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1.
Genes Dev ; 27(8): 916-27, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-23630076

RESUMO

Depending on the circumstance, FOXO (Forkhead O) (FOXO1, FOXO3, and FOXO4) transcription factors activate the expression of markedly different sets of genes to produce different phenotypic effects. For example, distinct FOXO-regulated transcriptional programs stimulate cell death or enhance organism life span. To gain insight into how FOXOs select specific genes for regulation, we performed a screen for genes that modify FOXO activation of TRAIL, a death receptor ligand capable of inducing extrinsic apoptosis. We discovered that the bZIP transcriptional repressor NFIL3 (nuclear factor interleukin 3-regulated) hindered FOXO transcription factor access to chromatin at the TRAIL promoter by binding to nearby DNA and recruiting histone deacetylase-2 (HDAC2) to reduce histone acetylation. In the same manner, NFIL3 repressed expression of certain FOXO targets--e.g., FAS, GADD45α (growth arrest and DNA damage-inducible, α), and GADD45ß--but not others. NFIL3, which we found to be overexpressed in different cancers, supported tumor cell survival largely through repression of TRAIL and antagonized hydrogen peroxide-induced cell death. Moreover, its expression in cancer was associated with lower patient survival. Therefore, NFIL3 alters cancer cell behavior and FOXO function by acting on chromatin to restrict the menu of FOXO target genes. Targeting of NFIL3 could be of therapeutic benefit for cancer patients.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Regulação Neoplásica da Expressão Gênica , Apoptose/genética , Fatores de Transcrição de Zíper de Leucina Básica/genética , Sítios de Ligação , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/fisiopatologia , Linhagem Celular Tumoral , Cromatina/metabolismo , Proteína Forkhead Box O1 , Células HEK293 , Histona Desacetilases/metabolismo , Humanos , Estimativa de Kaplan-Meier , Prognóstico , Regiões Promotoras Genéticas , Ligação Proteica , RNA Interferente Pequeno/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/genética
2.
Int J Mol Sci ; 22(8)2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33921510

RESUMO

Rare diseases affect a small part of the population, and the most affected are children. Because of the low availability of patients for testing, the pharmaceutical industry cannot develop drugs for the diagnosis of many of these orphan diseases. In this sense, the use of benzothiazole compounds that are highly selective and can act as spectroscopy probes, especially the compound 2-(4'-aminophenyl)benzothiazole (ABT), has been highlighted. This article reports the design of potential contrast agents based on ABT and iron to develop a new material with an efficient mechanism to raise the relaxation rate, facilitating diagnosis. The ABT/δ-FeOOH hybrid material was prepared by grafting (N-(4'-aminophenyl) benzothiazole-2-bromoacetamide) on the surface of the iron oxyhydroxide particles. FTIR spectra confirmed the material formations of the hybrid material ABT/δ-FeOOH. SEM analysis checked the covering of nanoflakes' surfaces in relation to the morphology of the samples. The theoretical calculations test a better binding mode of compound with iron oxyhydroxide. Theoretical findings show the radical capture mechanism in the stabilization of this new material. In this context, Fe3+ ions are an electron acceptor from the organic phase.


Assuntos
Benzotiazóis/química , Meios de Contraste/uso terapêutico , Compostos Férricos/química , Doenças Raras/diagnóstico , Meios de Contraste/química , Humanos , Íons/química , Ferro/química , Fenômenos Magnéticos , Doenças Raras/diagnóstico por imagem , Doenças Raras/patologia , Análise Espectral
3.
Fam Cancer ; 22(2): 127-133, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36207653

RESUMO

Cascade testing for familial cancer syndromes has historically been difficult to execute. As part of a facilitated cascade testing pathway, we evaluated barriers to completion of cascade testing. Our previously published study evaluated a facilitated cascade testing pathway whereby a genetics team facilitated at-risk relative (ARR) cascade testing through telephone genetic counseling and mailed saliva kit testing. This follow-up study evaluated barriers to completion of cascade genetic testing through six-month follow-up telephone interviews. Probands identified 114 ARRs, of whom 97 were successfully contacted by telephone. Among those contacted, 83 (86%) reported interest in genetic testing and 14 (14%) declined. Among those reporting interest in testing, 71% (69/83) completed testing. Follow-up telephone interviews revealed that 14 ARRs did not complete testing despite reporting interest for the following reasons: concern about genetic discrimination, fear of a positive result and belief that the pathogenic variant was not relevant to his/her health. Five ARRs reported that they remained interested in testing and the telephone call prompted completion of testing. Even when facilitated by a medical team with prioritization of relative convenience, significant barriers to cascade testing ARRs for hereditary breast and ovarian cancer syndrome persist due to concern about genetic discrimination, cost, and fear of positive test results.


