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Pinto PIS, Andrade AR, Moreira C, Zapater C, Thorne MAS, Santos S, Estêvão MD, Gomez A, Canario AVM, Power DM. Genistein and estradiol have common and specific impacts on the sea bass (Dicentrarchus labrax) skin-scale barrier. J Steroid Biochem Mol Biol 2019; 195:105448. [PMID: 31421232 DOI: 10.1016/j.jsbmb.2019.105448] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Revised: 08/05/2019] [Accepted: 08/13/2019] [Indexed: 10/26/2022]
Abstract
Teleost fish scales play important roles in animal protection and homeostasis. They can be targeted by endogenous estrogens and by environmental estrogenic endocrine disruptors. The phytoestrogen genistein is ubiquitous in the environment and in aquaculture feeds and is a disruptor of estrogenic processes in vertebrates. To test genistein disrupting actions in teleost fish we used a minimally invasive approach by analysing scales plucked from the skin of sea bass (Dicentrarchus labrax). Genistein transactivated all three fish nuclear estrogen receptors and was most potent with the Esr2, had the highest efficacy with Esr1, but reached, in all cases, transactivation levels lower than those of estradiol. RNA-seq revealed 254 responsive genes in the sea bass scales transcriptome with an FDR < 0.05 and more than 2-fold change in expression, 1 or 5 days after acute exposure to estradiol or to genistein. 65 genes were specifically responsive to estradiol and 106 by genistein while 83 genes were responsive to both compounds. Estradiol specifically regulated genes of protein/matrix turnover and genistein affected sterol biosynthesis and regeneration, while innate immune responses were affected by both compounds. This comprehensive study revealed the impact on the fish scale transcriptome of estradiol and genistein, providing a solid background to further develop fish scales as a practical screening tool for endocrine disrupting chemicals in teleosts.
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Affiliation(s)
- Patricia I S Pinto
- CCMAR - Centro de Ciencias do Mar (CCMAR), Universidade do Algarve, Campus de Gambelas, Edifício 7, 8005-139 Faro, Portugal.
| | - André R Andrade
- CCMAR - Centro de Ciencias do Mar (CCMAR), Universidade do Algarve, Campus de Gambelas, Edifício 7, 8005-139 Faro, Portugal.
| | - Catarina Moreira
- Normandy University, FR CNRS 3730 SCALE, UMR-I 02 INERIS-URCA-ULH Environmental Stress and Aquatic Biomonitoring (SEBIO), Université Le Havre Normandie, F-76600 Le Havre, France.
| | - Cinta Zapater
- IATS - Instituto de Acuicultura Torre la Sal, Ribera de Cabanes, 12595 Castellón, Spain.
| | - Michael A S Thorne
- British Antarctic Survey (BAS), High Cross, Madingley Road, Cambridge, CB3 0ET, UK.
| | - Soraia Santos
- CCMAR - Centro de Ciencias do Mar (CCMAR), Universidade do Algarve, Campus de Gambelas, Edifício 7, 8005-139 Faro, Portugal.
| | - M Dulce Estêvão
- CCMAR - Centro de Ciencias do Mar (CCMAR), Universidade do Algarve, Campus de Gambelas, Edifício 7, 8005-139 Faro, Portugal; Escola Superior de Saúde, Universidade do Algarve, Campus de Gambelas, Edifício 1, 8005-139 Faro, Portugal.
| | - Ana Gomez
- IATS - Instituto de Acuicultura Torre la Sal, Ribera de Cabanes, 12595 Castellón, Spain.
| | - Adelino V M Canario
- CCMAR - Centro de Ciencias do Mar (CCMAR), Universidade do Algarve, Campus de Gambelas, Edifício 7, 8005-139 Faro, Portugal.
| | - Deborah M Power
- CCMAR - Centro de Ciencias do Mar (CCMAR), Universidade do Algarve, Campus de Gambelas, Edifício 7, 8005-139 Faro, Portugal.
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2
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Wagner L, Howe K, Philbrick KA, Maddalozzo GF, Kuah AF, Wong CP, Olson DA, Branscum AJ, Iwaniec UT, Turner RT. Effects of Alcohol and Estrogen Receptor Blockade Using ICI 182,780 on Bone in Ovariectomized Rats. Alcohol Clin Exp Res 2019; 43:2301-2311. [PMID: 31479513 DOI: 10.1111/acer.14185] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Accepted: 08/22/2019] [Indexed: 11/28/2022]
Abstract
BACKGROUND Estrogen signaling is essential for the sexual dimorphism of the skeleton, is required for normal bone remodeling balance in adults, and may influence the skeletal response to alcohol. High levels of alcohol consumption lower bone mass in ovary-intact but not ovariectomized (ovx) rats. However, the extremely rapid rate of bone loss immediately following ovx may obscure the effects of alcohol. We therefore determined (i) whether heavy alcohol consumption (35% caloric intake) influences bone in sexually mature ovx rats with established cancellous osteopenia and (ii) whether ICI 182,780 (ICI), a potent estrogen receptor signaling antagonist, alters the skeletal response to alcohol. METHODS Three weeks following ovx, rats were randomized into 5 groups, (i) baseline, (ii) control + vehicle, (iii) control + ICI, (iv) ethanol (EtOH) + vehicle, or (v) EtOH + ICI, and treated accordingly for 4 weeks. Dual-energy X-ray absorptiometry, microcomputed tomography, blood measurements of markers of bone turnover, and gene expression in femur and uterus were used to evaluate response to alcohol and ICI. RESULTS Rats consuming alcohol had lower bone mass and increased fat mass. Bone microarchitecture of the tibia and gene expression in femur were altered; specifically, there was reduced accrual of cortical bone, net loss of cancellous bone, and differential expression of 19/84 genes related to bone turnover. Furthermore, osteocalcin, a marker of bone turnover, was lower in alcohol-fed rats. ICI had no effect on weight gain, body composition, or cortical bone. ICI reduced cancellous bone loss and serum CTX-1, a biochemical marker of bone resorption; alcohol antagonized the latter 2 responses. Neither alcohol nor ICI affected uterine weight or gene expression. CONCLUSIONS Alcohol exaggerated bone loss in ovx rats in the presence or absence of estrogen receptor blockade with ICI. The negligible effect of alcohol on uterus and limited effects of ICI on bone in alcohol-fed ovx rats suggest that estrogen receptor signaling plays a limited role in the action of alcohol on bone in a rat model for chronic alcohol abuse.
