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1.
Food Chem Toxicol ; 175: 113711, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36893891

RESUMO

As a promiscuous xenobiotic receptor, pregnane X receptor (PXR) has been confirmed to participate in numerous physiological process. In addition to the conventional estrogen/androgen receptor, PXR also serves as an alternative target for environmental chemical contaminants. In this work, the PXR-mediated endocrine disrupting effects of typical food contaminants were explored. Firstly, the time-resolved fluorescence resonance energy transfer assays confirmed the PXR binding affinities of 2,2',4,4',5,5'-hexachlorobiphenyl, bis(2-ethylhexyl) phthalate, dibutyl phthalate, chlorpyrifos, bisphenol A, and zearalenone, with IC50 values ranging from 1.88 to 4284.00 nM. Then their PXR agonist activities were assessed by PXR-mediated CYP3A4 reporter gene assays. Subsequently, the regulation of gene expressions of PXR and its targets CYP3A4, UGT1A1, and MDR1 by these compounds was further investigated. Intriguingly, all the tested compounds interfered with these gene expressions, confirming their endocrine disrupting effects via PXR-mediated signaling. The compound-PXR-LBD binding interactions were explored by molecular docking and molecular dynamics simulations to unravel the structural basis of their PXR binding capacities. The weak intermolecular interactions are key players in stabilizing these compound-PXR-LBD complexes. During the simulation process, 2,2',4,4',5,5'-hexachlorobiphenyl remained stable while the other 5 compounds underwent relatively severe disturbances. In conclusion, these food contaminants might exhibit endocrine disrupting effects via PXR.


Assuntos
Receptores de Esteroides , Receptor de Pregnano X , Receptores de Esteroides/genética , Receptores de Esteroides/metabolismo , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/metabolismo , Simulação de Acoplamento Molecular
2.
Virchows Arch ; 482(2): 339-345, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36469101

RESUMO

Acinic cell carcinoma (AciCC) is a common salivary gland malignancy, typically composed of neoplastic acinic cells with zymogen granules. The vast majority of cases are driven by a t(4;9)(q13;q31) leading to enhancer hijacking and upregulation of the NR4A3 gene. However, a minority of cases do not display NR4A3 overexpression on immunohistochemical examination and are negative for the rearrangement involving the NR4A3 gene when tested by FISH. Such cases overexpress NR4A2, and the protein product is detectable by immunohistochemistry. In this study, we aimed to assess the utility of NR4A2 and NR4A3 immunohistochemistry in the differential diagnosis of salivary gland tumors. Eighty-five cases of classic low-grade ACiCC, as well as 36 cases with high-grade transformation (HGT) and 7 high-grade AciCC cases were included in the analysis. NR4A3 was at least focally positive in 105/128 (82%) cases. Out of the 23 cases that were immunohistochemically negative for NR4A3, 6 displayed nuclear immunopositivity with the NR4A2 antibody. The NR4A3 rearrangement was confirmed by FISH in 38/52 (73%) cases. In addition, this is the first report of an NR4A2 rearrangement being detected by FISH in 2 AciCC cases that were negative for the NR4A3 rearrangement. Our analysis confirms that the majority of AciCC, including high-grade cases and cases with HGT, are immunopositive for NR4A3, and suggests that NR4A3 immunohistochemistry is a powerful tool in the differential diagnosis of salivary gland tumors. However, its utility is limited in sub-optimally fixed samples which often display weaker and focal positivity. Our study also indicates that in a minority of cases, AciCC might be negative for NR4A3 immunostaining, because the pathogenic genetic event in these cases is instead a rearrangement involving the NR4A2 gene.


Assuntos
Carcinoma de Células Acinares , Receptores de Esteroides , Neoplasias das Glândulas Salivares , Humanos , Carcinoma de Células Acinares/diagnóstico , Carcinoma de Células Acinares/genética , Carcinoma de Células Acinares/metabolismo , Glândulas Salivares/patologia , Neoplasias das Glândulas Salivares/diagnóstico , Neoplasias das Glândulas Salivares/genética , Neoplasias das Glândulas Salivares/patologia , Núcleo Celular/patologia , Imuno-Histoquímica , Biomarcadores Tumorais/análise , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Proteínas de Ligação a DNA/metabolismo , Receptores de Esteroides/genética , Receptores dos Hormônios Tireóideos/metabolismo
3.
Drug Metab Dispos ; 51(3): 276-284, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36460477

RESUMO

Reliable in vitro to in vivo translation of cytochrome P450 (CYP) 3A4 induction potential is essential to support risk mitigation for compounds during pharmaceutical discovery and development. In this study, a linear correlation of CYP3A4 mRNA induction potential in human hepatocytes with the respective pregnane-X receptor (PXR) activation in a reporter gene assay using DPX2 cells was successfully demonstrated for 13 clinically used drugs. Based on this correlation, using rifampicin as a positive control, the magnitude of CYP3A4 mRNA induction for 71 internal compounds at several concentrations up to 10 µM (n = 90) was predicted within 2-fold error for 64% of cases with only a few false positives (19%). Furthermore, the in vivo area under the curve reduction of probe CYP substrates was reasonably predicted for eight marketed drugs (carbamazepine, dexamethasone, enzalutamide, nevirapine, phenobarbital, phenytoin, rifampicin, and rufinamide) using the static net effect model using both the PXR activation and CYP3A4 mRNA induction data. The liver exit concentrations were used for the model in place of the inlet concentrations to avoid false positive predictions and the concentration achieving twofold induction (F2) was used to compensate for the lack of full induction kinetics due to cytotoxicity and solubility limitations in vitro. These findings can complement the currently available induction risk mitigation strategy and potentially influence the drug interaction modeling work conducted at clinical stages. SIGNIFICANCE STATEMENT: The established correlation of CYP3A4 mRNA in human hepatocytes to PXR activation provides a clear cut-off to identify a compound showing an in vitro induction risk, complementing current regulatory guidance. Also, the demonstrated in vitro-in vivo translation of induction data strongly supports a clinical development program although limitations remain for drug candidates showing complex disposition pathways, such as involvement of auto-inhibition/induction, active transport and high protein binding.


