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Al-Kabariti AY, Abbas MA. Progress in the Understanding of Estrogen Receptor Alpha Signaling in Triple-Negative Breast Cancer: Reactivation of Silenced ER-α and Signaling through ER-α36. Mol Cancer Res 2023; 21:1123-1138. [PMID: 37462782 DOI: 10.1158/1541-7786.mcr-23-0321] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 06/21/2023] [Accepted: 07/14/2023] [Indexed: 11/02/2023]
Abstract
Triple-negative breast cancer (TNBC) is an aggressive tumor that accounts for approximately 15% of total breast cancer cases. It is characterized by poor prognosis and high rate of recurrence compared to other types of breast cancer. TNBC has a limited range of treatment options that include chemotherapy, surgery, and radiation due to the absence of estrogen receptor alpha (ER-α) rendering hormonal therapy ineffective. However, possible targets for improving the clinical outcomes in TNBC exist, such as targeting estrogen signaling through membranous ER-α36 and reactivating silenced ER-α. It has been shown that epigenetic drugs such as DNA methyltransferase and histone deacetylase inhibitors can restore the expression of ER-α. This reactivation of ER-α, presents a potential strategy to re-sensitize TNBC to hormonal therapy. Also, this review provides up-to-date information related to the direct involvement of miRNA in regulating the translation of ER-α mRNA. Specific epi-miRNAs can regulate ER-α expression indirectly by post-transcriptional targeting of mRNAs of enzymes that are involved in DNA methylation and histone deacetylation. Furthermore, ER-α36, an alternative splice variant of ER-α66, is highly expressed in ER-negative breast tumors and activates MAPK/ERK pathway, promoting cell proliferation, escaping apoptosis, and enhancing metastasis. In the future, these recent advances may be helpful for researchers working in the field to obtain novel treatment options for TNBC, utilizing epigenetic drugs and epi-miRNAs that regulate ER-α expression. Also, there is some evidence to suggest that drugs that decrease the expression of ER-α36 may be effective in treating TNBC.
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Affiliation(s)
- Aya Y Al-Kabariti
- Department of Biopharmaceutics and Clinical Pharmacy, Faculty of Pharmacy, Al-Ahliyya Amman University, Amman, Jordan
- Pharmacological and Diagnostic Research Centre, Al-Ahliyya Amman University, Amman, Jordan
| | - Manal A Abbas
- Pharmacological and Diagnostic Research Centre, Al-Ahliyya Amman University, Amman, Jordan
- Department of Medical Laboratory Sciences, Faculty of Allied Medical Sciences, Al-Ahliyya Amman University, Amman, Jordan
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Notas G, Panagiotopoulos A, Vamvoukaki R, Kalyvianaki K, Kiagiadaki F, Deli A, Kampa M, Castanas E. ERα36-GPER1 Collaboration Inhibits TLR4/NFκB-Induced Pro-Inflammatory Activity in Breast Cancer Cells. Int J Mol Sci 2021; 22:ijms22147603. [PMID: 34299224 PMCID: PMC8303269 DOI: 10.3390/ijms22147603] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 07/06/2021] [Accepted: 07/09/2021] [Indexed: 12/14/2022] Open
Abstract
Inflammation is important for the initiation and progression of breast cancer. We have previously reported that in monocytes, estrogen regulates TLR4/NFκB-mediated inflammation via the interaction of the Erα isoform ERα36 with GPER1. We therefore investigated whether a similar mechanism is present in breast cancer epithelial cells, and the effect of ERα36 expression on the classic 66 kD ERα isoform (ERα66) functions. We report that estrogen inhibits LPS-induced NFκB activity and the expression of downstream molecules TNFα and IL-6. In the absence of ERα66, ERα36 and GPER1 are both indispensable for this effect. In the presence of ERα66, ERα36 or GPER1 knock-down partially inhibits NFκB-mediated inflammation. In both cases, ERα36 overexpression enhances the inhibitory effect of estrogen on inflammation. We also verify that ERα36 and GPER1 physically interact, especially after LPS treatment, and that GPER1 interacts directly with NFκB. When both ERα66 and ERα36 are expressed, the latter acts as an inhibitor of ERα66 via its binding to estrogen response elements. We also report that the activation of ERα36 leads to the inhibition of breast cancer cell proliferation. Our data support that ERα36 is an inhibitory estrogen receptor that, in collaboration with GPER1, inhibits NFκB-mediated inflammation and ERα66 actions in breast cancer cells.
