Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Clin Cancer Res ; 27(2): 504-512, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33082214

RESUMO

PURPOSE: Women with hormone receptor-positive early breast cancers have a persistent risk of relapse and biomarkers for late recurrence are needed. We sought to identify tumor genomic aberrations associated with increased late-recurrence risk. EXPERIMENTAL DESIGN: In a secondary analysis of Study of Letrozole Extension trial, a case-cohort-like sampling selected 598 primary breast cancers for targeted next-generation sequencing analysis of gene mutations and copy-number gains (CNGs). Correlations of genomic aberrations with clinicopathologic factors and breast and distant recurrence-free intervals (BCFIs and DRFIs) were analyzed using weighted Cox models. RESULTS: Analysis of mutations and CNGs was successfully performed for 403 and 350 samples, including 148 and 134 patients with breast cancer recurrences (median follow-up time, 5.2 years), respectively. The most frequent alterations were PIK3CA mutations (42%) and CNGs of CCND1 (15%), ERBB2 (10%), FGFR1 (8%), and MYC (8%). PIK3CA mutations and MYC CNGs were associated with lower (P = 0.03) and higher (P = 0.004) tumor grade, respectively; a higher Ki-67 was seen in tumor with CCND1, ERBB2, and MYC CNGs (P = 0.01, P < 0.001, and P = 0.03, respectively). FGFR1 CNG was associated with an increased risk of late events in univariate analyses [17/29 patients; BCFI: HR, 3.2; 95% confidence interval (CI), 1.48-6.92; P = 0.003 and DRFI: HR, 3.5; 95% CI, 1.61-7.75; P = 0.002) and in multivariable models adjusted for clinicopathologic factors. CONCLUSIONS: Postmenopausal women with hormone receptor-positive early breast cancer harboring FGFR1 CNG had an increased risk of late recurrence despite extended therapy. FGFR1 CNG may represent a useful prognostic biomarker for late recurrence and a therapeutic target.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Letrozol/uso terapêutico , Pós-Menopausa , Receptores de Estrogênio/metabolismo , Idoso , Antineoplásicos/uso terapêutico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Aberrações Cromossômicas , Feminino , Predisposição Genética para Doença/genética , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Mutação , Recidiva Local de Neoplasia , Polimorfismo de Nucleotídeo Único , Resultado do Tratamento
2.
J Immunol Res ; 2015: 981328, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26525279

RESUMO

Helicobacter pylori colonizes the gastric mucosa of at least half of the human population, causing a worldwide infection that appears in early childhood and if not treated, it can persist for life. The presence of symptoms and their severity depend on bacterial components, host susceptibility, and environmental factors, which allow H. pylori to switch between commensalism and pathogenicity. H. pylori-driven interactions with the host immune system underlie the persistence of the infection in humans, since the bacterium is able to interfere with the activity of innate and adaptive immune cells, reducing the inflammatory response in its favour. Gastritis due to H. pylori results from a complex interaction between several T cell subsets. In particular, H. pylori is known to induce a T helper (Th)1/Th17 cell response-driven gastritis, whose impaired modulation caused by the bacterium is thought to sustain the ongoing inflammatory condition and the unsuccessful clearing of the infection. In this review we discuss the current findings underlying the mechanisms implemented by H. pylori to alter the T helper lymphocyte proliferation, thus facilitating the development of chronic infections and allowing the survival of the bacterium in the human host.


Assuntos
Infecções por Helicobacter/imunologia , Helicobacter pylori/imunologia , Interações Hospedeiro-Patógeno/imunologia , Subpopulações de Linfócitos T/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Animais , Infecções por Helicobacter/metabolismo , Infecções por Helicobacter/microbiologia , Helicobacter pylori/metabolismo , Helicobacter pylori/patogenicidade , Humanos , Tolerância Imunológica , Imunidade Celular , Imunomodulação , Transdução de Sinais , Subpopulações de Linfócitos T/metabolismo , Linfócitos T Auxiliares-Indutores/metabolismo
3.
Onco Targets Ther ; 8: 2535-43, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26396529

RESUMO

Cancer immunotherapy is now recognized to be fundamental in modern oncology, because immune system recruitment may represent a powerful and innovative strategy in cancer therapy. Pembrolizumab, a highly selective humanized monoclonal antibody directly blocking the interaction between programmed cell death-1 expressed by tumor-associated T-cells and its ligand programmed cell death-L1 present on tumor and stromal cells, was recently approved by US Food and Drug Administration for the treatment of patients with unresectable or metastatic melanoma and disease progression upon ipilimumab and BRAF inhibitor. This review will focus on the clinical development and use of pembrolizumab in the clinical practice and in the management of advanced melanoma.

