• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2008년도 Proceedings of the Convention
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• pp.55-74
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• 2008

Previously, we have shown that hypoxia, through HIF-1, induces ligand-independent $ER{\alpha}$ activation and the physical interaction of HIF-1 and $ER{\alpha}$. However, the effect of hypoxia on the transactivation of $ER{\beta}$ is not yet known. In the present study, we found that hypoxia activated the $ER{\beta}$-mediated transcriptional response in the HEK 293 cell line, as determined by the transient expression of$ER{\beta}$ and ER-responsive reporter plasmids. The hypoxia-induced estrogen response element-mediated transcriptional response was dependent on $ER{\beta}$ expression and was inhibited by the ER antagonist ICI 182,780. Transactivation of $ER{\beta}$ was induced by the expression of HIF-$1{\alpha}$ under normoxic conditions, as determined by the expression of oxygen-independent stable GFP-HIF-$1{\alpha}$. HIF-$1{\alpha}$-induced $ER{\beta}$ transactivation was abolished by the inhibition of HIF-$1{\alpha}$ activation. This was determined by using chemical inhibitors for the MAPK pathway. In addition, HIF-$1{\alpha}$ interacted with $ER{\beta}$ in a mammalian-two hybrid assay. We conclude that hypoxia activates $ER{\beta}$ in a ligand-independent manner, possibly through the interaction of HIF-$1{\alpha}$ and $ER{\beta}$.

• Asian Pacific Journal of Cancer Prevention
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• 제13권1호
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• pp.41-48
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• 2012

Introduction: Breast cancer is the second leading cancer in Korean women. To assess potential genetic associations between the prostate stem cell antigen (PSCA) gene in the chromosome 8q24 locus and breast cancer risk in Korean women, 13 SNPs were selected and associations with breast cancer risk were analyzed with reference to hormone receptor (HR) and menopausal status. Methods:We analyzed DNA extracted from buffy coat from 456 patients and 461 control samples, using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) based upon region-specific PCR followed by allelespecific single base primer extension reactions. Risks associated with PSCA genotypes and haplotypes were estimated with chi-square test (${\chi}^2$-test), and polytomous logistic regression models using odds ratios (OR) and 95% confidence intervals (CIs), by HR and menopausal status. Results: In case-control analysis, odds ratios (OR) of rs2294009, rs2294008, rs2978981, rs2920298, rs2976395, and rs2976396 were statistically significant only among women with estrogen receptor (ER) negative cancers, and those of rs2294008, rs2978981, rs2294010, rs2920298, rs2976394, rs10216533, and rs2976396 were statistically significant only in pre-menopausal women, and not in postmenopausal women. Risk with the TTGGCAA haplotype was significantly elevated in ER (-) status (OR= 1.48, 95% CI= 1.03~2.12, p<0.05). Especially risk of allele T of rs2294008 is significantly low in pre-menopausal breast cancer patients and AA genotype of rs2976395 in ER (-) status represents the increase of OR value. Conclusion: This report indicated for the first time that associations exist between PSCA SNPs and breast cancer susceptibility in Korean women, particularly those who are pre-menopausal with an estrogen receptor negative tumor status.

• 한국발생생물학회지:발생과생식
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• 제22권1호
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• pp.95-104
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• 2018

CREBZF (cAMP-response element binding protein zhangfei) is a member of ATF/CREB family, and which regulates various cellular functions by suppressing major factors with direct interaction. In this study, we have examined the expression of CREBZF on mouse endometrium during uterus estrous cycles and estrogen (E2) treatment. In uterus, CREBZF mRNA expression was higher than other organs and mRNA and protein of CREBZF was increased in proestrus phase and decreased in estrus phase. The expression of CREBZF in 3-weeks old mouse uterus was reduced by E2 injection in endometrium. In addition, the expression of progesterone receptor, a marker of E2 in ovariectomized mice was found to be strongly expressed in stroma, while CREBZF was only expressed in epithelium. Also, we conformed that E2-suppressed CREBZF was restored by co-injection of ICI 182,780, an estrogen receptor antagonist. Overall, these results suggest that CREBZF is regulated by estrogen and involved in ER signaling pathway in mouse uterus.

