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1.
Rev. Soc. Cardiol. Estado de Säo Paulo ; 29(Suppl. 2b): 147-147, Jun. 2019.
Artigo em Português | Sec. Est. Saúde SP, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1009438

RESUMO

INTRODUÇÃO: A maioria dos pacientes com doença de Chagas mostra perda do controle cardíaco parassimpático o que pode ser a causa de arritmias malignas e morte súbita. O conceito de tratar problemas cardíacos com bloqueio simpático existe desde que descobriu-se que a denervação simpática cardíaca esquerda reduziu a incidência de fibrilação ventricular (FV) em experimentos com cães. O bloqueio do gânglio estrelado evoluiu de denervação simpática e atualmente é aventado como uma importante terapia adjuvante no tratamento de tempestades elétricas. RELATO DE CASO: Paciente do sexo masculino, 50 anos, acompanhado em um serviço terciário de cardiologia devido a cardiomiopatia chagásica forma arritmogênica. Foi submetido a implante de cardiodesfibrilador implantável (CDI) em 2015 devido a episódio de taquicardia ventricular sustentada (TVS) induzida em estudo eletrofisiológico. Há 1 mês, paciente procura o serviço com queixa de dor torácica em queimação sendo admitido em TVS monomórfica com frequência de 130 bpm. Foi submetido a cardioverão química e elétrica com recorrência da taquicardia, a qual foi parcialmente controlada com terapias antitaquicardia do dispositivo. Optou-se pelo bloqueio do gânglio estrelado esquerdo com solução de bupivacaina e xylocaina, guiado por Ultrassom, e após 24 horas do procedimento evoluiu com apenas 1 episódio de TVS lenta revertida com ATP. Manteve-se assintomático sendo submetido a ablação epicárdica e endocárdica com mapeamento eletroanatômico 7 dias após. DISCUSSÃO: Tempestade elétrica pode ocorrer em até 20% de pacientes com CDI e está associada com morbidade e mortalidade significativas. Geralmente é acompanhada por um surto simpático frequentemente resistente a antiarrítmicos, terapia medicamentosa, necessitando de bloqueio simpático. Neste contexto, a denervação simpática cardíaca esquerda demonstrou reduzir a carga de choque de CDI em pequenas séries de pacientes com doença cardíaca estrutural e taquiarritmias recorrentes. O bloqueio do gânglio estrelado pode ser alcançado através da infusão de anestésico periganglionar e esta prática tende a estabilizar um paciente por tempo suficiente para realização de ablação por cateter. CONCLUSÃO: O bloqueio simpático do gânglio estrelado restaura o equilíbrio do sistema nervoso autonômico sendo uma alternativa de baixo risco para estabilização dos pacientes até a realização da terapia final. Infelizmente, ainda permanece subutilizado devido à falta de conhecimento e compreensão da eficácia e duração do efeito, além de ser necessário mais estudos em pacientes chagásicos. (AU)


Assuntos
Humanos , Doença de Chagas , Taquicardia Ventricular
2.
J Endocrinol Invest ; 39(10): 1095-103, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27180180

RESUMO

Type 2 diabetes (T2D) and obesity are the major public health problems. Substantial efforts have been made to define loci and variants contributing to the individual risk of these disorders. However, the overall risk explained by genetic variation is very modest. Epigenetics is one of the fastest growing research areas in biomedicine as changes in the epigenome are involved in many biological processes, impact on the risk for several complex diseases including diabetes and may explain susceptibility. In this review, we focus on the role of DNA methylation in contributing to the risk of T2D and obesity.


Assuntos
Diabetes Mellitus Tipo 2/genética , Epigênese Genética/genética , Obesidade/genética , Humanos
3.
Int J Obes (Lond) ; 40(6): 929-37, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26980478