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Affiliation(s)
- George Notas
- Correspondence: ; Tel.: +30-2810-3945-56; Fax: +30-2810-3945-81
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Mahboobifard F, Dargahi L, Jorjani M, Ramezani Tehrani F, Pourgholami MH. The role of ERα36 in cell type-specific functions of estrogen and cancer development. Pharmacol Res 2021; 163:105307. [DOI: 10.1016/j.phrs.2020.105307] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 11/05/2020] [Accepted: 11/09/2020] [Indexed: 02/07/2023]
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Thiebaut C, Konan HP, Guerquin MJ, Chesnel A, Livera G, Le Romancer M, Dumond H. The Role of ERα36 in Development and Tumor Malignancy. Int J Mol Sci 2020; 21:E4116. [PMID: 32526980 PMCID: PMC7312586 DOI: 10.3390/ijms21114116] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 06/03/2020] [Accepted: 06/04/2020] [Indexed: 02/06/2023] Open
Abstract
Estrogen nuclear receptors, represented by the canonical forms ERα66 and ERβ1, are the main mediators of the estrogen-dependent pathophysiology in mammals. However, numerous isoforms have been identified, stimulating unconventional estrogen response pathways leading to complex cellular and tissue responses. The estrogen receptor variant, ERα36, was cloned in 2005 and is mainly described in the literature to be involved in the progression of mammary tumors and in the acquired resistance to anti-estrogen drugs, such as tamoxifen. In this review, we will first specify the place that ERα36 currently occupies within the diversity of nuclear and membrane estrogen receptors. We will then report recent data on the impact of ERα36 expression and/or activity in normal breast and testicular cells, but also in different types of tumors including mammary tumors, highlighting why ERα36 can now be considered as a marker of malignancy. Finally, we will explain how studying the regulation of ERα36 expression could provide new clues to counteract resistance to cancer treatments in hormone-sensitive tumors.
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Affiliation(s)
- Charlène Thiebaut
- Université de Lorraine, CNRS, CRAN, F-54000 Nancy, France; (C.T.); (A.C.)
| | - Henri-Philippe Konan
- Université de Lyon, F-69000 Lyon, France; (H.-P.K.); (M.L.R.)
- INSERM U1052, Centre de Recherche en Cancérologie de Lyon, F-69000 Lyon, France
- CNRS UMR5286, Centre de Recherche en Cancérologie de Lyon, F-69000 Lyon, France
| | - Marie-Justine Guerquin
- Laboratory of Development of the Gonads, UMRE008 Genetic Stability Stem Cells and Radiation, Université de Paris, Université Paris Saclay, CEA, F-92265 Fontenay aux Roses, France; (M.-J.G.); (G.L.)
| | - Amand Chesnel
- Université de Lorraine, CNRS, CRAN, F-54000 Nancy, France; (C.T.); (A.C.)
| | - Gabriel Livera
- Laboratory of Development of the Gonads, UMRE008 Genetic Stability Stem Cells and Radiation, Université de Paris, Université Paris Saclay, CEA, F-92265 Fontenay aux Roses, France; (M.-J.G.); (G.L.)
| | - Muriel Le Romancer
- Université de Lyon, F-69000 Lyon, France; (H.-P.K.); (M.L.R.)
- INSERM U1052, Centre de Recherche en Cancérologie de Lyon, F-69000 Lyon, France
- CNRS UMR5286, Centre de Recherche en Cancérologie de Lyon, F-69000 Lyon, France
| | - Hélène Dumond
- Université de Lorraine, CNRS, CRAN, F-54000 Nancy, France; (C.T.); (A.C.)