Assuntos
Neoplasias da Mama , Síndrome Hereditária de Câncer de Mama e Ovário , Neoplasias Ovarianas , Feminino , Humanos , Masculino , Síndrome Hereditária de Câncer de Mama e Ovário/diagnóstico , Síndrome Hereditária de Câncer de Mama e Ovário/genética , Predisposição Genética para Doença , Seguimentos , Testes Genéticos , Aconselhamento Genético/métodos , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/genética
4.
J Mol Model ; 27(9): 249, 2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34387739

RESUMO

The development of bifunctional catalysts is of great interest in fine chemistry, since they are capable of promoting multicatalytic reactions involved in several important industrial processes. Iron oxyhydroxides have been identified as low-cost bifunctional catalysts. However, their applications are limited due to their weak acid character. Thus, elaborated modifications of these systems can significantly contribute to increasing their activities and selectivity. This work consists in the study, through DFT calculations, of the properties of the bulk and the surface of feroxyhyte (δ-FeOOH) doped with niobium, as a potential bifunctional catalyst. We identified the formation of stronger van der Waals interactions among the doped δ-FeOOH layers, which can increase the thermal stability of the catalyst. In addition, evidence has been found that the insertion of Nb increases Brönsted acidity and gives rise to new Lewis acid sites on the catalyst surface.

5.
J Clin Oncol ; 38(13): 1389-1397, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-31922918

RESUMO

PATIENTS AND METHODS: Probands with newly diagnosed cancer-associated pathogenic variants were offered facilitated cascade testing whereby the genetics team identified and contacted ARRs by telephone to disclose the familial pathogenic variant and offer telephone counseling and mailed saliva testing. Results and guideline-based recommendations were reviewed by telephone and shared with the primary care physician. RESULTS: Thirty probands were enrolled, and 114 ARRs were identified. Twelve ARRs were excluded (lived outside of the United States, n = 5; proband did not approve of contact, n = 7). Among 102 ARRs telephoned, contact was established with 95 (93%). Among 114 identified ARRs, 66 (58%) completed genetic testing. Among those completing testing, 27 (41%) carried the familial pathogenic variant. Surveys of ARRs at the time of genetic testing and 6 months later demonstrated low levels of anxiety, depression, distress, and uncertainty and high levels of satisfaction with testing. At 6 months, 7 ARRs with pathogenic variants had undergone cancer surveillance interventions and 4 had undergone cancer risk-reducing surgery. CONCLUSION: Facilitated cascade testing with telephone genetic counseling and mailed saliva kits resulted in high testing uptake among ARRs. Positive genetic testing resulted in utilization of genetically targeted primary disease prevention at short-term follow-up. Facilitated cascade testing is a straightforward, low-cost, easily implemented strategy with significant potential to promote early detection for affected ARRs and reduce cancer mortality and should be evaluated in larger scale clinical trials.


Assuntos
Aconselhamento Genético/métodos , Testes Genéticos/métodos , Entrevistas como Assunto/métodos , Neoplasias/genética , Qualidade de Vida/psicologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Ansiedade/psicologia , Depressão/psicologia , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/prevenção & controle , Neoplasias/psicologia , Estudos Prospectivos , Reprodutibilidade dos Testes , Estresse Psicológico/psicologia , Inquéritos e Questionários/estatística & dados numéricos , Adulto Jovem
6.
Microbes Infect ; 8(11): 2569-77, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16938478

RESUMO

We investigated the role of the platelet activation factor (PAF) receptor (PAFR) in the outcome of infection with Leishmania amazonensis. PAFR deficient (PAFR(-/-)) mice were infected with L. amazonensis and the course of infection was followed. We found that PAFR(-/-) mice in the C57BL/6 background were more susceptible to infection with L. amazonensis than the wild-type controls, as seen both by lesion size and parasite number at the site of infection. Interferon (IFN)-gamma production was delayed in PAFR(-/-) mice, and lower levels of Ccl5 were found in lesions. Expression of nitric oxide synthase-2 mRNA was found impaired in PAFR(-/-) associated with higher levels of arginase-1 mRNA. Moreover, higher levels of antibodies were produced in response to L. amazonensis by PAFR(-/-) mice. We conclude that signaling through the PAFR is essential for the ability of the murine host to control L. amazonensis infection by driving an adequate immune response.