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Affiliation(s)
- Lindsay Wagner
- Skeletal Biology Laboratory, School of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon
| | - Kathy Howe
- Skeletal Biology Laboratory, School of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon
| | - Kenneth A Philbrick
- Skeletal Biology Laboratory, School of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon
| | - Gianni F Maddalozzo
- Skeletal Biology Laboratory, School of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon
| | - Amida F Kuah
- Skeletal Biology Laboratory, School of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon
| | - Carmen P Wong
- Skeletal Biology Laboratory, School of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon
| | - Dawn A Olson
- Skeletal Biology Laboratory, School of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon
| | - Adam J Branscum
- Biostatistics Program, School of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon
| | - Urszula T Iwaniec
- Skeletal Biology Laboratory, School of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon.,Center for Healthy Aging Research, Oregon State University, Corvallis, Oregon
| | - Russell T Turner
- Skeletal Biology Laboratory, School of Biological and Population Health Sciences, Oregon State University, Corvallis, Oregon.,Center for Healthy Aging Research, Oregon State University, Corvallis, Oregon
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Zuo D, Shogren KL, Zang J, Jewison DE, Waletzki BE, Miller AL, Okuno SH, Cai Z, Yaszemski MJ, Maran A. Inhibition of STAT3 blocks protein synthesis and tumor metastasis in osteosarcoma cells. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2018; 37:244. [PMID: 30286779 PMCID: PMC6172747 DOI: 10.1186/s13046-018-0914-0] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/10/2018] [Accepted: 09/20/2018] [Indexed: 02/07/2023]
Abstract
BACKGROUND Osteosarcoma is the most common bone cancer. Despite advances, molecular mechanisms associated with osteosarcoma have not been fully understood. Hence, an effective treatment for osteosarcoma has yet to be developed. Even though signal transducer and activator of transcription3 (STAT3) has been implicated, its role in pathogenesis of osteosarcoma is not fully determined. In this study, we investigated the antitumor effect of napabucasin (NP) (BBI608), an inhibitor of STAT3 on osteosarcoma in vitro and in vivo and studied the underlying molecular mechanism. METHODS Cell viability, colony formation, apoptosis, tumor growth and metastasis assays were performed to examine the effect of NP on osteosarcoma in vitro and in vivo. Real-time RT-PCR, western analysis, immunofluorescence and reporter assays were used to monitor the expression and activity of proteins and underlying molecular pathways. Protein synthesis, co-immunoprecipitation and CAP binding assays were carried out to understand NP-mediated mechanism of actions in osteosarcoma cells. RESULTS Our results show that NP treatment decreases cell viability and induces apoptosis in several osteosarcoma cell lines. NP treatment suppresses both expression and phosphorylation of STAT3 in addition to blocking STAT3-mediated transcription and downstream target proteins in osteosarcoma cells. Furthermore, NP inhibits protein synthesis through regulation of the eukaryotic initiation factor 4E (eIF4E) and eIF4E-binding protein 1 (4E-BP1). NP also inhibits the progression of osteosarcoma tumors and metastasis in vivo in an orthotopic tibial model of osteosarcoma. CONCLUSIONS Taken together, our investigation reveals that NP acts through a novel mechanism and inhibits osteosarcoma growth and metastasis, and could be investigated clinically for treating osteosarcoma patients alone or in combination with other drugs.
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Affiliation(s)
- Dongqing Zuo
- Department of Orthopedic Surgery, 2-69 Medical Sciences, Mayo Clinic, 200 First St SW, Rochester, MN, 55905, USA.,Department of Orthopedics, Shanghai General Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Kristen L Shogren
- Department of Orthopedic Surgery, 2-69 Medical Sciences, Mayo Clinic, 200 First St SW, Rochester, MN, 55905, USA
| | - Jie Zang
- Musculoskeletal Tumor Center, People's Hospital, Peking University, Beijing, 100044, China
| | - Donna E Jewison
- Department of Orthopedic Surgery, 2-69 Medical Sciences, Mayo Clinic, 200 First St SW, Rochester, MN, 55905, USA
| | - Brian E Waletzki
- Department of Orthopedic Surgery, 2-69 Medical Sciences, Mayo Clinic, 200 First St SW, Rochester, MN, 55905, USA
| | | | - Scott H Okuno
- Division of Medical Oncology, Mayo Clinic, Rochester, MN, USA
| | - Zhengdong Cai
- Department of Orthopedics, Shanghai General Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Michael J Yaszemski
- Department of Orthopedic Surgery, 2-69 Medical Sciences, Mayo Clinic, 200 First St SW, Rochester, MN, 55905, USA
| | - Avudaiappan Maran
- Department of Orthopedic Surgery, 2-69 Medical Sciences, Mayo Clinic, 200 First St SW, Rochester, MN, 55905, USA.
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Gujam FJA, McMillan DC, Edwards J. The relationship between total and phosphorylated STAT1 and STAT3 tumour cell expression, components of tumour microenvironment and survival in patients with invasive ductal breast cancer. Oncotarget 2018; 7:77607-77621. [PMID: 27769057 PMCID: PMC5363608 DOI: 10.18632/oncotarget.12730] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 10/03/2016] [Indexed: 12/31/2022] Open
Abstract
The aim of the present study was to examine the relationship between tumour cell expression of total and phosphorylated STAT1 (ph-STAT1) and STAT3 (ph-STAT-3), components of tumour microenvironment and survival in patients with invasive ductal breast cancer. Immunohistochemical analysis of total and ph-STAT1, and STAT3 were performed on tissue microarray of 384 breast cancer specimens. Tumour cell expression of STAT1 and STAT3 at both cytoplasmic and nuclear locations were combined and identified as STAT1/STAT3 tumour cell expression. These results were related to cancer specific survival (CSS) and phenotypic features of the tumour and the host. High ph-STAT1 and ph-STAT3 tumour cell expression were associated with increased ER (both P≤0.001) and PR (both P <0.05), reduced tumour grade (P=0.015 and P<0.001 respectively) and necrosis (both P=0.001). Ph-STAT1 was associated with increased general inflammatory infiltrate (P=0.007) and ph-STAT3 was associated with lower CD4+ infiltration (P=0.024). In multivariate survival analysis, only high ph-STAT3 tumour cell expression was a predictor of improved CSS (P=0.010) independent of other tumour and host-based factors. STAT1 and STAT3 tumour cell expression appeared to be an important determinant of favourable outcome in patients with invasive ductal breast cancer. The present results suggest that STAT1 and STAT3 may affect disease outcome through direct impact on tumour cells, counteracting aggressive tumour features, as well as interaction with the surrounding microenvironment.