RESUMO

BACKGROUND/OBJECTIVES: The genomic bases of the adipose tissue abnormalities induced by chronic positive calorie excess have been only partially elucidated. We adopted a genome-wide approach to directly test whether long-term high-fat diet (HFD) exposure affects the DNA methylation profile of the mouse adipose tissue and to identify the functional consequences of these changes. SUBJECTS/METHODS: We have used epididymal fat of mice fed either high-fat (HFD) or regular chow (STD) diet for 5 months and performed genome-wide DNA methylation analyses by methylated DNA immunoprecipitation sequencing (MeDIP-seq). Mouse Homeobox (Hox) Gene DNA Methylation PCR, RT-qPCR and bisulphite sequencing analyses were then performed. RESULTS: Mice fed the HFD progressively expanded their adipose mass accompanied by a significant decrease in glucose tolerance (P<0.001) and insulin sensitivity (P<0.05). MeDIP-seq data analysis revealed a uniform distribution of differentially methylated regions (DMR) through the entire adipocyte genome, with a higher number of hypermethylated regions in HFD mice (P<0.005). This different methylation profile was accompanied by increased expression of the Dnmt3a DNA methyltransferase (Dnmt; P<0.05) and the methyl-CpG-binding domain protein Mbd3 (P<0.05) genes in HFD mice. Gene ontology analysis revealed that, in the HFD-treated mice, the Hox family of development genes was highly enriched in differentially methylated genes (P=0.008). To validate this finding, Hoxa5, which is implicated in fat tissue differentiation and remodeling, has been selected and analyzed by bisulphite sequencing, confirming hypermethylation in the adipose tissue from the HFD mice. Hoxa5 hypermethylation was associated with downregulation of Hoxa5 mRNA and protein expression. Feeding animals previously exposed to the HFD with a standard chow diet for two further months improved the metabolic phenotype of the animals, accompanied by return of Hoxa5 methylation and expression levels (P<0.05) to values similar to those of the control mice maintained under standard chow. CONCLUSIONS: HFD induces adipose tissue abnormalities accompanied by epigenetic changes at the Hoxa5 adipose tissue remodeling gene.


Assuntos
Tecido Adiposo/metabolismo , Metilação de DNA , Dieta Hiperlipídica , Regulação para Baixo , Proteínas de Homeodomínio/genética , Fosfoproteínas/genética , Transcrição Gênica , Animais , Modelos Animais de Doenças , Epigênese Genética , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/genética , Fatores de Transcrição
4.
Sleep Breath ; 20(4): 1175-1183, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27026417

RESUMO

PURPOSE: Obesity is one of the main predisposing factors for obstructive sleep apnea (OSA) hypopnea syndrome. It has been described that body mass index (BMI) influences the accuracy of oxygen desaturation index (ODI) for the diagnosis of OSA by polysomnography (PSG). We analyzed the relationship between traditional indicators: apnea-hypopnea index (AHI) and ODI in a population at high risk for OSA, by respiratory polygraphy (RP) and PSG. METHODS: This is a retrospective study of 1898 patients with suspicion of OSA, from which 1053 underwent RP and 582 underwent PSG with OSA. We compared results considering gender, age, and degree of obesity. RESULTS: This study included 1333 records of patients with OSA-more than 80 % of whom were overweight or obese. We observed that AHI and ODI increased progressively with obesity grade and said increase was associated with BMI only in men. The evaluation of the agreement between AHI and ODI found a difference between normal weight and obese patients, regardless of gender. CONCLUSIONS: Study findings contribute to understand the role of oximetry in the diagnosis of OSA in obese patients. Our results were observed using full PSG and a simplified home method. The correlation between these indicators could improve our clinical interpretation of OSA severity among obese patients when abbreviated tests are used.


Assuntos
Obesidade/sangue , Sobrepeso/sangue , Oxigênio/sangue , Polissonografia , Apneia Obstrutiva do Sono/sangue , Adulto , Idoso , Índice de Massa Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Sobrepeso/complicações , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais , Apneia Obstrutiva do Sono/etiologia , Estatística como Assunto
5.
Br J Cancer ; 113(6): 970-8, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26325105

RESUMO

BACKGROUND: The transforming growth factor-beta (TGF- ß) pathway has been implicated in proliferation, migration and invasion of various cancers. Endoglin is a TGF-ß accessory receptor that modulates signalling. We identified Endoglin as an epigenetically silenced tumour-suppressor gene in lung cancer by means of a genome-wide screening approach, then sought to characterise its effect on lung cancer progression. METHODS: Methylation microarray and RNA sequencing were carried out on lung cancer cell lines. Epigenetic silencing of Endoglin was confirmed by methylation and expression analyses. An expression vector and a 20-gene expression panel were used to evaluate Endoglin function. Pyrosequencing was carried out on two independent cohorts comprising 112 and 202 NSCLC cases, respectively, and the impact of Endoglin methylation on overall survival (OS) was evaluated. RESULTS: Methylation in the promoter region resulted in silencing of Endoglin, which could be reactivated by demethylation. Increased invasion coupled with altered EMT marker expression was observed in cell lines with an epithelial-like, but not those with a mesenchymal-like, profile when Endoglin was absent. Methylation was associated with decreased OS in stage I but not in stages II-III disease. CONCLUSIONS: We show that Endoglin is a common target of epigenetic silencing in lung cancer. We reveal a link between Endoglin silencing and EMT progression that might be associated with decreased survival in stage I disease.