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Mahboobifard F, Bidari-Zerehpoosh F, Davoudi Z, Panahi M, Dargahi L, Pourgholami MH, Sharifi G, Izadi N, Jorjani M. Expression patterns of ERα66 and its novel variant isoform ERα36 in lactotroph pituitary adenomas and associations with clinicopathological characteristics. Pituitary 2020; 23:232-245. [PMID: 32026205 DOI: 10.1007/s11102-020-01029-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
PURPOSE The regulatory effects of estradiol on pituitary homeostasis have been well documented. However, the expression patterns of ERα66 and ERα36 and their correlations with the clinical course of postoperative prolactinoma tumors remain unclear. METHODS The expression of ERα36, ERα66, Ki67, p53, and CD31 were determined by immunohistochemistry in 62 prolactinoma patients. Snap-frozen tumors and normal pituitaries were also examined by western blotting for estrogen receptor detection. RESULTS A broad expression of ERα36 was identified in normal pituitaries. The median scores of ERα36 and ERα66 expression were 8 and 6 in normal pituitaries and 4 and 0 in tumors, respectively. Four phenotypes of ERα36 and ERα66 expression were explored in tumors with regard to sex, invasiveness, dopamine resistance, and recurrence. Low ERα36 expression was associated with tumor invasion and increased Ki67. Low ERα66 expression was associated with tumor invasion, dopamine-agonist resistance, and enhanced tumor size. Multivariable logistic regression analysis showed that low ERα36 expression is an independent risk factor for invasiveness. The significant inverse association of ERα66 with invasiveness, dopamine resistance, and tumor size remained significant after adjustment for sex as a potential confounder. After controlling for sex, the low ERα66/low ERα36 phenotype was 6.24 times more prevalent in invasive tumors than in noninvasive tumors. Although the decreasing trend of CD31 expression from surrounding nontumoral lactotroph adenomas to tumors was similar to that of the estrogen receptors, a significant correlation was not observed here. CONCLUSION The decreasing trends of ERα36 and ERα66 expression from normal pituitaries to tumors are associated with aggressive clinical behavior.
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Affiliation(s)
- Fatemeh Mahboobifard
- Department of Pharmacology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Farahnaz Bidari-Zerehpoosh
- Department of Pathology, Loghman Hakim Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Zahra Davoudi
- Skull Base Research Center, Loghman Hakim Hospital, Shahid Beheshti University of Medical Science, Tehran, Iran
| | - Mahshid Panahi
- Department of Pathology, Firoozgar Hospital, Iran University of Medical Sciences, Tehran, Iran
| | - Leila Dargahi
- Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad H Pourgholami
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Gieve Sharifi
- Department of Neurosurgery, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Neda Izadi
- Department of Epidemiology, School of Public Health and Safety, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Masoumeh Jorjani
- Department of Pharmacology and Neurobiology Research Center, School of Medicine, Shahid Beheshti University of Medical Sciences, Velenjak, Tehran, Iran.
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Qu C, Ma J, Zhang Y, Han C, Huang L, Shen L, Li H, Wang X, Liu J, Zou W. Estrogen receptor variant ER-α36 promotes tamoxifen agonist activity in glioblastoma cells. Cancer Sci 2019; 110:221-234. [PMID: 30417588 PMCID: PMC6317923 DOI: 10.1111/cas.13868] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Revised: 10/15/2018] [Accepted: 10/30/2018] [Indexed: 12/20/2022] Open
Abstract
Glioblastoma (GBM) is a highly infiltrative and malignant primary brain tumor. Despite aggressive therapy, patients with GBM have a dismal prognosis with median survival of approximately 1 year. Tamoxifen (TAM), a selective estrogen receptor modulator (SERM), has been used to treat GBM for many years. ER‐α36 is a novel variant of estrogen receptor‐alpha66 (ER‐α66) and can mediate cell proliferation through estrogen or anti‐estrogen signaling in different cancer cells. Previously, we found that ER‐α36 was highly expressed in GBM and was involved in the tamoxifen sensitivity of glioblastoma cells. However, the molecular mechanism responsible has not been well established. Here, we found that ER‐α36 is highly expressed in glioblastoma specimens. We further found that ER‐α36 knockdown increased sensitivity of glioblastoma U87 cells to TAM and decreased autophagy in these cells. However, ER‐α36 overexpression decreased TAM sensitivity and induced autophagy. We also established TAM‐resistant glioblastoma U251 cells by a long‐term culture in TAM‐containing medium and found that TAM‐resistant cells showed a six‐fold increase of ER‐α36 mRNA expression and elevated basal autophagy. ER‐α36 knockdown in these TAM‐resistant cells restored TAM sensitivity. In addition, we recapitulated the physiologically relevant tumor microenvironment in an integrated microfluidic device, and U87 cells were treated with a gradient of TAM. We found that ER‐α36 expression is consistent with autophagy protein P62 in a three‐dimensional microenvironment. In summary, these results indicate that ER‐α36 contributes to tamoxifen resistance in glioblastoma cells presumably through regulation of autophagy.