Assuntos
Citocromo P-450 CYP3A , Receptores de Esteroides , Humanos , Citocromo P-450 CYP3A/metabolismo , Receptor de Pregnano X/metabolismo , Receptores de Esteroides/genética , Receptores de Esteroides/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Rifampina/farmacologia , Rifampina/metabolismo , Indução Enzimática , Hepatócitos/metabolismo , RNA Mensageiro/metabolismo
4.
Curr Med Res Opin ; 36(11): 1825-1833, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32965131

RESUMO

OBJECTIVES: Recognizing the value of anticancer treatments based on progression-free survival and overall survival may help decision making in healthcare policy. We aimed to measure and compare the impact of disease progression and terminal state prior to death on healthcare costs in HR+, HER2- ABC patients. METHODS: We conducted a retrospective study using Korean nationwide health insurance claims database between 1 September 2012 and 31 August 2017. The impact of disease progression was estimated by measuring the average incremental monthly cost per patient during 1 year after progression compared to 1 year before progression. Death-related costs per patient per month (PPPM) were measured for those who died within 1 year after progression. Generalized estimating equation (GEE) was used to estimate the variations in PPPM costs by progression and death with adjustment for clinical factors. RESULTS: After progression, 1,636 patients expensed $2,892 per month more on average than before progression ($3762 vs. $870). The GEE analysis with adjustment for baseline characteristics showed that PPPM costs increased by 3.46 folds (95% CI = 3.06-3.93) after progression. Also, PPPM costs were 1.74 (95%CI = 1.43-2.12) times higher in patients who died within 1 year after progression relative to survived patients. When considering the interaction between progression and death, deceased patients showed higher increased ratio of PPPM costs after progression (4.91; p=value<.0001) than survived patients (2.95; 95% CI = 2.61-3.34). CONCLUSIONS: From the payer's perspective, more healthcare costs incurred during the progression state than terminal state in HR+, HER2- ABC patients. The impact of disease progression emphasizes the importance of effectively treating HR+, HER2- ABC patients.


Assuntos
Neoplasias da Mama/economia , Neoplasias da Mama/terapia , Custos de Cuidados de Saúde/estatística & dados numéricos , Adulto , Idoso , Antineoplásicos/economia , Antineoplásicos/uso terapêutico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/mortalidade , Feminino , Humanos , Seguro Saúde/estatística & dados numéricos , Menopausa , Pessoa de Meia-Idade , Receptor ErbB-2/metabolismo , Receptores de Esteroides/metabolismo , República da Coreia , Estudos Retrospectivos
5.
Reprod Biol Endocrinol ; 17(1): 111, 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31878927

RESUMO

BACKGROUND: Previous studies of expression profiles of major endometrial effectors of steroid physiology in endometriosis have yielded markedly conflicting conclusions, presumably because the relative effects of type of endometriosis, fertility history and menstrual cycle phases on the measured variables were not considered. In the present study, endometrial mRNA and protein levels of several effectors of steroid biosynthesis and action in patients with stage III-IV ovarian endometriosis (OE) with known fertility and menstrual cycle histories were compared with the levels in control endometrium to test this concept. METHODS: Endometrial samples were collected from patients without endometriosis (n = 32) or OE stages III-IV (n = 52) with known fertility and cycle histories. qRT-PCR and immunoblotting experiments were performed to measure levels of NR5A1, STAR, CYP19A1, HSD17Bs, ESRs and PGR transcripts and proteins, respectively. Tissue concentrations of steroids (P4, T, E1 and E2) were measured using ELISAs. RESULTS: The levels of expression of aromatase and ERß were lower (P < 0.0001) and 17ß-HSD1 (P < 0.0001) and PRA (P < 0.01) were higher in OE endometrium. Lower aromatase levels and higher 17ß-HSD1 levels were detected in fertile (aromatase: P < 0.05; 17ß-HSD1: P < 0.0001) and infertile (aromatase: P < 0.0001; 17ß-HSD1: P < 0.0001) OE endometrium than in the matched control tissues. Both proliferative (PP) and secretory (SP) phase OE samples expressed aromatase (P < 0.0001) and ERß (PP: P < 0.001; SP: P < 0.01) at lower levels and 17ß-HSD1 (P < 0.0001) and PRA (PP: P < 0.01; SP: P < 0.0001) at higher levels than matched controls. Higher 17ß-HSD1 (P < 0.01) and E2 (P < 0.05) levels and a lower (P < 0.01) PRB/PRA ratio was observed in infertile secretory phase OE endometrium than in control. CONCLUSIONS: We report that dysregulated expression of 17ß-HSD1 and PGR resulting in hyperestrogenism and progesterone resistance during the secretory phase of the menstrual cycle, rather than an anomaly in aromatase expression, was the hallmark of eutopic endometrium from infertile OE patients. Furthermore, the results provide proof of concept that the fertility and menstrual cycle histories exerted relatively different effects on steroid physiology in the endometrium from OE patients compared with the control subjects.


