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Rendic SP, Guengerich FP. Formation of potentially toxic metabolites of drugs in reactions catalyzed by human drug-metabolizing enzymes. Arch Toxicol 2024; 98:1581-1628. [PMID: 38520539 DOI: 10.1007/s00204-024-03710-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Accepted: 02/20/2024] [Indexed: 03/25/2024]
Abstract
Data are presented on the formation of potentially toxic metabolites of drugs that are substrates of human drug metabolizing enzymes. The tabular data lists the formation of potentially toxic/reactive products. The data were obtained from in vitro experiments and showed that the oxidative reactions predominate (with 96% of the total potential toxication reactions). Reductive reactions (e.g., reduction of nitro to amino group and reductive dehalogenation) participate to the extent of 4%. Of the enzymes, cytochrome P450 (P450, CYP) enzymes catalyzed 72% of the reactions, myeloperoxidase (MPO) 7%, flavin-containing monooxygenase (FMO) 3%, aldehyde oxidase (AOX) 4%, sulfotransferase (SULT) 5%, and a group of minor participating enzymes to the extent of 9%. Within the P450 Superfamily, P450 Subfamily 3A (P450 3A4 and 3A5) participates to the extent of 27% and the Subfamily 2C (P450 2C9 and P450 2C19) to the extent of 16%, together catalyzing 43% of the reactions, followed by P450 Subfamily 1A (P450 1A1 and P450 1A2) with 15%. The P450 2D6 enzyme participated in an extent of 8%, P450 2E1 in 10%, and P450 2B6 in 6% of the reactions. All other enzymes participate to the extent of 14%. The data show that, of the human enzymes analyzed, P450 enzymes were dominant in catalyzing potential toxication reactions of drugs and their metabolites, with the major role assigned to the P450 Subfamily 3A and significant participation of the P450 Subfamilies 2C and 1A, plus the 2D6, 2E1 and 2B6 enzymes contributing. Selected examples of drugs that are activated or proposed to form toxic species are discussed.
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Affiliation(s)
| | - F Peter Guengerich
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, 37232-0146, USA
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2
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Nonylphenol and Octylphenol Differently Affect Cell Redox Balance by Modulating the Nitric Oxide Signaling. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2018; 2018:1684827. [PMID: 29805728 PMCID: PMC5901947 DOI: 10.1155/2018/1684827] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Accepted: 02/06/2018] [Indexed: 12/19/2022]
Abstract
Nonylphenol (NP) and octylphenol (OP) are pervasive environmental contaminants belonging to the broader class of compounds known as alkylphenols, with potential human toxic effects. Classified as “xenoestrogens,” NP and OP are able to interfere with the cell endocrine physiology via a direct interaction with the estrogen receptors. Here, using HepG2 cells in culture, the changes of the cell redox balance and mitochondrial activity induced by OP and NP have been investigated at μM concentrations, largely below those provoking acute toxicity, as those typical of environmental contaminants. Following 24 h cell exposure to both OP and NP, ROS production appeared significantly increased (p ≤ 0.01), together with the production of higher NO oxides (p = 0.003) and peroxynitrated protein-derivatives (NP versus CTR, p = 0.003). The mitochondrial proton electrochemical potential gradient instead was decreased (p ≤ 0.05), as the oxygen consumption by complex IV, particularly following incubation with NP (NP versus CTR, p = 0.017). Consistently, the RT-PCR and Western blot analyses proved that the OP and NP can modulate to a different extent the expression of the inducible NOS (NP versus CTR, p ≤ 0.01) and the endothelial NOS (OP versus CTR, p ≤ 0.05), with a significant variation of the coupling efficiency of the latter (NP versus CTR, p ≤ 0.05), a finding that may provide a novel clue to understand the specific xenoestrogenic properties of OP and NP.
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3
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Weijler AM, Schmidinger B, Kapiotis S, Laggner H, Hermann M. Oleic acid induces the novel apolipoprotein O and reduces mitochondrial membrane potential in chicken and human hepatoma cells. Biochimie 2018; 147:136-142. [PMID: 29432786 DOI: 10.1016/j.biochi.2018.02.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Accepted: 02/05/2018] [Indexed: 12/28/2022]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is marked by hepatic fat accumulation and reflects a spectrum of chronic liver diseases associated with obesity, impaired insulin sensitivity and dyslipidemia. Apolipoprotein O (ApoO) is a new member of the plasma apolipoprotein family that may play a role in lipid metabolism and electron transport activity of the mitochondrium. However, its physiological functions have not been elucidated yet. Based on our previous data in a non-mammalian experimental system [1], we hypothesized that hepatic expression of ApoO is tightly linked not only to diet-induced hepatosteatosis, but also to increased lipoprotein-production induced by, e.g., hormones and oxidative stress. To gain insight into a mammalian experimental system, we compared the effects of lipid loading on ApoO regulation in chicken hepatoma LMH cells with those in the human hepatoma cell line HepG2. Incubation of the cells with BSA-complexed oleic acid (OA-Alb) induced triglyceride accumulation, but did not affect cell viability. qPCR using specific primer pairs and Western blot analysis with in-house produced rabbit anti-ApoO antisera demonstrated significant increase in ApoO transcript and protein levels in both cell lines. ROS formation due to OA-Alb treatment was only slightly altered in LMH cells, indicating an intact antioxidant defense system of the cells. Oxidative stress applied by addition of H2O2 revealed induction of ApoO transcript and protein level in the same or even higher extent as monitored in the presence of OA-Alb. Upon treatment with estrogen for 24 h quantitative analysis of ApoO transcript and protein revealed increases of ApoO expression supporting the assumption that estrogen affects lipoprotein metabolism at various points. Furthermore, both cell lines showed a significant decrease of the mitochondrial membrane potential upon incubation with OA-Alb. Therefore, we assume that our findings support a role of ApoO as an effector of compromised mitochondrial function that likely accompanies the onset of non-alcoholic fatty liver disease.
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Affiliation(s)
- Anna M Weijler
- Department of Medical Biochemistry, Max F. Perutz Laboratories, Medical University of Vienna, Vienna, Austria
| | - Barbara Schmidinger
- Department of Medical Biochemistry, Max F. Perutz Laboratories, Medical University of Vienna, Vienna, Austria
| | - Stylianos Kapiotis
- The Central Laboratory, Hospital of the Divine Redeemer, Vienna, Austria
| | - Hilde Laggner
- Department of Medical Chemistry and Pathobiochemistry, Center of Pathobiochemistry and Genetics, Medical University of Vienna, Vienna, Austria
| | - Marcela Hermann
- Department of Medical Biochemistry, Max F. Perutz Laboratories, Medical University of Vienna, Vienna, Austria.
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4
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Galmés-Pascual BM, Nadal-Casellas A, Bauza-Thorbrügge M, Sbert-Roig M, García-Palmer FJ, Proenza AM, Gianotti M, Lladó I. 17β-estradiol improves hepatic mitochondrial biogenesis and function through PGC1B. J Endocrinol 2017; 232:297-308. [PMID: 27885055 DOI: 10.1530/joe-16-0350] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 11/24/2016] [Indexed: 11/08/2022]
Abstract
Sexual dimorphism in mitochondrial biogenesis and function has been described in many rat tissues, with females showing larger and more functional mitochondria. The family of the peroxisome proliferator-activated receptor gamma coactivator 1 (PGC1) plays a central role in the regulatory network governing mitochondrial biogenesis and function, but little is known about the different contribution of hepatic PGC1A and PGC1B in these processes. The aim of this study was to elucidate the role of 17β-estradiol (E2) in mitochondrial biogenesis and function in liver and assess the contribution of both hepatic PGC1A and PGC1B as mediators of these effects. In ovariectomized (OVX) rats (half of which were treated with E2) estrogen deficiency led to impaired mitochondrial biogenesis and function, increased oxidative stress, and defective lipid metabolism, but was counteracted by E2 treatment. In HepG2 hepatocytes, the role of E2 in enhancing mitochondrial biogenesis and function was confirmed. These effects were unaffected by the knockdown of PGC1A, but were impaired when PGC1B expression was knocked down by specific siRNA. Our results reveal a widespread protective role of E2 in hepatocytes, which is explained by enhanced mitochondrial content and oxidative capacity, lower hepatic lipid accumulation, and a reduction of oxidative stress. We also suggest a novel hepatic protective role of PGC1B as a modulator of E2 effects on mitochondrial biogenesis and function supporting activation of PGC1B as a therapeutic target for hepatic mitochondrial disorders.