Assuntos
Antígenos CD/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Inativação Gênica , Genes Supressores de Tumor , Neoplasias Pulmonares/genética , Receptores de Superfície Celular/genética , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Progressão da Doença , Regulação para Baixo , Endoglina , Estudo de Associação Genômica Ampla , Humanos , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Metilação , Regiões Promotoras Genéticas , Análise Serial de Proteínas , Análise de Sequência de DNA/métodos
6.
Cell Death Dis ; 4: e458, 2013 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-23328665

RESUMO

Arginine deprivation, either by nutritional starvation or exposure to ADI-PEG20, induces adaptive transcriptional upregulation of ASS1 and ASL in glioblastoma multiforme ex vivo cultures and cell lines. This adaptive transcriptional upregulation is blocked by neoplasia-specific CpG island methylation in either gene, causing arginine auxotrophy and cell death. In cells with methylated ASS1 or ASL CpG islands, ADI-PEG20 initially induces a protective autophagic response, but abrogation of this by chloroquine accelerates and potentiates cytotoxicity. Concomitant methylation in the CpG islands of both ASS1 and ASL, observed in a subset of cases, confers hypersensitivity to ADI-PEG20. Cancer stem cells positive for CD133 and methylation in the ASL CpG island retain sensitivity to ADI-PEG20. Our results show for the first time that epigenetic changes occur in both of the two key genes of arginine biosynthesis in human cancer and confer sensitivity to therapeutic arginine deprivation. We demonstrate that methylation status of the CpG islands, rather than expression levels per se of the genes, predicts sensitivity to arginine deprivation. Our results suggest a novel therapeutic strategy for this invariably fatal central nervous system neoplasm for which we have identified robust biomarkers and which overcomes the limitations to conventional chemotherapy imposed by the blood/brain barrier.


Assuntos
Apoptose , Argininossuccinato Liase/metabolismo , Argininossuccinato Sintase/metabolismo , Autofagia , Epigenômica , Arginina/metabolismo , Argininossuccinato Liase/genética , Argininossuccinato Sintase/antagonistas & inibidores , Argininossuccinato Sintase/genética , Azacitidina/análogos & derivados , Azacitidina/farmacologia , Neoplasias do Sistema Nervoso Central/metabolismo , Neoplasias do Sistema Nervoso Central/patologia , Cloroquina/toxicidade , Ilhas de CpG , Metilação de DNA/efeitos dos fármacos , Decitabina , Glioblastoma/metabolismo , Glioblastoma/patologia , Humanos , Hidrolases/farmacologia , Polietilenoglicóis/farmacologia , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Estilbenos/farmacologia , Células Tumorais Cultivadas , Regulação para Cima/efeitos dos fármacos
7.
G Chir ; 33(10): 318-23, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23095559

RESUMO

INTRODUCTION: Thymomas (THs) are rare epithelial tumors of the thymus gland. In this study we report our personal experience in the management and surgical treatment of THs. CASE REPORTS: We report two clinical cases treated with combined therapy (surgery followed by adjuvant therapy). RESULTS: Total transternal thymectomy was performed in both patients. The post-operative course was uneventful. The patients received adjuvant radiotherapy and chemotherapy. No relapse has been observed during follow-up. DISCUSSION: THs are usually slowly growing tumors with similar incidence in both sexes. They occur through a wide age range, with a peak in the fifth and sixth decades. Distinctive features reminiscent of the normal thymus make the pathologic diagnosis of THs easy in most cases. Malignant behaviour is indicated by microscopic or macroscopic invasion of the tumor capsule or surrounding organs or by the presence of metastases. Although there is no standardized staging system for thymoma, the one proposed by Masaoka is commonly employed. Total thymectomy is the procedure of choice, even for encapsulated tumors, with carefully exploration of the mediastinum for evidence of ectopic thymic tissue or local invasion. CONCLUSIONS: Despite an indolent course and a cytologically bland appearance, all thymic tumors can manifest a malignant behavior. Surgery continues to be the mainstay of treatment, and the ability to achieve complete resection seems to be the most important prognostic factor. Multimodality treatment involving postoperative chemotherapy and radiotherapy appears to increase the rate of complete resection and improves survival in advanced THs.


Assuntos
Timoma/cirurgia , Neoplasias do Timo/cirurgia , Idoso , Humanos , Masculino , Adulto Jovem
8.
Br J Cancer ; 107(8): 1423-32, 2012 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-22955849

