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1.
Arch Toxicol ; 92(5): 1785-1795, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29523930

RESUMO

Occupational and environmental asbestos exposure is the main determinant of malignant pleural mesothelioma (MPM), however, the mechanisms by which its fibres contribute to cell toxicity and transformation are not completely clear. Aberrant DNA methylation is a common event in cancer but epigenetic modifications involved specifically in MPM carcinogenesis need to be better clarified. To investigate asbestos-induced DNA methylation and gene expression changes, we treated Met5A mesothelial cells with different concentrations of crocidolite and chrysotile asbestos (0.5 ÷ 5.0 µg/cm2, 72 h incubation). Overall, we observed 243 and 302 differentially methylated CpGs (≥ 10%) between the asbestos dose at 5 µg/cm2 and untreated control, in chrysotile and crocidolite treatment, respectively. To examine the dose-response effect, Spearman's correlation test was performed and significant CpGs located in genes involved in migration/cell adhesion processes were identified in both treatments. Moreover, we found that both crocidolite and chrysotile exposure induced a significant up-regulation of CA9 and SRGN (log2 fold change > 1.5), previously reported as associated with a more aggressive MPM phenotype. However, we found no correlation between methylation and gene expression changes, except for a moderate significant inverse correlation at the promoter region of DKK1 (Spearman rho = - 1, P value = 0.02) after chrysotile exposure. These results describe for the first time the relationship between DNA methylation modifications and asbestos exposure. Our findings provide a basis to further explore and validate asbestos-induced DNA methylation changes, that could influence MPM carcinogenesis and possibly identifying new chemopreventive target.


Assuntos
Amianto/toxicidade , Metilação de DNA/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos , Antígenos de Neoplasias/genética , Amianto/química , Asbesto Crocidolita/administração & dosagem , Asbesto Crocidolita/toxicidade , Asbestos Serpentinas/administração & dosagem , Asbestos Serpentinas/toxicidade , Anidrase Carbônica IX/genética , Linhagem Celular , Relação Dose-Resposta a Droga , Células Epiteliais/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/genética , Mesotelioma/induzido quimicamente , Mesotelioma/genética , Mesotelioma Maligno , Reação em Cadeia da Polimerase em Tempo Real
2.
Cancer Lett ; 378(2): 120-30, 2016 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-27181379

RESUMO

BAP1 germline mutations predispose to a cancer predisposition syndrome that includes mesothelioma, cutaneous melanoma, uveal melanoma and other cancers. This co-occurrence suggests that these tumors share a common carcinogenic pathway. To evaluate this hypothesis, we studied 40 Italian families with mesothelioma and/or melanoma. The probands were sequenced for BAP1 and for the most common melanoma predisposition genes (i.e. CDKN2A, CDK4, TERT, MITF and POT1) to investigate if these genes may also confer susceptibility to mesothelioma. In two out of six families with both mesothelioma and melanoma we identified either a germline nonsense mutation (c.1153C > T, p.Arg385*) in BAP1 or a recurrent pathogenic germline mutation (c.301G > T, p.Gly101Trp) in CDKN2A. Our study suggests that CDKN2A, in addition to BAP1, could be involved in the melanoma and mesothelioma susceptibility, leading to the rare familial cancer syndromes. It also suggests that these tumors share key steps that drive carcinogenesis and that other genes may be involved in inherited predisposition to malignant mesothelioma and melanoma.


Assuntos
Biomarcadores Tumorais/genética , Códon sem Sentido , Inibidor de Quinase Dependente de Ciclina p18/genética , Mutação em Linhagem Germinativa , Melanoma/genética , Mesotelioma/genética , Neoplasias Cutâneas/genética , Proteínas Supressoras de Tumor/genética , Ubiquitina Tiolesterase/genética , Adolescente , Adulto , Idoso , Biomarcadores Tumorais/análise , Inibidor p16 de Quinase Dependente de Ciclina , Inibidor de Quinase Dependente de Ciclina p18/análise , Análise Mutacional de DNA , Bases de Dados Factuais , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Hereditariedade , Humanos , Imuno-Histoquímica , Itália , Masculino , Melanoma/química , Melanoma/patologia , Mesotelioma/química , Mesotelioma/patologia , Pessoa de Meia-Idade , Linhagem , Fenótipo , Fatores de Risco , Neoplasias Cutâneas/química , Neoplasias Cutâneas/patologia , Proteínas Supressoras de Tumor/análise , Ubiquitina Tiolesterase/análise , Adulto Jovem
3.
Med Lav ; 106(5): 325-32, 2015 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-26384258