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Affiliation(s)
- Bel M Galmés-Pascual
- Departament de Biologia Fonamental i Ciències de la SalutGrup Metabolisme Energètic i Nutrició, Institut Universitari d'Investigació en Ciències de la Salut (IUNICS), Universitat de les Illes Balears, Palma de Mallorca, Illes Balears, Spain
- Institut d'Investigació Sanitària de Palma (IdISPa)Hospital Universitari Son Espases, Palma de Mallorca, Illes Balears, Spain
| | - Antonia Nadal-Casellas
- Departament de Biologia Fonamental i Ciències de la SalutGrup Metabolisme Energètic i Nutrició, Institut Universitari d'Investigació en Ciències de la Salut (IUNICS), Universitat de les Illes Balears, Palma de Mallorca, Illes Balears, Spain
| | - Marco Bauza-Thorbrügge
- Departament de Biologia Fonamental i Ciències de la SalutGrup Metabolisme Energètic i Nutrició, Institut Universitari d'Investigació en Ciències de la Salut (IUNICS), Universitat de les Illes Balears, Palma de Mallorca, Illes Balears, Spain
- Institut d'Investigació Sanitària de Palma (IdISPa)Hospital Universitari Son Espases, Palma de Mallorca, Illes Balears, Spain
| | - Miquel Sbert-Roig
- Departament de Biologia Fonamental i Ciències de la SalutGrup Metabolisme Energètic i Nutrició, Institut Universitari d'Investigació en Ciències de la Salut (IUNICS), Universitat de les Illes Balears, Palma de Mallorca, Illes Balears, Spain
- Institut d'Investigació Sanitària de Palma (IdISPa)Hospital Universitari Son Espases, Palma de Mallorca, Illes Balears, Spain
| | - Francisco J García-Palmer
- Departament de Biologia Fonamental i Ciències de la SalutGrup Metabolisme Energètic i Nutrició, Institut Universitari d'Investigació en Ciències de la Salut (IUNICS), Universitat de les Illes Balears, Palma de Mallorca, Illes Balears, Spain
- Institut d'Investigació Sanitària de Palma (IdISPa)Hospital Universitari Son Espases, Palma de Mallorca, Illes Balears, Spain
- Centro de Investigación Biomédica en Red Fisiopatología de la Obesidad y la Nutrición (CIBERobn, CB06/03/0043)Instituto de Salud Carlos III, Madrid, Spain
| | - Ana M Proenza
- Departament de Biologia Fonamental i Ciències de la SalutGrup Metabolisme Energètic i Nutrició, Institut Universitari d'Investigació en Ciències de la Salut (IUNICS), Universitat de les Illes Balears, Palma de Mallorca, Illes Balears, Spain
- Institut d'Investigació Sanitària de Palma (IdISPa)Hospital Universitari Son Espases, Palma de Mallorca, Illes Balears, Spain
- Centro de Investigación Biomédica en Red Fisiopatología de la Obesidad y la Nutrición (CIBERobn, CB06/03/0043)Instituto de Salud Carlos III, Madrid, Spain
| | - Magdalena Gianotti
- Departament de Biologia Fonamental i Ciències de la SalutGrup Metabolisme Energètic i Nutrició, Institut Universitari d'Investigació en Ciències de la Salut (IUNICS), Universitat de les Illes Balears, Palma de Mallorca, Illes Balears, Spain
- Institut d'Investigació Sanitària de Palma (IdISPa)Hospital Universitari Son Espases, Palma de Mallorca, Illes Balears, Spain
- Centro de Investigación Biomédica en Red Fisiopatología de la Obesidad y la Nutrición (CIBERobn, CB06/03/0043)Instituto de Salud Carlos III, Madrid, Spain
| | - Isabel Lladó
- Departament de Biologia Fonamental i Ciències de la SalutGrup Metabolisme Energètic i Nutrició, Institut Universitari d'Investigació en Ciències de la Salut (IUNICS), Universitat de les Illes Balears, Palma de Mallorca, Illes Balears, Spain
- Institut d'Investigació Sanitària de Palma (IdISPa)Hospital Universitari Son Espases, Palma de Mallorca, Illes Balears, Spain
- Centro de Investigación Biomédica en Red Fisiopatología de la Obesidad y la Nutrición (CIBERobn, CB06/03/0043)Instituto de Salud Carlos III, Madrid, Spain
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5
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Germain D. Sirtuins and the Estrogen Receptor as Regulators of the Mammalian Mitochondrial UPR in Cancer and Aging. Adv Cancer Res 2016; 130:211-56. [PMID: 27037754 DOI: 10.1016/bs.acr.2016.01.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
By being both the source of ATP and the mediator of apoptosis, the mitochondria are key regulators of cellular life and death. Not surprisingly alterations in the biology of the mitochondria have implications in a wide array of diseases including cancer and age-related diseases such as neurodegeneration. To protect the mitochondria against damage the mitochondrial unfolded protein response (UPR(mt)) orchestrates several pathways, including the protein quality controls, the antioxidant machinery, oxidative phosphorylation, mitophagy, and mitochondrial biogenesis. While several reports have implicated an array of transcription factors in the UPR(mt), most of the focus has been on studies of Caenorhabditis elegans, which led to the identification of ATFS-1, for which the mammalian homolog remains unknown. Meanwhile, there are studies which link the UPR(mt) to sirtuins and transcription factors of the Foxo family in both C. elegans and mammalian cells but those have been largely overlooked. This review aims at emphasizing the potential importance of these studies by building on the large body of literature supporting the key role of the sirtuins in the maintenance of the integrity of the mitochondria in both cancer and aging. Further, the estrogen receptor alpha (ERα) and beta (ERβ) are known to confer protection against mitochondrial stress, and at least ERα has been linked to the UPR(mt). Considering the difference in gender longevity, this chapter also includes a discussion of the link between the ERα and ERβ and the mitochondria in cancer and aging.
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Affiliation(s)
- D Germain
- The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, NY, United States.
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6
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Tian H, Gao Z, Wang G, Li H, Zheng J. Estrogen potentiates reactive oxygen species (ROS) tolerance to initiate carcinogenesis and promote cancer malignant transformation. Tumour Biol 2015; 37:141-50. [DOI: 10.1007/s13277-015-4370-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Accepted: 11/03/2015] [Indexed: 12/25/2022] Open
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7
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Conley YP, Okonkwo DO, Deslouches S, Alexander S, Puccio AM, Beers SR, Ren D. Mitochondrial polymorphisms impact outcomes after severe traumatic brain injury. J Neurotrauma 2013; 31:34-41. [PMID: 23883111 DOI: 10.1089/neu.2013.2855] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Patient outcomes are variable following severe traumatic brain injury (TBI); however, the biological underpinnings explaining this variability are unclear. Mitochondrial dysfunction after TBI is well documented, particularly in animal studies. The aim of this study was to investigate the role of mitochondrial polymorphisms on mitochondrial function and patient outcomes out to 1 year after a severe TBI in a human adult population. The Human MitoChip V2.0 was used to evaluate mitochondrial variants in an initial set of n=136 subjects. SNPs found to be significantly associated with patient outcomes [Glasgow Outcome Scale (GOS), Neurobehavioral Rating Scale (NRS), Disability Rating Scale (DRS), in-hospital mortality, and hospital length of stay] or neurochemical level (lactate:pyruvate ratio from cerebrospinal fluid) were further evaluated in an expanded sample of n=336 subjects. A10398G was associated with DRS at 6 and 12 months (p=0.02) and a significant time by SNP interaction for DRS was found (p=0.0013). The A10398 allele was associated with greater disability over time. There was a T195C by sex interaction for GOS (p=0.03) with the T195 allele associated with poorer outcomes in females. This is consistent with our findings that the T195 allele was associated with mitochondrial dysfunction (p=0.01), but only in females. This is the first study associating mitochondrial DNA variation with both mitochondrial function and neurobehavioral outcomes after TBI in humans. Our findings indicate that mitochondrial DNA variation may impact patient outcomes after a TBI potentially by influencing mitochondrial function, and that sex of the patient may be important in evaluating these associations in future studies.
