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1.
Ann Oncol ; 29(12): 2363-2370, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30307529

RESUMO

Background: Gene expression profiling (GEP) studies recognized a prognostic role for tumor microenvironment (TME) in diffuse large B-cell lymphoma (DLBCL), but the routinely adoption of prognostic stromal signatures remains limited. Patients and methods: Here, we applied the computational method CIBERSORT to generate a 1028-gene matrix incorporating signatures of 17 immune and stromal cytotypes. Then, we carried out a deconvolution on publicly available GEP data of 482 untreated DLBCLs to reveal associations between clinical outcomes and proportions of putative tumor-infiltrating cell types. Forty-five genes related to peculiar prognostic cytotypes were selected and their expression digitally quantified by NanoString technology on a validation set of 175 formalin-fixed, paraffin-embedded DLBCLs from two randomized trials. Data from an unsupervised clustering analysis were used to build a model of clustering assignment, whose prognostic value was also assessed on an independent cohort of 40 cases. All tissue samples consisted of pretreatment biopsies of advanced-stage DLBCLs treated by comparable R-CHOP/R-CHOP-like regimens. Results: In silico analysis demonstrated that higher proportion of myofibroblasts (MFs), dendritic cells, and CD4+ T cells correlated with better outcomes and the expression of genes in our panel is associated with a risk of overall and progression-free survival. In a multivariate Cox model, the microenvironment genes retained high prognostic performance independently of the cell-of-origin (COO), and integration of the two prognosticators (COO + TME) improved survival prediction in both validation set and independent cohort. Moreover, the major contribution of MF-related genes to the panel and Gene Set Enrichment Analysis suggested a strong influence of extracellular matrix determinants in DLBCL biology. Conclusions: Our study identified new prognostic categories of DLBCL, providing an easy-to-apply gene panel that powerfully predicts patients' survival. Moreover, owing to its relationship with specific stromal and immune components, the panel may acquire a predictive relevance in clinical trials exploring new drugs with known impact on TME.


Assuntos
Linfoma Difuso de Grandes Células B/mortalidade , Transcriptoma/genética , Microambiente Tumoral/genética , Adulto , Idoso , Algoritmos , Biópsia , Análise por Conglomerados , Estudos de Coortes , Biologia Computacional , Conjuntos de Dados como Assunto , Feminino , Perfilação da Expressão Gênica/métodos , Humanos , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/patologia , Masculino , Pessoa de Meia-Idade , Inclusão em Parafina , Valor Preditivo dos Testes , Prognóstico , Intervalo Livre de Progressão , Ensaios Clínicos Controlados Aleatórios como Assunto , Reprodutibilidade dos Testes , Análise de Sobrevida , Adulto Jovem
3.
G Ital Med Lav Ergon ; 34(3 Suppl): 733-6, 2012.
Artigo em Italiano | MEDLINE | ID: mdl-23405764

RESUMO

The management of indoor air quality in schools needs special attention because it has a strong impact on respiratory health of children with effects also on performance and social development. In Italy a prevention program for indoor environments is provided in the "Guidelines for the prevention of indoor risk factors for allergies and asthma in the school", developed by the Ministry of Health (G.U n. 9 del 13.01.11). In this context, the Ministry of Health has promoted the "Indoor school" project (CCM2010). The main objective of the project is the implementation of these guidelines. In this paper we report the results of the first phase of the project which assessed the knowledge of school principals on issues related to IAQ and building characteristics of the school.


Assuntos
Poluição do Ar em Ambientes Fechados , Proteção da Criança , Monitoramento Ambiental , Doenças Respiratórias/prevenção & controle , Instituições Acadêmicas , Adolescente , Criança , Humanos , Itália , Inquéritos e Questionários
4.
Diabetes Metab Res Rev ; 27(8): 755-60, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22069255

RESUMO

BACKGROUND: Hedgehog pathway plays an important role during pancreas development, when its inactivation is crucial to assure expression of pancreatic marker genes involved in the organ formation and to assure an appropriate organogenesis. Patched1 (Ptch1) is a transmembrane receptor of hedgehog pathway which has a key role in this process. In fact, heterozygous Ptch1 mutant (ptc+/-) mice are affected by an impaired glucose tolerance accompanied by reduced islet function. In the light that the cell distribution of Ptch1 receptor within the endocrine pancreas has not yet been established, we aimed at identifying the pancreatic endocrine cell subset(s) expressing such molecule. METHODS: Double immunostaining for Ptch1 and pancreatic hormones insulin, glucagon and somatostatin on pancreatic paraffin sections of C57BL/6J mice and human non-diabetic multiorgan donors was performed and analysed using confocal microscopy. In addition, diabetes was experimentally induced in mice by intraperitoneal injection of streptozotocin. Quantitative real-time polymerase chain reaction after laser-capture microdissection of different islets from frozen pancreatic murine tissue sections was also performed. RESULTS: Ptch1 receptor was detected only in somatostatin-positive delta cells both in mice and in human pancreas; in mice its expression was not affected by streptozotocin treatment. A significant increase of Ptch1 mRNA expression levels in the islet periphery versus the islet core was observed by quantitative real-time polymerase chain reaction, in accord with immunohistochemical observations. CONCLUSION: Our data show a delta-cell-specific expression of Ptch1 receptor in murine and human pancreas.