RESUMO

BACKGROUND: Prolyl hydroxylation is a post-translational modification that affects the structure, stability and function of proteins including collagen by catalysing hydroxylation of proline to hydroxyproline through action of collagen prolyl hydroxylases3 (C-P3H) and 4 (C-P4H). Three C-P3Hs (nomenclature was amended according to approval by the HGNC symbols and names at http://www.genenames.org/ and Entrez database at http://www.ncbi.nlm.nih.gov/gene) leucineproline-enriched proteoglycan (leprecan) 1 (Lepre1), leprecan-like 1 (Leprel1), leprecan-like 2 (Leprel2) and two paralogs Cartilage-Related Protein (CRTAP) and leprecan-like 4 (Leprel4) are found in humans. The C-P4Hs are tetrameric proteins comprising a variable α subunit, encoded by the P4HA1, P4HA2 and P4HA3 genes and a constant ß subunit encoded by P4HB. METHODS: We used RT-PCR, qPCR, pyrosequencing, methylation-specific PCR, western blotting and immunohistochemistry to investigate expression and regulation of the C-P3H and C-P4H genes in B lymphomas and normal bone marrow. RESULTS: C-P3H and C-P4H are downregulated in lymphoma. Down-regulation is associated with methylation in the CpG islands and is detected in almost all common types of B-cell lymphoma, but the CpG islands are unmethylated or methylated at lower levels in DNA isolated from normal bone marrow and lymphoblastoid cell lines. Methylation of multiple C-P3H and C-P4H genes is present in some lymphomas, particularly Burkitt's lymphoma. CONCLUSIONS: Methylation of C-P3H and C-P4H is common in B lymphomas and may have utility in differentiating disease subtypes.


Assuntos
Colágeno/genética , Linfoma de Células B/genética , Pró-Colágeno-Prolina Dioxigenase/genética , Linhagem Celular Tumoral , Colágeno/metabolismo , Ilhas de CpG/genética , Regulação da Expressão Gênica , Inativação Gênica , Humanos , Linfoma de Células B/metabolismo , Metilação , Pró-Colágeno-Prolina Dioxigenase/metabolismo
9.
G Chir ; 33(6-7): 229-33, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22958805

RESUMO

Introduction. Synchronous occurrence of pulmonary and hepatic hydatid cysts is an uncommon manifestation of hydatid disease that is observed in less than 10% of cases. We report a rare case of bilateral lung (with bronchial fistula) and liver cyst, surgically treated after medical therapy. Case report. A 44-year-old housewife reporting fever, anorexia and fatigue that had been present for the previous 20 days received diagnosis of bilateral lung and liver hydatid cyst. Because of the dimensions of right lung cyst and the successive bronchial fistolization, we proceeded to three-stage operation of two thoracotomies and a laparotomy to control the risk of further rupture. After surgery, all post-operatives were uneventful. Complete resolution of the therapy with no evidence of recurrence at 2 years follow-up. Conclusion. We emphasize the need to search for additional hydatids in patients who present with either pulmonary or liver hydatids. The simultaneous treatment of liver and lung should be reserved to patients in good conditions; in all other cases, especially when one cyst is more symptomatic than the others or has more risk of rupture, we prefer to treat single cyst.


Assuntos
Equinococose Hepática/complicações , Equinococose Pulmonar/complicações , Adulto , Feminino , Humanos
10.
Br J Cancer ; 107(4): 732-8, 2012 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-22782348

RESUMO

BACKGROUND: The CCAAT/enhancer binding protein delta (CEBPδ) is a member of a highly conserved family of basic region leucine zipper transcription factors. It has properties consistent with a tumour suppressor; however, other data suggest that CEBPδ may be involved in the metastatic process. METHODS: We analysed the expression of CEBPδ and the methylation status of the CpG island in human breast cancer cell lines, in 107 archival cases of primary breast cancer and in two series of metastatic breast cancers using qPCR and pyrosequencing. RESULTS: Expression of CEBPδ is downregulated in primary breast cancer by site-specific methylation in the CEBPδ CpG island. Expression is also downregulated in 50% of cases during progression from primary carcinoma to metastatic lesions. The CEBPδ CpG island is methylated in 81% metastatic breast cancer lesions, while methylation in the CEBPδ CpG island in primary cancers is associated with increased risk of relapse and metastasis. CONCLUSION: CCAAT/enhancer binding protein delta CpG island methylation is associated with metastasis in breast cancer. Detection of methylated CEBPδ genomic DNA may have utility as an epigenetic biomarker of primary breast carcinomas at increased risk of relapse and metastasis.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Proteína delta de Ligação ao Facilitador CCAAT/genética , Ilhas de CpG/genética , Metilação de DNA , Metástase Neoplásica/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Regulação para Baixo , Feminino , Humanos , Pessoa de Meia-Idade , Prognóstico , Recidiva
11.
Br J Cancer ; 107(1): 75-83, 2012 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-22653144