Assuntos
Endometriose/metabolismo , Endométrio/metabolismo , Hormônios Esteroides Gonadais/metabolismo , Doenças Ovarianas/metabolismo , Receptores de Esteroides/metabolismo , 17-Hidroxiesteroide Desidrogenases/análise , 17-Hidroxiesteroide Desidrogenases/genética , Adolescente , Adulto , Aromatase/análise , Aromatase/genética , Endométrio/química , Estradiol/análise , Feminino , Expressão Gênica , Humanos , Infertilidade Feminina/metabolismo , Ciclo Menstrual , Progesterona/análise , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Receptores de Esteroides/genética , Adulto Jovem
6.
Biochemistry (Mosc) ; 84(11): 1306-1328, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31760920

RESUMO

Focal brain injuries (in particular, stroke and traumatic brain injury) induce with high probability the development of delayed (months, years) cognitive and depressive disturbances which are frequently comorbid. The association of these complications with hippocampal alterations (in spite of the lack of a primary injury of this structure), as well as the lack of a clear dependence between the probability of depression and dementia development and primary damage severity and localization served as the basis for a new hypothesis on the distant hippocampal damage as a key link in the pathogenesis of cognitive and psychiatric disturbances. According to this hypothesis, the excess of corticosteroids secreted after a focal brain damage, in particular in patients with abnormal stress-response due to hypothalamic-pituitary-adrenal axis (HPAA) dysfunction, interacts with corticosteroid receptors in the hippocampus inducing signaling pathways which stimulate neuroinflammation and subsequent events including disturbances in neurogenesis and hippocampal neurodegeneration. In this article, the molecular and cellular mechanisms associated with the regulatory role of the HPAA and multiple functions of brain corticosteroid receptors in the hippocampus are analyzed. Functional and structural damage to the hippocampus, a brain region selectively vulnerable to external factors and responding to them by increased cytokine secretion, forms the basis for cognitive function disturbances and psychopathology development. This concept is confirmed by our own experimental data, results of other groups and by prospective clinical studies of post-stroke complications. Clinically relevant biochemical approaches to predict the risks and probability of post-stroke/post-trauma cognitive and depressive disturbances are suggested using the evaluation of biochemical markers of patients' individual stress-response. Pathogenetically justified ways for preventing these consequences of focal brain damage are proposed by targeting key molecular mechanisms underlying hippocampal dysfunction.


Assuntos
Lesões Encefálicas/patologia , Hipocampo/metabolismo , Animais , Lesões Encefálicas/metabolismo , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Citocinas/metabolismo , Humanos , Estresse Oxidativo , Sistema Hipófise-Suprarrenal , Receptores de Esteroides/metabolismo
7.
Histol Histopathol ; 34(6): 631-644, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30426467

RESUMO

INTRODUCTION: The morphology of the endometrium constantly changes in the reproductive period, depending on the levels of ovarian steroid hormones, and undergoes atrophic changes during menopause as a result of their insufficiency. The purpose of this study was to analyze morphological and morphometric changes in the mucous and muscle layers of the uterine wall in postmenopausal women, and to assess localization and number of cells showing the expression of steroid hormone receptors, namely estrogen receptor α (ER-α), progesterone receptor (PR), and androgen receptor (AR) in glandular epithelial cells and smooth muscle cells in particular groups of women. MATERIAL AND METHODS: The study material consisted of uterine specimens sectioned across the full thickness of the uterine wall, and embedded in 164 paraffin blocks. The specimens came from women without menopausal hormone therapy (MHT) operated due to reproductive organ prolapse or uterine myomas. The material was divided into four groups depending on the time interval from menopause to surgery: group I - from 1 to 5 years after menopause, group II - from 6 to 10 years after menopause, group III - more than 11 years after menopause, and group IV - women over 70 years of age. The sections were stained by standard HE, Masson's trichrome, and immunohistochemical methods (ERα, PR, AR). Quantitative assessment of the results was based on computer image analysis. RESULTS: Analysis of morphological changes in the endometrium and myometrium revealed the presence of increasing regressive changes, such as various types of atrophy, fibrosis, and calcification, augmented over time from the last menstruation. Furthermore, endometrial polyps, foci of endometriosis, and leiomyomas were observed. Based on the results of morphometric measurements, a constant decrease in the endometrial and myometrial thickness was noticed in the studied groups (I-IV). Significant differences between the groups were observed in the number of ER-α positive cells in the myometrium, but not in the endometrial glandular epithelium. Statistically significant differences in the number of AR positive cells were detected in the endometrial epithelium and in the uterine muscle. The analysis the number of PR positive cells demonstrated differences between the groups in the endometrial stroma and the myometrium. CONCLUSION: The uterus of postmenopausal woman undergo major morphological changes (mainly atrophic lesions in the endometrium and myometrium), leading to a decline in their morphometric parameters over time from the last menstruation. Localization and number of cells showing the expression of steroid receptors: ER-α, PR, and AR in the uterus of postmenopausal women, depending on the time interval from the last menstruation.


Assuntos
Endométrio/metabolismo , Miométrio/metabolismo , Pós-Menopausa , Receptores de Esteroides/metabolismo , Útero/anatomia & histologia , Útero/metabolismo , Idoso , Endometriose/metabolismo , Endométrio/anatomia & histologia , Células Epiteliais/metabolismo , Receptor alfa de Estrogênio/metabolismo , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Leiomioma/metabolismo , Menopausa , Pessoa de Meia-Idade , Miócitos de Músculo Liso/metabolismo , Miométrio/anatomia & histologia , Pólipos/metabolismo , Receptores Androgênicos/metabolismo , Receptores de Progesterona/metabolismo
8.
J Clin Oncol ; 36(1): 14-24, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29035645