Assuntos
Ilhotas Pancreáticas/metabolismo , Receptores de Superfície Celular/biossíntese , Células Secretoras de Somatostatina/metabolismo , Animais , Humanos , Ilhotas Pancreáticas/citologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Receptores Patched , Receptor Patched-1
5.
Ther Adv Chronic Dis ; 12: 20406223211035267, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34422253

RESUMO

BACKGROUND: Tobacco smoking impairs mucociliary clearance (MCC) efficiency as shown by prolonged saccharin test transit time (STTT). Avoiding exposure to tobacco smoke from combustible cigarettes may restore MCC function and former smokers have been shown to exhibit similar STTT as never smokers. The impact on STTT of switching from smoking to combustion-free tobacco products such as e-cigarettes (ECs) and heated tobacco products (HTPs) is not known. METHODS: We report STTT of exclusive EC and HTP users. Test results were compared with those obtained in current, former, and never smokers. RESULTS: STTT were obtained from 39 current, 40 former, 40 never smokers, and from 20 EC and 20 HTP users. Comparison of STTT values showed significant difference among the five study groups (p < 0.00001) with current smokers having a median [interquartile range (IQR)] STTT of 13.15 min, which was significantly longer compared with that of all other study groups. In particular, compared with former (7.26 min) and never smokers (7.24 min), exclusive EC users and exclusive HTP users had similar STTT at 7.00 and 8.00 min, respectively. CONCLUSION: Former smokers who have switched to exclusive regular use of combustion-free nicotine delivery systems (i.e., ECs and HTPs) exhibit similar saccharin transit time as never and former smokers. This suggests that combustion-free nicotine delivery technologies are unlikely to have detrimental effects on MCC function.

6.
J Exp Med ; 184(4): 1561-6, 1996 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-8879230

RESUMO

Castleman's disease is a lymphoproliferative disorder thought to be related to deregulated production of IL-6. We have previously shown that mice lacking the trans-acting factor C/EBP beta, a transcriptional regulator of IL-6 and a mediator of IL-6 intracellular signaling, develop a pathology nearly identical to multicentric Castleman's disease, together with increasingly high levels of circulating IL-6. We describe here how the simultaneous inactivation of both IL-6 and C/EBP beta genes prevents the development of pathological traits of Castleman's disease observed in C/EBP beta-deficient mice. Histological and phenotypic analysis of lymph nodes and spleen of double mutant mice did not show either the lymphoadenopathy and splenomegaly or the abnormal expansion of myeloid, B and plasma cell compartments observed in C/EBP beta-/- mice, while B cell development, although delayed, was normal. Our data demonstrate that IL-6 is essential for the development of multicentric Castleman's disease in C/EBP beta-/- mice.


Assuntos
Hiperplasia do Linfonodo Gigante/genética , Proteínas de Ligação a DNA/genética , Interleucina-6/genética , Proteínas Nucleares/genética , Animais , Linfócitos B/patologia , Proteínas Estimuladoras de Ligação a CCAAT , Hiperplasia do Linfonodo Gigante/patologia , Hiperplasia do Linfonodo Gigante/prevenção & controle , Proteínas de Ligação a DNA/metabolismo , Citometria de Fluxo , Linfonodos/patologia , Camundongos , Camundongos Mutantes , Proteínas Nucleares/metabolismo , Fenótipo , Plasmócitos/patologia , Baço/patologia , Timo/patologia
7.
J Exp Med ; 175(3): 637-46, 1992 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-1740658

RESUMO

The immunosuppressant hormone dexamethasone (Dex) interferes with T cell-specific signals activating the enhancer sequences directing interleukin 2 (IL-2) transcription. We report that the Dex-dependent downregulation of 12-O-tetradecanoyl-phorbol-13-acetate (TPA) and calcium ionophore-induced activity of the IL-2 enhancer are mediated by glucocorticoid receptor (GR) via a process that requires intact NH2- and COOH-terminal and DNA-binding domains. Functional analysis of chloramphenicol acetyltransferase (CAT) vectors containing internal deletions of the -317 to +47 bp IL-2 enhancer showed that the GR-responsive elements mapped to regions containing nuclear factor of activated T cells protein (NFAT) (-279 to -263 bp) and AP-1 (-160 to -150 bp) motifs. The AP-1 motif binds TPA and calcium ionophore-induced nuclear factor(s) containing fos protein. TPA and calcium ionophore-induced transcriptional activation of homo-oligomers of the NFAT element were not inhibited by Dex, while AP-1 motif concatemers were not stimulated by TPA and calcium ionophore. When combined, NFAT and AP-1 motifs significantly synergized in directing CAT transcription. Such a synergism was impaired by specific mutations affecting the trans-acting factor binding to either NFAT or AP-1 motifs. In spite of the lack of hormone regulation of isolated cis elements, TPA/calcium ionophore-mediated activation of CAT vectors containing a combination of the NFAT and the AP-1 motifs became suppressible by Dex. Our results show that the IL-2-AP-1 motif confers GR sensitivity to a flanking region containing a NFAT element and suggest that synergistic cooperativity between the NFAT and AP-1 sites allows GR to mediate the Dex inhibition of IL-2 gene transcription. Therefore, a Dex-modulated second level of IL-2 enhancer regulation, based on a combinatorial modular interplay, appears to be present.


