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1.
Aliment Pharmacol Ther ; 47(10): 1387-1396, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29577364

RESUMO

BACKGROUND: The composite histological endpoint comprising nonalcoholic steatohepatitis (NASH) and NAFLD activity score ≥4 and advanced fibrosis (F ≥ 2) ("fibrotic NASH") is becoming an important diagnostic target in NAFLD: it is currently used to select patients for inclusion in phase III therapeutic trials and will ultimately be used to indicate treatment in clinical practice once the new drugs are approved. AIM: To develop a new blood test specifically dedicated for this new diagnostic target of interest. METHODS: Eight Hundred and forty-six biopsy-proven NAFLD patients from three centres (Angers, Nice, Antwerp) were randomised into derivation and validation sets. RESULTS: The blood fibrosis tests BARD, NFS and FIB4 had poor accuracy for fibrotic NASH with respective AUROC: 0.566 ± 0.023, 0.654 ± 0.023, 0.732 ± 0.021. In the derivation set, fibrotic NASH was independently predicted by AST, HOMA and CK18; all three were combined in the new blood test MACK-3 (hoMa, Ast, CK18) for which 90% sensitivity and 95% specificity cut-offs were calculated. In the validation set, MACK-3 had a significantly higher AUROC (0.847 ± 0.030, P ≤ 0.002) than blood fibrosis tests. Using liver biopsy in the grey zone between the two cut-offs (36.0% of the patients), MACK-3 provided excellent accuracy for the diagnosis of fibrotic NASH with 93.3% well-classified patients, sensitivity: 90.0%, specificity: 94.2%, positive predictive value: 81.8% and negative predictive value: 97.0%. CONCLUSION: The new blood test MACK-3 accurately diagnoses fibrotic NASH. This new test will facilitate patient screening and inclusion in NAFLD therapeutic trials and will enable the identification of patients who will benefit from the treatments once approved.


Assuntos
Cirrose Hepática/diagnóstico , Programas de Rastreamento/métodos , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Adulto , Idoso , Biópsia , Feminino , Testes Hematológicos/métodos , Humanos , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
2.
Leukemia ; 25(6): 939-44, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21331073

RESUMO

A simplified prognostic score is presented based on the multivariate analysis of 138 refractory/relapsed acute myeloid leukaemia (AML) patients (median age 55 years, range: 19-70) receiving a combination of intensive chemotherapy+Gemtuzumab as salvage regimen. Overall, 2-year event-free survival (EFS) and overall survival (OS) were 29±4% and 36±4%, respectively. Disease status (relapse <12 months, including refractory patients), FLT3-ITD-positive status and high-risk cytogenetics were the three strongest independent adverse prognostic factors for OS and EFS in this series. We then defined three subgroups with striking different outcomes at 2 years: no adverse factor (favourable, N=36): OS 58%, EFS 45%; one adverse factor (intermediate, N=54): OS 37%, EFS 31%; two or three adverse factors (poor, N=43): OS 12%, EFS 12% (P<10(-4), P=0.001). This new simplified Leukemia Prognostic Scoring System was then validated on an independent cohort of 111 refractory/relapsed AML patients. This new simplified prognostic score, using three clinical and biological parameters routinely applied, allow to discriminate around two third of the patients who should benefit from a salvage intensive regimen in the setting of refractory/relapsed AML patients. The other one third of the patients should receive investigational therapy.


Assuntos
Leucemia Mieloide Aguda/patologia , Prognóstico , Índice de Gravidade de Doença , Adulto , Idoso , Aminoglicosídeos/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Intervalo Livre de Doença , Gemtuzumab , Humanos , Leucemia Mieloide Aguda/diagnóstico , Pessoa de Meia-Idade , Recidiva , Terapia de Salvação/métodos , Resultado do Tratamento
4.
Leukemia ; 23(11): 1989-98, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19587702

RESUMO

Adult and child B-cell progenitor acute lymphoblastic leukemia (BCP-ALL) differ in terms of incidence and prognosis. These disparities are mainly due to the molecular abnormalities associated with these two clinical entities. A genome-wide analysis using oligo SNP arrays recently demonstrated that PAX5 (paired-box domain 5) is the main target of somatic mutations in childhood BCP-ALL being altered in 38.9% of the cases. We report here the most extensive analysis of alterations of PAX5 coding sequence in 117 adult BCP-ALL patients in the unique clinical protocol GRAALL-2003/GRAAPH-2003. Our study demonstrates that PAX5 is mutated in 34% of adult BCP-ALL, mutations being partial or complete deletion, partial or complete amplification, point mutation or fusion gene. PAX5 alterations are heterogeneous consisting in complete loss in 17%, focal deletions in 10%, point mutations in 7% and translocations in 1% of the cases. PAX5 complete loss and PAX5 point mutations differ. PAX5 complete loss seems to be a secondary event and is significantly associated with BCR-ABL1 or TCF3-PBX1 fusion genes and a lower white blood cell count.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Proteínas de Ligação a DNA/genética , Proteínas de Fusão bcr-abl/genética , Fator de Transcrição PAX5/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Proteínas Proto-Oncogênicas/genética , Adolescente , Adulto , Antineoplásicos/uso terapêutico , Benzamidas , Ensaios Clínicos Fase II como Assunto , Dosagem de Genes , Rearranjo Gênico do Linfócito T/genética , Genômica , Haplótipos , Humanos , Mesilato de Imatinib , Cadeias Pesadas de Imunoglobulinas/genética , Imunofenotipagem , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto , Piperazinas/uso terapêutico , Mutação Puntual , Fator de Transcrição 1 de Leucemia de Células Pré-B , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamento farmacológico , Prognóstico , Estudos Prospectivos , Pirimidinas/uso terapêutico , Adulto Jovem
5.
Ann Biol Clin (Paris) ; 63(6): 653-9, 2005.
Artigo em Francês | MEDLINE | ID: mdl-16330386

RESUMO

The WHO classification describes a group of myelodysplastic/myeloproliferative diseases, including a provisional entity, refractory anaemia with ringed sideroblasts (RARS) associated with marked thrombocytosis, underlining that is a provisional entity without consensus of belonging to myelodysplastic rather than to myeloproliferative syndromes. The authors report two cases with features of refractory anaemia with excess of ringed sideroblasts and marked thrombocytosis. In the first case, RARS is concomitant with thrombocytosis and fits the WHO criteria for this temporary entity. The second case is a typical RARS, who developed a thrombocytosis after several years and emphasizes that a link, at least progressive, exists between RARS and myeloproliferative disorders. The authors summed up the various situations related to secondary or primary acquired sideroblastic anaemia, likewise to primitive and reactive thrombocytosis. The cases of RARS + marked thrombocytosis reported in the literature are few in number and do not allow to settle between a particular form of myelodysplastic syndrome and a myeloproliferative disorder, a fully justified reason to classify these patients in a temporary group. To date, there is no codified therapy for this disorders.


Assuntos
Anemia Sideroblástica/classificação , Anemia Sideroblástica/complicações , Trombocitose/complicações , Idoso , Idoso de 80 Anos ou mais , Anemia Sideroblástica/patologia , Feminino , Neoplasias Hematológicas/classificação , Neoplasias Hematológicas/complicações , Humanos , Masculino , Índice de Gravidade de Doença , Trombocitose/patologia , Organização Mundial da Saúde
6.
Ann Biol Clin (Paris) ; 63(3): 317-22, 2005.
Artigo em Francês | MEDLINE | ID: mdl-15951264

RESUMO

Idiopathic hypereosinophilic syndrome is characterised by chronic hypereosinophilia leading to tissue damage, and after exclusion of reactive eosinophilia. Until recently no specific or efficient therapeutic was available. In 2003, a recurrent interstitial deletion 4q12 leading to the fusion of the FIP1L1 and PDGFRA genes was detected in hypereosinophilic syndromes. The resulting protein has constitutive tyrosine kinase activity which explains clinical and cytological remission of hypereosinophilic syndrome after treatment by a specific tyrosine kinase inhibitor, imatinib mesylate or Glivec, usually used in chronic myeloid leukaemia. Here we report a patient with hypereosinophilic syndrome associated to peculiar morphology of neutrophilic series and the 4q12 deletion. He presented clinical and haematological remission since the introduction of imatinib mesylate therapy.


Assuntos
Síndrome Hipereosinofílica/tratamento farmacológico , Síndrome Hipereosinofílica/patologia , Piperazinas/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas/uso terapêutico , Adulto , Benzamidas , Humanos , Síndrome Hipereosinofílica/etiologia , Síndrome Hipereosinofílica/genética , Mesilato de Imatinib , Masculino
7.
Leukemia ; 19(5): 792-8, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15772698