RESUMO

BACKGROUND: Relapse risk assessment and individual treatment recommendations remain suboptimal for breast cancer patients. In the light of existing preclinical and clinical data, we studied NT5E (5'-nucleotidase, ecto) expression and NT5E CpG island methylation in breast cancer. METHODS: We used RT-PCR, qPCR, methylation-specific PCR and pyrosequencing to analyse NT5E in breast carcinoma cell lines and primary and breast carcinomas. RESULTS: NT5E CpG island methylation was inversely associated with NT5E expression in breast carcinoma cell lines. In clinical series, patients whose primary tumours had NT5E CpG island methylation were less likely to develop metastasis (P=0.003, OR=0.34, 95% CI: 0.17-0.69). In 3/4 paired samples, NT5E was methylated in primary tumours and demethylated in CNS metastases. Patients progressing to non-visceral as compared with visceral metastases were more likely to have NT5E CpG island methylation in primary tumours (P=0.01, OR=11.8). Patients with tumours lacking detectable methylation had shorter disease-free survival (DFS) (P=0.001, HR=2.7) and overall survival (OS) (P=0.001, HR=3). The favourable prognostic value of NT5E methylation was confirmed in oestrogen receptor negative (P=0.011, HR=3.27, 95% CI: 1.31-8.12) and in triple negative cases (P=0.004; HR=6.2, 95% CI: 1.9-20). Moreover, we observed a more favourable outcome to adjuvant chemotherapy in patients whose tumours were positive for NT5E CpG island methylation: DFS (P=0.0016, HR=5.1, 95% CI: 1.8-14.37) and OS (P=0.0005, HR=7.4, 95% CI: 2.416-23.08). CONCLUSION: NT5E CpG island methylation is a promising breast cancer biomarker.


Assuntos
5'-Nucleotidase/genética , Biomarcadores Tumorais/análise , Neoplasias da Mama/genética , Metilação de DNA , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Ilhas de CpG , Intervalo Livre de Doença , Feminino , Proteínas Ligadas por GPI/genética , Inativação Gênica , Humanos , Metástase Neoplásica/genética , Prognóstico , Regiões Promotoras Genéticas
12.
Br J Cancer ; 107(2): 375-81, 2012 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-22644305

RESUMO

BACKGROUND: Calcium is an important intracellular messenger that mediates many biological processes that are relevant to the malignant process. Calcium ion channels are key in controlling the intracellular calcium, and little is known about their role in human cancer. METHODS: We used qPCR and pyrosequencing to investigate expression and epigenetic regulation of the calcium channel regulatory subunit α(2)δ-3 (CACNA2D3) in breast cancer cell lines, primary cancers and metastatic lesions. RESULTS: Expression of CACNA2D3 mRNA is regulated in breast cancer cell lines by methylation in the CpG island located in the 5' regulatory region of the gene. Expression is upregulated by azacytidine (AZA) in cells with CpG island methylation but unaffected in cells lacking methylation. In primary breast carcinomas, methylation is more common in cancers, which subsequently relapse with loco-regional and, particularly, visceral metastatic disease in both oestrogen receptor-α (ER)-positive and -negative cases. Furthermore, CACNA2D3 CpG island is frequently methylated in breast cancer that has metastasised to the central nervous system. CONCLUSION: Methylation-dependent transcriptional silencing of CACNA2D3 may contribute to the metastatic phenotype of breast cancer. Analysis of methylation in the CACNA2D3 CpG island may have potential as a biomarker for risk of development of metastatic disease.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Canais de Cálcio/genética , Canais de Cálcio/metabolismo , Metilação de DNA , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Neoplasias da Mama/patologia , Cálcio/metabolismo , Linhagem Celular Tumoral , Ilhas de CpG/genética , Feminino , Humanos , Células MCF-7 , Metástase Neoplásica , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/metabolismo , RNA Mensageiro/genética , Sequências Reguladoras de Ácido Nucleico
13.
Br J Cancer ; 106(8): 1446-52, 2012 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-22454080

RESUMO

BACKGROUND: Novel prognostic biomarkers and therapeutic strategies are urgently required for malignant melanoma. Ecto-5-prime-nucleotidase (NT5E; CD73) overexpression has been reported in several human cancers. The mechanism(s) underlying deregulated expression and the clinical consequences of changes in expression are not known. METHODS: We used RT-PCR, qPCR, methylation-specific PCR and pyrosequencing to analyse expression and regulation of NT5E in malignant melanoma cell lines and primary and metastatic melanomas. RESULTS: NT5E is subject to epigenetic regulation in melanoma. NT5E mRNA is downregulated by methylation-dependent transcriptional silencing in the melanoma cell lines SKMel2, SKMel23, WM35, Mel501, Mel505 and C81-61 and expression is reactivated by azacytidine. In contrast, the CpG island is unmethylated and the gene expressed in cultured normal melanocytes. In clinical cases of melanoma, methylation in the NT5E CpG island occurs in both primary and metastatic melanomas and correlates with transcriptional downregulation of NT5E mRNA. Relapse with metastatic disease, particularly to the visceral sites and brain, is more common in primary melanomas lacking NT5E methylation. Primary melanomas with methylation in NT5E show limited metastatic potential or more commonly metastasise predominantly to nodal sites rather than viscera and brain (P=0.01). CONCLUSION: Deregulation of NT5E expression in melanoma occurs via epigenetic changes in the NT5E CpG island. Confirmation of our results in larger clinical series would support the candidacy of NT5E as a clinical biomarker in melanoma, which could be applied in both primary and relapsed disease. Inhibition of NT5E may have therapeutic potential in melanoma, particularly in patients with more aggressive disease metastatic to viscera or the brain.


Assuntos
5'-Nucleotidase/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/secundário , Epigênese Genética/genética , Melanoma/genética , Melanoma/patologia , 5'-Nucleotidase/metabolismo , Linhagem Celular Tumoral , Ilhas de CpG/genética , Metilação de DNA/genética , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/metabolismo , Inativação Gênica , Humanos , Especificidade de Órgãos , Reação em Cadeia da Polimerase , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcrição Gênica/genética
14.
Diabetologia ; 55(1): 141-53, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22006246

RESUMO

AIMS/HYPOTHESIS: Beta cell failure is caused by loss of cell mass, mostly by apoptosis, but also by simple dysfunction (decline of glucose-stimulated insulin secretion, downregulation of specific gene expression). Apoptosis and dysfunction are caused, at least in part, by lipoglucotoxicity. The mechanisms implicated are oxidative stress, increase in the hexosamine biosynthetic pathway (HBP) flux and endoplasmic reticulum (ER) stress. Oxidative stress plays a role in glucotoxicity-induced beta cell dedifferentiation, while glucotoxicity-induced ER stress has been mostly linked to beta cell apoptosis. We sought to clarify whether ER stress caused by increased HBP flux participates in a dedifferentiating response of beta cells, in the absence of relevant apoptosis. METHODS: We used INS-1E cells and murine islets. We analysed the unfolded protein response and the expression profile of beta cells by real-time RT-PCR and western blot. The signal transmission pathway elicited by ER stress was investigated by real-time RT-PCR and immunofluorescence. RESULTS: Glucosamine and high glucose induced ER stress, but did not decrease cell viability in INS-1E cells. ER stress caused dedifferentiation of beta cells, as shown by downregulation of beta cell markers and of the transcription factor, pancreatic and duodenal homeobox 1. Glucose-stimulated insulin secretion was inhibited. These effects were prevented by the chemical chaperone, 4-phenyl butyric acid. The extracellular signal-regulated kinase (ERK) signal transmission pathway was implicated, since its inhibition prevented the effects induced by glucosamine and high glucose. CONCLUSIONS/INTERPRETATION: Glucotoxic ER stress dedifferentiates beta cells, in the absence of apoptosis, through a transcriptional response. These effects are mediated by the activation of ERK1/2.


Assuntos
Desdiferenciação Celular , Glucosamina/metabolismo , Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Sistema de Sinalização das MAP Quinases , Animais , Desdiferenciação Celular/efeitos dos fármacos , Linhagem Celular , Células Clonais , Regulação para Baixo/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Insulina/genética , Secreção de Insulina , Ilhotas Pancreáticas/citologia , Ilhotas Pancreáticas/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Fenilbutiratos/farmacologia , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , RNA Mensageiro/metabolismo , Ratos , Transativadores/genética , Transativadores/metabolismo , Resposta a Proteínas não Dobradas/efeitos dos fármacos
15.
Br J Cancer ; 106(2): 397-404, 2012 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-22187033

RESUMO

BACKGROUND: Brain metastasis from breast cancer is usually associated with a poor prognosis and early death. Alteration of p53 may contribute to malignant progression by abrogation of apoptosis induced by oncogene activation and by acquisition of gain-of-function properties, which promote tumour aggression. Mutation in TP53 occurs at high frequency in carcinomas of the lung and gastro-intestinal tract, but is much less frequent, at 25%, in primary breast cancer. The frequency of TP53 alteration in the central nervous system (CNS) metastatic breast cancer is not known. METHODS: In all, 23 cases of histologically confirmed CNS metastatic breast cancer were identified and the coding sequence of TP53 determined. TP53 was also sequenced in two control series of primary breast carcinomas from independent clinical centres. RESULTS: We demonstrate a strikingly high frequency of TP53 mutation in the CNS metastatic lesions with an over-representation of complex mutations (non-sense/deletions/insertions). Complex mutations occur in metastatic lesions in both triple-negative breast cancer and hormone receptor/HER2-positive cases. Analysis of paired primary carcinomas and brain metastatic lesions revealed evidence for both clonal selection and generation of new mutations (missense and complex) in progression from a primary breast carcinoma to brain metastasis. CONCLUSION: Mutation in TP53 is the most common genetic alteration reported during metastasis to the brain in breast cancer.