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Affiliation(s)
- Yvette P Conley
- 1 School of Nursing, University of Pittsburgh , Pittsburgh, Pennsylvania
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8
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Actions of 17β-estradiol and testosterone in the mitochondria and their implications in aging. Ageing Res Rev 2013; 12:907-17. [PMID: 24041489 DOI: 10.1016/j.arr.2013.09.001] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Accepted: 09/06/2013] [Indexed: 02/02/2023]
Abstract
A decline in the mitochondrial functions and aging are two closely related processes. The presence of estrogen and androgen receptors and hormone-responsive elements in the mitochondria represents the starting point for the investigation of the effects of 17β-estradiol and testosterone on the mitochondrial functions and their relationships with aging. Both steroids trigger a complex molecular mechanism that involves crosstalk between the mitochondria, nucleus, and plasma membrane, and the cytoskeleton plays a key role in these interactions. The result of this signaling is mitochondrial protection. Therefore, the molecular components of the pathways activated by the sexual steroids could represent targets for anti-aging therapies. In this review, we discuss previous studies that describe the estrogen- and testosterone-dependent actions on the mitochondrial processes implicated in aging.
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9
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Raval AP, Borges-Garcia R, Diaz F, Sick TJ, Bramlett H. Oral contraceptives and nicotine synergistically exacerbate cerebral ischemic injury in the female brain. Transl Stroke Res 2013; 4:402-12. [PMID: 24323338 DOI: 10.1007/s12975-013-0253-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Revised: 01/24/2013] [Accepted: 01/28/2013] [Indexed: 02/06/2023]
Abstract
Oral contraceptives (OC) and smoking-derived nicotine (N) are known to synergistically increase the risk and severity of cerebral ischemia in women. Although it has been known for some time that long-term use of OC and nicotine will have an increased risk of peripheral thrombus formation, little is known about how the combination of OC and nicotine increases severity of brain ischemia. Recent laboratory studies simulating the conditions of nicotine exposure produced by cigarette smoking and OC regimen of women in female rats confirms that the severity of ischemic hippocampal damage is far greater in female rats simultaneously exposed to OC than to nicotine alone. These studies also demonstrated that the concurrent exposure of OC and nicotine reduces endogenous 17β-estradiol levels and inhibits estrogen signaling in the brain of female rats. The endogenous 17β-estradiol plays a key role in cerebrovascular protection in women during their pre-menopausal life and loss of circulating estrogen at reproductive senescence increases both the incidence and severity of cerebrovascular diseases. Therefore, OC and nicotine induced severe post-ischemic damage might be a consequence of lack of estrogen signaling in the brain. In the present review we highlight possible mechanisms by which OC and nicotine inhibits estrogen signaling that could be responsible for severe ischemic damage in females.
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Affiliation(s)
- Ami P Raval
- Cerebral Vascular Disease Research Center, Department of Neurology, Leonard M. Miller School of Medicine, University of Miami, Two Story Lab (TSL), Room # 230A, 1420 NW 9th Avenue, Miami, FL, 33101, USA,
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10
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Shaik NA, Lone WG, Khan IA, Rao KP, Kodati VL, Hasan Q. Enhanced transcription of estrogen receptor α and mitochondrial cytochrome b genes in uterine leiomyomas. Gynecol Endocrinol 2011; 27:1094-8. [PMID: 21506659 DOI: 10.3109/09513590.2011.569610] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The relative expression levels of estrogen receptor α (ERα) and mitochondrial cytochrome b (MTCYB) transcripts and their association with ERα, -397T > C gene polymorphism was determined in premenopausal uterine leiomyomas and myometrium tissues to gain an insight into the role of ER-mediated action of estrogen on mitochondrial gene transcription. Both ERα and MTCYB transcripts were overexpressed in leiomyomas compared with myometrium tissues with 9.18 ± 0.79 folds and 5.24 ± 0.48 folds, respectively. ERα demonstrated ≥1.7 folds overexpression expressed over MTCYB (p < 0.001). Genotype correlation with transcript expression revealed that leiomyomas with CC genotype had significantly increased levels of ERα with 11.9 ± 1.02 folds as compared with 6.46 ± 0.56 folds seen in CT and TT genotypes together (p < 0.001). Interestingly, MTCYB transcript levels were also >1.9 folds overexpressed in leiomyomas with the CC genotype as compared with leiomyomas with other genotypes (p < 0.01).Significant elevation of ERα and MTCYB transcript levels in premenopausal leiomyomas and its association with ERα, -397 CC genotype suggests the mitochondrial-mediated role of estrogen as the promoter of leiomyoma tumorigenesis.
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Affiliation(s)
- Noor Ahmad Shaik
- Department of Genetics, Vasavi Medical and Research Centre, Khairatabad, Hyderabad, 500 004, India
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Simpkins JW, Yi KD, Yang SH, Dykens JA. Mitochondrial mechanisms of estrogen neuroprotection. Biochim Biophys Acta Gen Subj 2009; 1800:1113-20. [PMID: 19931595 DOI: 10.1016/j.bbagen.2009.11.013] [Citation(s) in RCA: 115] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2009] [Revised: 11/11/2009] [Accepted: 11/12/2009] [Indexed: 01/11/2023]
Abstract
Mitochondria have become a primary focus in our search not only for the mechanism(s) of neuronal death but also for neuroprotective drugs and therapies that can delay or prevent Alzheimer's disease and other chronic neurodegenerative conditions. This is because mitochrondria play a central role in regulating viability and death of neurons, and mitochondrial dysfunction has been shown to contribute to neuronal death seen in neurodegenerative diseases. In this article, we review the evidence for the role of mitochondria in cell death and neurodegeneration and provide evidence that estrogens have multiple effects on mitochondria that enhance or preserve mitochondrial function during pathologic circumstances such as excitotoxicity, oxidative stress, and others. As such, estrogens and novel non-hormonal analogs have come to figure prominently in our efforts to protect neurons against both acute brain injury and chronic neurodegeneration.
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Affiliation(s)
- James W Simpkins
- Department of Pharmacology & Neuroscience, Institute for Aging and Alzheimer's Disease Research, University of North Texas Health Science Center, Fort Worth, TX, USA.
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12
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Chen J, Russo J. Mitochondrial oestrogen receptors and their potential implications in oestrogen carcinogenesis in human breast cancer. ACTA ACUST UNITED AC 2009. [DOI: 10.1080/13590840801972074] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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13
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Role of protein phosphatases and mitochondria in the neuroprotective effects of estrogens. Front Neuroendocrinol 2009; 30:93-105. [PMID: 19410596 PMCID: PMC2835549 DOI: 10.1016/j.yfrne.2009.04.013] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2009] [Revised: 04/20/2009] [Accepted: 04/21/2009] [Indexed: 12/15/2022]
Abstract
In the present treatise, we provide evidence that the neuroprotective and mito-protective effects of estrogens are inexorably linked and involve the ability of estrogens to maintain mitochondrial function during neurotoxic stress. This is achieved by the induction of nuclear and mitochondrial gene expression, the maintenance of protein phosphatases levels in a manner that likely involves modulation of the phosphorylation state of signaling kinases and mitochondrial pro- and anti-apoptotic proteins, and the potent redox/antioxidant activity of estrogens. These estrogen actions are mediated through a combination of estrogens receptor (ER)-mediated effects on nuclear and mitochondrial transcription of protein vital to mitochondrial function, ER-mediated, non-genomic signaling and non-ER-mediated effects of estrogens on signaling and oxidative stress. Collectively, these multifaceted, coordinated action of estrogens leads to their potency in protecting neurons from a wide variety of acute insults as well as chronic neurodegenerative processes.