RESUMO

The III Italian Consensus Conference on Pleural Mesothelioma (MM) convened on January 29th 2015. This report presents the conclusions of the 'Epidemiology, Public Health and Occupational Medicine' section. MM incidence in 2011 in Italy was 3.64 per 100,000 person/years in men and 1.32 in women. Incidence trends are starting to level off. Ten percent of cases are due to non-occupational exposure. Incidence among women is very high in Italy, because of both non-occupational and occupational exposure. The removal of asbestos in place is proceeding slowly, with remaining exposure. Recent literature confirms the causal role of chrysotile. Fibrous fluoro-edenite was classified as carcinogenic by IARC (Group 1) on the basis of MM data. A specific type (MWCNT-7) of Carbon Nanotubes was classified 2B. For pleural MM, after about 45 years since first exposure, the incidence trend slowed down; with more studies needed. Cumulative exposure is a proxy of the relevant exposure, but does not allow to distinguish if duration or intensity may possibly play a prominent role, neither to evaluate the temporal sequence of exposures. Studies showed that duration and intensity are independent determinants of MM. Blood related MM are less than 2.5%. The role of BAP1 germline mutations is limited to the BAP1 cancer syndrome, but negligible for sporadic cases. Correct MM diagnosis is baseline; guidelines agree on the importance of the tumor gross appearance and of the hematoxylin-eosin-based histology. Immunohistochemical markers contribute to diagnostic confirmation: the selection depends on morphology, location, and differential diagnosis. The WG suggested that 1) General Cancer Registries and ReNaM Regional Operational Centres (COR) interact and systematically compare MM cases; 2) ReNaM should report results presenting the diagnostic certainty codes and the diagnostic basis, separately; 3) General Cancer Registries and COR should interact with pathologists to assure the up-to-date methodology; 4) Necroscopy should be practiced for validation. Expert referral centres could contribute to the definition of uncertain cases. Health surveillance should aim to all asbestos effects. No diagnostic test is recommended for MM screening. Health surveillance should provide information on risks, medical perspective, and smoking cessation. The economic burden associated to MM was estimated in 250,000 Euro per case.


Assuntos
Neoplasias Pulmonares , Mesotelioma , Doenças Profissionais , Neoplasias Pleurais , Amianto/efeitos adversos , Humanos , Itália , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/etiologia , Mesotelioma/epidemiologia , Mesotelioma/etiologia , Mesotelioma Maligno , Doenças Profissionais/epidemiologia , Doenças Profissionais/etiologia , Medicina do Trabalho , Neoplasias Pleurais/epidemiologia , Neoplasias Pleurais/etiologia , Saúde Pública
4.
Genes Immun ; 16(2): 151-61, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25569260

RESUMO

Lymphocyte apoptosis is mainly induced by either death receptor-dependent activation of caspase-8 or mitochondria-dependent activation of caspase-9. Mutations in caspase-8 lead to autoimmunity/lymphoproliferation and immunodeficiency. This work describes a heterozygous H237P mutation in caspase-9 that can lead to similar disorders. H237P mutation was detected in two patients: Pt1 with autoimmunity/lymphoproliferation, severe hypogammaglobulinemia and Pt2 with mild hypogammaglobulinemia and Burkitt lymphoma. Their lymphocytes displayed defective caspase-9 activity and decreased apoptotic and activation responses. Transfection experiments showed that mutant caspase-9 display defective enzyme and proapoptotic activities and a dominant-negative effect on wild-type caspase-9. Ex vivo analysis of the patients' lymphocytes and in vitro transfection experiments showed that the expression of mutant caspase-9 correlated with a downregulation of BAFFR (B-cell-activating factor belonging to the TNF family (BAFF) receptor) in B cells and ICOS (inducible T-cell costimulator) in T cells. Both patients carried a second inherited heterozygous mutation missing in the relatives carrying H237P: Pt1 in the transmembrane activator and CAML interactor (TACI) gene (S144X) and Pt2 in the perforin (PRF1) gene (N252S). Both mutations have been previously associated with immunodeficiencies in homozygosis or compound heterozygosis. Taken together, these data suggest that caspase-9 mutations may predispose to immunodeficiency by cooperating with other genetic factors, possibly by downregulating the expression of BAFFR and ICOS.