Assuntos
Interleucina-2/genética , Receptores de Glucocorticoides/fisiologia , Linfócitos T/imunologia , Sequência de Bases , Dexametasona/farmacologia , Regulação para Baixo/efeitos dos fármacos , Sinergismo Farmacológico , Elementos Facilitadores Genéticos/fisiologia , Expressão Gênica/efeitos dos fármacos , Tolerância Imunológica/efeitos dos fármacos , Interleucina-1/imunologia , Ativação Linfocitária , Cooperação Linfocítica , Dados de Sequência Molecular , Transcrição Gênica
8.
J Exp Med ; 180(4): 1485-97, 1994 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-7931079

RESUMO

The differentiating agent retinoic acid (RA) has been previously reported to interfere with 12-O-tetradecanoyl-phorbol-13-acetate (TPA)/Ca2+-induced signals for the regulation of the -96 to -66-bp octamer motif found in the enhancer for the interleukin (IL)-2 gene, which encodes a major T lymphocyte growth factor. The IL-2 octamer motif is a composite cis-element which binds Oct-1 and Oct-2 as well as a TPA/Ca2+-inducible nuclear factor, previously termed octamer-associated protein (OAP40). We show here that Oct-2, despite the presence of an active transcriptional activation domain, requires TPA/Ca2+-induced signals to strongly transactivate the IL-2 octamer motif in Jurkat T cells. This Oct-2-dependent transactivation is inhibited by RA. The presence of an intact COOH-terminal domain of Oct-2 contributes to both TPA/Ca2+-induced transactivation and the RA-mediated repression. We also show that both Fos and Jun components of the AP-1 factors participate in the OAP40 complex. Furthermore, transfected c-jun, jun-B, jun-D, c-fos, or Fos-B expression vectors partially substitute for TPA and Ca2+ and cooperate with Oct-2 for the transactivation of the combined OAP/octamer cis-element. Mutations of the genuine octamer-binding site abrogate both the binding of Oct-1 and Oct-2 and the TPA/Ca2+-induced transactivation of the OAP/octamer motif. OAP confers to Oct-2 responsivity to both TPA/Ca2+ and RA, since specific mutations of the AP-1/OAP-binding site significantly reduce the transactivation by Oct-2 in response to TPA and Ca2+ and abolish the inhibition by RA. Furthermore, retinoic acid receptor (RAR) alpha is able to inhibit in vitro the formation of the complex between the nuclear AP-1/OAP and its specific binding site, resulting in the interference with Oct-2-dependent cis-regulatory function of this AP-1 element. Therefore, we propose that the TPA/calcium-activated AP-1/OAP element is the main target of positive or negative regulatory signals influencing the IL-2 octamer motif, through synergism with Oct-2 and antagonism by RAR.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Elementos Facilitadores Genéticos , Interleucina-2/genética , Proteínas Proto-Oncogênicas c-jun/fisiologia , Receptores do Ácido Retinoico/fisiologia , Fatores de Transcrição , Sequência de Bases , Células Cultivadas , DNA/metabolismo , Humanos , Ionomicina/farmacologia , Dados de Sequência Molecular , Fator 2 de Transcrição de Octâmero , Proteínas Proto-Oncogênicas c-fos/fisiologia , Linfócitos T/fisiologia , Acetato de Tetradecanoilforbol/farmacologia , Ativação Transcricional
9.
Br J Dermatol ; 162(3): 518-26, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19903178

RESUMO

BACKGROUND: Hailey-Hailey disease (HHD) is an autosomal dominant disorder characterized by suprabasal cutaneous cell separation (acantholysis) leading to the development of erosive and oozing skin lesions. While a strong relationship exists between mutations in the gene that encodes the Ca(2+)/Mn(2+)-adenosine triphosphatase ATP2C1 and HHD, we still have little understanding of how these mutations affect manifestations of the disease. OBJECTIVES: This study was designed to determine early signalling events that affect epithelial cell growth and differentiation during HHD development. METHODS: Expression of key regulatory signals important for maintaining skin homeostasis were evaluated by Western blot analysis and by reverse transcriptase-polymerase chain reaction in primary keratinocytes obtained from skin biopsies of patients with HHD. Reactive oxygen species accumulation in primary keratinocytes derived from lesional skin of patients with HHD was assessed by dihydrorhodamine 123 (DHR) assay. RESULTS: HHD-derived keratinocytes showed downregulation of both Notch1 and differential regulation of different p63 isoforms. Itch and p63 are co-expressed in the epidermis and in primary keratinocytes where Itch controls the p63 protein steady-state level. We found that the Itch protein was significantly decreased in HHD-derived keratinocytes whereas the expression of its target, c-Jun, remained unaffected. We also found that HHD-derived keratinocytes undergo oxidative stress, which may explain both Notch1 and Itch downregulation. CONCLUSIONS: Our attempt to explore the molecular mechanism underlying HHD indicates a complex puzzle in which multi-hit combinations of altered signal pathways may explain the wide spectrum of defects in HHD.