Assuntos
Interferon gama/biossíntese , Leishmania mexicana/imunologia , Leishmaniose Cutânea/imunologia , Glicoproteínas da Membrana de Plaquetas/deficiência , Receptores Acoplados a Proteínas G/deficiência , Animais , Anticorpos Antiprotozoários/sangue , Arginase/biossíntese , Quimiocina CCL1 , Quimiocina CCL5 , Quimiocinas CC/análise , Modelos Animais de Doenças , Suscetibilidade a Doenças , Expressão Gênica , Histocitoquímica , Imunoglobulina G/sangue , Interleucina-10/análise , Leishmaniose Cutânea/parasitologia , Leishmaniose Cutânea/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Óxido Nítrico Sintase Tipo II/biossíntese , Glicoproteínas da Membrana de Plaquetas/genética , RNA Mensageiro/análise , RNA Mensageiro/genética , Receptores Acoplados a Proteínas G/genética , Fator de Necrose Tumoral alfa/análise , Regulação para Cima
7.
Artigo em Inglês | MEDLINE | ID: mdl-26099826

RESUMO

Lead (Pb) is known by its toxicity both for animals and plants. In order to evaluate its toxicity, plants of Brachiaria brizantha were cultivated on nutritive solution of Hoagland during 90 days and submitted to different concentrations of Pb. The content of macro and micronutrients was evaluated and there was a reduction on root content of Ca, besides the lowest dosages of Pb had induced an increase of N, S, Mn, Cu, Zn and Fe. The cell ultrastructure of leaves and roots were analyzed by transmission electronic microscopy (TEM). Among the main alterations occurred there were invaginations on cell walls, the presence of crystals on the root cells, accumulation of material on the interior of cells and vacuolar compartmentalization. On the leaves the degradation of chloroplasts was observed, as well as the increase of vacuoles. Structures for the formation of oxalate crystals were proposed through molecular modeling and thermodynamic stability. Calculi suggest the formation of highly stable metal-oxalate complexes.


Assuntos
Brachiaria/metabolismo , Brachiaria/ultraestrutura , Cálcio/metabolismo , Complexos de Coordenação/metabolismo , Chumbo/metabolismo , Oxalatos/metabolismo , Chumbo/toxicidade , Modelos Moleculares , Folhas de Planta/metabolismo , Folhas de Planta/ultraestrutura , Raízes de Plantas/metabolismo , Raízes de Plantas/ultraestrutura , Termodinâmica
8.
Oncotarget ; 5(21): 10503-17, 2014 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25361177

RESUMO

Basal-like breast cancers (BBCs) are enriched for increased EGFR expression and decreased expression of PTEN. We found that treatment with metformin and erlotinib synergistically induced apoptosis in a subset of BBC cell lines. The drug combination led to enhanced reduction of EGFR, AKT, S6 and 4EBP1 phosphorylation, as well as prevented colony formation and inhibited mammosphere outgrowth. Our data with other compounds suggested that biguanides combined with EGFR inhibitors have the potential to outperform other targeted drug combinations and could be employed in other breast cancer subtypes, as well as other tumor types, with activated EGFR and PI3K signaling. Analysis of BBC cell line alterations led to the hypothesis that loss of PTEN sensitized cells to the drug combination which was confirmed using isogenic cell line models with and without PTEN expression. Combined metformin and erlotinib led to partial regression of PTEN-null and EGFR-amplified xenografted MDA-MB-468 BBC tumors with evidence of significant apoptosis, reduction of EGFR and AKT signaling, and lack of altered plasma insulin levels. Combined treatment also inhibited xenografted PTEN null HCC-70 BBC cells. Measurement of trough plasma drug levels in xenografted mice and a separately performed pharmacokinetics modeling study support possible clinical translation.


Assuntos
Apoptose/efeitos dos fármacos , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/tratamento farmacológico , Sinergismo Farmacológico , Metformina/farmacologia , Quinazolinas/farmacologia , Animais , Protocolos de Quimioterapia Combinada Antineoplásica , Western Blotting , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/metabolismo , Cloridrato de Erlotinib , Feminino , Citometria de Fluxo , Humanos , Hipoglicemiantes/farmacologia , Técnicas Imunoenzimáticas , Camundongos , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Eur J Med Chem ; 87: 611-23, 2014 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-25299683

RESUMO

A virtual screening procedure was applied to identify new tankyrase inhibitors. Through pharmacophore screening of a compounds collection from the SPECS database, the methoxy[l]benzothieno[2,3-c]quinolin-6(5H)-one scaffold was identified as nicotinamide mimetic able to inhibit tankyrase activity at low micromolar concentration. In order to improve potency and selectivity, tandem structure-based and scaffold hopping approaches were carried out over the new scaffold leading to the discovery of the 2-(phenyl)-3H-benzo[4,5]thieno[3,2-d]pyrimidin-4-one as powerful chemotype suitable for tankyrase inhibition. The best compound 2-(4-tert-butyl-phenyl)-3H-benzo[4,5]thieno[3,2-d]pyrimidin-4-one (23) displayed nanomolar potencies (IC50s TNKS-1 = 21 nM and TNKS-2 = 29 nM) and high selectivity when profiled against several other PARPs. Furthermore, a striking Wnt signaling, as well as cell growth inhibition, was observed assaying 23 in DLD-1 cancer cells.


Assuntos
Inibidores Enzimáticos/farmacologia , Tanquirases/antagonistas & inibidores , Inibidores Enzimáticos/química , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Espectrometria de Massas por Ionização por Electrospray
10.
Cancer Biol Ther ; 14(3): 246-53, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23291982

RESUMO

Breast cancer can be classified into different molecular subtypes with varying clinical and pathological characteristics. The basal-like breast cancer subtype represents one of the most aggressive and lethal types of breast cancer, and due to poor mechanistic understanding, it lacks targeted therapy. Many basal-like breast cancer patient samples display alterations of established drivers of cancer development, including elevated expression of EGFR, p53 inactivating mutations and loss of expression of the tumor suppressor PTEN; however, their contribution to human basal-like breast cancer pathogenesis remains ill-defined. Using non-transformed human mammary epithelial cells, we set out to determine whether altering EGFR, p53 and PTEN in different combinations could contribute to basal-like breast cancer progression through transformation of cells. Altering PTEN in combination with either p53 or EGFR in contrast to any of the single alterations caused increased growth of transformed colonies in soft agar. Concomitantly modifying all three genes led to the highest rate of cellular proliferation and the greatest degree of anchorage-independent colony formation. Results from our effort to engineer a model of BBC expressing alterations of EGFR, p53 and PTEN suggest that these changes are cooperative and likely play a causal role in basal-like breast cancer pathogenesis. Consideration should be given to targeting EGFR and restoring p53 and PTEN signaling simultaneously as a strategy for treatment of this subtype of breast cancer.


Assuntos
Neoplasias da Mama/genética , Transformação Celular Neoplásica/genética , Receptores ErbB/genética , Neoplasia de Células Basais/genética , PTEN Fosfo-Hidrolase/genética , Proteína Supressora de Tumor p53/genética , Animais , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Fator de Crescimento Epidérmico/farmacologia , Receptores ErbB/metabolismo , Feminino , Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Técnicas de Inativação de Genes , Humanos , Camundongos , Modelos Biológicos , Neoplasia de Células Basais/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Transdução de Sinais , Transplante Heterólogo , Ensaio Tumoral de Célula-Tronco , Proteína Supressora de Tumor p53/metabolismo
12.
Cancer Res ; 69(11): 4674-81, 2009 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-19470766

RESUMO

Recent insights into the role of the von-Hippel Lindau (VHL) tumor suppressor gene in hereditary and sporadic clear-cell renal cell carcinoma (ccRCC) have led to new treatments for patients with metastatic ccRCC, although virtually all patients eventually succumb to the disease. We performed an integrated, genome-wide analysis of copy-number changes and gene expression profiles in 90 tumors, including both sporadic and VHL disease-associated tumors, in hopes of identifying new therapeutic targets in ccRCC. We identified 14 regions of nonrandom copy-number change, including 7 regions of amplification (1q, 2q, 5q, 7q, 8q, 12p, and 20q) and 7 regions of deletion (1p, 3p, 4q, 6q, 8p, 9p, and 14q). An analysis aimed at identifying the relevant genes revealed VHL as one of three genes in the 3p deletion peak, CDKN2A and CDKN2B as the only genes in the 9p deletion peak, and MYC as the only gene in the 8q amplification peak. An integrated analysis to identify genes in amplification peaks that are consistently overexpressed among amplified samples confirmed MYC as a potential target of 8q amplification and identified candidate oncogenes in the other regions. A comparison of genomic profiles revealed that VHL disease-associated tumors are similar to a subgroup of sporadic tumors and thus more homogeneous overall. Sporadic tumors without evidence of biallelic VHL inactivation fell into two groups: one group with genomic profiles highly dissimilar to the majority of ccRCC and a second group with genomic profiles that are much more similar to tumors with biallelic inactivation of VHL.