Assuntos
Receptor do Fator Ativador de Células B/biossíntese , Caspase 9/genética , Síndromes de Imunodeficiência/genética , Proteína Coestimuladora de Linfócitos T Induzíveis/biossíntese , Transtornos Linfoproliferativos/genética , Mutação , Adolescente , Adulto , Apoptose/genética , Apoptose/imunologia , Receptor do Fator Ativador de Células B/genética , Receptor do Fator Ativador de Células B/imunologia , Caspase 9/imunologia , Regulação para Baixo , Células HEK293 , Humanos , Síndromes de Imunodeficiência/imunologia , Síndromes de Imunodeficiência/metabolismo , Proteína Coestimuladora de Linfócitos T Induzíveis/genética , Proteína Coestimuladora de Linfócitos T Induzíveis/imunologia , Transtornos Linfoproliferativos/imunologia , Transtornos Linfoproliferativos/metabolismo , Masculino , Linhagem
5.
Mutat Res ; 708(1-2): 11-20, 2011 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-21277872

RESUMO

Malignant pleural mesothelioma (MPM) is a rare aggressive tumor associated with asbestos exposure. The possible role of genetic factors has also been suggested and MPM has been associated with single nucleotide polymorphisms (SNPs) of xenobiotic and oxidative metabolism enzymes. We have identified an association of the DNA repair gene XRCC1 with MPM in the population of Casale Monferrato, a town exposed to high asbestos pollution. To extend this observation we examined 35 SNPs in 15 genes that could be involved in MPM carcinogenicity in 220 MPM patients and 296 controls from two case-control studies conducted in Casale (151 patients, 252 controls) and Turin (69 patients, 44 controls), respectively. Unconditional multivariate logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (95% CIs). Two DNA repair genes were associated with MPM, i.e. XRCC1 and ERCC1. Considering asbestos-exposed only, the risk increased with the increasing number of XRCC1-399Q alleles (Casale: OR=1.44, 95%CI 1.02-2.03; Casale+Turin: OR=1.34, 95%CI 0.98-1.84) or XRCC1 -77T alleles (Casale+Turin: OR=1.33, 95%CI 0.97-1.81). The XRCC1-TGGGGGAACAGA haplotype was significantly associated with MPM (Casale: OR=1.76, 95%CI 1.04-2.96). Patients heterozygotes for ERCC1 N118N showed an increased OR in all subjects (OR=1.66, 95%CI 1.06-2.60) and in asbestos-exposed only (OR=1.59, 95%CI 1.01-2.50). When the dominant model was considered (i.e. ERCC1 heterozygotes CT plus homozygotes CC versus homozygotes TT) the risk was statistically significant both in all subjects (OR=1.61, 95%CI 1.06-2.47) and in asbestos-exposed only (OR=1.56, 95%CI 1.02-2.40). The combination of ERCC1 N118N and XRCC1 R399Q was statistically significant (Casale: OR=2.02, 95%CI 1.01-4.05; Casale+Turin: OR=2.39, 95%CI 1.29-4.43). The association of MPM with DNA repair genes support the hypothesis that an increased susceptibility to DNA damage may favour asbestos carcinogenicity.


Assuntos
Proteínas de Ligação a DNA/genética , Endonucleases/genética , Mesotelioma/genética , Polimorfismo de Nucleotídeo Único , Amianto/toxicidade , Sequência de Bases , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Proteína 1 Complementadora Cruzada de Reparo de Raio-X
6.
Oncogene ; 29(40): 5490-9, 2010 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-20639905

RESUMO

PIM1 is a constitutively active serine/threonine kinase regulated by cytokines, growth factors and hormones. It has been implicated in the control of cell cycle progression and apoptosis and its overexpression has been associated with various kinds of lymphoid and hematopoietic malignancies. The activity of PIM1 is dependent on the phosphorylation of several targets involved in transcription, cell cycle and apoptosis. We have recently observed that PIM1 interacts with ribosomal protein (RP)S19 and cosediments with ribosomes. Defects in ribosome synthesis (ribosomal stress) have been shown to activate a p53-dependent growth arrest response. To investigate if PIM1 could have a role in the response to ribosomal stress, we induced ribosome synthesis alterations in TF-1 and K562 erythroid cell lines. We found that RP deficiency, induced by RNA interference or treatment with inhibitor of nucleolar functions, causes a drastic destabilization of PIM1. The lower level of PIM1 induces an increase in the cell cycle inhibitor p27(Kip1) and blocks cell proliferation even in the absence of p53. Notably, restoring PIM1 level by transfection causes a recovery of cell growth. Our data indicate that PIM1 may act as a sensor for ribosomal stress independently of or in concert with the known p53-dependent mechanisms.