4.
Helicobacter ; 20(1): 41-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25308308

RESUMO

BACKGROUND: Indoleamine 2,3 dioxygenase (IDO) interferes with immune responses. Host immune response against Helicobacter pylori is involved in the persistence of the infection and its related diseases. AIM: To investigate the role of IDO in the regulation of Th1/Th2 and Th17 pathways in H. pylori infection. METHODS: Gastric biopsy samples were taken from 42 patients who underwent endoscopy and evaluated for the expression of IDO by Western blotting. Gastritis was assessed by the Sydney system score. In a subgroup of patients, biopsies were treated with the IDO inhibitor 1-methyl-L-tryptophan and the expression of interferon-γ (IFN-γ) mRNA and that of T-bet, interleukin-17 (IL-17), and IL-4 determined by real-time PCR and Western blotting, respectively. RESULTS: IDO expression was found to be enhanced (p = .001) in gastric biopsies from H. pylori-infected (n = 18) compared with uninfected (n = 24) patients. Levels of IDO expression were inversely related to the gastritis score (r = -.684, p = .002) in H. pylori-infected gastric mucosa, but not in uninfected mucosa. In gastric biopsy cultures, IDO inhibition increased the expression of IFN-γ mRNA (p = .014), T-bet (p = .045), and IL-17 (p = .02) while decreasing that of IL-4 (p = .048). CONCLUSIONS: In H. pylori-infected human gastric mucosa, an enhanced expression of IDO is capable of modulating Th1/Th2 and Th17 pathways. This mechanism lowers gastric inflammation, possibly contributing to the persistence of H. pylori. Targeting the IDO pathway may be a new strategy for modulating H. pylori-induced mucosal immune response.


Assuntos
Mucosa Gástrica/patologia , Helicobacter pylori/imunologia , Interações Hospedeiro-Patógeno , Indolamina-Pirrol 2,3,-Dioxigenase/biossíntese , Interleucina-17/metabolismo , Transdução de Sinais , Adolescente , Adulto , Idoso , Biópsia , Western Blotting , Feminino , Perfilação da Expressão Gênica , Humanos , Evasão da Resposta Imune , Interferon gama/biossíntese , Interleucina-4/biossíntese , Masculino , Pessoa de Meia-Idade , Proteínas com Domínio T/biossíntese , Adulto Jovem
5.
Helicobacter ; 19(4): 296-305, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24758553

RESUMO

BACKGROUND: A decreased incidence of Helicobacter pylori infection has been prospected to occur nowadays. AIM: To evaluate the exposure to H. pylori, prevalence and incidence of active infection, and related risk factors in the general population. METHODS: In a small town of Southern Italy (932 inhabitants), 595 (3-97 years) and 157 (12-82 years) subjects among those with no evidence of active H. pylori infection participated at baseline and 10 years later, respectively. A questionnaire was administered. Active H. pylori infection was assessed by (13) C-urea breath test (UBT). Serum VacA and CagA antibodies were determined. RESULTS: Of 518 subjects who were evaluated by both UBT and serology, 310 (59.8%) were UBT positive, 479 (92.4%) VacA positive, and 369 (71.2%) CagA positive. Subjects UBT negative and serology positive were 169 (32%), ranging 1 (14.2%) to 29 (82.8%) from last to first decades of life. Age, female gender, and people per room were independent risk factors for subjects UBT positive compared to those UBT negative and serology positive. Ten years later, subjects who became UBT positive were four of 157 (0.25% per year) while those who became seropositive for VacA and/or CagA were 17 of 26 (6.5% per year). CONCLUSIONS: H. pylori infection is highly dynamic with wide range of spontaneous clearance. It is easily cleared in the first decades of life, more recent years, less crowded homes, and males. It disappears and recurs more often than it was previously thought, implying that the current decline in its prevalence is due to real clearance instead of a fall in infection rate.