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Chen JQ, Cammarata PR, Baines CP, Yager JD. Regulation of mitochondrial respiratory chain biogenesis by estrogens/estrogen receptors and physiological, pathological and pharmacological implications. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2009; 1793:1540-70. [PMID: 19559056 DOI: 10.1016/j.bbamcr.2009.06.001] [Citation(s) in RCA: 189] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2009] [Revised: 06/16/2009] [Accepted: 06/17/2009] [Indexed: 12/21/2022]
Abstract
There has been increasing evidence pointing to the mitochondrial respiratory chain (MRC) as a novel and important target for the actions of 17beta-estradiol (E(2)) and estrogen receptors (ER) in a number of cell types and tissues that have high demands for mitochondrial energy metabolism. This novel E(2)-mediated mitochondrial pathway involves the cooperation of both nuclear and mitochondrial ERalpha and ERbeta and their co-activators on the coordinate regulation of both nuclear DNA- and mitochondrial DNA-encoded genes for MRC proteins. In this paper, we have: 1) comprehensively reviewed studies that reveal a novel role of estrogens and ERs in the regulation of MRC biogenesis; 2) discussed their physiological, pathological and pharmacological implications in the control of cell proliferation and apoptosis in relation to estrogen-mediated carcinogenesis, anti-cancer drug resistance in human breast cancer cells, neuroprotection for Alzheimer's disease and Parkinson's disease in brain, cardiovascular protection in human heart and their beneficial effects in lens physiology related to cataract in the eye; and 3) pointed out new research directions to address the key questions in this important and newly emerging area. We also suggest a novel conceptual approach that will contribute to innovative regimens for the prevention or treatment of a wide variety of medical complications based on E(2)/ER-mediated MRC biogenesis pathway.
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Affiliation(s)
- Jin-Qiang Chen
- Breast Cancer Research Laboratory, Fox Chase Cancer Center, Philadelphia, PA 19111, USA.
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15
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Chen JQ, Brown TR, Russo J. Regulation of energy metabolism pathways by estrogens and estrogenic chemicals and potential implications in obesity associated with increased exposure to endocrine disruptors. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2009; 1793:1128-43. [PMID: 19348861 DOI: 10.1016/j.bbamcr.2009.03.009] [Citation(s) in RCA: 124] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 02/19/2009] [Revised: 03/26/2009] [Accepted: 03/27/2009] [Indexed: 10/20/2022]
Abstract
The prevalence of obesity among children, adolescents and adults has been dramatically increasing worldwide during the last several decades. The obesity epidemic has been recognized as one of the major global health problems, because its health hazard is linked to a number of common diseases including breast and prostate cancers. Obesity is caused by combination of genetic and environmental factors. While genetic contribution to obesity has been known to be significant, the genetic factors remain relatively unchanged. Recent studies have highlighted the involvement of environmental "obesogens", i.e. the xenobiotic chemicals that can disrupt the normal development and homeostatic control over adipogenesis and energy balance. Several lines of evidence suggest that increasing exposure to chemicals with endocrine-disrupting activities (endocrine-disrupting chemicals, EDCs) contributes to the increased obesity. The cellular and molecular mechanisms underlying obesogen-associated obesity are just now being appreciated. In this paper, we comprehensively reviewed current knowledge about the role of estrogen receptors alpha and beta (ERalpha and ERbeta) in regulation of energy metabolism pathways, including glucose transport, glycolysis, tricarboxylic acid (TCA) cycle, mitochondrial respiratory chain (MRC), adenosine nucleotide translocator (ANT) and fatty acid beta-oxidation and synthesis, by estrogens; and then examined the disturbance of E(2)/ER-mediated energy metabolism pathways by environmental obesogens; and finally, we discussed the potential implications of disturbance of energy metabolism pathways by obesogens in obesity and pointed out several key aspects of this area that need to be further explored. A better understanding of the cellular and molecular mechanisms underlying obesogen-associated obesity will lead to new approaches for slow down and/or prevention of the increased trend of obesity associated with exposure to obesogens.
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Affiliation(s)
- Jin-Qiang Chen
- Breast Cancer Research Laboratory, Fox Chase Cancer Center, Philadelphia, PA, 19111, USA.
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Kalra M, Mayes J, Assefa S, Kaul AK, Kaul R. Role of sex steroid receptors in pathobiology of hepatocellular carcinoma. World J Gastroenterol 2008; 14:5945-61. [PMID: 18932272 PMCID: PMC2760195 DOI: 10.3748/wjg.14.5945] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The striking gender disparity observed in the incidence of hepatocellular carcinoma (HCC) suggests an important role of sex hormones in HCC pathogenesis. Though the studies began as early as in 1980s, the precise role of sex hormones and the significance of their receptors in HCC still remain poorly understood and perhaps contribute to current controversies about the potential use of hormonal therapy in HCC. A comprehensive review of the existing literature revealed several shortcomings associated with the studies on estrogen receptor (ER) and androgen receptor (AR) in normal liver and HCC. These shortcomings include the use of less sensitive receptor ligand binding assays and immunohistochemistry studies for ERα alone until 1996 when ERβ isoform was identified. The animal models of HCC utilized for studies were primarily based on chemical-induced hepatocarcinogenesis with less similarity to virus-induced HCC pathogenesis. However, recent in vitro studies in hepatoma cells provide newer insights for hormonal regulation of key cellular processes including interaction of ER and AR with viral proteins. In light of the above facts, there is an urgent need for a detailed investigation of sex hormones and their receptors in normal liver and HCC. In this review, we systematically present the information currently available on androgens, estrogens and their receptors in normal liver and HCC obtained from in vitro, in vivo experimental models and clinical studies. This information will direct future basic and clinical research to bridge the gap in knowledge to explore the therapeutic potential of hormonal therapy in HCC.
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Chen JQ, Brown TR, Yager JD. Mechanisms of hormone carcinogenesis: evolution of views, role of mitochondria. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2008. [PMID: 18637481 DOI: 10.1007/978-0-387-78818-0_1] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
CumuIative and excessive exposure to estrogens is associated with increased breast cancer risk. The traditional mechanism explaining this association is that estrogens affect the rate of cell division and apoptosis and thus manifest their effect on the risk of breast cancer by affecting the growth of breast epithelial tissues. Highly proliferative cells are susceptible to genetic errors during DNA replication. The action of estrogen metabolites offers a complementary genotoxic pathway mediated by the generation of reactive estrogen quinone metabolites that can form adducts with DNA and generate reactive oxygen species through redox cycling. In this chapter, we discussed a novel mitochondrial pathway mediated by estrogens and their cognate estrogen receptors (ERs) and its potential implications in estrogen-dependent carcinogenesis. Several lines of evidence are presented to show: (1) mitochondrial localization of ERs in human breast cancer cells and other cell types; (2) a functional role for the mitochondrial ERs in regulation of the mitochondrial respiratory chain (MRC) proteins and (3) potential implications of the mitochondrial ER-mediated pathway in stimulation of cell proliferation, inhibition of apoptosis and oxidative damage to mitochondrial DNA. The possible involvement of estrogens and ERs in deregulation of mitochondrial bioenergetics, an important hallmark of cancer cells, is also described. An evolutionary view is presented to suggest that persistent stimulation by estrogens through ER signaling pathways of MRC proteins and energy metabolic pathways leads to the alterations in mitochondrial bioenergetics and contributes to the development of estrogen-related cancers.
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Affiliation(s)
- Jin-Qiang Chen
- Division of Pulmonary and Critical Care, Department of Medicine, University of Virginia School of Medicine, Charlottesville, VA 22908-0546, USA.
