• The Korean Journal of Nuclear Medicine
• /
• v.15 no.2
• /
• pp.53-57
• /
• 1981

The estrogen and progesterone receptors which are bound to the cytoplasmic protein of cancer cells were measured in 20 patients with the early breast cancer by means of radioimmunoassay using charcoal. 1. The Patients with estrogen receptor positive were 13 (65%) of 20 cases and with progestrone receptor positive were 7 cases (35%) in the early breast cancer. 2. Coexistence of estrogen and progesterone receptor positive was noted in 7 cases (35%). The cases of estrogen receptor positive and progesterone receptor negative were 6 cases (33.3%), while there were no cases of estrogen receptor negative with progestrone receptor positive. 3. Coincidence of estrogen and progesterone negative was notied in 7 cases(35%). Conclusively, it is considered that the measurement of estrogen and progesterone receptors has relevance as predictive value, in the response to hormonal manipulations and chemotherapy for breast cancer patients.

• Asian Pacific Journal of Cancer Prevention
• /
• v.14 no.4
• /
• pp.2371-2375
• /
• 2013

Breast cancer is one of the most common malignancies in women around the world. Among the various hormonal types of breast cancer, those that are estrogen receptor (ER) positive account for the majority. Among the estrogen related receptors, estrogen related receptor ${\alpha}$ is known to have a potential role in breast cancer and is one of the therapeutic target. Hence, prediction of novel ligands interact with estrogen related receptor alpha is therapeutically important. The present study, aims at prediction and analysis of ligands from the KEGG COMPOUND database (containing 10,739 entries) able to interact against estrogen receptor alpha using a similarity search and molecular docking approach.

• Archives of Pharmacal Research
• /
• v.27 no.5
• /
• pp.554-561
• /
• 2004

Trichostatin A, an antifungal antibiotics, and HC-toxin are potent and specific inhibitors of histone deacetylase activity. Histone deacetylase inhibitors are new class of chemotherapeutic drugs able to induce tumor cell apoptosis and/or cell cycle arrest. In this study, the antiproliferative activities of trichostatin A and HC-toxin were compared between estrogen receptor positive human breast cancer cell MCF-7 and estrogen receptor negative human breast cancer cell MDA-MB-468. Trichostatin A and HC-toxin showed potent antiproliferative activity in both MCF-7 and MDA-MB-468 cells. In MCF-7 cells that contain high level estrogen receptor, trichostatin A and HC-toxin brought about three-times more potent cell growth inhibitory effect than estrogen receptor negative MDA-MB-468 cells. Both trichostatin A and HC-toxin showed cell cycle arrest at G$_2$/M phases of MCF-7 and MDA-MB-468 cells in a dose- and time- depen- dent manner. Trichostatin A and HC-toxin also induced apoptosis from MCF-7 and MDA-MB-468 cells in a dose- and time-dependent manner. Results of this study suggested that antipro-liferative effects of trichostatin A and HC-toxin might be involved in estrogen receptor signaling pathway, but cell cycle arrest and apoptosis of trichostatin A and HC-toxin might not be involved in estrogen receptor system of human breast cancer cells.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.27 no.3
• /
• pp.306-312
• /
• 2013

Costunolide ($C_{15}H_{20}O_2$) is a sesquiterpene lactone that was isolated from many herbal medicines and it has diverse effects (anti-viral, anti-fungal, and anti-inflammatory) according to previous reports. However, the anti-cancer effects of Costunolide and its mechanism of actions are not well known in estrogen receptor positive breast cancer. In this study, we observed that costunolide suppresses cell growth in estrogen receptor positive MCF-7 breast cancer cells as shown by MTT assay and soft agar colony formation assay. To examine the mechanism by which costunolide inhibits MCF-7 cell growth, we performed FACS analysis. We found that costunolide induced G2/M and S cell cycle arrest, and regulated cycle-related protein expression. In addition, costunolide inhibited ERK signaling pathway and induced autophagy. Therefore, costunolide might be a good and useful chemotherapy agent for estrogen receptor positive breast cancer patients.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.7
• /
• pp.3041-3044
• /
• 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.

• Toxicological Research
• /
• v.27 no.2
• /
• pp.85-93
• /
• 2011

Selective estrogen receptor modulators (SERMs) are synthetic molecules which bind to estrogen receptors (ER) and can modulate its transcriptional capabilities in different ways in diverse estrogen target tissues. Tamoxifen, the prototypical SERM, is extensively used for targeted therapy of ER positive breast cancers. Unfortunately, the use of tamoxifen is associated with acquired resistance and some undesirable side effects. This study investigated the availability of the conventional SERMs on the TAM-resistance breast cancer cells. SERMs showed more effectiveness in MCF-7 cells than tamoxifen resistant cells, except toremifene and ospemifene. Especially, toremifene was more efficacious in tamoxifen resistant cells than MCF-7. Ospemifene had similar cytotoxic activity on the two types of breast cancers. The other SERMs used in this experiment didn't inhibit efficiently the proliferation of tamoxifen resistant cells. These results support the possibility to usage of toremifene on tamoxifen resistant cancer. The effectiveness by toremifene on tamoxifen resistant cells might be different pathways from the apoptosis and the autophagy. Further study should be needed to elucidate the underlying mechanism of effect of toremifene on tamoxifen resistant cancer.