Assuntos
Ciclo Celular/fisiologia , Proteínas Proto-Oncogênicas c-pim-1/metabolismo , Proteínas Ribossômicas/metabolismo , Ribossomos/metabolismo , Estresse Fisiológico , Western Blotting , Linhagem Celular Tumoral , Proliferação de Células , Separação Celular , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Citometria de Fluxo , Expressão Gênica , Regulação da Expressão Gênica , Humanos , Proteínas Proto-Oncogênicas c-pim-1/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/fisiologia , Estresse Fisiológico/fisiologia , Proteína Supressora de Tumor p53/metabolismo
8.
J Clin Pathol ; 59(4): 440-2, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16567474

RESUMO

BACKGROUND: Familial tumoral calcinosis (FTC) is a rare autosomal recessive disease characterised by the development of multiple calcified masses in periarticular soft tissues; GALNT3 gene mutations have recently been described in an African American and in a Druse Arab family with FTC. OBJECTIVE: To report the clinical and histological features caused by a new GALNT3 mutation in a white family. RESULTS: Homozygosity for the nonsense mutation Lys463X was found in both affected siblings, who displayed a classic phenotype, the male also having testicular microlithiasis. He is the first subject described with testicular microlithiasis in FTC. CONCLUSIONS: The high testicular expression of GALNT3 suggests that the gene alteration could act locally by causing deposition of calcium, and the testis may be an underestimated site of calcification in FTC. Autoimmune diseases are present in several members of the family. Although immune disorders have been described in FTC, autoimmunity does not segregate with the GALNT3 mutation in this family.


Assuntos
Calcinose/genética , Códon sem Sentido , Litíase/genética , N-Acetilgalactosaminiltransferases/genética , Proteínas de Neoplasias/genética , Doenças Testiculares/genética , Doenças Autoimunes/genética , Doenças Autoimunes/metabolismo , Calcinose/metabolismo , Calcinose/patologia , Criança , Humanos , Itália , Litíase/metabolismo , Litíase/patologia , Masculino , Linhagem , Doenças Testiculares/etnologia , Doenças Testiculares/metabolismo , População Branca , Polipeptídeo N-Acetilgalactosaminiltransferase
9.
Mutat Res ; 599(1-2): 124-34, 2006 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-16564556

RESUMO

Differences in response to carcinogenic agents are due to the allelic variants of the genes that control it. Key genes are those involved in the repair of the DNA damage caused by such agents. This paper describes the results of a case-control epidemiological study designed to determine the genotypes of four of these genes in persons exposed to a single genotoxic factor, i.e. asbestos, who had or had not developed malignant mesothelioma (MM). Our working hypothesis was that an imperfect DNA repair, as revealed by subtle polymorphic variants, could reduce protection against the chronic DNA insult provoked by asbestos and eventually result in mutagenesis and cancer. Seven variants (i.e. XRCC1-R399Q-NCBI SNP, XRCC1-R194W, XRCC3-T241M, XRCC3-IVS6-14, XPD-K751Q, XPD-D312N, OGG1-S326C) were investigated in 81 patients and 110 age and sex-matched controls, all residents at Casale Monferrato, a Piedmontese town highly exposed to asbestos pollution. Unconditional multivariable logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). When considered as a categorical variable, XRCC1-399Q showed an increased OR both in heterozygotes (OR=2.08; 95% CI=1.00-4.33) and homozygotes (2.38; 95% CI=0.82-6.94), although individual ORs were not significant. When it was considered as a continuous variable OR was significant (OR=1.68; 95% CI: 1.02-2.75). When genotypes were divided into "non-risk" and "risk" genotypes, i.e. those thought to be associated with increased risk in the light of the functional significance of the variants, XRCC1-399Q (Q homozygotes+Q/R heterozygotes versus R homozygotes) had an OR=2.147 (95% CI: 1.08-4.28), whereas that of XRCC3-241T (T homozygotes+M/T heterozygotes versus M homozygotes) was 4.09 (95% CI: 1.26-13.21) and that of OGG1-326C was increased, though not significantly. None of the haplotypes showed a significantly different frequency between patients and controls. This is the first report of an association between polymorphisms in DNA repair genes and asbestos-associated MM. Our data indicate that genetic factors are involved in MM development.