Assuntos
ATPases Transportadoras de Cálcio/genética , Estresse Oxidativo/genética , Pênfigo Familiar Benigno/genética , Cálcio , ATPases Transportadoras de Cálcio/metabolismo , Análise Mutacional de DNA , Homeostase/genética , Humanos , Linhagem , Pênfigo Familiar Benigno/metabolismo , Fenótipo , Receptores Notch/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos
10.
J Cell Biol ; 130(1): 183-92, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7540616

RESUMO

Neural crest-derived cells populate the thymus, and their coexistence with epithelial cells is required for proper organ development and T cell education function. We show here that epidermal growth factor (EGF), a major epithelial cell growth-enhancing agent, has a morphogenetic action to promote the expression of a neuronal phenotype (e.g., neurofilament expression) in cultured thymic epithelial cells that are characterized by a cytokeratin-positive epithelial cell background. The proliferation of such neurodifferentiated cells is also enhanced by EGF. Furthermore, the growth factor enhances cells that express the genes encoding the preprotachykinin A-generated neuropeptides and bipotential neuropoietic and lymphopoietic cytokines ciliary neurotrophic factor and interleukin-6. These cytokines also enhance the neuronal phenotype of thymic epithelial cells. Therefore, EGF appears to be a composite autocrine/paracrine neuromodulator in thymic stroma. This suggests that EGF may regulate thymus-dependent immune functions by promoting neuronal gene expression in neural crest-derived cells.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Citocinas/fisiologia , Fator de Crescimento Epidérmico/farmacologia , Receptores ErbB/metabolismo , Timo/citologia , Animais , Sequência de Bases , Ciclo Celular , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Fator Neurotrófico Ciliar , Primers do DNA/química , Fator de Crescimento Epidérmico/metabolismo , Células Epiteliais , Imunofluorescência , Expressão Gênica , Técnicas In Vitro , Interleucina-6/fisiologia , Queratinas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Proteínas do Tecido Nervoso/fisiologia , Proteínas de Neurofilamentos/metabolismo , RNA Mensageiro/genética
11.
Eur Rev Med Pharmacol Sci ; 23(10): 4110-4117, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31173280

RESUMO

OBJECTIVE: PANDAS are known as the spectrum of autoimmune pathologies related to a previous or current infection by group A beta-hemolytic streptococcus (SBEGA), dealing with several neuropsychiatric manifestations that mainly affect pediatric age. The main features consist of behavioral disease or movement disease characterized by acute-onset, presenting especially through infant period or adolescence. Specific manifestations, occurring during the progression of the disease, are the presence of otorhinolaryngologic symptoms (ENT) and orofacial movement disorders associated with temporomandibular joint pain. PATIENTS AND METHODS: We enrolled 130 children (5-15 years) with a clinical diagnosis of PANDAS between 2012 and 2018. Participants were assessed using ENT specific parameters, PSG to examine respiratory disorders and conventional audiological evaluation. Descriptive and comparative statistical analyses were performed with a control group of 51 healthy patients. RESULTS: The prevalence of ENT symptoms associated was significantly detected in 88 patients of 130 in Group A (relative frequency (%) 67.6; p=0.041) and in 51 patients of 130 in the control Group B (relative frequency (%) 39.2; p=0.063). In relation to prevalence of SDB, 54 subjects have presented nocturnal respiratory obstructive symptoms from mild to severe (relative frequency (%) 61.3; p=0.033) vs. 20 patients of Group B (relative frequency (%) 39.2; p=0.055). The obstructive severity average type was correlated to the consensual adenotonsillar development (size 3-4), (relative frequency (%) 45.4; p=0.047). The audiological deficits found were mostly of transmissive type with OME correlated and linked to the presence of occasional episodes of AOM. The four PANDAS patients who presented orobuccal dystonia (relative frequency (%) 4.54; p=0.091) achieved an improvement of the algic symptoms through the exercises of self-rehabilitation. CONCLUSIONS: Findings from our study show that respiratory diseases, characterizing a group of patients with pandas, are the direct consequences of the malformed or hypertrophic condition and suggesting in these conditions surgical therapy as an approaching tool.