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Affiliation(s)
- Chao Qu
- College of Life Science, Liaoning Normal University, Dalian, China.,Regenerative Medicine Center, First Affiliated Hospital of Dalian Medical University, Dalian, China.,Department of Pharmacological and Toxicological Research Centre, No. 210 Hospital of Chinese People's Liberation Army, Dalian, China
| | - Jingyun Ma
- Regenerative Medicine Center, First Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Yejun Zhang
- College of Life Science, Liaoning Normal University, Dalian, China
| | - Chao Han
- Regenerative Medicine Center, First Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Liang Huang
- College of Life Science, Liaoning Normal University, Dalian, China
| | - Liming Shen
- Regenerative Medicine Center, First Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Hongyan Li
- College of Life Science, Liaoning Normal University, Dalian, China
| | - Xiaobo Wang
- Department of Pharmacological and Toxicological Research Centre, No. 210 Hospital of Chinese People's Liberation Army, Dalian, China
| | - Jing Liu
- Regenerative Medicine Center, First Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Wei Zou
- College of Life Science, Liaoning Normal University, Dalian, China
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7
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Shen Y, Zhong J, Liu J, Liu K, Zhao J, Xu T, Zeng T, Li Z, Chen Y, Ding W, Wen G, Zu X, Cao R. Protein arginine N-methyltransferase 2 reverses tamoxifen resistance in breast cancer cells through suppression of ER-α36. Oncol Rep 2018; 39:2604-2612. [PMID: 29620287 PMCID: PMC5983932 DOI: 10.3892/or.2018.6350] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Accepted: 03/28/2018] [Indexed: 02/07/2023] Open
Abstract
Breast cancer is one of the most common malignancies in females, and 17β-estradiol (E2)/estrogen receptor α (ERα) signaling plays an important role in the initiation and progression of breast cancer. The role of the ER-α subtype and its co-regulator in the initiation of breast cancer and the occurrence of tamoxifen resistance remains to be further elucidated. In our previous studies, protein arginine N-methyltransferase 2 (PRMT2), a co-regulator of estrogen receptor-α (ER-α), was confirmed to interact with ER-α66 and has the ability to inhibit cell proliferation in breast cancer cells. In the present study, we found that tamoxifen treatment induced a decrease in PRMT2 and an increase in ER-α36 as well as ER-α36-mediated non-genomic effect in MDA-MB-231 cells, which were relatively resistant to tamoxifen by contrast to MCF-7 cells. Moreover, PRMT2 was able to interact with ER-α36 directly, suppress ER-α36 and downstream PI3K/Akt and MAPK/ERK signaling, reversing the tamoxifen resistance of breast cancer cells. The present study may be meaningful for understanding the role of PRMT2 in breast cancer progression and for developing a new endocrine therapeutic strategy for breast cancer patients with tamoxifen resistance.