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18
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Chen JQ, Russo PA, Cooke C, Russo IH, Russo J. ERbeta shifts from mitochondria to nucleus during estrogen-induced neoplastic transformation of human breast epithelial cells and is involved in estrogen-induced synthesis of mitochondrial respiratory chain proteins. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2007; 1773:1732-46. [PMID: 17604135 DOI: 10.1016/j.bbamcr.2007.05.008] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2007] [Revised: 04/28/2007] [Accepted: 05/10/2007] [Indexed: 02/06/2023]
Abstract
Both estrogen receptors (ER) alpha (ERalpha) and beta (ERbeta) are localized in the nucleus, plasma membrane, and mitochondria, where they mediate the different physiological effects of estrogens. It has been observed that the relative subcellular localization of ERs is altered in several cancer cells. We have demonstrated that MCF-10F cells, the immortal and non-tumorigenic human breast epithelial cells (HBEC) that are ERalpha-negative and ERbeta-positive, are transformed in vitro by 17beta-estradiol (E(2)), generating highly invasive cells that are tumorigenic in severe combined immunodeficient mice. E(2)-transformed MCF-10F (trMCF) cells exhibit progressive loss of ductulogenesis, invasive (bsMCF) and tumorigenic (caMCF) phenotypes. Immunolocalization of ERbeta by confocal fluorescent microscopy and electron microscopy revealed that ERbeta is predominantly localized in mitochondria of MCF-10F and trMCF cells. Silencing ERbeta expression with ERbeta-specific small interference RNA (siRNA-ERbeta) markedly diminishes both nuclear and mitochondrial ERbeta in MCF-10F cells. The ERbeta shifts from its predominant localization in the mitochondria of MCF-10F and trMCF cells to the nucleus of bsMCF cells, becoming predominantly nuclear in caMCF cells. Furthermore, we demonstrated that the mitochondrial ERbeta in MCF-10F cells is involved in E(2)-induced expression of mitochondrial DNA (mtDNA)-encoded respiratory chain (MRC) proteins. This is the first report of an association of changes in the subcellular localization of ERbeta with various stages of E(2)-induced transformation of HBEC and a functional role of mitochondrial ERbeta in mediating E(2)-induced MRC protein synthesis. Our findings provide a new insight into one of the potential roles of ERbeta in human breast cancer.
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Affiliation(s)
- Jin-Qiang Chen
- Breast Cancer Research Laboratory, Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, PA 19111-2497, USA.
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19
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Moens LN, Soetaert A, van der Ven K, Del-Favero J, De Coen WM. Use of suppression subtractive hybridization PCR for the development of cDNA arrays for the detection of endocrine disruption in carp (Cyprinus carpio). COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY D-GENOMICS & PROTEOMICS 2007; 2:18-33. [DOI: 10.1016/j.cbd.2006.10.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2006] [Revised: 10/05/2006] [Accepted: 10/13/2006] [Indexed: 09/30/2022]
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20
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Mazzanti R, Giulivi C. Coordination of nuclear- and mitochondrial-DNA encoded proteins in cancer and normal colon tissues. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2006; 1757:618-23. [PMID: 16730322 DOI: 10.1016/j.bbabio.2006.04.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2005] [Revised: 03/17/2006] [Accepted: 04/06/2006] [Indexed: 11/29/2022]
Abstract
To support the rapid growth of tumors, the cell can respond by increasing the number of mitochondria, in a concerted biosynthesis of mitochondrial constituents (nuclear and mitochondria encoded). Increased transcription, availability and stability of oxidative phosphorylation mRNAs, without increasing mitochondria number could also lead to more rapid energy-yielding effects. Mitochondria biogenesis and de novo formation of respiratory chain components imply coordination of nuclear and mt gene transcription. The mitochondrial mass is regulated by a number of physiopathological conditions. In response to external stimuli, mitochondria biogenesis is dependent on an orchestrated crosstalk between the nuclear and the mitochondrial genomes. Based on the higher incidence of glycolysis over oxidative phosphorylation in cancer tissues, we studied by differential proteomics the energy metabolism pathway of matched samples of normal and cancer tissue. Our results indicated that oxidative phosphorylation in cancer cells seemed altered because there is an unbalanced coordination between nuclear- and mitochondria-encoded mitochondrial proteins.
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Affiliation(s)
- Roberto Mazzanti
- Department Internal Medicine, University of Florence, Florence, Italy
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21
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Solakidi S, Psarra AMG, Sekeris CE. Differential subcellular distribution of estrogen receptor isoforms: localization of ERalpha in the nucleoli and ERbeta in the mitochondria of human osteosarcoma SaOS-2 and hepatocarcinoma HepG2 cell lines. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2006; 1745:382-92. [PMID: 15993498 DOI: 10.1016/j.bbamcr.2005.05.010] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2005] [Revised: 05/13/2005] [Accepted: 05/16/2005] [Indexed: 11/28/2022]
Abstract
The localization of estrogen receptors alpha (ERalpha) and beta (ERbeta) in osteosarcoma SaOS-2 and hepatocarcinoma HepG2 cells was studied by immunofluorescence labelling and confocal laser scanning microscopy, as well as by subcellular fractionation and immunoblotting of the proteins of the fractions with respective antibodies. In both cell types, ERalpha was localized mainly in the nucleus, particularly concentrated on nuclear structures, which on the basis of their staining with pyronin and with antibodies against the nucleoli-specific Ki67 antigen and C23-nucleolin, were characterized as nucleoli. A faint, diffuse ERalpha staining was also observed in the cytoplasm. ERbeta was specifically enriched at the site of the mitochondria, visualized by labelling with the vital dye CMX and antibody against the mitochondrial-specific cytochrome oxidase subunit I. Immunoblotting experiments corroborated the immunofluorescence labelling distribution of ERalpha and ERbeta. These findings support the concept of a direct action of steroid/thyroid hormones on mitochondrial functions by way of their cognate receptors and also suggest a direct involvement of ERalpha in nucleolar-related processes.
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Affiliation(s)
- S Solakidi
- National Hellenic Research Foundation, Institute of Biological Research and Biotechnology, Laboratory of Molecular Endocrinology, 48 Vas Constantinou Avenue, 11635, Athens, Greece
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22
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Psarra AMG, Solakidi S, Sekeris CE. The mitochondrion as a primary site of action of steroid and thyroid hormones: presence and action of steroid and thyroid hormone receptors in mitochondria of animal cells. Mol Cell Endocrinol 2006; 246:21-33. [PMID: 16388892 DOI: 10.1016/j.mce.2005.11.025] [Citation(s) in RCA: 108] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Mitochondria are key cellular organelles that regulate events related to energy production and apoptosis. These processes are modulated, in turn, by steroid and thyroid hormones in the course of their actions on metabolism, growth and development. In this context, a direct effect of these hormones on the mitochondrial-linked processes, possibly by way of cognate mitochondrial receptors, has been proposed. In this paper we review data from the literature and present new findings supporting this concept. Receptors for steroid hormones, glucocorticoids and estrogens, and for T(3), have been detected in mitochondria by immunofluorescence labeling and confocal laser microscopy, by Western blotting of mitochondrial proteins and by immunogold electron microscopy. Furthermore, the mitochondrial genome contains nucleotide sequences with high similarity to known hormone-responsive elements, which interact with the appropriate receptors to confer hormone-dependent activation of reporter genes in transfection experiments. Thus, thyroid hormone stimulates mitochondrial transcription mediated by the cognate receptor when added to an in organello mitochondrial system, capable of faithful transcription.
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Affiliation(s)
- A-M G Psarra
- Foundation for Biomedical Research of the Academy of Athens, Center for Basic Research, Athens, Greece
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Chen JQ, Yager JD, Russo J. Regulation of mitochondrial respiratory chain structure and function by estrogens/estrogen receptors and potential physiological/pathophysiological implications. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2005; 1746:1-17. [PMID: 16169101 DOI: 10.1016/j.bbamcr.2005.08.001] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2005] [Revised: 08/03/2005] [Accepted: 08/03/2005] [Indexed: 01/11/2023]
Abstract
It is well known that the biological and carcinogenic effects of 17beta-estradiol (E2) are mediated via nuclear estrogen receptors (ERs) by regulating nuclear gene expression. Several rapid, non-nuclear genomic effects of E2 are mediated via plasma membrane-bound ERs. In addition, there is accumulating evidence suggesting that mitochondria are also important targets for the action of estrogens and ERs. This review summarized the studies on the effects of estrogens via ERs on mitochondrial structure and function. The potential physiological and pathophysiological implications of deficiency and/or overabundance of these E2/ER-mediated mitochondrial effects in stimulation of cell proliferation, inhibition of apoptosis, E2-mediated cardiovascular and neuroprotective effects in target cells are also discussed.