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Affiliation(s)
- Fadia J A Gujam
- Academic Unit of Surgery, College of Medical, Veterinary and Life Sciences-University of Glasgow, Royal Infirmary, Glasgow, Scotland.,Unit of Experimental Therapeutics, Institute of Cancer, College of Medical, Veterinary and Life Sciences-University of Glasgow, Wolfson Wohl Cancer Research Centre, Glasgow, Scotland
| | - Donald C McMillan
- Academic Unit of Surgery, College of Medical, Veterinary and Life Sciences-University of Glasgow, Royal Infirmary, Glasgow, Scotland
| | - Joanne Edwards
- Unit of Experimental Therapeutics, Institute of Cancer, College of Medical, Veterinary and Life Sciences-University of Glasgow, Wolfson Wohl Cancer Research Centre, Glasgow, Scotland
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Bravo D, Shogren KL, Zuo D, Wagner ER, Sarkar G, Yaszemski MJ, Maran A. 2-Methoxyestradiol-Mediated Induction of Frzb Contributes to Cell Death and Autophagy in MG63 Osteosarcoma Cells. J Cell Biochem 2017; 118:1497-1504. [PMID: 27883247 DOI: 10.1002/jcb.25809] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Accepted: 11/22/2016] [Indexed: 12/31/2022]
Abstract
Osteosarcoma is a bone tumor that mainly affects children and adolescents. Although its pathogenesis is still not fully understood, activation of Wnt signaling has been implicated in the development and metastasis of osteosarcoma. In this report, we have investigated the effect of the anti-tumor compound, 2-methoxyestradiol (2-ME) on Wnt antagonist frizzled-related protein b (Frzb), also known as secreted frizzled-related protein (sFRP)3 in human osteosarcoma (MG63) cells. Our results show that 2-ME treatment induces Frzb gene promoter activity, and increases Frzb mRNA and protein levels in osteosarcoma cells. In addition, 2-ME treatment regulates downstream Wnt signaling, increasing the cytoplasmic levels of β-catenin, and blocking β-catenin-mediated Wnt activation in osteosarcoma cells. 2-ME-mediated induction of Frzb protein expression is specific to osteosarcoma cells, as it does not affect Frzb expression in normal primary human osteoblasts. Furthermore, 2-ME-induced apoptosis and autophagy are blocked in osteosarcoma cells transfected with Frzb siRNAs. Taken together, these studies demonstrate that Frzb protein plays an important role in 2-ME-mediated anti-tumor mechanisms in osteosarcoma cells. J. Cell. Biochem. 118: 1497-1504, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Dalibel Bravo
- Department of Orthopedic surgery, Mayo Clinic, Rochester, Minnesota
| | | | - Dongqing Zuo
- Department of Orthopedic surgery, Mayo Clinic, Rochester, Minnesota
| | - Eric R Wagner
- Department of Orthopedic surgery, Mayo Clinic, Rochester, Minnesota
| | - Gobinda Sarkar
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota
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6
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The estrogen metabolite 2-methoxyestradiol regulates eukaryotic initiation factor 4E (eIF4E) and inhibits protein synthesis in MG63 osteosarcoma cells. Genes Dis 2016; 3:153-158. [PMID: 30258883 PMCID: PMC6147162 DOI: 10.1016/j.gendis.2016.04.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Accepted: 04/10/2016] [Indexed: 12/23/2022] Open
Abstract
Osteosarcoma is a primary bone tumor that affects children and young adults. The estrogen metabolite 2-methoxyestradiol (2-ME) induces cell death in osteosarcoma cells. To determine whether 2-ME actions involve the control of protein synthesis, we studied the effect of 2-ME on eukaryotic initiation factor 4E (eIF4E) and eIF4E-binding protein 1 (4E-BP1) in MG63 osteosarcoma cells. Our results show that 2-ME treatment increases the association of eIF4E with 4E-BP1 in osteosarcoma cells. Also, 2-ME decreases the binding of eIF4E protein to 7-methyl-guanosine cap structure, indicating that 2-ME treatment results in the inhibition of translational initiation. These findings are further supported by the inhibition of protein synthesis in 2-ME-treated osteosarcoma cells. Taken together, our studies show that 2-ME-mediated antitumor effects in osteosarcoma cells involve the regulation of protein synthesis, and translational machinery could serve as a target in the treatment of osteosarcoma.
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7
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Activation of ERα signaling differentially modulates IFN-γ induced HLA-class II expression in breast cancer cells. PLoS One 2014; 9:e87377. [PMID: 24475282 PMCID: PMC3903652 DOI: 10.1371/journal.pone.0087377] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2013] [Accepted: 12/23/2013] [Indexed: 11/24/2022] Open
Abstract
The coordinate regulation of HLA class II (HLA-II) is controlled by the class II transactivator, CIITA, and is crucial for the development of anti-tumor immunity. HLA-II in breast carcinoma is associated with increased IFN-γ levels, reduced expression of the estrogen receptor (ER) and reduced age at diagnosis. Here, we tested the hypothesis that estradiol (E2) and ERα signaling contribute to the regulation of IFN-γ inducible HLA-II in breast cancer cells. Using a panel of established ER− and ER+ breast cancer cell lines, we showed that E2 attenuated HLA-DR in two ER+ lines (MCF-7 and BT-474), but not in T47D, while it augmented expression in ER− lines, SK-BR-3 and MDA-MB-231. To further study the mechanism(s), we used paired transfectants: ERα+ MC2 (MDA-MB-231 c10A transfected with the wild type ERα gene) and ERα− VC5 (MDA-MB-231 c10A transfected with the empty vector), treated or not with E2 and IFN-γ. HLA-II and CIITA were severely reduced in MC2 compared to VC5 and were further exacerbated by E2 treatment. Reduced expression occurred at the level of the IFN-γ inducible CIITA promoter IV. The anti-estrogen ICI 182,780 and gene silencing with ESR1 siRNA reversed the E2 inhibitory effects, signifying an antagonistic role for activated ERα on CIITA pIV activity. Moreover, STAT1 signaling, necessary for CIITA pIV activation, and selected STAT1 regulated genes were variably downregulated by E2 in transfected and endogenous ERα positive breast cancer cells, whereas STAT1 signaling was noticeably augmented in ERα− breast cancer cells. Collectively, these results imply immune escape mechanisms in ERα+ breast cancer may be facilitated through an ERα suppressive mechanism on IFN-γ signaling.
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8
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Yang C, Shogren KL, Goyal R, Bravo D, Yaszemski MJ, Maran A. RNA-dependent protein kinase is essential for 2-methoxyestradiol-induced autophagy in osteosarcoma cells. PLoS One 2013; 8:e59406. [PMID: 23527187 PMCID: PMC3602192 DOI: 10.1371/journal.pone.0059406] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Accepted: 02/16/2013] [Indexed: 11/26/2022] Open
Abstract
Osteosarcoma is the most common primary malignant bone tumor in children and young adults. Surgical resection and adjunctive chemotherapy are the only widely available options of treatment for this disease. Anti-tumor compound 2-Methoxyestradiol (2-ME) triggers cell death through the induction of apoptosis in osteosarcoma cells, but not in normal osteoblasts. In this report, we have investigated whether autophagy plays a role in 2-ME actions on osteosarcoma cells. Transmission electron microscopy imaging shows that 2-ME treatment leads to the accumulation of autophagosomes in human osteosarcoma cells. 2-ME induces the conversion of the microtubule-associated protein LC3-I to LC3-II, a biochemical marker of autophagy that is correlated with the formation of autophagosomes. Conversion to LC3-II is accompanied by protein degradation in 2-ME-treated cells. 2-ME does not induce autophagosome formation in normal primary human osteoblasts. In addition, 2-ME-dependent autophagosome formation in osteosarcoma cells requires ATG7 expression. Furthermore, 2-ME does not induce accumulation of autophagosomes in osteosarcoma cells that express dominant negative mutant RNA-dependent protein kinase (PKR) and are resistant to anti-proliferative and anti-tumor effects of 2-ME. Taken together, our study shows that 2-ME treatment induces PKR-dependent autophagy in osteosarcoma cells, and that autophagy could play an important role in 2-ME-mediated anti-tumor actions and in the control of osteosarcoma.
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Affiliation(s)
- Caihong Yang
- Department of Orthopedics, Mayo Clinic, Rochester, Minnesota, United States of America
- Department of Orthopedic, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Kristen L. Shogren
- Department of Orthopedics, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Ribu Goyal
- Department of Orthopedics, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Dalibel Bravo
- Department of Orthopedics, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Michael J. Yaszemski
- Department of Orthopedics, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Avudaiappan Maran
- Department of Orthopedics, Mayo Clinic, Rochester, Minnesota, United States of America
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9
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Magkou C, Giannopoulou I, Theohari I, Fytou A, Rafailidis P, Nomikos A, Papadimitriou C, Nakopoulou L. Prognostic significance of phosphorylated STAT-1 expression in premenopausal and postmenopausal patients with invasive breast cancer. Histopathology 2012; 60:1125-32. [DOI: 10.1111/j.1365-2559.2011.04143.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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10
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Knoblach T, Grandel B, Seiler J, Nevels M, Paulus C. Human cytomegalovirus IE1 protein elicits a type II interferon-like host cell response that depends on activated STAT1 but not interferon-γ. PLoS Pathog 2011; 7:e1002016. [PMID: 21533215 PMCID: PMC3077363 DOI: 10.1371/journal.ppat.1002016] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2010] [Accepted: 02/02/2011] [Indexed: 12/12/2022] Open
Abstract
Human cytomegalovirus (hCMV) is a highly prevalent pathogen that, upon primary infection, establishes life-long persistence in all infected individuals. Acute hCMV infections cause a variety of diseases in humans with developmental or acquired immune deficits. In addition, persistent hCMV infection may contribute to various chronic disease conditions even in immunologically normal people. The pathogenesis of hCMV disease has been frequently linked to inflammatory host immune responses triggered by virus-infected cells. Moreover, hCMV infection activates numerous host genes many of which encode pro-inflammatory proteins. However, little is known about the relative contributions of individual viral gene products to these changes in cellular transcription. We systematically analyzed the effects of the hCMV 72-kDa immediate-early 1 (IE1) protein, a major transcriptional activator and antagonist of type I interferon (IFN) signaling, on the human transcriptome. Following expression under conditions closely mimicking the situation during productive infection, IE1 elicits a global type II IFN-like host cell response. This response is dominated by the selective up-regulation of immune stimulatory genes normally controlled by IFN-γ and includes the synthesis and secretion of pro-inflammatory chemokines. IE1-mediated induction of IFN-stimulated genes strictly depends on tyrosine-phosphorylated signal transducer and activator of transcription 1 (STAT1) and correlates with the nuclear accumulation and sequence-specific binding of STAT1 to IFN-γ-responsive promoters. However, neither synthesis nor secretion of IFN-γ or other IFNs seems to be required for the IE1-dependent effects on cellular gene expression. Our results demonstrate that a single hCMV protein can trigger a pro-inflammatory host transcriptional response via an unexpected STAT1-dependent but IFN-independent mechanism and identify IE1 as a candidate determinant of hCMV pathogenicity.
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Affiliation(s)
- Theresa Knoblach
- Institute for Medical Microbiology and Hygiene, University of Regensburg,
Regensburg, Germany
| | - Benedikt Grandel
- Institute for Medical Microbiology and Hygiene, University of Regensburg,
Regensburg, Germany
| | - Jana Seiler
- Institute for Medical Microbiology and Hygiene, University of Regensburg,
Regensburg, Germany
| | - Michael Nevels
- Institute for Medical Microbiology and Hygiene, University of Regensburg,
Regensburg, Germany
| | - Christina Paulus
- Institute for Medical Microbiology and Hygiene, University of Regensburg,
Regensburg, Germany
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11
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Dadsetan M, Szatkowski JP, Shogren KL, Yaszemski MJ, Maran A. Hydrogel-mediated DNA delivery confers estrogenic response in nonresponsive osteoblast cells. J Biomed Mater Res A 2010; 91:1170-7. [PMID: 19148929 DOI: 10.1002/jbm.a.32291] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Oligo(polyethylene glycol) fumarate (OPF) hydrogel has been employed in musculoskeletal tissue engineering for photoencapsulation of chondrocytes and as a matrix for marrow stromal cells differentiation. In this study, we have studied the application of OPF hydrogel for coencapsulation of DNA and bone cells and examined whether coencapsulation can enhance gene transfer by maintaining the DNA within the cellular microenvironment. Our results showed that plasmid DNA encoding green fluorescence protein (GFP), coencapsulated with bone tumor cells, was capable of transfecting the cells, and the transfected tumor cells continuously expressed GFP protein over the time course of study (21 days). Furthermore, we have examined the coencapsulation of estrogen receptor (ER) encoding plasmid DNA and human fetal osteoblast cells (hFOB) that lack endogenous ER. Our results show that the transfected cells responded to estrogen as alkaline phosphatase (ALP), and estrogen response element (ERE)-directed luciferase enzyme activities increased with estrogen treatment. Taken together, these studies show that OPF hydrogel could be further explored for targeted gene delivery in bone and other tissues encapsulated within the hydrogels.
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Affiliation(s)
- M Dadsetan
- Department of Orthopedics, Mayo Clinic College of Medicine, Rochester, Minnesota 55905, USA
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12
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Krämer OH, Heinzel T. Phosphorylation-acetylation switch in the regulation of STAT1 signaling. Mol Cell Endocrinol 2010; 315:40-8. [PMID: 19879327 DOI: 10.1016/j.mce.2009.10.007] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2009] [Revised: 10/13/2009] [Accepted: 10/19/2009] [Indexed: 02/07/2023]
Abstract
STAT1 signaling regulates the expression of important genes controlling cell growth, differentiation, apoptosis, and immune functions. Biochemical and genetic experiments have identified how this cascade is modulated. Phosphorylation of STAT1 tyrosine and serine moieties is induced rapidly by cytokines and growth factors. Upon nuclear translocation, phosphorylated STAT1 homo- and heterodimers activate gene expression. Inactivation of phosphorylated nuclear STAT1 has to be precisely regulated in order to allow signal transduction within limited time frames. Lysine acetylation has recently been appreciated as a novel mechanism regulating signal transduction events relying on STAT proteins. Here, we review these analyses and the finding that a switch from phosphorylated to acetylated STAT1 regulates acetylation-dependent dephosphorylation of STAT1 via the T cell tyrosine phosphatase. We discuss how these observations can be integrated into our current understanding of STAT-dependent cytokine signaling and its potential relevance for endocrine functions.
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Affiliation(s)
- Oliver H Krämer
- Institute of Biochemistry and Biophysics, Center for Molecular Biomedicine (CMB), University of Jena, Hans-Knöll-Str. 2, 07743 Jena, Germany.
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13
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Dziennis S, Alkayed NJ. Role of signal transducer and activator of transcription 3 in neuronal survival and regeneration. Rev Neurosci 2009; 19:341-61. [PMID: 19145989 DOI: 10.1515/revneuro.2008.19.4-5.341] [Citation(s) in RCA: 116] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Signal Transducers and Activators of Transcription (STATs) comprise a family of transcription factors that mediate a wide variety of biological functions in the central and peripheral nervous systems. Injury to neural tissue induces STAT activation, and STATs are increasingly recognized for their role in neuronal survival. In this review, we discuss the role of STAT3 during neural development and following ischemic and traumatic injury in brain, spinal cord and peripheral nerves. We focus on STAT3 because of the expanding body of literature that investigates protective and regenerative effects of growth factors, hormones and cytokines that use STAT3 to mediate their effect, in part through transcriptional upregulation of neuroprotective and neurotrophic genes. Defining the endogenous molecular mechanisms that lead to neuroprotection by STAT3 after injury might identify novel therapeutic targets against acute neural tissue damage as well as chronic neurodegenerative disorders.
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Affiliation(s)
- Suzan Dziennis
- Department of Anesthesiology & Peri-Operative Medicine, Oregon Health & Science University, Portland, OR 97239-3098, USA
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14
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Maran A, Shogren KL, Benedikt M, Sarkar G, Turner RT, Yaszemski MJ. 2-methoxyestradiol-induced cell death in osteosarcoma cells is preceded by cell cycle arrest. J Cell Biochem 2008; 104:1937-45. [PMID: 18384113 DOI: 10.1002/jcb.21758] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
2-Methoxyestradiol (2-ME), a naturally occurring mammalian metabolite of 17beta-Estradiol (E2), induces cell death in osteosarcoma cells. To further understand the molecular mechanisms of action, we have investigated cell cycle progression in 2-ME-treated human osteosarcoma (MG63, SaOS-2 and LM7 [corrected]) cells. At 5 microM, 2-ME induced growth arrest by inducing a block in cell cycle; 2-ME-treatment resulted in 2-fold increases in G1 phase cells and a decrease in S phase cells in MG63 and SaOS-2 osteosarcoma cell lines, compared to the appropriate vehicle controls. 2-ME-treatment induced a threefold increase in the G2 phase in LM7 [corrected] osteosarcoma cells. The results demonstrated steroid specificity, as the tumorigenic metabolite, 16alpha-hydroxyestradiol (16-OHE), did not have any effect on cell cycle progression in osteosarcoma cells. The cell cycle arrest coincided with an increase in expression of the cell cycle markers p21, p27 and p53 proteins in 2-ME-treated osteosarcoma cells. Also, MG63 cells, transiently transfected with cDNA for a 'loss of function mutant' RNA-dependent protein kinase (PKR) protein, were resistant to 2-ME-induced cell cycle arrest. These results suggest that 2-ME works in concert with factors regulating cell cycle progression, and cell cycle arrest precedes cell death in 2-ME-treated osteosarcoma cells.
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Affiliation(s)
- Avudaiappan Maran
- Department of Orthopedics, Mayo Clinic, Rochester, Minnesota 55905, USA.
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15
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Abstract
Anesthesiologists are frequently confronted with patients who are at risk for neurological complications due to perioperative stroke or prior traumatic brain injury. In this review, we address the growing and fascinating body of data that suggests gender and sex steroids influence the pathophysiology of injury and outcome for these patients. Cerebral ischemia, traumatic brain injury, and epilepsy are reviewed in the context of potential sex differences in mechanisms and outcomes of brain injury and the role of estrogen, progesterone, and androgens in shaping these processes. Lastly, implications for current and future perioperative and intensive care are identified.
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Affiliation(s)
- Kamila Vagnerova
- Department of Anesthesiology and Peri-Operative Medicine, Oregon Health and Science University, Portland, Oregon 97239, USA
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16
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Patten RD, Pourati I, Aronovitz MJ, Alsheikh-Ali A, Eder S, Force T, Mendelsohn ME, Karas RH. 17 Beta-estradiol differentially affects left ventricular and cardiomyocyte hypertrophy following myocardial infarction and pressure overload. J Card Fail 2008; 14:245-53. [PMID: 18381189 DOI: 10.1016/j.cardfail.2007.10.024] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2007] [Revised: 09/25/2007] [Accepted: 10/31/2007] [Indexed: 12/01/2022]
Abstract
BACKGROUND We have shown previously that 17beta-estradiol (E2) increases left ventricular (LV) and cardiomyocyte hypertrophy after myocardial infarction (MI). However, E2 decreases hypertrophy in pressure overload models. We hypothesized that the effect of estrogen on cardiac hypertrophy was dependent on the type of hypertrophic stimulus. METHODS AND RESULTS Ovariectomized wild-type female mice (n = 192) were given vehicle or E2 treatment followed by coronary ligation (MI), transverse aortic constriction (TAC), or sham operation. Signaling pathway activation was studied at 3, 24, and 48 hours, whereas echocardiography and hemodynamic studies were performed at 14 days. MI induced early but transient activation of p38 and p42/44 MAPK pathways, whereas TAC induced sustained activation of both pathways. E2 had no effect on these pathways, but increased Stat3 activation after MI while decreasing Stat3 activation after TAC. MI caused LV dilation and decreased fractional shortening (FS) that were unaltered by E2. TAC caused LV dilation, reduced FS, and increased LV mass, but in this model, E2 improved these parameters. After MI, E2 led to increases in myocyte cross-sectional area, atrial natriuretic peptide (ANP) and beta-myosin heavy chain (MHC) gene expression, but E2 diminished TAC-induced increases ANP and beta-MHC gene expression. CONCLUSIONS These data demonstrate that the effects of E2 on LV and myocyte remodeling depend on the nature of the hypertrophic stimulus. The opposing influence of E2 on hypertrophy in these models may, in part, result from differential effects of E2 on Stat3 activation. Further work will be necessary to explore this and other potential mechanisms by which estrogen affects hypertrophy in these models.