RESUMO

Purpose To estimate the contribution of differences in demographics, comorbidity, insurance, tumor characteristics, and treatment to the overall mortality disparity between nonelderly black and white women diagnosed with early-stage breast cancer. Patients and Methods Excess relative risk of all-cause death in black versus white women diagnosed with stage I to III breast cancer, expressed as a percentage and stratified by hormone receptor status for each variable (demographics, comorbidity, insurance, tumor characteristics, and treatment) in sequentially, propensity-scored, optimally matched patients by using multivariable hazard ratios (HRs). Results We identified 563,497 white and black women 18 to 64 years of age diagnosed with stage I to III breast cancer from 2004 to 2013 in the National Cancer Data Base. Among women with hormone receptor-positive disease, who represented 78.5% of all patients, the HR for death in black versus white women in the demographics-matched model was 2.05 (95% CI, 1.94 to 2.17). The HR decreased to 1.93 (95% CI, 1.83 to 2.04), 1.54 (95% CI, 1.47 to 1.62), 1.30 (95% CI, 1.24 to 1.36), and 1.25 (95% CI, 1.19 to 1.31) when sequentially matched for comorbidity, insurance, tumor characteristics, and treatment, respectively. These factors combined accounted for 76.3% of the total excess risk of death in black patients; insurance accounted for 37.0% of the total excess, followed by tumor characteristics (23.2%), comorbidities (11.3%), and treatment (4.8%). Results generally were similar among women with hormone receptor-negative disease, although the HRs were substantially smaller. Conclusion Matching by insurance explained one third of the excess risk of death among nonelderly black versus white women diagnosed with early-stage breast cancer; matching by tumor characteristics explained approximately one fifth of the excess risk. Efforts to focus on equalization of access to care could substantially reduce ethnic/racial disparities in overall survival among nonelderly women diagnosed with breast cancer.


Assuntos
Negro ou Afro-Americano/estatística & dados numéricos , Neoplasias da Mama/etnologia , Disparidades em Assistência à Saúde/estatística & dados numéricos , População Branca/estatística & dados numéricos , Adolescente , Adulto , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Feminino , Humanos , Seguro Saúde/estatística & dados numéricos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Modelos de Riscos Proporcionais , Receptores de Esteroides/metabolismo , Estados Unidos , Adulto Jovem
9.
J Mol Recognit ; 30(12)2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28639323

RESUMO

Dioxins and dioxin-like compounds (DLCs) are known to cause endocrine disruption in humans and animals. Being lipophilic xenobiotic chemicals, they can be easily absorbed into the biological system from the surrounding environments, thereby causing various health dysfunctions. In the present study, a total of 100 dioxins and DLCs were taken, and their binding pattern was assessed with the xenosensors pregnane X receptor (PXR) and constitutive androstane receptor (CAR) in comparison with the corresponding known inhibitors and a well-studied endocrine disrupting xenobiotic, bisphenol A (BPA). The nuclear receptors CAR and PXR are known to play a significant role in handling potential toxins by coordinating cellular transport and metabolic functions of the same. Among different endocrine-disrupting chemicals used in the present study, DLCs (PCDFs and PCBs) elicited better interactions in comparison with the parent dioxin (polychlorinated dibenzodioxins) compounds. On comparing D scores of all the compounds against both the receptors, PCDF 8-hydroxy-3,4-dichlorodibenzofuran (8-OH-DCDF) and PCB tetrachlorobenzyltoluene (TCBT) exhibited significant molecular interactions against PXR (-7.633 kcal mol-1 ) and CAR (-8.389 kcal mol-1 ), respectively. Predominant interactions were found to be H-bonding, π-π stacking, hydrophobic, polar, and van der Waals. By contrast, BPA and some natural ligands tested in this study showed lower binding affinities with these receptors than certain DLCs reported herein, ie, certain DLCs might be more toxic than the proven toxic agent, BPA. Such studies play a pivotal role in the risk assessment of exposure to dioxins and DLCs on human health.


Assuntos
Simulação por Computador , Dioxinas e Compostos Semelhantes a Dioxinas/química , Dioxinas e Compostos Semelhantes a Dioxinas/metabolismo , Receptores Citoplasmáticos e Nucleares/química , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores de Esteroides/metabolismo , Medição de Risco , Biocatálise , Receptor Constitutivo de Androstano , Interações Hidrofóbicas e Hidrofílicas , Ligantes , Simulação de Acoplamento Molecular , Receptor de Pregnano X , Receptores de Esteroides/química , Reprodutibilidade dos Testes
10.
Toxicol Mech Methods ; 27(2): 151-163, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27997270

RESUMO

Dioxins and dioxin-like compounds (DLCs) are the ones with poor water solubility and low volatility, resistant to physical, chemical and biological processes, persistent in the environment even under extreme conditions. Due to lipophilic nature, they get adhered to the fatty material and concentrate through biomagnification and bioaccumulation, thereby easily getting incorporated into food chains, paving the way to endocrine disruption via modulation of various human receptors. This in turn leads to certain adverse health effects. In the present study, a total of 100 dioxins and DLCs were taken and their binding pattern was assessed with the ketosteroid receptors, i.e. androgen (hAR), glucocorticoid (hGR), progesterone (hPR) and mineralocorticoid (hMR) in comparison to the corresponding natural steroids and a known endocrine disrupting xenobiotic, Bisphenol A (BPA). Most of the DLCs, particularly those bearing hydroxyl (-OH) group showed considerable affinities with ketosteroid receptors. On comparing D scores of all the dioxins and DLCs against all four receptors, compound 8-hydroxy-3,4-dichlorodibenzofuran(8-OH-DCDF) exhibited least D score of -9.549 kcal mol-1 against hAR. 3,8-Dihydroxy-2-chlorodibenzofuran(3,8-DiOH-CDF), 4'-hydroxy-2,3,4,5-tetrachlorobiphenyl (4'-OH-TCB) and 4-hydroxy-2,2',5'-trichlorobiphenyl(4-OH-TCB) also showed comparable molecular interactions with the ketosteroid receptors. These interactions mainly include H-bonding, π-π stacking, hydrophobic, polar and van der Waals' interactions. In contrast, BPA and some natural ligands tested in this study showed lower binding affinities with these receptors than certain DLCs reported herein, i.e. certain DLCs might be more toxic than the proven toxic agent, BPA. Such studies play a pivotal role in the risk assessment of exposure to dioxins and DLCs on human health.


Assuntos
Dioxinas/química , Disruptores Endócrinos/química , Cetosteroides/química , Receptores de Esteroides/química , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Ligantes , Simulação de Acoplamento Molecular , Ligação Proteica , Reprodutibilidade dos Testes , Medição de Risco
11.
In Vitro Cell Dev Biol Anim ; 51(9): 905-14, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25952767

RESUMO

A novel cell line, NRCAN-Tb521, was developed from larvae of the longhorn beetle Tylonotus bimaculatus (Coleoptera: Cerambycidae), a pest of North American ash trees. The cell line has been successfully passaged more than 50 times and displayed very strong attachment to the substrate and a modal chromosomal count distribution of 19. Sequencing of a 649 bp fragment of the mitochondrial cytochrome oxidase I gene confirmed the identity of NRCAN-Tb521 as T. bimaculatus. The response of the cell line to 20-hydroxyecdysone and diacylhydrazine ecdysone agonist insecticides was also studied. At 10(-6) M, 20-hydroxyecdysone, tebufenozide, methoxyfenozide and halofenozide triggered the production of numerous filamentous cytoplasmic extensions, and the cells tended to form aggregates, indicative of a cell differentiation response. This response was followed by a strong decrease in viability after 4 d. Reverse transcription polymerase chain reaction (PCR) experiments and sequencing of PCR fragments showed that the 20E receptor gene EcR is expressed in the cells and that 20E, tebufenozide, methoxyfenozide and halofenozide also induce the expression of the nuclear hormone receptor gene HR3. This report establishes that NRCAN-Tb521 is a valuable in vitro model to study effects of ecdysone agonists in wood-boring cerambycids.


Assuntos
Besouros/citologia , Besouros/efeitos dos fármacos , Inseticidas/farmacologia , Animais , Benzoatos/farmacologia , Linhagem Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos/métodos , Ecdisterona/agonistas , Ecdisterona/farmacologia , Complexo IV da Cadeia de Transporte de Elétrons/genética , Hidrazinas/farmacologia , Proteínas de Insetos/genética , Hormônios Juvenis/farmacologia , Cariotipagem , Receptores Citoplasmáticos e Nucleares/genética , Receptores de Esteroides/genética
12.
Environ Sci Pollut Res Int ; 22(19): 14442-54, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26022396

RESUMO

A combined chemical and biological analysis of samples from a major obsolete pesticide and persistent organic pollutant (POP) dumpsite in Northern Tajikistan was carried out. The chemical analytical screening focused on a range of prioritized compounds and compounds known to be present locally. Since chemical analytics does not allow measurements of hazards in complex mixtures, we tested the use of a novel effect-based approach using a panel of quantitative high-throughput CALUX reporter assays measuring distinct biological effects relevant in hazard assessment. Assays were included for assessing effects related to estrogen, androgen, and progestin signaling, aryl hydrocarbon receptor-mediated signaling, AP1 signaling, genotoxicity, oxidative stress, chemical hypoxia, and ER stress. With this panel of assays, we first quantified the biological activities of the individual chemicals measured in chemical analytics. Next, we calculated the expected sum activity by these chemicals in the samples of the pesticide dump site and compared the results with the measured CALUX bioactivity of the total extracts of these samples. The results showed that particularly endocrine disruption-related effects were common among the samples. This was consistent with the toxicological profiles of the individual chemicals that dominated these samples. However, large discrepancies between chemical and biological analysis were found in a sample from a burn place present in this site, with biological activities that could not be explained by chemical analysis. This is likely to be caused by toxic combustion products or by spills of compounds that were not targeted in the chemical analysis.


Assuntos
Misturas Complexas/análise , Disruptores Endócrinos/análise , Monitoramento Ambiental/métodos , Substâncias Perigosas/análise , Praguicidas/análise , Instalações de Eliminação de Resíduos , Bioensaio/métodos , Linhagem Celular Tumoral , Misturas Complexas/química , Misturas Complexas/toxicidade , Disruptores Endócrinos/toxicidade , Genes Reporter , Substâncias Perigosas/toxicidade , Humanos , Luciferases/genética , Praguicidas/toxicidade , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo , Receptores de Esteroides/genética , Receptores de Esteroides/metabolismo , Medição de Risco , Tadjiquistão , Transcrição Gênica/efeitos dos fármacos
13.
Ann Pathol ; 34(5): 366-72, 2014 Oct.
Artigo em Francês | MEDLINE | ID: mdl-25439989

RESUMO

Biomarker assessment of breast cancer tumor samples is part of the routine workflow of pathology laboratories. International guidelines have recently been updated, with special regards to the pre-analytical steps that are critical for the quality of immunohistochemical and in situ hybridization procedures, whatever the biomarker analyzed. Fixation and specimen handling protocols must be standardized, validated and carefully tracked. Cooperation and training of the personnel involved in the specimen workflow (e.g. radiologists, surgeons, nurses, technicians and pathologists) are of paramount importance. The GEFPICS' update of the recommendations herein details and comments the different steps of the pre-analytical process. Application of these guidelines and participation to quality insurance programs are mandatory to ensure the correct evaluation of oncotheranostic biomarkers.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/química , Imuno-Histoquímica/métodos , Hibridização In Situ/métodos , Receptor ErbB-2/análise , Receptores de Esteroides/análise , Neoplasias da Mama/patologia , Feminino , Fixadores , França , Técnicas Histológicas , Humanos , Prognóstico , Controle de Qualidade , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Manejo de Espécimes/métodos
14.
Gen Comp Endocrinol ; 194: 152-61, 2013 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-24084592