Assuntos
Infecções por Helicobacter/epidemiologia , Helicobacter pylori/isolamento & purificação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Testes Respiratórios , Criança , Pré-Escolar , Feminino , Infecções por Helicobacter/diagnóstico , Helicobacter pylori/enzimologia , Helicobacter pylori/imunologia , Humanos , Incidência , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Inquéritos e Questionários , Ureia/análise , Adulto Jovem
6.
World J Gastroenterol ; 18(14): 1622-7, 2012 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-22529691

RESUMO

AIM: To investigate risk factors for low bone mineral density (BMD) in celiac disease (CD) patients, focusing on circulating autoantibodies against osteoprotegerin (OPG). METHODS: Seventy asymptomatic CD adult patients on gluten-free diet (GFD) and harbouring persistent negative CD-related serology were recruited. Conventional risk factors for osteoporosis (e.g., age, sex, menopausal status, history of fractures, smoke, and body mass index) were checked and BMD was assessed by dual energy X ray absorptiometry. Serum calcium and parathyroid hormone (PTH) levels were evaluated. Thirty-eight patients underwent repeat duodenal biopsy. Serum samples from a selected sub-group of 30 patients, who were also typed for human leukocyte antigen (HLA) DQ2 and DQ8 haplotype, were incubated with homodimeric recombinant human OPG and tested by western blotting with an anti-OPG antibody after immunoprecipitation. RESULTS: Despite persistent negative CD-related serology and strict adherence to GFD, 49 out of the 70 (74%) patients displayed low BMD. Among these patients, 13 (24%) showed osteoporosis and 36 (76%) osteopenia. With the exception of age, conventional risk factors for osteoporosis did not differ between patients with normal and low BMD. Circulating serum calcium and PTH levels were normal in all patients. Duodenal mucosa healing was found in 31 (82%) out of 38 patients who underwent repeat duodenal biopsy with 20 (64%) still displaying low BMD. The remaining 7 patients had an incomplete normalization of duodenal mucosa with 6 (84%) showing low BMD. No evidence of circulating antibodies against OPG was found in the serum of 30 celiac patients who were tested for, independent of BMD, duodenal histology, and HLA status. CONCLUSION: If any, the role of circulating autoantibodies against OPG in the pathogenesis of bone derangement in patients with CD is not a major one.


Assuntos
Autoanticorpos/imunologia , Doenças Ósseas Metabólicas/imunologia , Doença Celíaca/imunologia , Osteoporose/imunologia , Osteoprotegerina/imunologia , Adulto , Idoso , Doenças Ósseas Metabólicas/complicações , Cálcio/metabolismo , Doença Celíaca/complicações , Dieta Livre de Glúten , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/complicações
7.
Helicobacter ; 15(5): 449-59, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21083751

RESUMO

BACKGROUND: Selective cyclooxygenase-2 (COX-2) inhibitors and proton pump inhibitors may exert immune-mediated effects in human gastric mucosa. T-cell immune response plays a role in Helicobacter pylori-induced pathogenesis. This study evaluated effects of celecoxib and lansoprazole on T-helper (Th) 1 and Th2 immune response in human gastric mucosa. METHODS: Dyspeptic patients with or without osteoarticular pain were given one of the following 4-week therapies: celecoxib 200 mg, celecoxib 200 mg plus lansoprazole 30 mg, and lansoprazole 30 mg daily. Expression of COX-2, T-bet, and pSTAT6 and production of prostaglandin E2 (PGE2), interferon (IFN)-γ, and interleukin (IL)-4 were determined in gastric biopsies before and after therapy. Histology was evaluated. RESULTS: Cyclooxygenase-2 expression and PGE2 production was higher, and Th1 signaling pathway was predominant in H. pylori-infected vs. uninfected patients. T-bet expression and IFN-γ production increased, while STAT6 activation and IL-4 production decreased following therapy with celecoxib and celecoxib plus lansoprazole, respectively. Th1 and Th2 signaling pathways down-regulated after therapy with lansoprazole, and this was associated with an improvement of gastritis. Effect of therapy was not affected by H. pylori status. CONCLUSION: Celecoxib and lansoprazole modulate Th1/Th2 immune response in human gastric mucosa. The use of these drugs may interfere with long-term course of gastritis.