Assuntos
Carcinoma de Células Renais/genética , Dosagem de Genes , Perfilação da Expressão Gênica , Neoplasias Renais/genética , Doença de von Hippel-Lindau/genética , Carcinoma de Células Renais/complicações , Carcinoma de Células Renais/patologia , Linhagem Celular Tumoral , Hibridização Genômica Comparativa , Regulação Neoplásica da Expressão Gênica , Frequência do Gene , Estudo de Associação Genômica Ampla , Humanos , Rim/patologia , Neoplasias Renais/complicações , Neoplasias Renais/patologia , Metástase Neoplásica , Polimorfismo de Nucleotídeo Único , Proteína Supressora de Tumor Von Hippel-Lindau/genética , Doença de von Hippel-Lindau/complicações , Doença de von Hippel-Lindau/patologia
13.
Nat Genet ; 40(1): 102-7, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18066063

RESUMO

Basal-like breast cancer (BBC) is a subtype of breast cancer with poor prognosis. Inherited mutations of BRCA1, a cancer susceptibility gene involved in double-strand DNA break (DSB) repair, lead to breast cancers that are nearly always of the BBC subtype; however, the precise molecular lesions and oncogenic consequences of BRCA1 dysfunction are poorly understood. Here we show that heterozygous inactivation of the tumor suppressor gene Pten leads to the formation of basal-like mammary tumors in mice, and that loss of PTEN expression is significantly associated with the BBC subtype in human sporadic and BRCA1-associated hereditary breast cancers. In addition, we identify frequent gross PTEN mutations, involving intragenic chromosome breaks, inversions, deletions and micro copy number aberrations, specifically in BRCA1-deficient tumors. These data provide an example of a specific and recurrent oncogenic consequence of BRCA1-dependent dysfunction in DNA repair and provide insight into the pathogenesis of BBC with therapeutic implications. These findings also argue that obtaining an accurate census of genes mutated in cancer will require a systematic examination for gross gene rearrangements, particularly in tumors with deficient DSB repair.


Assuntos
Neoplasias da Mama/genética , Reparo do DNA , Neoplasias Mamárias Animais/genética , PTEN Fosfo-Hidrolase/genética , Animais , Linhagem Celular Tumoral , Feminino , Genes BRCA1 , Genes Supressores de Tumor , Humanos , Camundongos , Mutação
14.
Proc Natl Acad Sci U S A ; 102(32): 11355-60, 2005 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-16051706

RESUMO

Molecular mechanisms underlying prostate and urothelial development remain unclear. This situation presents major limitations in identifying the cell type(s) and molecular events involved in the development of prostate and bladder cancer. It has been shown that mice lacking the basal cell marker p63 present several epithelial defects, including epidermis and prostate buds agenesis and urothelial abnormalities. Here, we use the p63-/- mouse as a tool to define cell lineages in the prostate epithelium and urothelium. By complementing p63-/- blastocysts with p63+/+ beta-galactosidase (beta-gal)-positive ES cells, we show that secretory cells of the prostate originate from p63-positive basal progenitor cells. Importantly, our urogenital sinus transplantation studies demonstrate that p63 prevents intestinal differentiation of the urogenital sinus endoderm and is therefore required to maintain commitment to the prostate cell lineage. Finally, in contrast with the prostate findings, analysis of the urothelium from rescued p63-/- chimeras shows that umbrella (superficial) cells can develop and be maintained independently from p63-positive basal and intermediate cells.


Assuntos
Diferenciação Celular/fisiologia , Linhagem da Célula/fisiologia , Fosfoproteínas/fisiologia , Próstata/citologia , Transativadores/fisiologia , Animais , Células Epiteliais/metabolismo , Células Epiteliais/fisiologia , Feminino , Histocitoquímica , Masculino , Camundongos , Camundongos Knockout , Próstata/embriologia , Células-Tronco/fisiologia , Quimeras de Transplante/embriologia , Urotélio/embriologia , beta-Galactosidase
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