RESUMO

Idiopathic hypereosinophilic syndrome (HES) characterized by unexplained and persistent hypereosinophilia is heterogeneous and comprises several entities: a myeloproliferative form where myeloid lineages are involved with the interstitial chromosome 4q12 deletion leading to fusion between FIP1L1 and PDGFRA genes, the latter acquiring increased tyrosine kinase activity. And a lymphocytic variant, where hypereosinophilia is secondary to a primitive T lymphoid disorder demonstrated by the presence of a circulating T-cell clone. We performed molecular characterization of HES in 35 patients with normal karyotype by conventional cytogenetic analysis. TCRgamma gene rearrangements suggesting T clonality were seen in 11 (31%) patients, and FIP1L1-PDGFRA by RT-PCR in six (17%) of 35 patients, who showed no evidence of T-cell clonality. An elevated serum tryptase level was observed in FIP1L1-PDGFRA-positive patients responding to imatinib, whereas serum IL-5 levels were not elevated in T-cell associated hypereosinophilia. Sequencing FIP1L1-PDGFRA revealed scattered breakpoints in FIP1L1-exons (10-13), whereas breakpoints were restricted to exon 12 of PDGFRA. In the 29 patients without FIP1L1-PDGFRA, no activating mutation of PDGFRA/PDGFRB was detected; however; one patient responded to imatinib. FISH analysis of the 4q12 deletion was concordant with FIP1L1-PDGFRA RT-PCR data. Further investigation of the nature of FIP1L1-PDGFRA affected cells will improve the classification of HES.


Assuntos
Deleção Cromossômica , Análise Citogenética , Síndrome Hipereosinofílica/diagnóstico , Síndrome Hipereosinofílica/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , Benzamidas , Cromossomos Humanos Par 12/genética , Cromossomos Humanos Par 4/genética , Éxons , Feminino , França , Humanos , Síndrome Hipereosinofílica/tratamento farmacológico , Mesilato de Imatinib , Hibridização in Situ Fluorescente/métodos , Interleucina-5/sangue , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Piperazinas/administração & dosagem , Piperazinas/uso terapêutico , Pirimidinas/administração & dosagem , Pirimidinas/uso terapêutico , Análise de Sequência de DNA , Serina Endopeptidases/sangue , Triptases
8.
Bone Marrow Transplant ; 31(10): 909-18, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12748668

RESUMO

SUMMARY: Philadelphia chromosome (Ph) acute lymphoblastic leukemia-positive (ALL) is a subgroup of ALL with a poor prognosis. We sought to evaluate the results of allogeneic hematopoietic stem cell transplantation (HSCT) in this situation. From 1992 to 2000, 121 patients with Ph- positive ALL enrolled in one of the three main French prospective ALL chemotherapy trials and receiving allogeneic HSCT were reported to the registry of the French Society of Bone Marrow Transplantation (SFGM-TC). The median age was 35 years (range, 1-53). In all, 76 patients received HSCT in first complete remission and 45 in a more advanced disease stage. Minimal residual disease was evaluated just before the graft: 35 patients of the 52 patients in first remission had persistent BCR-ABL transcript detectable while 17 had no detectable minimal residual disease. Bone marrow and/or peripheral blood samples from 94 patients were submitted for reverse transcriptase polymerase chain reaction analysis at variable points after transplantation. Estimated 2-year survival and relapse rate for patients in CR1 were 50 and 37%, respectively, significantly better than for patients with more advanced disease (P=0.0001 and 0.01, respectively). There was no difference in survival or in relapse rates in terms of the donor used. Relapse was the most common cause of treatment failure. Hematological status at the time of transplant and the occurrence of acute graft-versus-host disease (GvHD) were the only two prognostic factors identified for relapse (P=0.02 and 0.02, respectively). Detection of BCR-ABL transcripts after transplantation had a predictive value on relapse occurrence. Finally, donor lymphocyte infusions were successfully used to treat some relapses. The graft-versus-leukemia effect of HSCT in Ph-positive ALL appears to be supported by (1) the lack of prognostic significance of pretransplant BCR-ABL transcript detection, (2) the efficacy of donor lymphocyte infusions in cases of relapse, and (3) the role of GvHD as protecting against relapse.


Assuntos
Efeito Enxerto vs Leucemia/imunologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/terapia , Transplante de Células-Tronco/efeitos adversos , Transplante Homólogo/imunologia , Doença Aguda , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Transplante de Medula Óssea , Criança , Pré-Escolar , Doença Crônica , Feminino , Seguimentos , Doença Enxerto-Hospedeiro/epidemiologia , Humanos , Lactente , Leucemia Mielogênica Crônica BCR-ABL Positiva/imunologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/mortalidade , Masculino , Pessoa de Meia-Idade , Neoplasia Residual/epidemiologia , Sociedades Médicas , Transplante de Células-Tronco/mortalidade , Taxa de Sobrevida , Fatores de Tempo , Doadores de Tecidos/estatística & dados numéricos , Resultado do Tratamento
10.
Genes Chromosomes Cancer ; 23(1): 36-43, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9713995

RESUMO

TAL1 gene deregulation is frequent in T-cell acute lymphoblastic leukemia (T-ALL) and can result from translocations involving 1p32 or, more frequently, from a cytogenetically undetectable interstitial deletion of chromosome 1. This study presents a case of T-ALL with a t(1;5)(p32;q31) involving TAL1, in which the breakpoint occurs approximately 10kbp 5' to the gene and leads to transcriptional activation and synthesis of a TAL1 protein, and extends the spectrum of recognized TAL1 gene translocations associated with T-ALL.