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Affiliation(s)
- Yingying Shen
- Institute of Clinical Medicine, The First Affiliated Hospital of University of South China, Hengyang, Hunan 421001, P.R. China
| | - Jing Zhong
- Institute of Clinical Medicine, The First Affiliated Hospital of University of South China, Hengyang, Hunan 421001, P.R. China
| | - Jianghua Liu
- Institute of Clinical Medicine, The First Affiliated Hospital of University of South China, Hengyang, Hunan 421001, P.R. China
- Department of Metabolism and Endocrinology, The First Affiliated Hospital of University of South China, Hengyang, Hunan 421001, P.R. China
| | - Kehuang Liu
- Department of Metabolism and Endocrinology, The First Affiliated Hospital of University of South China, Hengyang, Hunan 421001, P.R. China
| | - Jun Zhao
- Department of Metabolism and Endocrinology, The First Affiliated Hospital of University of South China, Hengyang, Hunan 421001, P.R. China
| | - Ting Xu
- Department of Metabolism and Endocrinology, The First Affiliated Hospital of University of South China, Hengyang, Hunan 421001, P.R. China
| | - Ting Zeng
- Department of Metabolism and Endocrinology, The First Affiliated Hospital of University of South China, Hengyang, Hunan 421001, P.R. China
| | - Zhimei Li
- Department of Metabolism and Endocrinology, The First Affiliated Hospital of University of South China, Hengyang, Hunan 421001, P.R. China
| | - Yajun Chen
- Department of Metabolism and Endocrinology, The First Affiliated Hospital of University of South China, Hengyang, Hunan 421001, P.R. China
| | - Wenjun Ding
- Institute of Clinical Medicine, The First Affiliated Hospital of University of South China, Hengyang, Hunan 421001, P.R. China
| | - Gebo Wen
- Institute of Clinical Medicine, The First Affiliated Hospital of University of South China, Hengyang, Hunan 421001, P.R. China
| | - Xuyu Zu
- Institute of Clinical Medicine, The First Affiliated Hospital of University of South China, Hengyang, Hunan 421001, P.R. China
| | - Renxian Cao
- Institute of Clinical Medicine, The First Affiliated Hospital of University of South China, Hengyang, Hunan 421001, P.R. China
- Department of Metabolism and Endocrinology, The First Affiliated Hospital of University of South China, Hengyang, Hunan 421001, P.R. China
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Miller MM, McMullen PD, Andersen ME, Clewell RA. Multiple receptors shape the estrogen response pathway and are critical considerations for the future of in vitro-based risk assessment efforts. Crit Rev Toxicol 2017; 47:564-580. [DOI: 10.1080/10408444.2017.1289150] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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9
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Pugach EK, Blenck CL, Dragavon JM, Langer SJ, Leinwand LA. Estrogen receptor profiling and activity in cardiac myocytes. Mol Cell Endocrinol 2016; 431:62-70. [PMID: 27164442 PMCID: PMC4899180 DOI: 10.1016/j.mce.2016.05.004] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/30/2015] [Revised: 04/14/2016] [Accepted: 05/05/2016] [Indexed: 01/01/2023]
Abstract
Estrogen signaling appears critical in the heart. However a mechanistic understanding of the role of estrogen in the cardiac myocyte is lacking. Moreover, there are multiple cell types in the heart and multiple estrogen receptor (ER) isoforms. Therefore, we studied expression, localization, transcriptional and signaling activity of ERs in isolated cardiac myocytes. We found only ERα RNA (but no ERβ RNA) in cardiac myocytes using two independent methods. The vast majority of full-length ERα protein (ERα66) localizes to cardiac myocyte nuclei where it is competent to activate transcription. Alternate isoforms of ERα encoded by the same genomic locus (ERα46 and ERα36) have differential transcriptional activity in cardiac myocytes but also primarily localize to nuclei. In contrast to other reports, no ERα isoform is competent to activate MAPK or PI3K signaling in cardiac myocytes. Together these data support a role for ERα at the level of transcription in cardiac myocytes.
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Affiliation(s)
- Emily K Pugach
- University of Colorado at Boulder, Department of Molecular, Cellular, and Developmental Biology, BioFrontiers Institute, Boulder, CO 80303 USA
| | - Christa L Blenck
- University of Colorado at Boulder, Department of Molecular, Cellular, and Developmental Biology, BioFrontiers Institute, Boulder, CO 80303 USA
| | - Joseph M Dragavon
- University of Colorado, BioFrontiers Advanced Light Microscopy Core, BioFrontiers Institute, Boulder, CO 80309 USA
| | - Stephen J Langer
- University of Colorado at Boulder, Department of Molecular, Cellular, and Developmental Biology, BioFrontiers Institute, Boulder, CO 80303 USA
| | - Leslie A Leinwand
- University of Colorado at Boulder, Department of Molecular, Cellular, and Developmental Biology, BioFrontiers Institute, Boulder, CO 80303 USA
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Sołtysik K, Czekaj P. ERα36--Another piece of the estrogen puzzle. Eur J Cell Biol 2015; 94:611-25. [PMID: 26522827 DOI: 10.1016/j.ejcb.2015.10.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2015] [Revised: 09/03/2015] [Accepted: 10/09/2015] [Indexed: 12/22/2022] Open
Abstract
Although the nuclear action of estrogen receptors (ER) is a well-known fact, evidence supporting membrane estrogen receptors is steadily accumulating. New ER variants of unrecognized function have been discovered. ERα is a product of the ESR1 gene. It serves not only as a template for the full-length 66kDa protein, but also for smaller isoforms which exist as independent receptors. The recently discovered ERα36 (36kDa), consisting of 310 amino acids of total 595 ERα66 protein residues, is an example of that group. The transcription initiation site is identified in the first intron of the ESR1 gene. C-Terminal 27 amino acids are encoded by previously unknown exon 9. The presence of this unique C-terminal sequence creates an opportunity for the production of selective antibodies. ERα36 has been shown to have a high affinity to the cell membrane and as much as 90% of the protein can be bound with it. Post-translational palmitoylation is suspected to play a crucial role in ERα36 anchoring to the cell membrane. In silico analysis suggests the existence of a potential transmembrane domain in ERα36. ERα36 was found in most cells of animals at various ages, but its exact physiological function remains to be fully elucidated. It seems that cells traditionally considered as being deprived of ER are able to respond to hormonal stimulation via the ERα36 receptor. Moreover, ERα36 displays unique pharmacological properties and its action may be behind antiestrogen resistance. The use of ERα36 in cancer diagnosis gives rise to great expectations.
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Affiliation(s)
- Kamil Sołtysik
- Students Scientific Society, School of Medicine in Katowice, Medical University of Silesia, Katowice, Poland
| | - Piotr Czekaj
- Department of Cytophysiology, Chair of Histology and Embryology, School of Medicine in Katowice, Medical University of Silesia, Katowice, Poland.
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11
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Tamoxifen resistance: From cell culture experiments towards novel biomarkers. Pathol Res Pract 2015; 211:189-97. [DOI: 10.1016/j.prp.2015.01.004] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Revised: 01/12/2015] [Accepted: 01/13/2015] [Indexed: 12/21/2022]
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12
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The temporal expression of estrogen receptor alpha-36 and runx2 in human bone marrow derived stromal cells during osteogenesis. Biochem Biophys Res Commun 2014; 453:552-6. [PMID: 25281901 DOI: 10.1016/j.bbrc.2014.09.111] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Accepted: 09/26/2014] [Indexed: 01/30/2023]
Abstract
During bone maintenance in vivo, estrogen signals through estrogen receptor (ER)-α. The objectives of this study were to investigate the temporal expression of ERα36 and ascertain its functional relevance during osteogenesis in human bone marrow derived stromal cells (BMSC). This was assessed in relation to runt-related transcription factor-2 (runx2), a main modulatory protein involved in bone formation. ERα36 and runx2 subcellular localisation was assessed using immunocytochemistry, and their mRNA expression levels by real time PCR throughout the process of osteogenesis. The osteogenically induced BMSCs demonstrated a rise in ERα36 mRNA during proliferation followed by a decline in expression at day 10, which represents a change in dynamics within the culture between the proliferative stage and the differentiative stage. The mRNA expression profile of runx2 mirrored that of ERα36 and showed a degree subcellular co-localisation with ERα36. This study suggests that ERα36 is involved in the process of osteogenesis in BMSCs, which has implications in estrogen deficient environments.
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Su X, Xu X, Li G, Lin B, Cao J, Teng L. ER-α36: a novel biomarker and potential therapeutic target in breast cancer. Onco Targets Ther 2014; 7:1525-33. [PMID: 25210466 PMCID: PMC4155893 DOI: 10.2147/ott.s65345] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Estrogen receptor-alpha36 (ER-α36) is a 36-kDa variant of estrogen receptor-alpha (ER-α) firstly identified and cloned by Wang et al in 2005. It lacks both transactivation domains (activation function 1 and activation function 2) and has different biological characteristics compared to traditional ER-α (ER-α66). ER-α36 primarily locates on plasma membrane and cytoplasm and functions as a mediator in the rapid membrane-initiated non-genomic signaling pathway. Additionally, it inhibits the traditional genomic signaling pathway mediated by ER-α66 in a dominant-negative pattern. Accumulating evidence has demonstrated that ER-α36 regulates the physiological function of various tissues. Thus, dysregulation of ER-α36 is closely associated with plenty of diseases including cancers. ER-α36 is recognized as a molecular abnormality which solidly correlates to carcinogenesis, aggressiveness, and therapeutic response of breast cancer. Additionally, special attention has been paid to the role of ER-α36 in endocrine therapy resistance. Therefore, ER-α36 provides a novel biomarker of great value for diagnosis, prognosis, and treatment of breast cancer. It may also be a potential therapeutic target for breast cancer patients, especially for those who are resistant to endocrine therapy. In this review, we will overview and update the biological characteristics, underlying mechanism, and function of ER-α36, focusing on its biological function in breast cancer and endocrine therapy resistance. We will evaluate its application value in clinical practice.
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Affiliation(s)
- Xingyun Su
- Department of Surgical Oncology, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China
| | - Xin Xu
- Department of Surgical Oncology, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China
| | - Guangliang Li
- Department of Surgical Oncology, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China ; Department of Medical Oncology, Zhejiang Cancer Hospital, Hangzhou, Zhejiang Province, People's Republic of China
| | - Bingyi Lin
- Key Laboratory of Combined Multi-Organ Transplantation, Ministry of Public Health, Hangzhou, Zhejiang, People's Republic of China
| | - Jiang Cao
- Clinical Research Center, The 2nd Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China
| | - Lisong Teng
- Department of Surgical Oncology, First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, People's Republic of China
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Li L, Wang Q, Lv X, Sha L, Qin H, Wang L, Li L. Expression and Localization of Estrogen Receptor in Human Breast Cancer and Its Clinical Significance. Cell Biochem Biophys 2014; 71:63-8. [DOI: 10.1007/s12013-014-0163-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Yu L, Ke W, Wang Y, Ding W, Wang B, Huang S, Chen J, Wang X, Wang Z, Shen P. Predictive and prognostic value of ER-α36 expression in breast cancer patients treated with chemotherapy. Steroids 2014; 84:11-6. [PMID: 24632025 DOI: 10.1016/j.steroids.2014.03.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Revised: 02/07/2014] [Accepted: 03/01/2014] [Indexed: 10/25/2022]
Abstract
BACKGROUND This study is to investigate the predictive and prognostic value of ER-α36 expression in breast cancer patients treated with chemotherapy. METHODS ER-α36 expression in 120 breast cancer tumors was assessed by an immunohistochemistry assay. All patients were divided into two groups according to the chemotherapy procedure: group A, 50 patients who underwent neoadjuvant chemotherapy before surgery; group B, 70 patients who were performed adjuvant chemotherapy after surgery, and they all took at least two cycles of anthracycline-based and/or paclitaxel-based chemotherapy after surgery. The therapy effect on group A patients was evaluated two cycles later by Response Evaluation Criteria in Solid Tumors version 1.0 (RECIST 1.0). RESULTS ER-α36 protein was positively expressed in 51 tumor specimens (42.5%) and no correlation was found between the expression of ER-α 36 and the expression of the full-length ER-α (ER-α66), progesterone receptor (PgR), human epidermal growth factor receptor 2 (HER-2), Ki-67, tumor sizes, and the numbers of lymph node metastasis. Patients with ER-α36 negative expression tumors treated with the neoadjuvant chemotherapy had a higher remission rate [partial response: stable: progressed (n) 25:3:1 vs.11:9:1; P=0.009], a better response (86% vs. 52%; P=0.009), and a more favorable outcomes in triple-negative breast cancer patients compared to ER-α36 positive patients and ER-α36 negative expression was correlated with DFS in patients treated with neoadjuvant chemotherapy. CONCLUSIONS ER-α36 negative tumors benefit more from neoadjuvant chemotherapy and have better prognosis, which may warrant further studies with larger size of the sample.
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Affiliation(s)
- Lanfang Yu
- Department of Medical Oncology, The First Affiliated Hospital of College of Medicine, Zhejiang University, Hangzhou 310003, PR China
| | - Wei Ke
- Department of Medical Oncology, The First Affiliated Hospital of College of Medicine, Zhejiang University, Hangzhou 310003, PR China
| | - Yanli Wang
- Department of Pathology, The First Affiliated Hospital of College of Medicine, Zhejiang University, Hangzhou 310003, PR China
| | - Wei Ding
- Department of Pathology, The First Affiliated Hospital of College of Medicine, Zhejiang University, Hangzhou 310003, PR China
| | - Bo Wang
- Department of Pathology, The First Affiliated Hospital of College of Medicine, Zhejiang University, Hangzhou 310003, PR China
| | - Sui Huang
- Department of Medical Oncology, The First Affiliated Hospital of College of Medicine, Zhejiang University, Hangzhou 310003, PR China
| | - Jing Chen
- Department of Medical Oncology, The First Affiliated Hospital of College of Medicine, Zhejiang University, Hangzhou 310003, PR China
| | - Xiaoting Wang
- Department of Medical Oncology, The First Affiliated Hospital of College of Medicine, Zhejiang University, Hangzhou 310003, PR China
| | - Zhaoyi Wang
- Department of Medical Microbiology and Immunology, Creighton University, Omaha, NE 68178, USA
| | - Peng Shen
- Department of Medical Oncology, The First Affiliated Hospital of College of Medicine, Zhejiang University, Hangzhou 310003, PR China.
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Gu Y, Chen T, López E, Wu W, Wang X, Cao J, Teng L. The therapeutic target of estrogen receptor-alpha36 in estrogen-dependent tumors. J Transl Med 2014; 12:16. [PMID: 24447535 PMCID: PMC3899443 DOI: 10.1186/1479-5876-12-16] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2013] [Accepted: 01/18/2014] [Indexed: 12/24/2022] Open
Abstract
Estrogen receptor-alpha36 (ER-α36) is a new isoform of estrogen receptors without transcriptional activation domains of the classical ER-α(ER - α66). ER-α36 is mainly located in cytoplasm and plasma membrane. ER-α36 mediates non-genomic signaling and is involved in genomic signaling of other ERs. Recently ER-α36 is found to play a critical role in the development of estrogen-dependent cancers and endocrine resistance of breast cancer. The present article overviews and updates the biological nature and function of ER-α36, potential interaction of ER-α36 with other estrogen receptors and growth factor receptors, intracellular signaling pathways, potential mechanism by which ER-α36 may play an important role in the development of tumor resistance to endocrine therapies.
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Affiliation(s)
| | | | | | | | - Xiangdong Wang
- Department of Surgical Oncology, The 1st Affiliated Hospital, School of Medicine, Zhejiang University, 79, Qingchun Road, Hangzhou 310003 Zhejiang Province, China.
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Sun L, Wang J, Zhang L, Li X, Shen D. Expression of ER-a36, a Novel Variant of Estrogen Receptor in Endometrial Carcinoma and Its Clinical Significance. Gynecol Obstet Invest 2013; 75:68-72. [DOI: 10.1159/000339933] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2011] [Accepted: 06/03/2012] [Indexed: 01/16/2023]
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Rao J, Jiang X, Wang Y, Chen B. Advances in the understanding of the structure and function of ER-α36,a novel variant of human estrogen receptor-alpha. J Steroid Biochem Mol Biol 2011; 127:231-7. [PMID: 21888973 DOI: 10.1016/j.jsbmb.2011.08.004] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2011] [Revised: 08/01/2011] [Accepted: 08/04/2011] [Indexed: 11/25/2022]
Abstract
Estrogen receptors (ERs) belong to the nuclear receptor superfamily, whose members include ER-α66, ER-α36, ER-α46 and ER-β. Each receptor performs specific functions through binding with a specific ligand, such as estrogen. Recently, ER-α36, a novel variant of human estrogen receptor-alpha (ER-α), was identified and cloned. ER-α36 inhibits, in a dominant-negative manner, the transactivation of both the wild-type ER-α (ER-α66) and ER-β. As a predominantly membrane-based ER, ER-α36 mediates nongenomic estrogen signaling and is involved in the resistance of breast cancer to endocrine therapy, i.e., tamoxifen. This review summarizes recent studies on the structure and function of ER-α36 and the relationship of ER-α36 with cancer, with special emphasis on its function in the resistance of breast cancer to endocrine therapy.
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Affiliation(s)
- Jun Rao
- Department of Biochemistry and Molecular Biology, Third Military Medical University, Chongqing 400038, China
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