RESUMO

Cortisol is a pleiotropic glucocorticoid hormone that acts through the intracellular glucocorticoid receptors (GR). Cortisol affects many important biological functions in mammals, including immune function, behavior, stress, metabolism, growth and organogenesis. In fishes, cortisol has an additional function in the osmoregulatory activity of ionocytes (ICs). Although much progress has been made toward understanding cortisol action at the levels of adult osmoregulatory tissues, the developmental functions of cortisol and its receptors in ICs remain to be clarified. We first analyzed the total contents of both cortisol and corticosteroid receptor mRNAs (GR1, GR2 and MR) during medaka development. Although low levels of cortisol were detected during development of the medaka embryo, maternal GR1, GR2 and MR transcripts were detected at higher levels than zygotic transcripts. We investigated the effect of exogenous cortisol on IC number during medaka embryogenesis. We observed that cortisol treatment induced an earlier expansion of the IC population but did not modify the final IC number. Using functional genomic approaches, we also tested the involvement of GR1, GR2 and mineralocorticoid receptor (MR) in IC development by systematic knock-down with translation-blocking morpholinos. Only GR2 knock-down led to a reduction of the total number of ICs in the epidermis. In addition, a GR2 splice-blocking morpholino did not have any effect on the biogenesis of ICs, underscoring the importance of maternally inherited GR2 mRNAs. We propose that maternal GR2, but not GR1 or MR, is a major pathway in the IC biogenesis in medaka most likely through cortisol activation, and that cortisol exposition fine-tunes their developmental timing. These findings provide a framework for future research on the regulatory functions of corticosteroids in euryhaline fishes and provide medaka as an advantageous model to further elucidate the underlying molecular regulatory mechanisms of IC development.


Assuntos
Hidrocortisona/metabolismo , Oryzias/embriologia , Oryzias/metabolismo , Receptores de Esteroides/metabolismo , Animais , Embrião não Mamífero/metabolismo , Desenvolvimento Embrionário/efeitos dos fármacos , Proteínas de Peixes/genética , Proteínas de Peixes/metabolismo , Reação em Cadeia da Polimerase , Radioimunoensaio , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo , Receptores de Mineralocorticoides/genética , Receptores de Mineralocorticoides/metabolismo , Receptores de Esteroides/genética
15.
PLoS One ; 8(7): e66979, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23894282

RESUMO

BACKGROUND: The association between rs13387042 polymorphism on 2q35 and breast cancer (BC) has been widely evaluated since it was first identified through genome-wide association approach. However, the results have been inconclusive. To investigate this inconsistency, we performed a meta-analysis of all available studies dealing with the relationship between the 2q35-rs13387042 polymorphism and BC. METHODS: Databases including MEDLINE, PubMed, EMBASE, ISI web of science and CNKI (China National Knowledge Infrastructure) were searched to find relevant studies. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of association. The random-effects model was applied, addressing heterogeneity and publication bias. RESULTS: A total of 24 articles involving 99,772 cases and 164,985 controls were included. In a combined analysis, the summary per-allele odds ratio (OR) for BC of 2q35-rs13387042 polymorphism was 1.13 (95% CI: 1.11-1.16; P<10(-5)). Significant associations were also detected under co-dominant, dominant and recessive genetic models. In the subgroup analysis by ethnicity, significantly increased risks were found in Asians, Caucasians and Hispanic whites for the polymorphism in all comparisons; whereas no significant associations were found among Africans. In addition, we find 2q35-rs13387042 polymorphism conferred significantly risks for both ER-positive and ER-negative tumors. Furthermore, significant associations were also detected both in PR-positive and PR-negative cancer. CONCLUSIONS: Our findings demonstrated that rs13387042-A allele is a risk-conferring factors for the development of BC, especially in Asians, Caucasians and Hispanic whites.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Cromossomos Humanos Par 2/genética , Predisposição Genética para Doença/genética , Polimorfismo de Nucleotídeo Único , Receptores de Esteroides/metabolismo , Humanos
16.
Eur J Nucl Med Mol Imaging ; 40(1): 72-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23053321

RESUMO

PURPOSE: The aim of this study was to analyse the correlation between dual-time-point (18)F-2-deoxy-2-fluoro-D-glucose (FDG) uptakes in lymph nodes assessed by positron emission tomography (PET)/CT and histopathological and immunohistochemical prognostic factors. METHODS: Seventy-five women with locally advanced breast cancer were prospectively evaluated. PET/CT was requested in the initial staging previous to adjuvant chemotherapy (multicentre study). All of the patients underwent (18)F-FDG PET/CT with a dual-time-point acquisition. Both examinations were evaluated qualitatively and semi-quantitatively with calculation of maximum standardized uptake values (SUV(max)) in PET-1 (SUV-1) and in PET-2 (SUV-2) and the percentage variation of the SUV or retention index (RI) between PET-1 and PET-2 in lymph nodes with the greater (18)F-FDG uptake. The biological prognostic parameters such as the steroid receptor status, p53 and HER2 expression, proliferation rate (Ki-67) and grading were determined from tissue of the primary tumour. Metabolic and biological parameters were correlated using Spearman's rank-order correlation coefficient and Mann-Whitney U and Kruskal-Wallis tests. RESULTS: Negative receptor status was correlated with higher SUV-1, SUV-2 and RI in lymph nodes. The results were significant for progesterone receptor status. p53 over-expression and triple-negative status were associated with greater semi-quantitative parameters in lymph nodes. Higher tumoural grades were related with greater semi-quantitative parameters (p > 0.05). CONCLUSION: Biological factors of bad prognosis were correlated with higher semi-quantitative metabolic values in lymph nodes. Therefore these results appear to reveal biological significance of lymph node (18)F-FDG accumulation.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Fluordesoxiglucose F18 , Linfonodos/diagnóstico por imagem , Imagem Multimodal , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Adulto , Idoso , Neoplasias da Mama/química , Neoplasias da Mama/terapia , Proliferação de Células , Quimioterapia Adjuvante , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Receptor ErbB-2/análise , Receptores de Esteroides/análise , Estatísticas não Paramétricas , Proteína Supressora de Tumor p53/análise
17.
Environ Toxicol Chem ; 31(12): 2748-56, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22949087