Assuntos
Amianto/efeitos adversos , Reparo do DNA/genética , Mesotelioma/etiologia , Mesotelioma/genética , Neoplasias Pleurais/etiologia , Neoplasias Pleurais/genética , Polimorfismo Genético , Idoso , Sequência de Bases , Estudos de Casos e Controles , DNA Glicosilases/genética , Primers do DNA/genética , DNA de Neoplasias/genética , Proteínas de Ligação a DNA/genética , Feminino , Frequência do Gene , Haplótipos , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Proteína 1 Complementadora Cruzada de Reparo de Raio-X , Proteína Grupo D do Xeroderma Pigmentoso/genética
11.
Clin Exp Immunol ; 133(3): 430-7, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12930371

RESUMO

Triggering of the Fas receptor induces T cell apoptosis and is involved in shutting-off the immune response. Inherited defects impairing Fas function cause the autoimmune lymphoproliferative syndrome, and may play a role in other autoimmune diseases. The aim of this work was to analyse the Fas function in paediatric patients with thyroid autoimmunities. We found that T cells from 24/28 patients with Graves' disease (GD) and 12/35 patients with Hashimoto's thyroiditis (HT) displayed defective Fas function. In HT, the defect was more frequent in patients requiring replacement therapy (11/20) than in those not requiring (1/15); moreover, in untreated HT the highest defect was displayed by patients with the highest levels of autoantibodies. Fas was always expressed at normal levels and no Fas mutations were detected. Analysis of the healthy parents of seven Fas-resistant patients showed that several of them were Fas-resistant, which suggests a genetic component. Fusion of Fas-resistant T cells with the Fas-sensitive HUT78 T cell line generated Fas-resistant hybrid cells, which suggests the presence of molecules exerting a dominant negative effect on Fas function. Analysis of Fas-induced activation of caspase-8 and -9 showed decreased activity of both caspases in HT, whereas activity of caspase-9 was increased and that of caspase-8 was decreased in GD. These data suggest that heterogeneous inherited defects impairing Fas function favour the development of thyroid autoimmunities.


Assuntos
Doença de Graves/imunologia , Linfócitos T/imunologia , Tireoidite Autoimune/imunologia , Receptor fas/imunologia , Adolescente , Adulto , Idade de Início , Apoptose , Estudos de Casos e Controles , Caspase 8 , Caspase 9 , Caspases/metabolismo , Linhagem Celular , Criança , Ativação Enzimática , Feminino , Doença de Graves/genética , Humanos , Hibridomas , Ativação Linfocitária , Masculino , Linfócitos T/citologia , Linfócitos T/enzimologia , Tireoidite Autoimune/genética
13.
Hum Hered ; 52(3): 154-9, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11588399

RESUMO

Molecular analysis of 289 chromosomes has been performed in a cohort of phenylketonuria (PKU) patients whose ancestors lived in five Italian regions, Calabria, Campania, Piemonte, Puglia/Basilicata and Sicilia. Phenylalaninehydroxylase (PAH) gene mutations and minihaplotypes (combinations of PAH gene STR and VNTR systems) have been determined for 78.5 and 64%, respectively, of the chromosomes studied. 21 different minihaplotypes and 24 PKU mutations were found. Heterogeneity tests carried out for the frequencies of mutations and minihaplotypes show that the distribution of eight mutations and four minihaplotypes is statistically heterogeneous in the five Italian regions. Although the evolutionary rate of microsatellites or the age of these mutations is difficult to estimate with accuracy, our findings taken together show a genetic stratification of the Italian population. These results rule out allelic homogeneity of PKU at the molecular level between regions of Italy, yet minihaplotype data may be of practical use for a multistep approach to PAH gene genotyping.