Assuntos
Doenças Autoimunes/complicações , Doenças Autoimunes/reabilitação , Discinesias/fisiopatologia , Transtornos dos Movimentos/etiologia , Transtorno Obsessivo-Compulsivo/complicações , Transtorno Obsessivo-Compulsivo/reabilitação , Infecções Estreptocócicas/microbiologia , Adolescente , Doenças Autoimunes/diagnóstico , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Humanos , Pneumopatias Obstrutivas/epidemiologia , Pneumopatias Obstrutivas/fisiopatologia , Masculino , Transtornos dos Movimentos/diagnóstico , Transtorno Obsessivo-Compulsivo/epidemiologia , Otorrinolaringopatias/epidemiologia , Otorrinolaringopatias/fisiopatologia , Dor/etiologia , Prevalência , Índice de Gravidade de Doença , Infecções Estreptocócicas/complicações , Infecções Estreptocócicas/reabilitação , Streptococcus pyogenes/isolamento & purificação , Articulação Temporomandibular/patologia
12.
J Clin Endocrinol Metab ; 93(10): 4080-7, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18664540

RESUMO

CONTEXT: Notch genes encode receptors for a signaling pathway that regulates cell growth and differentiation in various contexts, but the role of Notch signaling in thyroid follicular cells has never been fully published. OBJECTIVE: The objective of the study was to characterize the expression of Notch pathway components in thyroid follicular cells and Notch signaling activities in normal and transformed thyrocytes. DESIGN/SETTING AND PATIENTS: Expression of Notch pathway components and key markers of thyrocyte differentiation was analyzed in murine and human thyroid tissues (normal and tumoral) by quantitative RT-PCR and immunohistochemistry. The effects of Notch overexpression in human thyroid cancer cells and FTRL-5 cells were explored with analysis of gene expression, proliferation assays, and experiments involving transfection of a luciferase reporter construct containing human NIS promoter regions. RESULTS: Notch receptors are expressed during the development of murine thyrocytes, and their expression levels parallel those of thyroid differentiation markers. Notch signaling characterized also normal adult thyrocytes and is regulated by TSH. Notch pathway components are variably expressed in human normal thyroid tissue and thyroid tumors, but expression levels are clearly reduced in undifferentiated tumors. Overexpression of Notch-1 in thyroid cancer cells restores differentiation, reduces cell growth rates, and stimulates NIS expression via a direct action on the NIS promoter. CONCLUSION: Notch signaling is involved in the determination of thyroid cell fate and is a direct regulator of thyroid-specific gene expression. Its deregulation may contribute to the loss of differentiation associated with thyroid tumorigenesis.


Assuntos
Biomarcadores/metabolismo , Carcinoma Papilar/genética , Diferenciação Celular/genética , Receptores Notch/fisiologia , Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/genética , Adenocarcinoma Folicular/genética , Adenocarcinoma Folicular/metabolismo , Animais , Carcinoma Papilar/metabolismo , Desdiferenciação Celular/genética , Células Cultivadas , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Especificidade de Órgãos/genética , Receptores Notch/genética , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Simportadores/genética , Simportadores/metabolismo , Glândula Tireoide/citologia , Glândula Tireoide/embriologia , Neoplasias da Glândula Tireoide/metabolismo
13.
Oncogene ; 25(55): 7267-73, 2006 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-16878160

RESUMO

Medulloblastoma (MB) results from aberrant development of cerebellar neurons in which altered hedgehog (Hh) signalling plays a major role. We investigated the possible influence of Hh signalling on ErbB-receptor expression in MB, in particular that of the ErbB-4 CYT-1 and CYT-2 isoforms generated by alternative splicing of the cytoplasmic domain. ErbB-4 expression was downregulated in Hh-induced MBs from Patched-1(+/-) mice. Hh signalling (reflected by enhanced expression of the Gli1 transcription factor) inhibited ErbB-4 expression in mouse cerebellar granule progenitors and human MB cells. Analysis of 26 human primary MBs revealed a subset of 11 tumors characterized by low Gli1 levels, upregulated ErbB-4 expression and increased CYT-1:CYT-2 ratios. Interestingly, CYT-1 and Gli1 levels were inversely correlated. ErbB-4 CYT-1 and CYT-2 had different phenotypic effects in cultured MB cells: in response to neuregulin treatment, CYT-2 overexpression inhibited proliferation whereas CYT-1, which includes a phosphatidylinositol 3-kinase (PI3K)-binding site that is missing in CYT-2, enhanced resistance to starvation- and etoposide-induced apoptosis by activating PI3K/Akt signalling. CYT-1:CYT-2 ratios displayed correlation with tumor histotype and ErbB-2 levels, which are established prognostic indices for MB. These findings demonstrate that low-level Hh signalling in human MB is associated with the selective maintenance of high ErbB-4 CYT-1 expression, an alteration that exerts tumor-promoting effects.