RESUMO

The impact of a full-scale biosolid composting plant on the fate of a broad range of priority organic pollutants was investigated. Chemical analysis was performed at different steps of the process during two seasons. Simultaneously, the toxicological quality was assessed using estrogen α-, dioxin-, and pregnane X-receptor reporter cell lines. Mass-balance calculation highlighted the removal of easily degradable pollutants during composting. The important variations observed for each compound and for the two seasons might be explained by pollutant-fate dependency on process parameters like temperature. The final compost displayed low pregnane X activity but high estrogenic activity. The dioxin-like activity stayed constant through the process. The chemical and toxicological results highlight the importance of combining both approaches to accurately assess the compost quality. Such compilation of data on full-scale processes may be also very helpful for the environmental risk assessment of new organic waste disposal practices.


Assuntos
Poluentes do Solo/toxicidade , Solo/química , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/toxicidade , Linhagem Celular , Células HeLa , Humanos , Células MCF-7 , Receptor de Pregnano X , Receptores de Hidrocarboneto Arílico/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Esteroides/metabolismo , Medição de Risco , Temperatura , Testes de Toxicidade
18.
Breast Cancer Res Treat ; 133(2): 759-68, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22315134

RESUMO

The 70-gene prognosis-signature is validated as a good predictor of recurrence for hormone receptor-positive (ER+), lymph node-negative (LN-), human epidermal growth factor receptor type 2-negative (HER2-) early stage breast cancer (ESBC) in Japanese patient population. Its high cost and potential in avoiding unnecessary adjuvant chemotherapy arouse interest in its economic impact. This study evaluates the cost-effectiveness of including the assay into Japan's social health insurance benefit package. An economic decision tree and Markov model under Japan's health system from the societal perspective is constructed with clinical evidence from the pool analysis of validation studies. One-way sensitivity analyses are also performed. Incremental cost-effectiveness ratio is estimated as ¥3,873,922/quality adjusted life year (QALY) (US$43,044/QALY), which is not more than the suggested social willingness-to-pay for one QALY gain from an innovative medical intervention in Japan, ¥5,000,000/QALY (US$55,556/QALY). However, sensitivity analyses show the instability of this estimation. The introduction of the assay into Japanese practice of ER+, LN-, HER2- ESBC treatment by including it to Japan's social health insurance benefit package has a reasonable chance to be judged as cost-effective and may be justified as an efficient deployment of finite health care resources.


Assuntos
Neoplasias da Mama/economia , Neoplasias da Mama/genética , Perfilação da Expressão Gênica/economia , Neoplasias da Mama/diagnóstico , Análise Custo-Benefício , Árvores de Decisões , Feminino , Humanos , Japão , Linfonodos/patologia , Estadiamento de Neoplasias , Prognóstico , Receptor ErbB-2/análise , Receptores de Esteroides/análise , Recidiva
19.
Lancet Oncol ; 12(12): 1101-8, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22018631