Assuntos
Variação Genética , Haplótipos , Mutação , Alelos , Éxons , Genótipo , Humanos , Itália , Fenilalanina Hidroxilase/genética , Fenilcetonúrias/genética , Polimorfismo Genético
14.
Clin Nephrol ; 56(6): 467-74, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11770798

RESUMO

BACKGROUND: Cystinuria is an inherited disorder of cystine and dibasic amino acids transport that results in urolithiasis because of poor cystine solubility. Three cystinuria phenotypes, differentiated according to urinary amino acid excretion in obligate heterozygotes, were regarded as allelic variants of a monogenic disease. Two mutated amino acid transporter genes, however, have been recently identified as responsible for cystinuria. Mutations in the SLC3A1 gene. encoding for the heavy subunit of the transporter protein rBAT, were associated with type I cystinuria, whereas type II and III cystinuria were associated with mutations in the SLC7A9 gene, encoding for a light subunit of rBAT. Lysine and arginine metabolism have, therefore, been evaluated in cystinuria homozygotes and heterozygotes to better define the cystinuria phenotypes and their correlations with these emerging genotypes. PATIENTS AND METHODS: Lysine and arginine intestinal absorption and renal excretion were assessed by oral loading and compared to normal controls. Seven cystinuria homozygotes and 7 obligate heterozygotes belonging to the different types received alternately an oral dose of 0.5 mmol/kg body weight lysine or arginine. Plasma concentrations of lysine, arginine, ornithine (derived from rapid arginine conversion) were measured 0, 1, 2, and 3 hours after loading. Their urinary concentrations were measured in morning urine and in urine collected 0-6 hours after loading. RESULTS: Gut lysine absorption was deficient in type II and III, and normal in type I cystinuria homozygotes. Impaired arginine intestinal absorption, as well as massive lysine, arginine, and ornithine hyperexcretion were shared by all homozygotes, irrespective of the type. All heterozygotes shared normal lysine absorption, whereas arginine absorption was slightly impaired in type II and III heterozygotes, which also displayed high lysine, arginine, and ornithine urinary excretion after loading. CONCLUSIONS: Two cystinuria phenotypes, type I and non-type I, can be identified in both homozygous and heterozygous cystinuric subjects by oral loading tests with lysine and arginine. In agreement with recent molecular findings, non-type I cystinuria comprises mentioned type II and type III, which constitute allelic variants of a cystine and dibasic amino acid transport disorder distinct from type I cystinuria.


Assuntos
Sistemas de Transporte de Aminoácidos Básicos , Arginina/metabolismo , Cistinúria/genética , Cistinúria/metabolismo , Lisina/metabolismo , Fenótipo , Adolescente , Adulto , Alelos , Arginina/urina , Proteínas de Transporte/genética , Cistinúria/complicações , Feminino , Heterozigoto , Homozigoto , Humanos , Absorção Intestinal/fisiologia , Lisina/urina , Masculino , Glicoproteínas de Membrana/genética , Pessoa de Meia-Idade , Ornitina/metabolismo , Ornitina/urina , Cálculos Urinários/etiologia
15.
Hematol J ; 2(4): 220-7, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11920253

RESUMO

INTRODUCTION: In acquired immune deficiency syndrome patients, apoptosis of uninfected lymphocytes may contribute to development of immune deficiency. This process may involve recruitment of Fas by human immunodeficiency virus products. In line with this possibility, the viral envelope glycoprotein gp120 does not induce death of T cells from subjects with the autoimmune/lymphoproliferative syndrome displaying defective Fas function. This study evaluates the possibility that Fas function defects delay progression of HIV-induced immune deficiency. MATERIALS AND METHODS: The susceptibility to Fas-induced cell death was assessed on T cells from 18 'long-term non-progressor', four 'non-progressor', four 'progressor' asymptomatic HIV-1-infected, and nine AIDS patients using anti-Fas monoclonal antibodies. RESULTS: Fas-induced cell death was significantly lower in long-term non-progressors and non-progressors than in normal controls, progressors, and AIDS. The single-patient data showed that 9/18 long-term non-progressors and 3/4 non-progressors, but no progressors or AIDS were resistant to Fas. Analysis of the uninfected parents of two long-term non-progressors displaying decreased Fas-function showed that the mother of one of them and the father of the other displayed the same Fas function defect as their children. Fusion of T cells from Fas-resistant individuals with a Fas-sensitive cell line gave rise to Fas-resistant hybrid lines not carrying HIV, which suggests that the resistant phenotype is due to molecules exerting a dominant negative effect on a normal Fas system. CONCLUSION: These data suggest that Fas-resistance in long-term non-progressors may be due to inherited alterations of the Fas signaling pathway and may be a novel factor in delayed progression.