Assuntos
Processamento Alternativo , Citoplasma/metabolismo , Receptores ErbB/metabolismo , Proteínas Hedgehog/metabolismo , Meduloblastoma/classificação , Transdução de Sinais , Animais , Sequência de Bases , Primers do DNA , Humanos , Meduloblastoma/metabolismo , Meduloblastoma/patologia , Camundongos , Prognóstico , Receptor ErbB-4 , Reação em Cadeia da Polimerase Via Transcriptase Reversa
14.
J Clin Endocrinol Metab ; 92(7): 2840-3, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17488796

RESUMO

CONTEXT: BRAF mutations are common in papillary thyroid carcinomas (PTCs). By affecting the expression of genes critically related to the development and differentiation of thyroid cancer, they may influence the prognosis of these tumors. OBJECTIVE: Our objective was to characterize the expression of thyroid-specific genes associated with BRAF mutation in PTCs. DESIGN/SETTING AND PATIENTS: We examined the expression of key markers of thyrocyte differentiation in 56 PTCs with BRAF mutations (BRAF-mut) and 37 with wild-type BRAF (BRAF-wt). Eight samples of normal thyroid tissue were analyzed as controls. Quantitative PCR was used to measure mRNA levels for the sodium/iodide symporter (NIS), apical iodide transporter (AIT-B), thyroglobulin (Tg), thyroperoxidase (TPO), TSH receptor (TSH-R), the transcription factor PAX8, and glucose transporter type 1 (Glut1). NIS protein expression and localization was also analyzed by immunohistochemistry. RESULTS: mRNA levels for all thyroid-specific genes were reduced in all PTCs vs. normal thyroid tissues. NIS, AIT-B, Tg, and TPO expression was significantly lower in BRAF-mut tumors than in the BRAF-wt group. Glut-1 transcript levels were increased in all PTCs, and additional increases were noted in BRAF-mut tumors. In both tumor subsets, the NIS protein that was expressed was abnormally retained in the cytoplasm. CONCLUSION: BRAF V600E mutation in PTCs is associated with reduced expression of key genes involved in iodine metabolism. This effect may alter the effectiveness of diagnostic and/or therapeutic use of radioiodine in BRAF-mut PTCs.


Assuntos
Carcinoma Papilar/genética , Regulação Neoplásica da Expressão Gênica , Iodo/metabolismo , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias da Glândula Tireoide/genética , Adulto , Idoso , Carcinoma Papilar/metabolismo , Diferenciação Celular , Feminino , Marcadores Genéticos , Humanos , Masculino , Pessoa de Meia-Idade , Mutação Puntual , RNA Mensageiro/metabolismo , Neoplasias da Glândula Tireoide/metabolismo
15.
J Endocrinol ; 194(3): 475-84, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17761887

RESUMO

Basic helix-loop-helix (bHLH) transcription factors are involved in neuroendocrine cell growth and differentiation. Though NeuroD1 is viewed as corticotroph specific, its overexpression in non-corticotroph pituitary adenomas (PAs) may reflect the activation of molecular pathways involving other bHLH factors, like neurogenins. To search for neurogenin-NeuroD1 molecular pathways in the human normal and tumoural pituitary. Fifty-one PAs--22 clinically non-secreting (CNS) and 29 secreting respectively--and normal human pituitaries (NP) were studied for NeuroD1 and neurogenins (Ngn1, Ngn2 and Ngn3) gene expression by RT-PCR and quantitative real-time RT-PCR (qRT-PCR). Immunohistochemistry for Ngn2/3 was performed in some cases. NeuroD1, Ngn2, Ngn3 and Ngn1 were observed in up to 84.3, 76.5, 30.4 and 9.1% of PA respectively, only NeuroD1 and Ngn2 being frequently overexpressed when compared with NP. Whereas NeuroD1 expression was higher in corticotroph and CNS adenomas (P=0.0001 versus Pit-1-dependent PA), Ngn2 expression was higher in secreting PA, especially in Pit-1-dependent PA (P=0.007 and P=0.0006 versus CNS respectively). Pit-1-dependent PA which received pre-operative pharmacological treatment expressed higher Ngn2 levels than untreated cases (P=0.025). Nuclear Ngn2 was observed in NP and in most PA, especially ACTH- and GH-secreting adenomas. Nuclear Ngn3 was observed in a minority of secreting PA. Ngn2 is normally expressed in the anterior pituitary and frequently expressed in PA, but does not account for NeuroD1 overexpression where present. Owing to their low and inconstant expression, the biological significance of Ngn1/3 in the adult pituitary is uncertain.