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Affiliation(s)
- Jin-Qiang Chen
- Breast Cancer Research Laboratory, Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, PA 19111, USA.
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24
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Mukhopadhyay S, Mukherjee TK. Bridging advanced glycation end product, receptor for advanced glycation end product and nitric oxide with hormonal replacement/estrogen therapy in healthy versus diabetic postmenopausal women: A perspective. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2005; 1745:145-55. [PMID: 15890418 DOI: 10.1016/j.bbamcr.2005.03.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2005] [Revised: 03/20/2005] [Accepted: 03/22/2005] [Indexed: 12/13/2022]
Abstract
Cardiovascular diseases (CVD) are the most significant cause of death in postmenopausal women. The loss of estrogen biosynthesis with advanced age is suggested as one of the major causes of higher CVD in postmenopausal women. While some studies show beneficial effects of estrogen therapy (ET)/hormonal replacement therapy (HRT) in the cardiovascular system of healthy postmenopausal women, similar studies in diabetic counterparts contradict these findings. In particular, ET/HRT in diabetic postmenopausal women results in a seemingly detrimental effect on the cardiovascular system. In this review, the comparative role of estrogens is discussed in the context of CVD in both healthy and diabetic postmenopausal women in regard to the synthesis or expression of proinflammatory molecules like advanced glycation end products (AGEs), receptor for advanced glycation end products (RAGEs), inducible nitric oxide synthases (iNOS) and the anti-inflammatory endothelial nitric oxide synthases (eNOS). The interaction of AGE-RAGE signaling with molecular nitric oxide (NO) may determine the level of reactive oxygen species (ROS) and influence the overall redox status of the vascular microenvironment that may further determine the ultimate outcome of the effects of estrogens on the CVD in healthy versus diabetic women.
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Affiliation(s)
- Srirupa Mukhopadhyay
- Pulmonary Division, Department of Internal Medicine, University of Utah Health Science Center, Rm 725 Wintrobe Building, 26 North 1900 East, Salt Lake City, UT 84132-4701, USA
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Felty Q, Roy D. Estrogen, mitochondria, and growth of cancer and non-cancer cells. J Carcinog 2005; 4:1. [PMID: 15651993 PMCID: PMC548143 DOI: 10.1186/1477-3163-4-1] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2004] [Accepted: 01/15/2005] [Indexed: 02/07/2023] Open
Abstract
In this review, we discuss estrogen actions on mitochondrial function and the possible implications on cell growth. Mitochondria are important targets of estrogen action. Therefore, an in-depth analysis of interaction between estrogen and mitochondria; and mitochondrial signaling to nucleus are pertinent to the development of new therapy strategies for the treatment of estrogen-dependent diseases related to mitochondrial disorders, including cancer.
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Affiliation(s)
- Quentin Felty
- Department of Environmental Health Sciences, University of Alabama at Birmingham, Birmingham, AL, 35294-0022 USA
| | - Deodutta Roy
- Department of Environmental Health Sciences, University of Alabama at Birmingham, Birmingham, AL, 35294-0022 USA
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26
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Felty Q, Roy D. Mitochondrial signals to nucleus regulate estrogen-induced cell growth. Med Hypotheses 2005; 64:133-41. [PMID: 15533631 DOI: 10.1016/j.mehy.2003.12.056] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2003] [Accepted: 12/18/2003] [Indexed: 10/26/2022]
Abstract
Classical genomic and non-genomic signaling pathways mediated by nuclear and cell membrane estrogen receptors are considered to contribute to estrogen-induced cell proliferation. Here we propose that mitochondrial signals to the nucleus regulate estrogen-induced progression of the cell cycle. The influence of estrogen on mitochondrial oxidative phosphorylation and mitochondrial gene transcription support the idea that mitochondria are significant targets of estrogen. Mitochondria are the major source of reactive oxygen species (ROS) in epithelial cells. Estrogen redox cycling within mitochondria also generates ROS. Antioxidants inhibit estrogen-induced cell growth. A-Raf, Akt, PKC, MEK, ERK, and transcription factors AP-1, NF-kappaB, and CREB are targets of both estrogen and ROS. We provide four lines of evidence in support of our hypothesis that estrogen-induced mitochondrial ROS stimulate redox sensor kinase A-Raf, Akt or PKC, which, in turn, activate transcription factors NF-kappaB, CREB, or AP-1 via the MEK/ERK pathway. Thus, estrogen-induced mitochondrial ROS leading to the activation of cell cycle genes containing AP-1, NF-kappaB, or CREB response elements are involved in the progression of the cell cycle of the estrogen-dependent cells. Our novel concept will contribute to the development of new targets in the prevention and control of estrogen-induced disease including cancer.
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Affiliation(s)
- Quentin Felty
- Department of Environmental Health Sciences, University of Alabama at Birmingham, Birmingham, AL 35294-0022, USA
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27
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He QY, Chen J, Kung HF, Yuen APW, Chiu JF. Identification of tumor-associated proteins in oral tongue squamous cell carcinoma by proteomics. Proteomics 2004; 4:271-8. [PMID: 14730689 DOI: 10.1002/pmic.200300550] [Citation(s) in RCA: 111] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Oral tongue carcinoma is an aggressive tumor that particularly affects chronic smokers, drinkers and betel squid chewers. Patients often present symptoms at a late stage, and there is a high recurrence rate after treatment. In this article, we report the first proteomic analysis of oral tongue carcinoma to globally search for tumor related proteins. Apart from helping us to understand the molecular pathogenesis of the carcinoma, these proteins may also have potential clinical applications as biomarkers, enabling the tumor to be identified at an early stage in high risk individuals, treatment response to be predicted, and residual or recurrent carcinoma to be detected sooner after treatment. The protein expression profiles of ten oral tongue squamous cell carcinomas and their matched normal mucosal resection margins were examined by two-dimensional gel electrophoresis and matrix-assisted laser desorption/ionization-time of flight mass spectroscopy. A number of tumor-associated proteins including heat shock protein (HSP)60, HSP27, alpha B-crystalline, ATP synthase beta, calgranulin B, myosin, tropomyosin and galectin 1 were consistently found to be significantly altered in their expression levels in tongue carcinoma tissues, compared with their paired normal mucosae. The expression profile portrays a global protein alteration that appears specific to oral tongue cancer. The potential of utilizing these tumor related proteins for screening cancer and monitoring recurrence warrants further investigation.
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Affiliation(s)
- Qing-Yu He
- Department of Chemistry, University of Hong Kong, Hong Kong, China.
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28
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Chen JQ, Delannoy M, Cooke C, Yager JD. Mitochondrial localization of ERalpha and ERbeta in human MCF7 cells. Am J Physiol Endocrinol Metab 2004; 286:E1011-22. [PMID: 14736707 DOI: 10.1152/ajpendo.00508.2003] [Citation(s) in RCA: 217] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We observed previously that estrogen treatment increased the transcript levels of several mitochondrial DNA (mtDNA)-encoded genes for mitochondrial respiratory chain (MRC) proteins and MRC activity in rat hepatocytes and human Hep G2 cells. Others have reported detection of estrogen receptors (ER), ERalpha and ERbeta, in mitochondria of rabbit ovarian and uterine tissue. In this study, we have extended these observations. Using cellular fractionation and Western blot with ERalpha- and ERbeta-specific antibodies, we observed that ERalpha and ERbeta are present in mitochondria of human MCF7 cells and that the mitochondrial ERalpha and ERbeta account for 10 and 18%, respectively, of total cellular ERalpha and ERbeta in 17beta-estradiol (E(2))-treated MCF7 cells. We also found that E(2) significantly enhanced the amounts of mitochondrial ERalpha and ERbeta in a time- and concentration-dependent manner and that these effects are accompanied by a significant increase in the transcript levels of mtDNA-encoded genes, i.e., cytochrome c oxidase subunits I and II. Moreover, we demonstrated that these E(2)-mediated effects were inhibited by the pure ER antagonist, ICI-182780, indicating the involvement of ERs. Using immunohistochemistry with confocal microscopy and immunogold electron microscopy, we demonstrated that ERalpha and ERbeta are located within the MCF7 cell mitochondrial matrix. Computer analysis identified a putative internal mitochondrial targeting peptide signal within human ERbeta, suggesting an inherent potential for ERbeta to enter mitochondria. These findings confirm the observations of others and provide additional support for this novel localization of the ERs and for a potentially important role of the ER in the regulation of mtDNA transcription.