• 한국양식학회지
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• 제15권1호
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• pp.31-37
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• 2002

이 연구는 무지개송어, O. mykiss 간세포 배양을 이용해 합성화학물질인 2,4-Dichlorophenoxy acetic acid (2,4-D)가 vitellogenin (VTG) 합성과 estrogen (E$_2$) - estrogen receptor (ER) binding affinity에 미치는 영향을 조사하였다. 간세포는 2일간 전 배양한 후에 E, (2$\times$10$\^$-6/ M) 또는 2,4-D (10$\^$-9/∼10$\^$-6/ M)를 배지에 첨가해 5일간 배양한 후, VTG과 E$_2$-ER binding affinity를 SDS-PAGE와 ELISA를 이용해 각각 조사하였다. 사용된 2,4-D의 농도는 세포의 형태, 생존력 및 DNA 함량에는 영향을 미치지 않았다. 또한, 2,4-D는 VTG의 합성에도 어떠한 영향도 미치지 않았으나 E$_2$-ER binding affinity를 억제하였다. 이 binding affinity는 2,4-D의 농도가 증가할수록 증가하는 경향을 나타내어 10$\^$-7/과 10$\^$-6/ M에서 25%와 30%를 각각 억제하였다. 이 결과들은 비록 2,4-D가 VTG의 합성에는 영향을 미치지 않지만, ER에서 xeno-estrogenic contaminant로서 행동하는 것을 제시하였다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권18호
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• pp.7839-7842
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• 2014

Background: Breast cancer is the most common malignancy in women worldwide and the second most common cancer in females in India. Receptor status may be important for survival. Objective: To analyse and correlate the clinical and morphological parameters with receptor status in breast carcinoma patients in a tertiary care institution in Southern India. Materials and Methods: This retrospective study involved 320 patients of breast cancer diagnosed in an oncology hospital over a period of $3^{1/2}$ years. Data was analysed using SPSS Version 21. Results: Some 60.6% patients with breast carcinomas belonged to the age group of 40 to 60 years. The most common histological type was infiltrating ductal carcinoma, not otherwise specified, accounting for 84.4% of patients. On immunohistochemistry, estrogen receptor (ER) and progesterone receptor (PR) were expressed in 56.3% and 53.1% of cases, respectively. Conclusions: Breast cancers in India, a developing country, occur in younger women and tend to be more aggressive with lower rates of ER and PR expression and higher histological tumor grades. Both ER and PR status of the tumors had significant associations with the patient age, pathological TNM stage and histological tumor grade.

• 대한임상검사과학회지
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• 제36권2호
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• pp.185-192
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• 2004

Overexpressions of the estrogen receptors(ER), progesterone receptors(PR) and C-erbB-2 protein are important determiners of the response to chemotherapy in the breast cancer. For detecting ER, PR and C-erbB-2, immunohistochemistry are currently regarded as standard method. The purposes of this study compared to histologic grade and expression of the ER, PR and C-erbB-2 in breast cancer. We examined overexpression of ER, PR and C-erbB-2 protein in 84 breast carcinomas by using immunohistochemical stains. The following results were obtained. For histologic grade, 10 cases(11.9%) showed carcinoma in situ, 16 cases(19%) showed grade I, 36 cases (42.9%) showed grade II, and 22 cases(26.2%) showed grade III among the 84 test samples. The average positive rate ER and PR was 63%, 46% showed carcinoma in situ, 80%, 60% showed grade I, 64%, 41% showed grade II, 34%, 23% showed grade III, respectively. The induction of PR increased when induction of ER increased, thus showing significant relationship(p<0.05). The expression of C-erbB-2 protein was 9 cases(10.7%) in one positive(1+), 9 cases(10.7%) in two positive(2+), and 9 cases(10.7%) in three positive(3+). C-erbB-2 protein expression showed no statistical significance. In conclusion, ER and PR positive rates were inversely associated with histologic grades significantly(p<0.05). C-erbB-2 showed no significant difference with histologic grade. However ER, PR and C-erbB-2 showed significant relationship with each other(p<0.05). Therefore, these findings might be an important prognostic factor and might be arranged as a regular pathological examination in cases of breast cancer.

• Environmental Analysis Health and Toxicology
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• 제20권3호
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• pp.249-258
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• 2005

Blood pressure, obesity and bone mineral density are multifactorial traits influenced by genetic factor. The purpose of this study was to clarify the association between three genetic polymorphisms in the estrogen receptor-$\alpha$ (ER -$\alpha$) gene and essential hypertension in korean population. One hundred and seventy-one people including 90 normotensives and 81 essential hypertentives were recruited. Among genetic polymorphisms studied, the Xba I RFLP in the intron 1 of this gene polymorphism was significantly associated with essential hypertension in women, suggesting the sexual dimorphism in genetic effect (P (<) 0.05). Further studied suggest that a larger sample size of this study are needed.

