dependent regulation of CTNNB1 in oviduct development and potential functions as a biomarker of CTNNB1 in human epithelial ovarian cancer using the chicken as a biological research model. Therefore, in this review, we provide a new insight of potential role of CTNNB1 in the development of the female reproductive tract during early embryogenesis and ovarian carcinogenesis of laying hen models.

• 한국동물학회지
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• 제37권3호
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• pp.377-384
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• 1994

The present study examines the inhibitow effect of progesterone (P) on luteinizing hormone $(LH)\beta$ subunit gene expression in anterior pituitary of ovariectomized, estradiol-treated adult rats. A single injection of P (1mg) further decreased the estradiol-Induced decrease in $LH\beta$ mRNA levels in ovariectomTzed rats in a time-dependent manner. p suppressed UIP mRNA levels at lower doses (0.1 and 1mg), but increased $LH\beta$ mRNA levels 81 a high dose (toms). The inhibitor action of P on $Uf\beta$ mRNA was restored when Ru486, a P receptor antagonist, was administered 1h before P treatment. These data clearly indicate that P inhibits gene expression of $LH\beta$ in the rift pituitary in a swersic manner with estrogen.

• Experimental and Molecular Medicine
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• 제50권11호
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• pp.10.1-10.11
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• 2018

Although early studies suggested that bladder cancer (BCa) is more prevalent in men than in women, muscle-invasive rates are higher in women than in men, suggesting that sex hormones might play important roles in different stages of BCa progression. In this work, we found that estrogen receptor beta ($ER{\beta}$) could increase BCa cell proliferation and invasion via alteration of miR-92a-mediated DAB2IP (DOC-2/DAB2 interacting protein) signals and that blocking miR-92a expression with an inhibitor could partially reverse $ER{\beta}$-enhanced BCa cell growth and invasion. Further mechanism dissection found that $ER{\beta}$ could increase miR-92a expression at the transcriptional level via binding to the estrogen-response-element (ERE) on the 5' promoter region of its host gene C13orf25. The $ER{\beta}$ up-regulated miR-92a could decrease DAB2IP tumor suppressor expression via binding to the miR-92a binding site located on the DAB2IP 3' UTR. Preclinical studies using an in vivo mouse model also confirmed that targeting this newly identified $ER{\beta}$/miR-92a/DAB2IP signal pathway with small molecules could suppress BCa progression. Together, these results might aid in the development of new therapies via targeting of this $ER{\beta}$-mediated signal pathway to better suppress BCa progression.

• Journal of Ginseng Research
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• 제43권4호
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• pp.527-538
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• 2019

Background: Ginsenoside Rg1 was shown to exert ligand-independent activation of estrogen receptor (ER) via mitogen-activated protein kinase-mediated pathway. Our study aimed to delineate the mechanisms by which Rg1 activates the rapid ER signaling pathways. Methods: ER-positive human breast cancer MCF-7 cells and ER-negative human embryonic kidney HEK293 cells were treated with Rg1 ($10^{-12}M$, $10^{-8}M$), $17{\beta}$-estradiol ($10^{-8}M$), or vehicle. Immunoprecipitation was conducted to investigate the interactions between signaling protein and ER in MCF-7 cells. To determine the roles of these signaling proteins in the actions of Rg1, small interfering RNA or their inhibitors were applied. Results: Rg1 rapidly induced $ER{\alpha}$ translocation to plasma membrane via caveolin-1 and the formation of signaling complex involving linker protein (Shc), insulin-like growth factor-I receptor, modulator of nongenomic activity of ER (MNAR), $ER{\alpha}$, and cellular nonreceptor tyrosine kinase (c-Src) in MCF-7 cells. The induction of extracellular signal-regulated protein kinase and mitogen-activated protein kinase kinase (MEK) phosphorylation in MCF-7 cells by Rg1 was suppressed by cotreatment with small interfering RNA against these signaling proteins. The stimulatory effects of Rg1 on MEK phosphorylation in these cells were suppressed by both PP2 (Src kinase inhibitor) and AG1478 [epidermal growth factor receptor (EGFR) inhibitor]. In addition, Rg1-induced estrogenic activities, EGFR and MEK phosphorylation in MCF-7 cells were abolished by cotreatment with G15 (G protein-coupled estrogen receptor-1 antagonist). The increase in intracellular cyclic AMP accumulation, but not Ca mobilization, in MCF-7 cells by Rg1 could be abolished by G15. Conclusion: Ginsenoside Rg1 exerted estrogenic actions by rapidly inducing the formation of ER containing signalosome in MCF-7 cells. Additionally, Rg1 could activate EGFR and c-Src ER-independently and exert estrogenic effects via rapid activation of membrane-associated ER and G protein-coupled estrogen receptor.