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Affiliation(s)
- Jin Q Chen
- Division of Toxicological Sciences, Department of Environmental Health Sciences, Bloomberg School of Public Health, Johns Hopkins School of Medicine, Baltimore, Maryland 21205, USA
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29
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Chen JQ, Eshete M, Alworth WL, Yager JD. Binding of MCF-7 cell mitochondrial proteins and recombinant human estrogen receptors ? and ? to human mitochondrial dna estrogen response elements. J Cell Biochem 2004; 93:358-73. [PMID: 15368362 DOI: 10.1002/jcb.20178] [Citation(s) in RCA: 116] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Our previous studies have shown that 17beta estradiol (E2) enhances the transcript levels of mitochondrial DNA (mtDNA)-encoded genes and mitochondrial respiratory chain (MRC) activity via estrogen receptors (ER). Others have reported the presence of putative estrogen responsive elements (ERE) in human mtDNA (mtEREs) and detection of ERs in mitochondria of rat uterine and ovary cells. Recently, we demonstrated the E2-enhanced mitochondrial localization of ERalpha and ERbeta, and E2-induced mtDNA transcript levels in MCF-7 cells. In this study, we applied electrophoresis mobility shift assays (EMSAs) and surface plasmon resonance (SPR) to determine if mitochondrial extracts, recombinant human ERalpha (rhERalpha), and rhERbeta interact with mtEREs. Using EMSAs, we observed that ER-containing mitochondrial extracts bound to mtEREs and the binding was enhanced by E2, whereas the binding of mitochondrial proteins from ERbeta-deficient cells was almost undetectable. Both rhERalpha and rhERbeta bound to the mtEREs and their binding was altered by their respective antibodies. However, the ERalpha antibodies did not alter the binding of MCF-7 cell mitochondrial extracts to mtEREs whereas the binding MCF-7 and MDA-MB-231 cell mitochondrial extracts to mtEREs was reduced by ERbeta antibody. These results suggest that the mtERE-bound mitochondrial protein is ERbeta. Using SPR, we observed the binding of both ERs to mtEREs and that the binding was increased by E2. These results indicate that the mitochondrial ERs can interact with mtEREs and suggest that they may be directly involved in E2 induction of mtDNA transcription.
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Affiliation(s)
- Jin Q Chen
- Department of Environmental Health Sciences, Division of Toxicological Sciences, Johns Hopkins University Bloomberg School of Public Health, 615 N. Wolfe St. Baltimore, Maryland 21205-2179, USA.
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Hong S, Pedersen PL. Subunit E of mitochondrial ATP synthase: a bioinformatic analysis reveals a phosphopeptide binding motif supporting a multifunctional regulatory role and identifies a related human brain protein with the same motif. Proteins 2003; 51:155-61. [PMID: 12660984 DOI: 10.1002/prot.10318] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
The mitochondrial adenosine triphosphate (ATP) synthase is located in the inner membrane and consists of at least 16 subunit types in animals, one of which is subunit e, the function of which is not clearly defined. A highly homologous protein is located in the nucleus and named progesterone receptor binding protein (RBF), to designate its role in this organelle. In addition, the expression level of subunit e in mammalian cells fluctuates greatly and is induced by certain carcinogens and elevated in liver cancers. Because these previous observations suggested to us that subunit e may play multifunctional regulatory roles, we employed a bioinformatic approach to test this view. First, from sequence alignment studies, secondary structure analyses, and basic local alignment search tool (BLAST) searches, we concluded that mitochondrial subunit e and the homologous nuclear protein RBF are most likely the same protein. Second, we examined the known sequence and structure of one of the most common multifunctional cell regulatory proteins, the 14-3-3 protein, involved in phosphopeptide binding, and deduced that it has an apparent binding motif (-KX(6)R---RY-). Third, from careful examination of the conserved residues within all subunit e sequences in the database, we discovered that this protein has a comparable binding motif (-RY---KX(6)R-). Finally, in a BLAST search for additional homologs of subunit e, we found a human brain protein, KIAA1578, the C-terminal 30 amino acids of which are identical to those of human subunit e. This protein also contains a potential phosphopeptide binding motif. In summary, these studies provide support for the view that subunit e is a multifunctional cell regulator involved in cell signaling, and implicate the involvement of the KIAA1578 protein in cell signaling as well. These studies suggest also that, while functioning as a subunit of mitochondrial ATP synthases, subunit e may help regulate these complexes by binding to phosphopeptides within one or more of the other subunit types.
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Affiliation(s)
- Sangjin Hong
- Department of Biological Chemistry, Johns Hopkins University, School of Medicine, Baltimore, Maryland 21205-2185, USA
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31
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Verlaet M, Duyckaerts C, Rahmouni S, Denis G, Humblet C, Greimers R, Sluse FE, Boniver J, Defresne MP. Transient modifications of respiratory capacity in thymic cells during murine radioleukemogenesis. Free Radic Biol Med 2002; 33:76-82. [PMID: 12086685 DOI: 10.1016/s0891-5849(02)00858-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The evolution of mitochondrial oxidative phosphorylation was studied during cancer induction in a model of thymic radiolymphomagenesis in C57BL/Ka mice. During the preneoplastic period, thymuses displayed an increase of the cytochrome c oxidase activity and oxygen consumption together with oxidative DNA damage assessed by the presence of the 8-hydroxydeoxyguanine DNA base modification. These transient changes in mitochondrial functional activity were not observed in thymuses of mice rescued from lymphoma development by a bone marrow graft, suggesting an important role of mitochondria for neoplastic transformation in this model, which might therefore be of interest to test the utilization of antioxidants for the prevention of radiation-induced malignancies.
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Affiliation(s)
- Myriam Verlaet
- Laboratory of Pathological Anatomy and Cytology, University of Liège, Liège, Belgium.
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Monje P, Boland R. Subcellular distribution of native estrogen receptor alpha and beta isoforms in rabbit uterus and ovary. J Cell Biochem 2001; 82:467-79. [PMID: 11500923 DOI: 10.1002/jcb.1182] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The association of estrogen receptors with non-nuclear/cytoplasmic compartments in target tissues has been documented. However, limited information is available on the distribution of estrogen receptor isoforms, specially with regard to the newly described beta isotype. The subcellular localization of estrogen receptor alpha and beta isoforms was investigated in rabbit uterus and ovary. Native alpha and beta subtypes were immunodetected using specific antibodies after subjecting the tissue to fractionation by differential centrifugation. The ovary expressed alpha and beta estrogen receptors in predominant association to cytosolic components. However, in the uterus, a substantial proportion of the total estrogen binding capacity and coexpression of the two isoforms was detected in mitochondria and microsomes. The mitochondrial-enriched subfraction represented an important source of 17beta-estradiol binding, where the steroid was recognized in a stereospecific and high affinity manner. The existence of mitochondrial and membrane estrogen binding sites correlated with the presence of estrogen receptor alpha but mainly with estrogen receptor beta proteins. Using macromolecular 17beta-estradiol derivatives in Ligand Blot studies, we could confirm that both alpha and beta isoforms were expressed as the major estrogen binding proteins in the uterus, while estrogen receptor alpha was clearly the dominant isoform in the ovary. Other low molecular weight estrogen receptor alpha-like proteins were found to represent an independent subpopulation of uterine binding sites, expressed to a lesser extent. This differential cellular partitioning of estrogen receptor alpha and beta forms may contribute to the known diversity of 17beta-estradiol effects in target organs. Both estrogen receptor alpha and beta expression levels and cellular localization patterns among tissues, add complexity to the whole estrogen signaling system, in which membrane and mitochondrial events could also be implicated.
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Affiliation(s)
- P Monje
- Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur, Bahía Blanca, Argentina
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Durand S, Dumur C, Flury A, Abadie P, Patrito L, Podhajcer O, Genti-Raimondi S. Altered mitochondrial gene expression in human gestational trophoblastic diseases. Placenta 2001; 22:220-6. [PMID: 11170827 DOI: 10.1053/plac.2000.0601] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
To assess the molecular basis of phenotypic alterations present in the gestational trophoblastic diseases (GTDs) and to identify genes whose expression is specifically associated with these placental proliferative disorders we performed differential display (DD) techniques. This strategy resulted in the isolation of four mitochondrial transcripts downregulated in benign, as well as in malignant, trophoblastic diseases encoding the cytochrome oxidase subunit I (COX I), the ATPase subunit 6, the 12S ribosomal RNA (12S rRNA) and the transfer RNA for phenylalanine (tRNA(Phe)). This expression pattern was confirmed by Northern blot in normal early placenta (NEP), complete hydatidiform mole (CHM), persistent gestational trophoblastic disease (PGTD) and the human choriocarcinoma derived cell line JEG-3. Quantification of mitochondrial DNA by dot blot indicated that these changes in expression were not associated with a significant alteration in the number of mitochondrial genome. In addition, a reduction in the mitochondrial transcription factor A (mtTFA) mRNA level was observed in benign as well as in malignant trophoblastic diseases in correlation with the decrease in the mitochondrial transcript levels. Furthermore, Western blot analysis for COX-I showed a close parallelism with the expression level of the cognate RNA. Taken together, these data demonstrate that a significant change in mitochondrial transcription is associated with the phenotypic alteration present in GTDs.
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MESH Headings
- Adenosine Triphosphatases/genetics
- Base Sequence
- Blotting, Northern
- Blotting, Western
- Choriocarcinoma/genetics
- Cloning, Molecular
- DNA, Mitochondrial/chemistry
- DNA, Mitochondrial/genetics
- Electron Transport Complex IV/genetics
- Female
- Gene Expression
- Humans
- Hydatidiform Mole/genetics
- Isoenzymes
- Membrane Proteins
- Molecular Sequence Data
- Pregnancy
- Prostaglandin-Endoperoxide Synthases
- RNA, Messenger/analysis
- RNA, Transfer, Phe/genetics
- Sequence Analysis, DNA
- Sequence Homology
- Trophoblastic Neoplasms/genetics
- Tumor Cells, Cultured
- Uterine Neoplasms/genetics
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Affiliation(s)
- S Durand
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Pabellón Argentina, Ala Oeste, Ciudad Universitaria, 5000 Córdoba, Argentina
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Chen J, Gokhale M, Schofield B, Odwin S, Yager JD. Inhibition of TGF-β-induced apoptosis by ethinyl estradiol in cultured, precision cut rat liver slices and hepatocytes. Carcinogenesis 2000. [DOI: 10.1093/carcin/21.6.1205] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Li SR, Gyselman VG, Lalude O, Dorudi S, Bustin SA. Transcription of the inositol polyphosphate 1-phosphatase gene (INPP1) is upregulated in human colorectal cancer. Mol Carcinog 2000; 27:322-9. [PMID: 10747296 DOI: 10.1002/(sici)1098-2744(200004)27:4<322::aid-mc10>3.0.co;2-c] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
We have used suppression subtractive hybridization to demonstrate significant overexpression of the inositol polyphosphate 1-phosphatase gene (INPP1) in colorectal cancer compared with matched normal colon epithelium. Its gene product catalyses the hydrolysis of inositol 1,3,4-trisphosphate and inositol 1, 4-bisphosphate, a key molecule in the phosphoinositide metabolic and signaling pathways. Following confirmation of the differential expression by reverse Northern dot blot analysis, fully quantitative Taqman reverse transcriptase-polymerase chain reaction assays showed that its transcription was upregulated in 42/49 colorectal tumors. There was no significant difference in four tumors and reduced transcription was observed in three. This is the first study to report the upregulation of the INPP1 gene in a human cancer and should facilitate further studies looking at the role of phosphatidylinositol signaling reactions in human colorectal cancer.
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Affiliation(s)
- S R Li
- Academic Department of Surgery, St Bartholomew's and the Royal London School of Medicine and Dentistry, London, UK
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de Heredia ML, Izquierdo JM, Cuezva JM. A conserved mechanism for controlling the translation of beta-F1-ATPase mRNA between the fetal liver and cancer cells. J Biol Chem 2000; 275:7430-7. [PMID: 10702318 DOI: 10.1074/jbc.275.10.7430] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
To characterize the mechanisms governing the biogenesis of mitochondria in cancer, we studied the mitochondrial phenotype and the mechanisms controlling the expression of the beta subunit of the mitochondrial H(+)-ATP synthase (beta-F1-ATPase) gene in the rat FAO and AS30D hepatomas. When compared with normal adult rat liver, the relative cellular content of the mitochondrial beta-F1-ATPase and glutamate dehydrogenase, as well as of mitochondrial DNA, was severely reduced in both cell lines. A paradoxical increase in the cellular abundance of beta-F1-ATPase mRNA was observed in cancer cells. Run-on transcription assays and the estimation of mRNA half-lives revealed that the increased abundance of beta-F1-ATPase mRNA results from the stabilization of the transcript in cancer. In vitro translation assays revealed a specific inhibition of the synthesis of the beta-precursor when translation reactions were carried out in the presence of extracts derived from cancer cells. The inhibitory effect was recapitulated using an RNA chimera that contained the 3'-untranslated region of beta-F1-ATPase mRNA. Hepatoma extracts also contained an increased activity of the developmentally regulated translation-inhibitory proteins that bind the 3'-untranslated region of beta-F1-ATPase mRNA. The results indicate that the expression of this gene in hepatoma cells is controlled by the same mechanisms that regulate its expression in the liver during fetal development.
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Affiliation(s)
- M L de Heredia
- Departamento de Biología Molecular, Centro de Biología Molecular "Severo Ochoa," Universidad Autónoma de Madrid, 28049 Madrid, Spain
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Schmitt AO, Specht T, Beckmann G, Dahl E, Pilarsky CP, Hinzmann B, Rosenthal A. Exhaustive mining of EST libraries for genes differentially expressed in normal and tumour tissues. Nucleic Acids Res 1999; 27:4251-60. [PMID: 10518618 PMCID: PMC148701 DOI: 10.1093/nar/27.21.4251] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
A four-step procedure for the efficient and systematic mining of whole EST libraries for differentially expressed genes is presented. After eliminating redundant entries from the EST library under investigation (step 1), contigs of maximal length are built upon each remaining EST using about 4 000 000 public and proprietary ESTs (step 2). These putative genes are compared against a database comprising ESTs from 16 different tissues (both normal and tumour affected) to determine whether or not they are differentially expressed (step 3; electronic northern). Fisher's exact test is used to assess the significance of differential expression. In step 4, an attempt is made to characterise the contigs obtained in the assembly through database comparison. A case study of the CGAP library NCI_CGAP_Br1.1, a library made from three (well, moderately, and poorly differentiated) invasive ductal breast tumours (2126 ESTs in total) was carried out. Of the maximal contigs, 139 were found to be significantly (alpha = 0.05) over-expressed in breast tumour tissue, while 13 appeared to be down-regulated.
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MESH Headings
- Animals
- Blotting, Northern/methods
- Breast Neoplasms/genetics
- Breast Neoplasms/pathology
- Carcinoma, Ductal, Breast/genetics
- Carcinoma, Ductal, Breast/pathology
- Computational Biology
- Databases, Factual
- Down-Regulation
- Expressed Sequence Tags
- Gene Expression Regulation, Neoplastic
- Genes, Neoplasm/genetics
- Humans
- Mitochondria/genetics
- Neoplasm Invasiveness
- RNA, Messenger/analysis
- RNA, Messenger/genetics
- Reproducibility of Results
- Ribosomes/genetics
- Sequence Homology, Nucleic Acid
- Software
- Statistics as Topic
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Affiliation(s)
- A O Schmitt
- metaGen Gesellschaft für Genomforschung mbH, Ihnestrasse 63, D-14195 Berlin, Germany.
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