Assuntos
Adenoma/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Hipofisárias/metabolismo , Adolescente , Hormônio Adrenocorticotrópico/metabolismo , Adulto , Idoso , Fatores de Transcrição Hélice-Alça-Hélice Básicos/análise , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Criança , Feminino , Expressão Gênica , Hormônio do Crescimento/metabolismo , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/análise , Proteínas do Tecido Nervoso/genética , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estatísticas não Paramétricas
16.
Mol Cell Biol ; 11(9): 4771-8, 1991 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1652063

RESUMO

Retinoic acid (RA) is known to influence the proliferation and differentiation of a wide variety of transformed and developing cells. We found that RA and the specific RA receptor (RAR) ligand Ch55 inhibited the phorbol ester and calcium ionophore-induced expression of the T-cell growth factor interleukin-2 (IL-2) gene. Expression of transiently transfected chloramphenicol acetyltransferase vectors containing the 5'-flanking region of the IL-2 gene was also inhibited by RA. RA-induced down-regulation of the IL-2 enhancer is mediated by RAR, since overexpression of transfected RARs increased RA sensitivity of the IL-2 promoter. Functional analysis of chloramphenicol acetyltransferase vectors containing either internal deletion mutants of the region from -317 to +47 bp of the IL-2 enhancer or multimerized cis-regulatory elements showed that the RA-responsive element in the IL-2 promoter mapped to sequences containing an octamer motif. RAR also inhibited the transcriptional activity of the octamer motif of the immunoglobulin heavy chain enhancer. In spite of the transcriptional inhibition of the IL-2 octamer motif, RA did not decrease the in vitro DNA-binding capability of octamer-1 protein. These results identify a regulatory pathway within the IL-2 promoter which involves the octamer motif and RAR.


Assuntos
Interleucina-2/genética , Regiões Promotoras Genéticas , Tretinoína/metabolismo , Sequência de Bases , Proteínas de Transporte/metabolismo , Linhagem Celular , DNA , Regulação para Baixo , Regulação da Expressão Gênica , Humanos , Dados de Sequência Molecular , RNA Mensageiro/metabolismo , Receptores do Ácido Retinoico , Transcrição Gênica/efeitos dos fármacos
17.
Oncogene ; 36(33): 4682-4691, 2017 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-28394338

RESUMO

High-risk and MYCN-amplified neuroblastomas are among the most aggressive pediatric tumors. Despite intense multimodality therapies, about 50% of these patients succumb to their disease, making the search for effective therapies an absolute priority. Due to the important functions of poly (ADP-ribose) polymerases, PARP inhibitors have entered the clinical settings for cancer treatment and are being exploited in a variety of preclinical studies and clinical trials. PARP inhibitors based combination schemes have also been tested in neuroblastoma preclinical models with encouraging results. However, the expression of PARP enzymes in human neuroblastoma and the biological consequences of their inhibition remained largely unexplored. Here, we show that high PARP1 and PARP2 expression is significantly associated with high-risk neuroblastoma cases and poor survival, highlighting its previously unrecognized prognostic value for human neuroblastoma. In vitro, PARP1 and 2 are abundant in MYCN amplified and MYCN-overexpressing cells. In this context, PARP inhibitors with high 'PARP trapping' potency, such as olaparib or talazoparib, yield DNA damage and cell death preceded by intense signs of replication stress. Notwithstanding the activation of a CHK1-CDC25A replication stress response, PARP-inhibited MYCN amplified and overexpressing cells fail to sustain a prolonged checkpoint and progress through mitosis in the presence of damaged DNA, eventually undergoing mitotic catastrophe. CHK1-targeted inhibition of the replication stress checkpoint exacerbated this phenotype. These data highlight a novel route for cell death induction by PARP inhibitors and support their introduction, together with CHK1 inhibitors, in therapeutic approaches for neuroblastomas with high MYC(N) activity.


Assuntos
Replicação do DNA/efeitos dos fármacos , Mitose/efeitos dos fármacos , Proteína Proto-Oncogênica N-Myc/metabolismo , Neuroblastoma/tratamento farmacológico , Poli(ADP-Ribose) Polimerase-1/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Poli(ADP-Ribose) Polimerases/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Quinase 1 do Ponto de Checagem/metabolismo , Criança , Humanos , Estimativa de Kaplan-Meier , Proteína Proto-Oncogênica N-Myc/genética , Poli(ADP-Ribose) Polimerase-1/genética , Inibidores de Poli(ADP-Ribose) Polimerases/administração & dosagem , Poli(ADP-Ribose) Polimerases/genética
18.
Ann Oncol ; 17 Suppl 7: vii34-40, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16760289