RESUMO

BACKGROUND: Postmenopausal women with hormone receptor-positive early breast cancer have persistent, long-term risk of breast-cancer recurrence and death. Therefore, trials assessing endocrine therapies for this patient population need extended follow-up. We present an update of efficacy outcomes in the Breast International Group (BIG) 1-98 study at 8·1 years median follow-up. METHODS: BIG 1-98 is a randomised, phase 3, double-blind trial of postmenopausal women with hormone receptor-positive early breast cancer that compares 5 years of tamoxifen or letrozole monotherapy, or sequential treatment with 2 years of one of these drugs followed by 3 years of the other. Randomisation was done with permuted blocks, and stratified according to the two-arm or four-arm randomisation option, participating institution, and chemotherapy use. Patients, investigators, data managers, and medical reviewers were masked. The primary efficacy endpoint was disease-free survival (events were invasive breast cancer relapse, second primaries [contralateral breast and non-breast], or death without previous cancer event). Secondary endpoints were overall survival, distant recurrence-free interval (DRFI), and breast cancer-free interval (BCFI). The monotherapy comparison included patients randomly assigned to tamoxifen or letrozole for 5 years. In 2005, after a significant disease-free survival benefit was reported for letrozole as compared with tamoxifen, a protocol amendment facilitated the crossover to letrozole of patients who were still receiving tamoxifen alone; Cox models and Kaplan-Meier estimates with inverse probability of censoring weighting (IPCW) are used to account for selective crossover to letrozole of patients (n=619) in the tamoxifen arm. Comparison of sequential treatments to letrozole monotherapy included patients enrolled and randomly assigned to letrozole for 5 years, letrozole for 2 years followed by tamoxifen for 3 years, or tamoxifen for 2 years followed by letrozole for 3 years. Treatment has ended for all patients and detailed safety results for adverse events that occurred during the 5 years of treatment have been reported elsewhere. Follow-up is continuing for those enrolled in the four-arm option. BIG 1-98 is registered at clinicaltrials.govNCT00004205. FINDINGS: 8010 patients were included in the trial, with a median follow-up of 8·1 years (range 0-12·4). 2459 were randomly assigned to monotherapy with tamoxifen for 5 years and 2463 to monotherapy with letrozole for 5 years. In the four-arm option of the trial, 1546 were randomly assigned to letrozole for 5 years, 1548 to tamoxifen for 5 years, 1540 to letrozole for 2 years followed by tamoxifen for 3 years, and 1548 to tamoxifen for 2 years followed by letrozole for 3 years. At a median follow-up of 8·7 years from randomisation (range 0-12·4), letrozole monotherapy was significantly better than tamoxifen, whether by IPCW or intention-to-treat analysis (IPCW disease-free survival HR 0·82 [95% CI 0·74-0·92], overall survival HR 0·79 [0·69-0·90], DRFI HR 0·79 [0·68-0·92], BCFI HR 0·80 [0·70-0·92]; intention-to-treat disease-free survival HR 0·86 [0·78-0·96], overall survival HR 0·87 [0·77-0·999], DRFI HR 0·86 [0·74-0·998], BCFI HR 0·86 [0·76-0·98]). At a median follow-up of 8·0 years from randomisation (range 0-11·2) for the comparison of the sequential groups with letrozole monotherapy, there were no statistically significant differences in any of the four endpoints for either sequence. 8-year intention-to-treat estimates (each with SE ≤1·1%) for letrozole monotherapy, letrozole followed by tamoxifen, and tamoxifen followed by letrozole were 78·6%, 77·8%, 77·3% for disease-free survival; 87·5%, 87·7%, 85·9% for overall survival; 89·9%, 88·7%, 88·1% for DRFI; and 86·1%, 85·3%, 84·3% for BCFI. INTERPRETATION: For postmenopausal women with endocrine-responsive early breast cancer, a reduction in breast cancer recurrence and mortality is obtained by letrozole monotherapy when compared with tamoxifen montherapy. Sequential treatments involving tamoxifen and letrozole do not improve outcome compared with letrozole monotherapy, but might be useful strategies when considering an individual patient's risk of recurrence and treatment tolerability. FUNDING: Novartis, United States National Cancer Institute, International Breast Cancer Study Group.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/análise , Neoplasias da Mama/tratamento farmacológico , Pós-Menopausa , Receptores de Esteroides/análise , Inibidores da Aromatase/administração & dosagem , Austrália , Neoplasias da Mama/química , Neoplasias da Mama/mortalidade , Neoplasias da Mama/secundário , Estudos Cross-Over , Intervalo Livre de Doença , Método Duplo-Cego , Europa (Continente) , Feminino , Humanos , Estimativa de Kaplan-Meier , Letrozol , Recidiva Local de Neoplasia , Segunda Neoplasia Primária , Nova Zelândia , Nitrilas/administração & dosagem , América do Norte , Modelos de Riscos Proporcionais , Fatores de Risco , Moduladores Seletivos de Receptor Estrogênico/administração & dosagem , África do Sul , América do Sul , Tamoxifeno/administração & dosagem , Fatores de Tempo , Resultado do Tratamento , Triazóis/administração & dosagem
20.
J Pharmacol Toxicol Methods ; 63(3): 223-6, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21111054

RESUMO

INTRODUCTION: The human nuclear receptors pregnane X receptor (PXR), constitutive androstane receptor (CAR), and aryl hydrocarbon receptor (AhR) are known to regulate gene expression of the cytochrome P450 (CYP) enzymes, 3A4, 2B6, and 1A2, respectively. In conventional CYP induction studies, the activity of each CYP enzyme is assessed in a separate incubation with the appropriate marker substrate. The objective of this study was to assess, simultaneously, the induction of CYP3A4, CYP2B6, and CYP1A2 activity in cultured human hepatocytes treated with various prototypical ligands of PXR, CAR, and AhR by utilizing an optimized substrate cocktail, as well as a rapid, sensitive liquid chromatography-mass spectrometry method. METHODS: To evaluate the xenobiotic-mediated induction of hepatocellular gene expression, the prototypical inducers rifampicin (10 µM) and phenobarbital (1 mM) were used for CYP3A4, CITCO (1 µM) and artemisinin (50 µM) were used for CYP2B6, and 3-methylcholanthrene (1 µM) and omeprazole (50 µM) were utilized for induction of CYP1A2. Primary human hepatocytes were treated with each compound for 48h, followed by a 30-min incubation of the hepatocyte culture along with the addition of three marker substrates for specific CYP activity: midazolam (CYP3A4; 5 µM), bupropion (CYP2B6; 50 µM), and phenacetin (CYP1A2; 100µM). The assessment of CYP activity was performed with a rapid, sensitive liquid chromatography-tandem mass spectrometry method which simultaneously assessed activity of CYP3A4, CYP2B6, and CYP1A2 in a single 3-min method by examining the formation of the probe substrate metabolites, 1'-hydroxymidazolam, hydroxybupropion, and acetaminophen, respectively. RESULTS: The average fold-induction of CYP3A4, CYP2B6, and CYP1A2 activity was comparable between the cocktail and the conventional assay. DISCUSSION: The combination of three marker substrates in a single 30-min incubation, in addition to a rapid, sensitive LC-MS/MS method, resulted in an efficient and robust method for assessing cytochrome P450 induction as compared to the conventional methodology.


Assuntos
Hidrocarboneto de Aril Hidroxilases/biossíntese , Citocromo P-450 CYP1A2/biossíntese , Citocromo P-450 CYP3A/biossíntese , Descoberta de Drogas/métodos , Hepatócitos/enzimologia , Oxirredutases N-Desmetilantes/biossíntese , Técnicas de Cultura de Células , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Receptor Constitutivo de Androstano , Citocromo P-450 CYP2B6 , Indução Enzimática , Hepatócitos/efeitos dos fármacos , Humanos , Ligantes , Receptor de Pregnano X , Receptores de Hidrocarboneto Arílico/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores de Esteroides/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Especificidade por Substrato , Espectrometria de Massas em Tandem , Xenobióticos/farmacologia
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