Assuntos
Neoplasias da Mama/genética , Neoplasias do Sistema Nervoso Central/secundário , Genes p53 , Mutação , Sequência de Bases , Neoplasias da Mama/patologia , Neoplasias do Sistema Nervoso Central/genética , Primers do DNA , Feminino , Humanos
16.
G Chir ; 32(5): 251-4, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21619776

RESUMO

INTRODUCTION: Non-recurrence and variations in ascending course of the recurrent laryngeal nerve (RLN) represent a risk factor for nerve injuries during thyroid surgery. Non-recurrent laryngeal nerve (NRLN) coexisting to recurrent nerve branch is a rare anatomic anomaly. It could be a cause of nerve injuries during thyroidectomy. A systematic intraoperative nerve identification may allow an effectiveness prevention of iatrogenic injuries. CASE REPORT: We report one case of a young woman underwent to total thyroidectomy (TT) for papillary thyroid carcinoma (PTC) where we found a rare variation of the right inferior laryngeal nerve anatomy. We identified both right laryngeal nerve structures before completing thyroidectomy avoiding possible nerve damage. The postoperative course was without complications. DISCUSSION: Iatrogenic injury of RLN is one of the most serious complication in thyroid surgery. Several risk factors favouring this complication were found as the presence of anatomic variations of the inferior laryngeal nerve. Identification of a normal caliber recurrent nerve can allow the surgeon to complete the thyroid excision; diversely, in case of a smaller caliber nerve in the usual recurrent course, a careful dissection should be continued to demonstrate a possible merger with ipsilateral non-recurrent nerve. CONCLUSIONS: The aim of this paper is to report a rare case of NRLN associated to a smaller caliber branch of RNL. We emphasize that careful dissection and intimate knowledge of normal and anomaly anatomy allow for avoidance of nerve injury during surgery in the neck.


Assuntos
Nervo Laríngeo Recorrente/anormalidades , Nervo Laríngeo Recorrente/anatomia & histologia , Tireoidectomia , Adulto , Feminino , Humanos
17.
G Chir ; 32(3): 113-7, 2011 Mar.
Artigo em Italiano | MEDLINE | ID: mdl-21453588

RESUMO

INTRODUCTION: Bleeding esophageal varices is the most serious complication of the portal hypertension, and the greater cause of dead (25% of the patients). The survival after esophageal varices bleeding depends in wide part from the swiftness and effectiveness of hemostasis and from the degree of functional liver reserve. Aim of our manuscript is to report our experience about hemostasis bleeding esophageal varices with endoscopic rubber band ligation. PATIENTS AND METHODS: From January 1999 to January 2008 we performed 302 esofagogastroduodenoscopy (EGDS) for esophageal varices bleeding (M: F ratio = 1.4:1, mean age 56.4 years, 62% of cases with HCV-related cirrhosis, 29% alcoholic cirrhosis and 9% cryptogenic cirrhosis; 20% suffered from chronic renal failure, 15% diabetes mellitus, 10% hepatocellular carcinoma on cirrhosis, 5% systemic encephalopathy and 1% AIDS). RESULTS; All patients were treated within 6 hours after the first reported episode of haematemesis and all received beta-blocker therapy after the episode. In the first phase of our experience were used rechargeable elastic ligator and then multibyte, even in combination with polidocanol sclerotherapy (8%) or injection of cyanoacrylate (5%). The best results were achieved with band ligation, in terms of primitive haemostasis, rebleeding, (3%), intraoperative mortality (1%) and 6 weeks mortality (1%). CONCLUSION: To date, no single method applicable to all patients with bleeding esophageal varices, but endoscopic rubber band ligation is currently considered the first-line treatment of proper multidisciplinary approach to the patient, both during the acute event than prevention of rebleeding, because it is an effective, safe and repeatable, in experienced hands.


Assuntos
Varizes Esofágicas e Gástricas/cirurgia , Esofagoscopia , Hemorragia Gastrointestinal/cirurgia , Técnicas Hemostáticas , Varizes Esofágicas e Gástricas/complicações , Feminino , Hemorragia Gastrointestinal/etiologia , Humanos , Ligadura/métodos , Masculino , Pessoa de Meia-Idade , Borracha
18.
Ann Oncol ; 22(3): 712-717, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20810547