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Affiliation(s)
- Richard D Patten
- Molecular Cardiology Research Institute, Tufts-New England Medical Center, Boston, MA 02111, USA
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17
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Denger S, Bähr-Ivacevic T, Brand H, Reid G, Blake J, Seifert M, Lin CY, May K, Benes V, Liu ET, Gannon F. Transcriptome profiling of estrogen-regulated genes in human primary osteoblasts reveals an osteoblast-specific regulation of the insulin-like growth factor binding protein 4 gene. Mol Endocrinol 2007; 22:361-79. [PMID: 17962383 DOI: 10.1210/me.2007-0292] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Estradiol (E2) is believed to modulate physiological functions relevant to osteoblast biology through the actions of estrogen receptors (ERs) that in turn regulate the expression of target genes. The molecular effects of estrogen action in bone remain to be fully elucidated. This study reports a genome-wide molecular and computational analysis of the interaction between ER and regulatory elements on the DNA of target genes in human primary osteoblasts. Of approximately 54,000 gene probes surveyed in this study, a total of 375 genes were up-regulated and 418 genes were down-regulated on exposure to E2, with only 46 of these being direct target genes after 24 h, as determined by concomitant cycloheximide treatment. Computational analysis discovered several pathways where E2 co-regulates multiple functionally linked components. Examination of the genomic sequence of IGF binding protein 4 located ER response elements within the first intron. Using by chromatin immunoprecipitation, we show a site- and cell-specific recruitment of transcription factors to this newly identified regulatory region. Transient transfection studies revealed that this intronic region acts as a functional promoter in human osteoblasts. Taken together, this analysis provides a comprehensive gene transcription profile and identifies several genes of potential physiological importance in controlling estrogen-mediated signaling in primary osteoblasts.
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Affiliation(s)
- Stefanie Denger
- European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany.
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18
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Joyce MM, Burghardt RC, Geisert RD, Burghardt JR, Hooper RN, Ross JW, Ashworth MD, Johnson GA. Pig conceptuses secrete estrogen and interferons to differentially regulate uterine STAT1 in a temporal and cell type-specific manner. Endocrinology 2007; 148:4420-31. [PMID: 17525118 DOI: 10.1210/en.2007-0505] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Conceptus trophectoderm and uterine luminal epithelial cells interact via endocrine, paracrine, and autocrine modulators to mediate pregnancy recognition and implantation. Pig conceptuses not only release estrogens for pregnancy recognition but also secrete interferons during implantation. Because interferon-stimulated genes are increased by interferons secreted for pregnancy recognition in ruminants, we asked whether the interferon-stimulated gene, STAT1, is up-regulated in pig endometrium by conceptus estrogens and/or interferons. STAT1 expression in response to day of pregnancy, estrogen injection, and intrauterine infusion of conceptus secretory proteins in pigs indicated 1) estrogen increases STAT1 in luminal epithelial cells, 2) conceptus secretory proteins that contain interferons increase STAT1 in stroma, 3) STAT1 increases in close proximity to the conceptus, and 4) early estrogen results in conceptus death and no STAT1 in stroma. The interactions of estrogen and interferons to regulate cell-type-specific expression of STAT1 highlight the complex interplay between endometrium and conceptus for pregnancy recognition and implantation.
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Affiliation(s)
- Margaret M Joyce
- Center for Animal Biotechnology and Genomics, Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas 77843, USA
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19
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Tripathi YB, Tripathi P, Korlagunta K, Chai SC, Smith BJ, Arjmandi BH. Role of Sandhika: A Polyherbal Formulation on MC3T3-E1 Osteoblast-like Cells. Inflammation 2007; 31:1-8. [PMID: 17687634 DOI: 10.1007/s10753-007-9044-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Sandhika is a polyherbal formulation, (water soluble fraction of Commiphora mukul, Boswellia serrata, Semecarpus anacardium and Strychnos nux vomica), which has been in clinical use in India for last 20 years. Its modified formulation BHUx has shown specific inhibition of cyclooxygenase (COX)-2 and lipoxygenase (LOX)-15 and has prevented diet-induced atherosclerosis in rabbits. In order to explore the possibility of the use of Sandhika for the management of osteoporosis, we have examined its influence on MC3T3-E1 osteoblast-like cells in presence of lipopolysaccharide (1 microg/ml) in terms of calcium nodule formation and alkaline phosphatase activity. MC3T3-E1 osteoblast-like cells (80% confluence in 6-well plates) were treated with water extract of Sandhika, for 10 days, in the concentration range of 0.5 to 16 mg/ml final concentration, in presence of LPS. Media was changed on every third day and culture supernatant was collected after every change to assess the alkaline phosphatase activity and on the tenth day, cells were washed and stained with "Alizarin S" for visualization of calcium nodules by using Meta Morph software (Universal Imaging, Downingtown, PA). The results showed significant enhancement in calcium nodule formation in the dose dependent manner up to 2 mg/ml, followed by gradual decrease at higher concentrations. This change was accompanied with the increase in the alkaline phosphatase activity in these plates, indicating a potential anabolic effect of this polyherbal formulation on osteoblast-like cells under inflammatory conditions induced by LPS.
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Affiliation(s)
- Yamini B Tripathi
- Department of Medicinal Chemistry, Institute of Medical Sciences, Banaras Hindu University, Varanasi, 221005, India.
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20
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Rajasingh J, Bord E, Qin G, Ii M, Silver M, Hamada H, Ahluwalia D, Goukassian D, Zhu Y, Losordo DW, Kishore R. Enhanced voluntary alcohol consumption after estrogen supplementation negates estrogen-mediated vascular repair in ovariectomized mice. Endocrinology 2007; 148:3618-24. [PMID: 17478555 DOI: 10.1210/en.2006-1357] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Preclinical and observational studies in ovariectomized (OVX) animals and pre- and postmenopausal women, respectively, have suggested the cardioprotective effects of estrogen replacement therapy. However, randomized clinical trials have not confirmed estrogen-mediated cardioprotection. Although uncertainties about the duration and optimal type of estrogen replacement regimen might explain the disparity, other factors that may mask the protective effects of 17beta-estradiol (E2) on cardiovascular outcome need scrutiny. Increased ethanol consumption may be one such factor. We examined the effect of E2 supplementation on ethanol consumption in OVX mice and the effect of ethanol consumption on E2-mediated vascular repair, in vivo. OVX mice implanted with E2 pellets consumed significantly more ethanol, compared with those receiving placebo pellets. E2-induced increase in ethanol consumption was not affected by the absence of either estrogen receptor-alpha or -beta. Reendothelialization after carotid artery denudation was repressed, and neovascularization in ischemic hind limbs was blunted in mice consuming ethanol, despite E2 supplementation. In vitro, ethanol dose-dependently attenuated E2-induced endothelial cell (EC) proliferation and tube formation activity and enhanced EC apoptosis, suggesting that ethanol blocks E2-induced EC survival and function. Taken together our data suggest that increased ethanol consumption after E2 supplementation blunts the beneficial effects of E2 on EC function and that novel approaches to estrogen replacement for cardioprotection may benefit from the control of alcohol consumption.