Assuntos
2-Piridinilmetilsulfinilbenzimidazóis/administração & dosagem , Mucosa Gástrica/imunologia , Fatores Imunológicos/administração & dosagem , Pirazóis/administração & dosagem , Sulfonamidas/administração & dosagem , Células Th1/imunologia , Células Th2/imunologia , 2-Piridinilmetilsulfinilbenzimidazóis/farmacologia , Adulto , Idoso , Celecoxib , Ciclo-Oxigenase 2/biossíntese , Citocinas/metabolismo , Feminino , Helicobacter pylori/imunologia , Helicobacter pylori/patogenicidade , Humanos , Fatores Imunológicos/farmacologia , Lansoprazol , Masculino , Pessoa de Meia-Idade , Inibidores da Bomba de Prótons/administração & dosagem , Inibidores da Bomba de Prótons/farmacologia , Pirazóis/farmacologia , Fator de Transcrição STAT6/biossíntese , Sulfonamidas/farmacologia
8.
J Microbiol Methods ; 75(2): 346-9, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18588923

RESUMO

Gastric biopsies obtained through endoscopy from patients uninfected by Helicobacter pylori were co-cultured with an H. pylori strain. According to tissue and H. pylori viability, interleukin 8 was increased in biopsy homogenate and supernatant after 12-36h culture. This simple method is suitable to investigate early phases of bacteria-host interaction.


Assuntos
Helicobacter pylori/crescimento & desenvolvimento , Interações Hospedeiro-Patógeno , Antro Pilórico/crescimento & desenvolvimento , Antro Pilórico/microbiologia , Adulto , Biópsia , Técnicas de Cocultura , Endoscopia do Sistema Digestório , Células Epiteliais/microbiologia , Feminino , Helicobacter pylori/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Técnicas de Cultura de Órgãos/métodos , Antro Pilórico/citologia
9.
Helicobacter ; 12(3): 193-9, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17492998

RESUMO

BACKGROUND: Evidence suggests that an impaired T-cell response against Helicobacter pylori plays a role in the pathogenesis of H. pylori-related diseases. Cyclooxygenase (COX) 2 has been shown to inhibit the production of T-helper (Th) 1 cytokines. This study aimed to ascertain whether COX-2 downregulates Th1 signaling pathway in human gastric mucosa colonized by H. pylori. METHODS: COX-2 expression and prostaglandin E(2) (PGE(2)) production were determined in total proteins extracted from freshly obtained gastric biopsies of H. pylori-infected and uninfected patients by Western blotting and enzyme-linked immunosorbent assay (ELISA). Phosphorylated (p)STAT4, pSTAT1, T-bet, and pSTAT6 expression and interleukin (IL)-12, interferon (IFN)-gamma, and IL-4 production were also determined by Western blotting and ELISA, respectively, in total protein extracts from gastric biopsy cultures of H. pylori-infected patients treated without and with COX-2 inhibitor NS-398. RESULTS: Enhanced expression of COX-2 and production of PGE(2) was found in H. pylori-infected compared to uninfected patients. COX-2 inhibition significantly increased expression of Th1 transcription factors along with production of IL-12 and IFN-gamma. By contrast, no changes in the expression of STAT6 and production of IL-4 were found. CONCLUSION: This study provides a mechanism by which H. pylori may actually interfere with normal T-cell activation in human gastric mucosa, possibly enhancing its pathogenicity. The use of COX-2 selective inhibitors as immunomodulators in the course of H. pylori infection deserves investigations.


Assuntos
Ciclo-Oxigenase 2/fisiologia , Mucosa Gástrica/imunologia , Infecções por Helicobacter/imunologia , Proteínas de Membrana/fisiologia , Transdução de Sinais/imunologia , Células Th1/imunologia , Ciclo-Oxigenase 2/metabolismo , Regulação para Baixo , Ativação Enzimática , Infecções por Helicobacter/enzimologia , Helicobacter pylori/imunologia , Humanos , Imunidade nas Mucosas/imunologia , Proteínas de Membrana/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA