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1.
J Intellect Disabil Res ; 67(11): 1150-1160, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37671733

RESUMO

BACKGROUND: Sleep-disordered breathing (SDB) is highly prevalent in individuals with Down syndrome (DS), who cease growing earlier than individuals without DS. These characteristics may be associated with increased obesity and subsequent SDB signs, such as snoring and apnoea or excessive daytime sleepiness (EDS). Thus, we assessed the influence of growth on the association between obesity and SDB signs or EDS; we used questionnaires sent to young individuals with DS and their caregivers, in a cross-sectional study. METHODS: We sent out 2000 questionnaires to individuals with DS and their caregivers. The surveys included questions about SDB signs (witnessed snoring or apnoea), subjective sleeping time including witnessed midnight arousal, the Epworth sleepiness scale and witnessed napping as well as sex, age, body weight and body height. RESULTS: Of the 1222 questionnaires we received, 660 were from young individuals and were included in the analysis. SDB signs were highly prevalent (77.1%), and frequency of SDB signs increased with growth (P-trend: P = 0.02) in individuals with DS. Multivariate analyses showed that EDS (Epworth sleepiness scale > 10 points) was associated with body mass index Z-score (Z-BMI) in the 6-9 years age group (odds ratio [OR] 95% confidence interval [95% CI]: 1.69 [1.09-2.62], P = 0.02). Conversely, SDB signs were associated with Z-BMI in the 13-15 (OR [95% CI]: 1.99 [1.06-3.72], P = 0.03) and 16-18 years age groups (OR [95% CI]: 3.04 [1.22-7.59], P = 0.02). For the 19-21 years age group, SDB signs were associated with only male sex (OR [95% CI]: 7.28 [1.22-43.38], P = 0.03). CONCLUSIONS: This study showed that the association between Z-BMI and SDB or EDS was age dependent. In early school-age children with DS, high Z-BMI could not accurately predict the presence of SDB, but it was associated with EDS. In the pubescent period (i.e. 13-18 years), high Z-BMI was associated with SDB signs but not with EDS. Overall, obesity affected SDB signs and EDS differently based on age in young individuals with DS.

2.
Phys Rev Lett ; 124(10): 101102, 2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32216401

RESUMO

In recent years, many γ-ray sources have been identified, yet the unresolved component hosts valuable information on the faintest emission. In order to extract it, a cross-correlation with gravitational tracers of matter in the Universe has been shown to be a promising tool. We report here the first identification of a cross-correlation signal between γ rays and the distribution of mass in the Universe probed by weak gravitational lensing. We use data from the Dark Energy Survey Y1 weak lensing data and the Fermi Large Area Telescope 9-yr γ-ray data, obtaining a signal-to-noise ratio of 5.3. The signal is mostly localized at small angular scales and high γ-ray energies, with a hint of correlation at extended separation. Blazar emission is likely the origin of the small-scale effect. We investigate implications of the large-scale component in terms of astrophysical sources and particle dark matter emission.

3.
Cancer Lett ; 428: 12-20, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29702197

RESUMO

The detection of recurrent mutations affecting the hormone binding domain (HBD) of estrogen receptor alpha (ERα/ESR1) in endocrine therapy-resistant and metastatic breast cancers has prompted interest in functional characterization of these genetic alterations. Here, we explored the role of HBD-ESR1 mutations in influencing the behavior of breast cancer stem cells (BCSCs), using various BC cell lines stably expressing wild-type or mutant (Y537 N, Y537S, D538G) ERα. Compared to WT-ERα clones, mutant cells showed increased CD44+/CD24- ratio, mRNA levels of stemness genes, Mammosphere Forming Efficiency (MFE), Self-Renewal and migratory capabilities. Mutant clones exhibited high expression of NOTCH receptors/ligands/target genes and blockade of NOTCH signaling reduced MFE and migratory potential. Mutant BCSC activity was dependent on ERα phosphorylation at serine 118, since its inhibition decreased MFE and NOTCH4 activation only in mutant cells. Collectively, we demonstrate that the expression of HBD-ESR1 mutations may drive BC cells to acquire stem cell traits through ER/NOTCH4 interplay. We propose the early detection of HBD-ESR1 mutations as a challenge in precision medicine strategy, suggesting the development of tailored-approaches (i.e. NOTCH inhibitors) to prevent disease development and metastatic spread in BC mutant-positive patients.


Assuntos
Neoplasias da Mama/genética , Receptor alfa de Estrogênio/genética , Células-Tronco Neoplásicas/patologia , Receptor Notch4/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Receptor alfa de Estrogênio/metabolismo , Feminino , Testes Genéticos , Humanos , Células MCF-7 , Mutação , Fosforilação , Medicina de Precisão/métodos , Domínios Proteicos/genética , Receptor Notch4/antagonistas & inibidores , Serina/metabolismo , Esferoides Celulares
5.
J Biol Regul Homeost Agents ; 32(4 Suppl. 1): 1-7. 4° JOINT MEETING OF PATHOLOGY AND LABORATORY MEDICINE SIPMET­SIPMEL - SECOND JOINT MEETING IN COLLABORATION WITH ASIP­AMP­UEMS­WASPALM - 4° SIPMEL NATIONAL CONGRESS - 34° SIPMET NATIONAL CONGRESS - 4° CONGRESS OF PATHOLOGY AND LABORATORY MEDICINE, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30761858
6.
Epidemiol Psychiatr Sci ; 27(2): 199-208, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-27989255

RESUMO

AIMS: Public stigma alters attitudes towards people with mental illness, and is a particular concern for young people since most mental health problems occur in adolescence and young adulthood. However, little is known about the long-term effects of repeated filmed social contact (FSC) on reducing mental health-related stigma among young adults in the general population, compared with self-instructional Internet search (INS) and control interventions. METHODS: This study is a parallel-group randomised controlled trial over 12 months conducted in Tokyo, Japan. A total of 259 university students (male n = 150, mean age = 20.0 years, s.d. = 1.2) were recruited from 20 colleges and universities between November 2013 and July 2014, without being provided information about the mental health-related survey or trial. Participants were assigned to one of three groups before completion of the baseline survey (FSC/INS/control = 89/83/87). The FSC group received a computer-based 30-min social contact film with general mental health education and five follow-up web-based FSCs at 2-month intervals. The INS group undertook a 30-min search for mental health-related information with five follow-up web-based reminders for self-instructional searches at 2-month intervals. The control group played PC games and had no follow-up intervention. The main outcome measures were the future (intended behaviour) domain of the Reported and Intended Behaviour Scale at 12 months after the intervention. Analysis was conducted in September 2015. RESULTS: At the 12-month follow-up, 218 participants completed the survey (84.1%, 75:70:73). The FSC group showed the greatest change at the 12-month follow-up (FSC: mean change 2.11 [95% CI 1.49, 2.73], INS: 1.04 [0.29, 1.80], control: 0.71 [0.09, 1.33]; FSC v. INS p = 0.037, FSC v. controls p = 0.004). No adverse events were reported during the follow-up period. CONCLUSIONS: FSC was more successful in reducing stigma at 12 months after intervention than INS or control interventions. FSC could be used to reduce stigma in educational lectures and anti-stigma campaigns targeted at young people. STUDY REGISTRATION: This study is registered at UMIN-CTR (No. UMIN000012239).


Assuntos
Educação em Saúde/métodos , Conhecimentos, Atitudes e Prática em Saúde , Meios de Comunicação de Massa , Transtornos Mentais/psicologia , Discriminação Social , Estigma Social , Adolescente , Adulto , Feminino , Humanos , Japão , Avaliação de Processos e Resultados em Cuidados de Saúde , Inquéritos e Questionários , Adulto Jovem
7.
Oncogene ; 36(46): 6420-6431, 2017 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-28745321

RESUMO

Appropriate 'in vivo' models are crucial for studying breast cancer biology and evaluating the efficacy of therapeutic agents. Thus we engineered a novel transgenic mouse line expressing the human Ki-Ras bearing an activating mutation (Ki-Ras(G12V)) selectively in the mammary epithelium after lactation. These mice develop invasive ductal adenocarcinomas with 100% incidence within 3-9 months after Ki-Ras(G12V) induction. Immunophenotyping revealed that the mammary tumors express luminal markers, are positive for estrogen and progesterone receptors, negative for HER2 and have a low proliferation index. Moreover, cell lines derived from such tumors are estrogen-responsive and, when transplanted into nude mice, form tumors that respond to the antiestrogen ICI 182780. In conclusion, the mammary tumors of these transgenic mice and the derived cell lines exhibit key features of the major form of human breast cancer, that is, luminal A subtype and thus have a high potential for breast cancer research and treatment.


Assuntos
Adenocarcinoma/genética , Epitélio/metabolismo , Receptor alfa de Estrogênio/genética , Genes ras/genética , Glândulas Mamárias Animais/metabolismo , Neoplasias Mamárias Experimentais/genética , Adenocarcinoma/metabolismo , Animais , Estradiol/análogos & derivados , Estradiol/farmacologia , Antagonistas do Receptor de Estrogênio/farmacologia , Receptor alfa de Estrogênio/metabolismo , Feminino , Fulvestranto , Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Células MCF-7 , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias Mamárias Experimentais/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Nus , Camundongos Transgênicos , Mutação de Sentido Incorreto , Células Tumorais Cultivadas
8.
J Intellect Disabil Res ; 61(7): 656-667, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28378398

RESUMO

BACKGROUND: People with Down syndrome (DS) often have sleep-disordered breathing (SDB). Unusual sleep postures, such as leaning forward and sitting, are observed in people with DS. This study aimed to clarify the prevalence of unusual sleep postures and their relationships with SDB-related symptoms (SDB-RSs), such as snoring, witnessed apnoea, nocturnal awakening and excessive daytime sleepiness. METHODS: A questionnaire, including demographic characteristics and the presence of unusual sleep postures, as well as SDB-RSs, was completed by 1149 parents of people with DS from Japan. RESULTS: Unusual sleep postures were recorded in 483 (42.0%) people with DS. These participants were significantly younger and had a history of low muscle tone more frequently than people without unusual sleep postures. In all ages, the leaning forward posture was more frequent than sitting. People with DS with unusual sleep postures suffered from SDB-RSs. Those who slept in the sitting posture had more frequent SDB-RSs than did those who slept with the leaning forward posture. Snoring, witnessed apnoea and nocturnal awakening were observed in 73.6, 27.2 and 58.2% of participants, respectively. Snoring increased with aging. Witnessed apnoea was more common in males and in those with hypothyroidism than in females and in those without hypothyroidism. CONCLUSIONS: Our study shows that there is a close relationship between unusual sleep postures and SDB-RSs. We recommend that all people with DS with unusual sleep postures should be checked for the presence of SDB.


Assuntos
Distúrbios do Sono por Sonolência Excessiva/fisiopatologia , Síndrome de Down/fisiopatologia , Postura/fisiologia , Síndromes da Apneia do Sono/fisiopatologia , Distúrbios do Início e da Manutenção do Sono/fisiopatologia , Ronco/fisiopatologia , Adolescente , Adulto , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Adulto Jovem
9.
J Endocrinol Invest ; 39(6): 695-708, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27037688

RESUMO

PURPOSE: Management of late onset hypogonadism (LOH) is not homogenous. The aim of the study is to observe the management of patients with low testosterone (T) in highly specialized Italian centres. METHODS: The SIAMO-NOI is an observational longitudinal disease registry for the evaluation of the clinical management of patients with low T levels (total T < 12 nmol/L, calculated free T < 225 pmol/l or already in treatment) in 15 Italian centers members of the Italian Society for Andrology and Sexual Medicine (SIAMS). Clinical and biochemical data were collected for four visits during 12 months of observation. RESULTS: 432 patients (mean age 50.9 ± 14.9 years) were enrolled. Of them, 247 men were receiving androgen therapy, whereas 145 were naive. After the first visit (V0), 80 men started androgen therapy, whereas 55 remained untreated during the entire observation. Younger age [odds ratio (OR) 0.57 (0.35-0.92)], total T < 8 nmol/l [OR 4.69 (1.59-13.81)], complaining at least one sexual symptom [OR 11.55 (2.01-66.35)] and reporting more severe lower urinary tract symptoms [OR 1.27 (1.01-1.60)] predicted starting an androgen therapy. Sixty-four men started therapy immediately after V0 and maintained it until the observation end. When compared to V0, they reported an increase in all the domains of the International Index of Erectile Function-15 (IIEF-15), in the sexual and physical subdomains of the Aging Male Scale as well as in the International Prostate Symptom Score. Conversely, the untreated group reported a significant improvement, although lower than the treated group, only in the erectile function domain of the IIEF-15. CONCLUSIONS: Management of LOH in SIAMS centres is in line with the international guidelines and the newest knowledge about the role of T on prostate health. Androgen therapy is associated with an improvement in all the aspects of sexual life and in the perception of physical strength.


Assuntos
Androgênios/efeitos adversos , Disfunção Erétil/induzido quimicamente , Terapia de Reposição Hormonal/efeitos adversos , Hipogonadismo/tratamento farmacológico , Testosterona/efeitos adversos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Inquéritos e Questionários
10.
Rev Sci Instrum ; 87(2): 02B921, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26932093

RESUMO

Francium is the heaviest species among the alkali elements. Due to its properties, francium is said to be of advantage in measurements of tiny observations, such as atomic parity violation and electric dipole moment. Before executing experiments with francium, it must be produced artificially because it is one of the most unstable elements. We produced francium with the nuclear fusion reaction of an oxygen beam and gold target, ionized the produced francium through a thermal ionization process, and extracted the ion with electrostatic fields. However, the thermal ionization process is known to ionize not only an objective atom but also other atomic species. Therefore, a Wien filter was installed to analyze the composition of the ion beam and purify the beam. This allowed us to improve the beam purity from ∼10(-6) to ∼10(-3).

11.
Breast Cancer Res Treat ; 156(2): 409, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27008182

RESUMO

Erratum to: Breast Cancer Res Treat (2012), 134:569­581, DOI 10.1007/s10549-012-2090-9. Uunfortunately, authors could not find the original film from which the figure was drawn. Therefore, as suggested by the Editor, they have repeated the relative experiment, and ask to publish this new figure as a correction. The authors apologize for any inconvenience that it may cause.

12.
Appl Opt ; 55(5): 1164-9, 2016 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-26906392

RESUMO

We demonstrate frequency offset locking between two laser sources using a waveguide-type electro-optic modulator (EOM) with 10th-order sidebands for magneto-optical trapping of Fr atoms. The frequency locking error signal was successfully obtained by performing delayed self-homodyne detection of the beat signal between the repumping frequency and the 10th-order sideband component of the trapping light. Sweeping the trapping-light and repumping-light frequencies with keeping its frequency difference of 46 GHz was confirmed over 1 GHz by monitoring the Doppler absorption profile of I2. This technique enables us to search for a resonance frequency of magneto-optical trapping of Fr.

13.
SSM Popul Health ; 2: 807-812, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29349191

RESUMO

AIMS: Many studies have shown that natural disasters affect mental health; however, longitudinal data on post-disaster mental health problems are scarce. The aims of our study were to investigate the trend in psychological distress and alcoholism after The Great East Japan Earthquake and tsunami in north eastern Japan, in March 2011. METHODS: A longitudinal study was conducted using annual health check data for the general population, in the city of Higashi-Matsushima, which was affected by the high impact of tsunami. In 2012 and 2013, the Kessler Psychological Distress Scale and the CAGE questionnaire (for screening for alcoholism) were used to assess psychological distress and prevalence of alcoholism. RESULTS: Of 11,855 total eligible residents, 2192 received the annual check in 2012 and 2013. The prevalence of mental illness and the mean score of alcoholism tendency increased during the follow-up period. The majority of respondents (43.8%) with baseline serious mental illness (SMI) continued to have SMI at follow-up; only 16.7% reported recovering. Older age, female sex, and severity of home damage predicted higher psychological distress, while male sex was a risk factor for alcoholism at follow-up. CONCLUSIONS: Psychological distress deteriorated 2 years after the huge natural disaster, compared with 1 year after the disaster. Long-term mental health care is needed for those affected by natural disasters, particularly those who have suffered loss.

14.
Mini Rev Med Chem ; 16(8): 651-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26156550

RESUMO

Hydrogels have received growing attention as materials for drug delivery systems (DDS) because of their biodegradable and biocompatible properties. DDS were developed to optimize the therapeutic properties of drug products and to render them more safe, effective, and reliable. In the past, drugs were frequently administered orally, as liquids or in powder forms. To avoid problems incurred through the utilization of the oral route of administration, new dosage forms, DDS, containing the drugs were introduced. They can deliver drugs directly to the intended site of action and can also improve treatment efficacy, while minimizing unwanted side effects elsewhere in the body, which often limit the long-term use of many drugs, and provide better efficacy of treatment. Biocompatible hydrogels are an example of such systems available for therapeutic use. In this review, results from recent publications concerning these systems are discussed. Hydrogels show superior effectiveness over conventional methods of treatment providing controlled release of active substances. They are of interest in medical applications such as breast cancer treatment.


Assuntos
Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico , Materiais Biocompatíveis/administração & dosagem , Materiais Biocompatíveis/química , Neoplasias da Mama/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Hidrogéis/administração & dosagem , Hidrogéis/química , Humanos
15.
Phys Rev Lett ; 113(10): 102501, 2014 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-25238351

RESUMO

The direct 3α decay branch from the 02+ state at Ex=7.65 MeV in 12C, which is known as the Hoyle state, is considered to affect the triple-α reaction rate strongly and to give crucial information on its structure. We have performed a high-precision measurement of the 3α decay from this state using the 12C(12C,3α)12C reaction at E12C=110 MeV. The branching ratio of the direct 3α decay was under the detection limit in the present experiment. By comparing with Monte Carlo simulations for three decay mechanisms as the sequential decay through the ground state of ^{8}Be, the direct decay with equal energies of three α particles, and the direct decay to the phase space uniformly, we have obtained the upper limit of 0.2% on the direct 3α decay.

16.
Insect Mol Biol ; 23(4): 466-74, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24698498

RESUMO

Salp16, a 16-kDa tick salivary gland protein, is known to be the molecule involved in the transmission of Anaplasma phagocytophilum, an obligate intracellular pathogen causing zoonotic anaplasmosis, from its mammalian hosts to Ixodes scapularis. Recently, the presence of A. phagocytophilum was documented in Japan and Ixodes persulcatus was identified as one of its vectors. The purpose of this study was to identify Salp16 genes in I. persulcatus and characterize their function. Two cDNA clones encoding the Salp16-like sequences were obtained from the salivary glands of fed female I. persulcatus ticks and designated Salp16 Iper1 and Iper2. Gene expression analyses showed that the Salp16 Iper genes were expressed specifically in the salivary glands and were up-regulated by blood feeding. These proteins attenuated the oxidative burst of activated bovine neutrophils and inhibited their migration induced by the chemoattractant interleukin-8 (IL-8). These results demonstrate that Salp16 Iper proteins contribute to the establishment of blood feeding as an immunosuppressant of neutrophil, an essential factor in innate host immunity. Further examination of the role of Salp16 Iper in the transmission of pathogens, including A. phagocytophilum, will increase our understanding of the tick-host-pathogen interface.


Assuntos
Anaplasma phagocytophilum/crescimento & desenvolvimento , Anaplasmose/transmissão , Ixodes/imunologia , Ixodes/microbiologia , Neutrófilos/imunologia , Neutrófilos/microbiologia , Glândulas Salivares/metabolismo , Proteínas e Peptídeos Salivares/genética , Sequência de Aminoácidos , Anaplasmose/imunologia , Animais , Vetores Artrópodes , Sequência de Bases , Bovinos/imunologia , DNA Complementar , Feminino , Dados de Sequência Molecular , Glândulas Salivares/microbiologia , Proteínas e Peptídeos Salivares/metabolismo
17.
Rev Sci Instrum ; 85(2): 02A732, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24593466

RESUMO

The search for the violation of the fundamental symmetry in a radioactive atom is the promising candidate for precision tests of the standard model and its possible extensions. The subtle signal arising from the symmetry violation is enhanced in heavy atoms, such as a francium (Fr). To realize high precision measurements, a large amount of radioactive isotopes is required. The Fr is produced via a nuclear fusion reaction using a melted gold target with a (18)O primary beam at Cyclotron and Radioisotope Center, Tohoku University. The maximum extraction efficiency of the Fr ion was achieved at approximately 35%. The beam line consists of an electrostatic deflector, three electrostatic quadrupole triplets to the measurement area at 10 m away from the reaction point, and several beam diagnosis systems. We optimized parameters of the beam line.

19.
Cell Death Dis ; 4: e747, 2013 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-23907461

RESUMO

We have previously shown that estrogens binding to estrogen receptor (ER) α increase proliferation of Leydig tumor cells. Estrogens can also bind to G protein-coupled ER (GPER) and activation of this receptor can either increase or decrease cell proliferation of several tumor types. The aim of this study was to investigate GPER expression in R2C rat tumor Leydig cells, evaluate effects of its activation on Leydig tumor cell proliferation and define the molecular mechanisms triggered in response to its activation. R2C cells express GPER and its activation, using the specific ligand G-1, is associated with decreased cell proliferation and initiation of apoptosis. Apoptosis after G-1 treatment was asserted by appearance of DNA condensation and fragmentation, decrease in Bcl-2 and increase in Bax expression, cytochrome c release, caspase and poly (ADP-ribose) polymerase-1 (PARP-1) activation. These effects were dependent on GPER activation because after silencing of the gene, using a specific small interfering RNA, cyt c release, PARP-1 activation and decrease in cell proliferation were abrogated. These events required a rapid, however, sustained extracellular regulated kinase 1/2 activation. G-1 was able to decrease the growth of R2C xenograft tumors in CD1 nude mice while increasing the number of apoptotic cells. In addition, in vivo administration of G-1 to male CD1 mice did not cause any alteration in testicular morphology, while cisplatin, the cytotoxic drug currently used for the therapy of Leydig tumors, severely damaged testicular structure, an event associated with infertility in cisplatin-treated patients. These observations indicate that GPER targeting for the therapy of Leydig cell tumor may represent a good alternative to cisplatin to preserve fertility in Leydig tumor patients.


Assuntos
Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Tumor de Células de Leydig/tratamento farmacológico , Receptores Acoplados a Proteínas G/metabolismo , Neoplasias Testiculares/tratamento farmacológico , Animais , Antineoplásicos Hormonais/farmacologia , Linhagem Celular Tumoral , Forma do Núcleo Celular/efeitos dos fármacos , Ciclopentanos/farmacologia , Dano ao DNA , Estradiol/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Expressão Gênica , Tumor de Células de Leydig/patologia , Sistema de Sinalização das MAP Quinases , Masculino , Camundongos , Camundongos Nus , Quinolinas/farmacologia , Ratos , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/genética , Neoplasias Testiculares/patologia , Testículo/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Cell Death Dis ; 4: e724, 2013 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-23846226

RESUMO

Sexual hormones, estrogens and androgens, determine biological response in a tissue- and gender-specific manner and have a pivotal role in endocrine-mediated tumorigenesis. In situ estrogen production by aromatase is a critical determinant for breast cancer growth and progression. On the contrary, clinical and in vitro studies indicate that androgens have a protective role in mammary carcinogenesis. Here, we demonstrated, in hormone-dependent breast cancer cells, the existence of a functional interplay between the androgen receptor (AR), the orphan nuclear receptor DAX-1 and the aromatase enzyme involved in the inhibition of the estrogen-dependent breast cancer cell proliferation exerted by androgen signaling. Indeed, our results revealed, in MCF-7 cells, that ligand-activated AR induces the expression of the orphan nuclear receptor DAX-1 by direct binding to a newly identified androgen-response-element within the DAX-1 proximal promoter. In turn, androgen-induced DAX-1 is recruited, in association with the corepressor N-CoR, within the SF-1/LRH-1 containing region of the aromatase promoter, thereby repressing aromatase expression and activity. In elucidating a novel mechanism by which androgens, through DAX-1, inhibit aromatase expression in breast cancer cell lines, these findings reinforce the theory of androgen- opposing estrogen-action, opening new avenues for therapeutic intervention in estrogen-dependent breast tumors.


Assuntos
Aromatase/metabolismo , Proliferação de Células , Receptor Nuclear Órfão DAX-1/genética , Estrogênios/fisiologia , Androgênios/farmacologia , Apoptose , Aromatase/genética , Sequência de Bases , Neoplasias da Mama , Receptor Nuclear Órfão DAX-1/metabolismo , Repressão Enzimática , Feminino , Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Células MCF-7 , Nandrolona/análogos & derivados , Nandrolona/farmacologia , Neoplasias Hormônio-Dependentes , Regiões Promotoras Genéticas , Receptores Androgênicos/metabolismo , Elementos de Resposta
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