RESUMO

BACKGROUND: Breast cancer is an extremely complex disease, characterized by a progressive multistep process caused by interactions of both genetic and non-genetic factors. A combination of BRCA1 and BRCA2 gene mutations appears responsible for about 20%-30% of the cases with breast cancer familial history. The prevalence of BRCA1/2 pathogenic mutations largely varies within different populations; in particular, the rate of mutations in Italian breast and/or ovarian cancer families is rather controversial and ranges from 8% to 37%. PATIENTS AND METHODS: Of the 152 breast/ovarian cancer families counseled in our centre, 99 were selected for BRCA1/2 mutation screening according to our minimal criteria. The entire coding sequences and each intron/exon boundary of BRCA1/2 genes were screened by direct sequencing (PTT limited to BRCA1 exon 11). For each proband, the a priori probability of carrying a pathogenic BRCA1/2 germline mutation was calculated by means of different mutation prediction models (BRCApro, IC and Myriad Table) in order to evaluate their performances. RESULTS: Our analysis resulted in the identification of 25 and 52 variants in the BRCA1 and BRCA2 genes, respectively. Seventeen of them represent novel variants, including four deleterious truncating mutations in the BRCA2 gene (472insA, E33X, C1630X and IVS6+1G>C). Twenty-seven of the 99 probands harbored BRCA1 (n = 15) and BRCA2 (n = 12) pathogenic germline mutations, indicating an overall detection rate of 27.3% and increasing by more than 15% the spectrum of mutations in the Italian population. Furthermore, we found the lowest detection rate (19.4%) in pure hereditary breast cancer family subset. All of the prediction models showed praises and faults, with the IC software being extremely sensitive but poorly specific, compared to BRCApro. In particular all models accumulated most false-negative prediction in the HBC subset. Interestingly preliminary results of a study addressing the presence of genomic rearrangements in HBC probands with BRCApro or IC prediction scores >/=95%, provided evidence for additional mutations undetectable with our conventional screening for point mutations. CONCLUSIONS: Altogether our results suggest that HBC families, the largest pool in our series, represent an heterogeneous group where the apparently faulty performances of the prediction models might be at least partially explained by the presence of additional kinds of BRCA1/2 alteration (such as genomic rearrangements) or by mutations on different breast cancer related genes.


Assuntos
Neoplasias da Mama/genética , Genes BRCA1 , Genes BRCA2 , Mutação em Linhagem Germinativa , Neoplasias Ovarianas/genética , Adulto , Feminino , Deleção de Genes , Testes Genéticos , Humanos , Itália , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Polimorfismo Genético , Prevalência
19.
Eur J Cancer ; 42(15): 2631-8, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16928445

RESUMO

We characterised the expression of the plasminogen activators (uPA and tPA), the uPA receptor (uPAR) and the PAs inhibitors (PAI-1 and PAI-2) in human thyroid cell lines derived from normal thyroid, follicular adenoma, follicular, papillary and anaplastic carcinomas. Urokinase PA activity was detected in the supernatant of normal thyrocytes and augmented in those of all tumour cells. Quantitative RT-PCR analysis showed that uPA, uPAR and PAI-1 mRNAs increased in all carcinoma cells. Similar results were found in 13 papillary thyroid carcinoma (PTC) tissues which were mirrored in Western blot experiments. A correlation was found between tumour size and uPA mRNA increase, and higher levels of uPA and uPAR mRNAs were found in metastatic PTC. In conclusion, thyroid carcinoma cell lines and PTC overexpress uPA, uPAR and PAI-1 and the correlation of uPA and its cognate receptor with tumour size and metastasis may suggest their potential prognostic relevance in thyroid cancer.


Assuntos
Carcinoma Papilar/metabolismo , Proteínas de Neoplasias/metabolismo , Ativadores de Plasminogênio/metabolismo , Neoplasias da Glândula Tireoide/metabolismo , Western Blotting , Linhagem Celular Tumoral , Humanos , Metástase Neoplásica , Prognóstico , RNA Mensageiro/metabolismo , RNA Neoplásico/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ativador de Plasminogênio Tipo Uroquinase/metabolismo
20.
Int J Immunopathol Pharmacol ; 19(4): 761-73, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17166398

RESUMO

Tumors escape from immune surveillance by, among other mechanisms, the down- regulation of endothelial adhesion molecules, such as ICAM-1, and by unresponsiveness to inflammatory signals, a process mediated by angiogenic factors that is called endothelial cell anergy. Here we present the cell biological regulation of these processes. The angiogenic basic fibroblast growth factor (bFGF/FGF-2) was found to inhibit tumor necrosis factor-alpha (TNF-alpha)- induced elevation of ICAM-1, at transcriptional level. Furthermore, we found that bFGF inhibits the TNF-mediated activation of NF-kappaB by blocking phosphorylation and degradation of IkappaBalpha. We also found that bFGF induces hyperphosphorylation of p38 MAPK on endothelial cells, whereas inhibition of such kinase abrogates the effect of bFGF on the TNF-mediated activation of NF-kappaB. Thus, we suggest that bFGF acts as an inhibitor of leukocyte adhesion in tumor vessels by decreasing the ICAM-1 expression through the sustained activation of p38-MAPK and via inhibition of NF-kappaB.


Assuntos
Anergia Clonal/fisiologia , Endotélio Vascular/imunologia , Fator 2 de Crescimento de Fibroblastos/fisiologia , NF-kappa B/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Linhagem Celular , Regulação para Baixo/fisiologia , Endotélio Vascular/enzimologia , Endotélio Vascular/metabolismo , Ativação Enzimática , Humanos , Molécula 1 de Adesão Intercelular/genética , Fosforilação , RNA Mensageiro/genética , Fator de Necrose Tumoral alfa/metabolismo
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