Assuntos
Síndrome da Imunodeficiência Adquirida/diagnóstico , Sobreviventes de Longo Prazo ao HIV , Receptor fas/fisiologia , Síndrome da Imunodeficiência Adquirida/genética , Anticorpos Monoclonais , Apoptose/genética , Apoptose/fisiologia , Estudos de Casos e Controles , Progressão da Doença , Saúde da Família , Humanos , Prognóstico , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Linfócitos T/metabolismo , Linfócitos T/fisiologia , Linfócitos T/virologia , Receptor fas/genética , Receptor fas/imunologia
16.
Blood Cells Mol Dis ; 26(5): 417-22, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11112378

RESUMO

Diamond-Blackfan anemia (DBA) is a congenital disease characterized by defective erythroid progenitor maturation and physical malformations. Most cases are sporadic, but dominant or, more rarely, recessive inheritance is observed in 10% of patients. Mutations in the gene encoding ribosomal protein (RP) S19 have recently been found in 25% of patients with either the dominant or the sporadic form. DBA is the first human disease due to mutations in a ribosomal structural protein. Families unlinked to this locus have also been reported. In an investigation of 23 individuals, we identified eight different mutations in 9 patients. These include five missense, one frameshift, one splice site defect, and one 4-bp insertion in the regulatory sequence. Seven mutations are new; one has so far been found in 8 patients and is a relatively common de novo event. Two mutations are predicted to generate a truncated protein. We also report the prevalence of RPS 19 mutations in the Italian DBA population, as shown by an analysis of 56 patients. No genotype-phenotype correlation was found between patients with the same mutation. The main clinical applications for molecular analysis are clinical diagnosis of patients with an incomplete form of DBA and testing of siblings of a patient with a severe form so as to avoid using those who carry a mutation and a silent phenotype as allogeneic stem cell donors.


Assuntos
Anemia de Fanconi/genética , Proteínas Ribossômicas/genética , Adulto , Substituição de Aminoácidos , Sequência de Bases , Criança , Estudos de Coortes , DNA/química , DNA/genética , Análise Mutacional de DNA , Anemia de Fanconi/patologia , Feminino , Heterogeneidade Genética , Genótipo , Humanos , Itália , Masculino , Mutagênese Insercional , Mutação , Fenótipo , Mutação Puntual , Deleção de Sequência
17.
Paediatr Drugs ; 2(5): 345-55, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11022796

RESUMO

Diamond Blackfan Anaemia (DBA) is a congenital disease characterised by defective erythroid progenitor maturation. It is usually diagnosed during the first year of life. The main clinical sign is profound isolated normochromic or macrocytic anaemia, with normal numbers and function of the other haemopoietic cells. Reticulocyte counts in patients with DBA are very low. Bone marrow reflects the defective erythropoiesis, showing a very low number of erythropoietic precursors and a reduction of erythroid burst-forming unit progenitor cells. The proliferation and differentiation of the other lineages are normal. More than one-third of patients have malformations, most often involving the upper limbs and head, and the urogenital or cardiovascular systems. However, the link between these malformations and defective erythropoiesis is unclear and a defect in a molecule acting on both early embryonic development and haematopoiesis has been proposed. Whereas most cases are sporadic, inheritance is observed in 10% of patients, with a dominant or, more rarely, recessive pattern. One locus on chromosome 19q13.2 encoding ribosomal protein S19 accounts for a quarter of patients with either the dominant or the sporadic form. Families not linked with this locus have also been described. The diagnosis of DBA may be difficult and differential diagnoses include Fanconi's anaemia and acquired erythroid aplasias. Erythrocyte adenosine deaminase levels are generally high in DBA patients, which may help in the diagnosis, but they are not pathognomic. Corticosteroids are the main treatment option in DBA and these agents induce erythropoiesis in over 60% of patients. Some patients achieve complete remission, which may be either corticosteroid-induced or spontaneous. The increased in vitro erythropoiesis occasionally induced by the addition of specific cytokines, namely interleukin (IL)-3 and stem cell factor (SCF), has suggested their use in vivo. However, few patients have responded to IL-3, whereas SCF administration, though interesting in theory, has not yet been attempted. Patients who do not respond to corticosteroids and those who have to discontinue treatment because of adverse events must rely on long term transfusions, and are thus exposed to all of the associated complications. Bone marrow or cord blood transplantation has been performed in some patients. The former approach is burdened with severe complications and high mortality.