• Archives of Pharmacal Research
• /
• v.20 no.6
• /
• pp.579-585
• /
• 1997

To gain further insight into the mechanism of action of antiestrogens, we examined the interaction of antiestrogen with the estrogen receptor system and with estrogen- noncompetable antiestrogen binding sites. In addition to binding directly to the estrogen receptor, antiestrogens can be found associated with binding sites that are distinct from the estrogen receptor. In contrast to the restriction of estrogen receptors to estrogen target cells, such as those of uterus and mammary glands, antiestrogen binding sites are present in equal amounts in estrogen receptor-positive and -negative human breast cancer cell lines, such as MCF-7, T47D, and MDA-MB-231 that differ markedly in their sensitivity to antiestrogens. In order to gain greater insight into the role of these antiestrogen binding sites in the action of antiestrogens, we have examined the biopotency of different antiestrogens for the antiestrogen binding sites and that is CI628 > tamoxifen > trans-hydroxy tamoxifen > CI628M > H1285 > LY117018. This order of affinities does not parallel the affinity of these compounds for the estrogen receptor nor the potency of these compounds as antiestrogens. Indeed, compounds with high affinity for the estrogen receptor and greatest antiestrogenic potency have low affinities for these antiestrogen binding sites. Antiestrogenic potency correlates best with estrogen receptor affinity and not with affinity for antiestrogen binding sites. In summary, our findings suggested that interaction with the estrogen receptor is most likely the mechanism through which antiestrogens evoke their growth inhibitory effects.

• Asian Pacific Journal of Cancer Prevention
• /
• v.14 no.7
• /
• pp.4049-4052
• /
• 2013

Resistance to chemotherapy treatment, which may lead to limited efficacy of systemic therapy in breast cancer patients, is multifactorial. Among the mechanisms of resistance to chemotherapy treatment, there are those closely related to estrogen receptor ${\alpha}$, P-glycoprotein, multidrug resistance-related protein, glutathione S-transferase pi and topoisomerase-II. $ER{\alpha}$ is ligand-activated transcription factor that regulates gene expression and plays a critical role in endocrine signaling. In previous preclinical and clinical studies, positive $ER{\alpha}$ expression in breast cancer cells was correlated with decreased sensitivity to chemotherapy. This article reviews current knowledge on the predictive value of $ER{\alpha}$ with regard to response to chemotherapy. Better understanding of its role may facilitate patient selection of therapeutic regimens and lead to optimal clinical outcomes.

• Journal of Breast Cancer
• /
• v.21 no.4
• /
• pp.415-424
• /
• 2018

Purpose: Triple-positive breast cancer is defined by estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 (HER2) positivity. Several systemic breast cancer therapies target hormonal and HER2 responsiveness. We compared clinical outcomes of triple-positive disease with those of HER2-enriched and luminal HER2-negative disease and investigated the clinical efficacy of anti-HER2 therapy for triple-positive disease. Methods: We retrospectively compared overall and recurrence-free survival among cases included in the Korean Breast Cancer Society (KBCS) and Seoul St. Mary's Hospital breast cancer registries and the therapeutic efficacy of trastuzumab for triple-positive and HER2-enriched cases. Results: KBCS registry data (2006-2010; median follow-up, 76 months) indicated that patients with triple-positive breast cancer had intermediate survival between those with luminal A and HER2-enriched subtypes (p<0.001). Trastuzumab did not improve overall survival among patients with triple-positive breast cancer (p=0.899) in contrast to the HER2-enriched subtype (p=0.018). Seoul St. Mary's Hospital registry data indicated similar recurrence-free survival outcomes (p<0.001) and a lack of improvement with trastuzumab among patients with triple-positive breast cancer (median follow-up, 33 months; p=0.800). Multivariate analysis revealed that patients with triple-positive breast cancer had better overall survival than those with HER2-enriched disease and similar survival as those with the luminal A subtype (triple-positive: hazard ratio, 1.258, p=0.118; HER2-enriched: hazard ratio, 2.377, p<0.001). Conclusion: Our findings showed that anti-HER2 therapy was less beneficial for treatment of triple-positive breast cancer than for HER2-enriched subtypes of breast cancer, and the triple-positive subtype had a distinct prognosis.

• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.10
• /
• pp.5047-5052
• /
• 2012

Introduction: Breast cancer is the most common malignancy of women in Kashmir. This study was conducted with the objective of assessing hormone receptor positivity and its correlation with age at diagnosis, tumor size, histological grade and lymph node metastasis. Materials and Methods: 132 newly diagnosed cases of invasive breast cancer diagnosed at the Department of Pathology, SKIMS, Srinagar, J&K, were included after excluding biopsies, in-situ lesions and recurrence cases. Results: Mean age of the patients was 48.2 years, 59.1% being ${\leq}50$ years of age. Mean duration of symptoms was 6.32 months. Most lesions (65.1%) were 2-5 cm and 16.7% were ${\geq}5.0$ cm in greatest dimension. The predominant (80.3%) morphology was IDC-NOS. The majority of the cases presented as grade II (52.1%) lesions and lymph node involvement was present in 65.2%. ER and PR were positive in 66.3% and 63.4% cases, respectively, increasing with rising age. High grade lesions and larger size tumors were more likely to be ER and PR negative. No correlation was found between ER/PR status and lymph node metastasis. Conclusions: ER and PR expression in breast cancers in the current study was found to be higher than studies done in India/Asia but lower than studies conducted in the West, even on Indian/Asian immigrants. Markedly lower receptor expression in Indian/Asian studies is likely due to preanalytic variables, thresholds for positivity, and interpretation criteria. American Society of Clinical Oncology/College of American Pathologists Guideline Recommendations for Immunohistochemical Testing of Estrogen and Progesterone Receptors in Breast Cancer are strongly advocated for standardization of receptor evaluation and for clinical management of breast cancer patients to provide best therapeutic options.