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Affiliation(s)
- Johnson Rajasingh
- Division of Cardiovascular Research, Caritas St. Elizabeth's Medical Center, Tufts University School of Medicine, Boston, Massachusetts 02135, USA
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21
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22
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Shogren KL, Turner RT, Yaszemski MJ, Maran A. Double-stranded RNA-dependent protein kinase is involved in 2-methoxyestradiol-mediated cell death of osteosarcoma cells. J Bone Miner Res 2007; 22:29-36. [PMID: 17014383 PMCID: PMC1955766 DOI: 10.1359/jbmr.060914] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
UNLABELLED We studied the involvement of interferon-regulated, PKR on 2-ME-mediated actions in human osteosarcoma cells. Our results show that PKR is activated by 2-ME treatment and is necessary for 2-ME-mediated induction of osteosarcoma cell death. INTRODUCTION Osteosarcoma is the most common primary bone tumor and most frequently develops during adolescence. 2-Methoxyestradiol (2-ME), a metabolite of 17beta-estradiol, induces interferon gene expression and apoptosis in human osteosarcoma cells. In this report, we studied the role of interferon-regulated double-stranded (ds)RNA-dependent protein kinase (PKR) protein on 2-ME-mediated cell death in human osteosarcoma cells. MATERIALS AND METHODS Western blot analyses were used to measure PKR protein and phosphorylation levels. Cell survival and apoptosis assays were measured using trypan blue exclusion and Hoechst dye methods, respectively. A transient transfection protocol was used to express the dominant negative PKR mutants. RESULTS AND CONCLUSIONS PKR was increased in 2-ME-treated MG63 cells, whereas 17beta-estradiol, 4-hydroxyestradiol, and 16alpha-hydroxyestradiol, which do not induce cell death, had no effect on PKR protein levels. Also, 2-ME treatment induced PKR kinase activity as indicated by increased autophosphorylation and phosphorylation of the endogenous substrate, eukaryotic initiation factor (eIF)-2alpha. dsRNA poly (I).poly (C), an activator of PKR protein, increased cell death when osteosarcoma cells were treated with a submaximal concentration of 2-ME. In contrast, a serine-threonine kinase inhibitor SB203580 and a specific PKR inhibitor 2-aminopurine (2-AP) blocked the 2-ME-induced cell death in MG63 cells. A dominant negative PKR mutant protein conferred resistance to 2-ME-induced cell death to MG63 osteosarcoma and 2-ME-mediated PKR regulation did not require interferon gene expression. PKR protein is activated in cell free extracts by 2-ME treatment, resulting in autophosphorylation and in the phosphorylation of the substrate eIF-2alpha. We conclude from these results that PKR is regulated by 2-ME independently of interferon and is essential for 2-ME-mediated cell death in MG63 osteosarcoma cells.
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Affiliation(s)
- Kristen L Shogren
- Department of Orthopedics, Mayo Clinic College of Medicine, Rochester, Minnesota 55905, USA
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23
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Maran A, Shogren K, Zhang M, Yaszemski MJ, Hefferan TE, Spelsberg TC, Kloosterboer HJ, Turner RT. Effects of stable transfection of human fetal osteoblast cells with estrogen receptor-alpha on regulation of gene expression by tibolone. Bone 2006; 39:523-9. [PMID: 16707283 DOI: 10.1016/j.bone.2006.03.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2005] [Revised: 03/18/2006] [Accepted: 03/22/2006] [Indexed: 11/25/2022]
Abstract
Tibolone is a synthetic steroid which undergoes tissue selective metabolism into several metabolites having estrogenic, progestogenic or androgenic activities. The effects of 3 alpha-hydroxy tibolone (Org 4094), 3 beta-hydroxy tibolone (Org 30126) and their sulfated metabolites were investigated on human fetal osteoblasts (hFOB). Tibolone had no effect on selected osteoblast marker proteins in estrogen-receptor negative hFOB cells. In contrast, 3 alpha-hydroxy and 3beta-hydroxy tibolone resulted in dose-dependent increases in alkaline phosphatase activity in estrogen receptor (ER) alpha-positive hFOB cells. The maximum increase for both metabolites was comparable to the effects of an optimal dose of 17beta-estradiol, and occurred at 10 muM. At 20 muM, both metabolites increased mRNA levels for alkaline phosphatase and type 1 collagen and protein levels for osteocalcin. Sulfated metabolites of tibolone also increased alkaline phosphatase activity. The estrogen receptor antagonist ICI 182, 780 inhibited stimulation of alkaline phosphatase activity by sulfated and non-sulfated tibolone metabolites, but was more potent on the former. Taken together, these results suggest that stable transfection of ER alpha into hFOB cells confers regulation by 3 alpha-hydroxy and 3beta-hydroxy tibolone metabolites of osteoblast metabolism.
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Affiliation(s)
- A Maran
- Department of Orthopedics, Mayo Clinic College of Medicine, 3-69 Medical Sciences Building, Rochester, MN 55905, USA.
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24
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Zhang D, Trudeau VL. Integration of membrane and nuclear estrogen receptor signaling. Comp Biochem Physiol A Mol Integr Physiol 2006; 144:306-15. [PMID: 16516516 DOI: 10.1016/j.cbpa.2006.01.025] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2005] [Revised: 01/12/2006] [Accepted: 01/18/2006] [Indexed: 01/16/2023]
Abstract
The classical mechanism of estradiol (E2) action is mediated by the nuclear estrogen receptors ERalpha and ERbeta, which function as ligand-dependent transcription factors that regulate transcription of target genes containing the consensus estrogen response element (ERE) in their promoter regions. However, accumulating evidence indicates that E2 can also exert its actions through a unique membrane estrogen receptor (mER). Upon activation of the mER, various signaling pathways (i.e. Ca(2+), cAMP, protein kinase cascades) are rapidly activated and ultimately influence downstream transcription factors. Some target genes of the mER pathway may be activated independently of the nuclear estrogen receptor (nER). Additionally, it has been shown that classical nER action can be modulated by mER-initiated signaling through phosphorylation of nER and its coactivators, and by induction of third messengers (i.e. cyclin D1 and c-fos). Based on current evidence, we propose a model for E2 action integrating distinct membrane receptor and nuclear receptor signaling. This membrane receptor-nuclear receptor interaction is likely to exist for other hormones. Steroid hormones and other hormones acting through hormone receptors in the steroid receptor superfamily (i.e. thyroid hormones) also activate many of the same intracellular signaling cascades, which provides the basis for extensive crosstalk networks between hormones. The model proposed serves as a framework to investigate the diverse actions of hormones and endocrine disrupting chemicals (EDCs).