• Toxicological Research
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• 제19권4호
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• pp.325-330
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• 2003

The effects of estrogen on apoptosis induced by 2,3,7,8-tetrachlorodibenzo-p-doxin (TCDD) were examined in cultured MCF-7 cells. TCDD stimulated apoptosis and inhibited the expression of bcl-2 gene in MCF-7 cells grown in the media supplemented with 10% fetal bovine serum. However, TCDD failed to induce apoptosis if cells were grown in the media deprived of all estrogen-like compounds. Removal of estrogen-like compounds from the growth media also led to the activation of bcl-2 gene expression in cells treated with TCDD. Combined treatment of estrogen with TCDD abrogated the binding of Aryl hydrocarbon Receptor (AhR)-TCDD complex to Dioxin response element (DRE) of bcl-2 gene leading to the inhibition of bcl-2 gene expression as well as stimulation of apoptosis. The present study suggests that the binding of estrogen receptor (ER)-estrogen complex to the estrogen responsive element (E) interferes with the binding of AhR- TCDD complex to the DRE and inhibits the bcl-2 expression.

• Asian Pacific Journal of Cancer Prevention
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• 제17권7호
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• pp.3363-3367
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• 2016

Background: Breast cancer (BC) is a major health issue worldwide as well as in Pakistan. All women belonging to any race, ethnicity or lineage are in danger of developing breast cancer. Significant factors influencing the development of breast malignancies are the genetic background, environmental conditions, reproductive parameters, the consequences of female hormones both intrinsic and extrinsic, alteration of immune status, and biologic determinants. Materials and Methods: Overall 150 biopsy proven patients were included in the study. Samples were submitted for histopathology and determination of estrogen and progesterone receptor expression and HER-2/neu status. Associations with other characteristics like age, tumor stage, node involvement, histological grade were also studied. Results: Mean age at presentation was 46.7 years. The majority had invasive ductal carcinoma, 100 (84.7%), and were in stage pT3, 54 (45.7%). Important relationships (P<0.05) were found among ER, PR positivity, and Her 2 neu overexpression. However, no noteworthy link was identified amongst ER, PR, Her 2 neu and tumor grade, stage, age, lymph node involvement except for the menopausal status. Conclusions: In summary, breast cancer patients featured an advanced stage of disease, more lymph node involvement, and moderately high grade tumors and with more estrogen, progesterone receptor and HER-2 positive tumors.

• Asian Pacific Journal of Cancer Prevention
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• 제17권7호
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• pp.3223-3228
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• 2016

Reports indicate that 15-deoxy-delta-12,14-prostaglandin-J2 (15d-PGJ2) has anticancer activities, but its mechanisms of action have yet to be fully elucidated. We therefore investigated the effects of 15d-PGJ2 on the human breast cancer cell lines, MCF-7 (estrogen receptor $ER{\alpha}+/ER{\beta}+$) and MDA-MB-231 ($ER{\alpha}-/ER{\beta}+$). Cellular proliferation and cytotoxicity were determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and lactate dehydrogenase (LDH) assays while apoptosis was determined by fluorescence microscopy and flow cytometry using annexin V-propidium iodide (PI) staining. ER expression was determined by Western blotting. Intracellular calcium was stained with Fluo-4 AM while intracellular caspase activities were detected with Caspase-$FLICA(R)$ and measured by flow cytometry. We showed that 15d-PGJ2 caused a significant increase in apoptosis in MCF-7 and MDA-MB-231 cells. $ER{\alpha}$ protein expression was reduced in treated MCF-7 cells but pre-incubation with the $ER{\alpha}$ inhibitor' ICI 182 780' did not affect the percentage of apoptotic cells. The expression of $ER{\beta}$ was unchanged in both cell lines. In addition, 15d-PGJ2 increased intracellular calcium ($Ca^{2+}$) staining and caspase 8, 9 and 3/7 activities. We therefore conclude that 15d-PGJ2 induces caspase-dependent apoptosis that is associated with an influx of intracellular $Ca^{2+}$ with no involvement of ER signaling.