Assuntos
Anemia de Fanconi/diagnóstico , Anemia de Fanconi/terapia , Corticosteroides/uso terapêutico , Transfusão de Sangue , Transplante de Medula Óssea , Anemia de Fanconi/etiologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/uso terapêutico , Humanos , Lactente , Interleucina-3/uso terapêutico
19.
Clin Exp Immunol ; 121(1): 53-8, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10886239

RESUMO

To ascertain whether alterations of lymphocyte switching off may be associated with clustering of autoimmune diseases in children, Fas- and C2-ceramide-induced cell death was evaluated on T cell lines derived from three patients affected by clustering of autoimmune disorders. Three patterns were found: patient 3 was resistant to Fas- and C2-ceramide, patient 1 was resistant to Fas, but sensitive to C2-ceramide, patient 2 was resistant to C2-ceramide, but sensitive to Fas. By contrast, Fas- and C2-ceramide-induced cell death was normal in five children with systemic juvenile rheumatoid arthritis, five children with insulin-dependent diabetes and 10 age-matched healthy controls. Surface expression of Fas was low in patient 1, but normal in patients 2 and 3. Together with normal Fas transcripts, patients 2 and 3 displayed a transcript 152 bp longer than the normal one retaining intron 5. Our data indicate that polyreactive autoimmune syndromes may be associated with heterogeneous alteration of the immune response switching-off system.


Assuntos
Apoptose/imunologia , Doenças Autoimunes/imunologia , Linfócitos T/citologia , Linfócitos T/imunologia , Adolescente , Apoptose/efeitos dos fármacos , Doenças Autoimunes/sangue , Doenças Autoimunes/genética , Sobrevivência Celular , Células Cultivadas , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Feminino , Humanos , Imunofenotipagem , Leucócitos Mononucleares/classificação , Leucócitos Mononucleares/imunologia , Masculino , Esfingosina/análogos & derivados , Esfingosina/farmacologia , Linfócitos T/efeitos dos fármacos , Receptor fas/genética , Receptor fas/metabolismo
20.
Blood ; 95(10): 3176-82, 2000 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-10807785

RESUMO

Fas/Apo-1 (CD95) triggers programmed cell death (PCD) and is involved in immune response control and cell-mediated cytotoxicity. In the autoimmune/lymphoproliferative syndrome (ALPS), inherited loss-of-function mutations of the Fas gene cause nonmalignant lymphoproliferation and autoimmunity. We have recently identified an ALPS-like clinical pattern (named autoimmune lymphoproliferative disease [ALD]) in patients with decreased Fas function, but no Fas gene mutation. They also displayed decreased PCD response to ceramide, triggering a death pathway partially overlapping that used by Fas, which suggests that ALD is caused by downstream alterations of the Fas signaling pathway. Decreased Fas function is also involved in tumor development, because somatic mutations hitting the Fas system may protect neoplastic cells from immune surveillance. This work assessed the inherited component of the ALD defect by evaluating Fas- and ceramide-induced T-cell death in both parents and 4 close relatives of 10 unrelated patients with ALD. Most of them (22 of 24) displayed defective Fas- or ceramide-induced (or both) cell death. Moreover, analysis of the family histories showed that frequencies of autoimmunity and cancer were significantly increased in the paternal and maternal line, respectively. Defective Fas- or ceramide-induced T-cell death was also detected in 9 of 17 autoimmune patients from 7 families displaying more than a single case of autoimmunity within first- or second-degree relatives (multiple autoimmune syndrome [MAS] patients). Autoimmune diseases displayed by ALD and MAS families included several organ-specific and systemic forms. These data suggest that ALD is due to accumulation of several defects in the same subject and that these defects predispose to development of cancer or autoimmune diseases other than ALPS/ALD.


Assuntos
Apoptose/genética , Doenças Autoimunes/genética , Predisposição Genética para Doença , Transtornos Linfoproliferativos/genética , Receptor fas/genética , Adolescente , Adulto , Idoso , Doenças Autoimunes/etiologia , Criança , Pré-Escolar , Feminino , Regulação da Expressão Gênica , Humanos , Transtornos Linfoproliferativos/etiologia , Masculino , Mutação , Neoplasias/etiologia , Neoplasias/genética , Transdução de Sinais/genética
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