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Affiliation(s)
- Dapeng Zhang
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada
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25
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Moreira PI, Custódio J, Moreno A, Oliveira CR, Santos MS. Tamoxifen and estradiol interact with the flavin mononucleotide site of complex I leading to mitochondrial failure. J Biol Chem 2006; 281:10143-52. [PMID: 16410252 DOI: 10.1074/jbc.m510249200] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
This study evaluated the action of tamoxifen and estradiol on the function of isolated liver mitochondria. We observed that although tamoxifen and estradiol per se did not affect mitochondrial complexes II, III, or IV, complex I is affected, this effect being more drastic (except for state 4 of respiration) when mitochondria were coincubated with both drugs. Furthermore, using two respiratory chain inhibitors, rotenone and diphenyliodonium chloride, we identified the flavin mononucleotide site of complex I as the target of tamoxifen and/or estradiol action(s). Tamoxifen (25 microm) per se induced a significant increase in hydrogen peroxide production and state 4 of respiration. Additionally, a significant decrease in respiratory control ratio, transmembrane, and depolarization potentials were observed. Estradiol per se decreased carbonyl cyanide p-trifluoromethoxyphenylhydrazone (FCCP)-stimulated respiration, state 3 of respiration, and respiratory control ratio and increased lag phase of repolarization. With the exception of state 4 of respiration whose increase induced by tamoxifen was reversed by the presence of estradiol, the effects of tamoxifen were highly exacerbated when estradiol was present. We observed that 10 microm tamoxifen in the presence of estradiol affected mitochondria significantly by decreasing FCCP-stimulated respiration, state 3 of respiration, respiratory control ratio, and ADP depolarization and increasing the lag phase of repolarization. All of the deleterious effects induced by 25 microm tamoxifen were highly exacerbated in the presence of estradiol. Furthermore, we observed that the effects of both compounds were independent of estrogen receptors because the pure estrogen antagonist ICI 182,780 did not interfere with tamoxifen and/or estradiol detrimental effects. Altogether, our data provide a mechanistic explanation for the multiple cytotoxic effects of tamoxifen including its capacity to destroy tamoxifen-resistant breast cancer cells in the presence of estradiol. This new piece of information provides a basis for the development of new and promising anticancer therapeutic strategies.
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Affiliation(s)
- Paula I Moreira
- Center for Neuroscience and Cell Biology, Department of Zoology, Faculty of Sciences and Technology, University of Coimbra, 3004-517 Coimbra, Portugal
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26
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Marino M, Galluzzo P, Ascenzi P. Estrogen signaling multiple pathways to impact gene transcription. Curr Genomics 2006; 7:497-508. [PMID: 18369406 PMCID: PMC2269003 DOI: 10.2174/138920206779315737] [Citation(s) in RCA: 447] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2006] [Revised: 10/21/2006] [Accepted: 10/30/2006] [Indexed: 12/14/2022] Open
Abstract
Steroid hormones exert profound effects on cell growth, development, differentiation, and homeostasis. Their effects are mediated through specific intracellular steroid receptors that act via multiple mechanisms. Among others, the action mechanism starting upon 17beta-estradiol (E2) binds to its receptors (ER) is considered a paradigmatic example of how steroid hormones function. Ligand-activated ER dimerizes and translocates in the nucleus where it recognizes specific hormone response elements located in or near promoter DNA regions of target genes. Behind the classical genomic mechanism shared with other steroid hormones, E2 also modulates gene expression by a second indirect mechanism that involves the interaction of ER with other transcription factors which, in turn, bind their cognate DNA elements. In this case, ER modulates the activities of transcription factors such as the activator protein (AP)-1, nuclear factor-kappaB (NF-kappaB) and stimulating protein-1 (Sp-1), by stabilizing DNA-protein complexes and/or recruiting co-activators. In addition, E2 binding to ER may also exert rapid actions that start with the activation of a variety of signal transduction pathways (e.g. ERK/MAPK, p38/MAPK, PI3K/AKT, PLC/PKC). The debate about the contribution of different ER-mediated signaling pathways to coordinate the expression of specific sets of genes is still open. This review will focus on the recent knowledge about the mechanism by which ERs regulate the expression of target genes and the emerging field of integration of membrane and nuclear receptor signaling, giving examples of the ways by which the genomic and non-genomic actions of ERs on target genes converge.
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Affiliation(s)
| | | | - Paolo Ascenzi
- Department of Biology
- Interdepartmental Laboratory for Electron Microscopy, University Roma Tre, Viale Guglielmo Marconi, 446 I-00146 Roma, Italy
- National Institute for Infectious Diseases I.R.C.C.S. “Lazzaro Spallanzani”, Via Portuense 292, I-00149 Roma, Italy
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Kawana K, Kawana Y, Schust DJ. Female steroid hormones use signal transducers and activators of transcription protein-mediated pathways to modulate the expression of T-bet in epithelial cells: a mechanism for local immune regulation in the human reproductive tract. Mol Endocrinol 2005; 19:2047-59. [PMID: 15860546 DOI: 10.1210/me.2004-0489] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The transcription factor T-bet promotes the differentiation of inflammatory Th1 T helper cells. T-bet expression in lymphoid cells is regulated by cytoplasmic signaling through Janus kinase phosphorylation, nuclear signaling using signal transducers and activators of transcription (Stat) family proteins, and autocrine/paracrine feedback involving interferon (IFN)-gamma. T-bet is here shown to be present in epithelial cells of the human female reproductive tract. Regulation of T-bet expression was modulated by cytokines and the female reproductive steroids, estrogen, and progesterone. The mechanisms of T-bet regulation in epithelia differ from those in conventional immune cells. During a 15-d exposure to progesterone, T-bet levels in endometrial epithelial cells (EECs) undulated. Prior exposure to estrogen enhanced these effects. More prolonged exposure of EECs to these hormones, singly or in combination, suppressed T-bet production. Stat1 and Stat5 bound to the EEC T-bet regulatory region (TRR) at the IFN-gamma-activated sequence site, but Stat3 and Stat4 did not. Binding of Stat1 and Stat5 to the TRR were modified by progesterone in distinct ways. Estrogen suppressed the binding of Stat1 and Stat5 to the TRR. Mutation of gamma-activated sequence element reduced T-bet promoter activity, binding of Stat proteins to the TRR and regulation of the promoter by cytokines and hormones. In EECs, cytokine exposure caused phosphorylation of Janus kinase 2 and TRR-bound Stat proteins; female steroid hormones altered only phosphorylation of TRR-bound Stat5. Although there is no autocrine IFN-gamma feedback loop in reproductive tract epithelial cells, an IL-15/T-bet positive feedback loop may exist. The implications of hormonally regulated T-bet expression are discussed.
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Affiliation(s)
- Kei Kawana
- Fearing Research Laboratory, Department of Obstetrics, Gynecology, and Reproductive Biology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA
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