RESUMO

BACKGROUND: Intensification of chemoradiation for advanced head and neck squamous cell carcinoma (HNSCC) is unlikely due to toxicity. Cetuximab combined either with radiotherapy or with chemotherapy showed favourable toxic profile with positive results in both combinations. Therefore, cetuximab could intensify chemoradiation without worsening toxicity. We conducted a phase II study of chemoradiation and cetuximab. PATIENTS AND METHODS: Eligible patients had stage III-IV M0 HNSCC. Treatment consisted of three cycles of cisplatin (20 mg/m(2)/day × 5 days) and fluorouracil (200 mg/m(2)/day × 5 days) rapidly alternated to three split courses of radiotherapy up to 70 Gy and concurrent weekly cetuximab. The primary end point of the study was complete response (CR) rate. Secondary end points were toxicity, progression-free survival (PFS) and overall survival (OS). RESULTS: Fourty-five patients were enrolled: median age was 56 years, 38 had stage IV disease and 40 nodal involvement. CR occurred in 32 patients (71%). PFS and OS was 21+ months and 32.6+, respectively. Acute grade 3-4 toxic effects were in the expected range, but grade 3 radiodermatitis occurred in 33 patients. CONCLUSIONS: The combination of cetuximab, cisplatin, fluorouracil and radiotherapy leads to a very high proportion of CR and it is feasible with toxic effects similar to those expected by radiochemotherapy. The only unexpected toxicity was skin toxicity: grade 3 radiodermatitis occurred in 73% of the patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Adulto , Idoso , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma de Células Escamosas/mortalidade , Cetuximab , Cisplatino/administração & dosagem , Terapia Combinada , Feminino , Neoplasias de Cabeça e Pescoço/mortalidade , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Radiodermite/induzido quimicamente , Resultado do Tratamento , Adulto Jovem
19.
ISRN Otolaryngol ; 2011: 931813, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-23724261

RESUMO

Head and neck cancer is a complex disorder that includes mostly squamous cell carcinomas that can develop in the throat, larynx, nose, sinuses, and mouth. Etiopathogenesis is due to tobacco and alcohol consumption and to infection by human papillomavirus (HPV) type 16/18. Tumors often develop within preneoplastic fields of genetically altered cells. Most head and neck cancers result from multistep accumulation of genetic alterationsm resulting in clonal outgrowth of transformed cells. These DNA changes are caused by a variety of mechanisms like endogenous mutations and exogenous mutations. Dysregulated molecular pathway includes alterations of critical inhibitor of cyclin CDK complexes, inactivating mutations of p53 gene, and activation of oncogenes and growth factors. This paper attempts to review the role of p53 and MDM2 genetic aberrations and pathways in head and neck cancer.

20.
Diabetologia ; 53(7): 1482-92, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20396999

RESUMO

AIMS/HYPOTHESIS: Overexpression of PED (also known as PEA15) determines insulin resistance and impaired insulin secretion and may contribute to progression toward type 2 diabetes. Recently, we found that the transcription factor hepatocyte nuclear factor (HNF)-4alpha binds to PED promoter and represses its transcription. However, the molecular details responsible for regulation of PED gene remain unclear. METHODS: Here we used gain and loss of function approaches to investigate the hypothesis that HNF-4alpha controls chromatin remodelling at the PED promoter in human cell lines. RESULTS: HNF-4alpha production and binding induce chromatin remodelling at the -250 to 50 region of PED, indicating that remodelling is limited to two nucleosomes located at the proximal promoter. Chromatin immunoprecipitation assays also revealed concomitant HNF-4alpha-induced deacetylation of histone H3 at Lys9 and Lys14, and increased dimethylation of histone H3 at Lys9. The latter was followed by reduction of histone H3 Lys4 dimethylation. HNF-4alpha was also shown to target the histone deacetylase complex associated with silencing mediator of retinoic acid and thyroid hormone receptor, both at the PED promoter, and at GRB14 and USP21 regulatory regions, leading to a reduction of mRNA levels. Moreover, HNF-4alpha silencing and PED overexpression were accompanied by a significant reduction of hepatic glycogen content. CONCLUSIONS/INTERPRETATION: These results show that HNF-4alpha serves as a scaffold protein for histone deacetylase activities, thereby inhibiting liver expression of genes including PED. Dysregulation of these mechanisms may lead to upregulation of the PED gene in type 2 diabetes.


Assuntos
Epigênese Genética/fisiologia , Fator 4 Nuclear de Hepatócito/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Fosfoproteínas/metabolismo , Acetilação , Animais , Proteínas Reguladoras de Apoptose , Western Blotting , Montagem e Desmontagem da Cromatina/genética , Montagem e Desmontagem da Cromatina/fisiologia , Imunoprecipitação da Cromatina , Epigênese Genética/genética , Células Hep G2 , Fator 4 Nuclear de Hepatócito/genética , Histonas/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Camundongos , Camundongos Transgênicos , Nucleossomos/genética , Fosfoproteínas/genética , Regiões Promotoras Genéticas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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