Assuntos
Cromossomos Humanos Par 1/genética , Cromossomos Humanos Par 5/genética , Proteínas de Ligação a DNA/genética , Leucemia-Linfoma de Células T do Adulto/genética , Fatores de Transcrição , Translocação Genética , Adulto , Fatores de Transcrição Hélice-Alça-Hélice Básicos , DNA de Neoplasias/análise , DNA de Neoplasias/genética , DNA de Neoplasias/isolamento & purificação , Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Cariotipagem , Masculino , Proteínas Proto-Oncogênicas/genética , RNA Mensageiro/análise , RNA Mensageiro/genética , Proteína 1 de Leucemia Linfocítica Aguda de Células T
11.
Blood ; 90(9): 3682-90, 1997 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-9345053

RESUMO

Monoclonal gammopathy of undetermined significance (MGUS) is a frequent condition in patients over 50 years old, that ultimately leads to multiple myeloma (MM) in 20% of patients after 20 to 35 years of follow-up. Little is known about cytogenetic changes associated with this condition. We studied 19 MGUS patients both at diagnosis and after 12 to 35 months of follow-up (mean = 26), using DNA content measurement of bone marrow plasma cells (BMPC), and a new interphase fluorescence in situ hybridization technique (FISH) allowing the simultaneous identification of monotypic BMPC (fluorescent anti light-chain antibodies) and the determination of the number of copies for two different chromosomes within the same PC nucleus (one biotin-labeled probe coupled next to texas red avidin and one FITC-labeled probe). At diagnosis of the MGUS, single interphase FISH showed at least one numeric chromosome change in 13 of 19 patients, after the use of centromeric probes directed against chromosomes no. 3, no. 7, no. 9, and no. 11. At follow-up, abnormalities found at diagnosis in 13 patients were still shown. Moreover, abnormalities occurred in three of the last six patients (trisomy for one to three different chromosomes), although no patient evolved into MM. Dual interphase FISH showed that some BMPC bore numeric changes with both probes tested whereas other BMPC bore abnormality with only one of the probes tested. In patients who showed trisomy for at least three different chromosomes, distribution of numeric changes within BMPC defined significant numbers of up to seven different BMPC clones. All these various clones were shown both at diagnosis and at follow-up. In every patient, these various clones differed only for the number of abnormalities they exhibited, and could be related to each other in a model of gradual acquisition of chromosome changes. Eventually, data reported here show that MGUS patients acquire slowly, gradually, but ineluctably chromosome changes, distributed within several related subclones. However, these changes are not related to transformation into MM: among the various clones coexisting within the same patient, a peculiar change, still to demonstrate, might develop and lead to overt MM.


Assuntos
Aberrações Cromossômicas , Transtornos Cromossômicos , Cromossomos Humanos Par 11 , Cromossomos Humanos Par 3 , Cromossomos Humanos Par 7 , Cromossomos Humanos Par 9 , Paraproteinemias/genética , Paraproteinemias/patologia , Plasmócitos/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Citogenética , Humanos , Pessoa de Meia-Idade , Paraproteinemias/diagnóstico
12.
Br J Haematol ; 98(1): 210-2, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9233586

RESUMO

We report a case of chronic myelomonocytic leukaemia (CMML), which transformed first into acute myeloblastic leukaemia (AML) and then into acute lymphoblastic leukaemia (ALL). In the AML and ALL phases, chromosome analysis showed a classic Philadelphia chromosome (Ph) t(9:22)(q34:q11). Molecular studies showed breakpoint cluster region rearrangement between exons e1 and a2 compatible with a p190(bcr/abl) breakpoint as observed in Ph-positive lymphoblastic acute leukaemia. The minor (m-bcr) rearrangement was also detected during complete remission. This observation supports a multistep pathogenesis of leukaemias, and that the p190(bcr/abl) breakpoint may influence the course of the disease.


Assuntos
Leucemia Mieloide Aguda/patologia , Leucemia Mielomonocítica Crônica/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Idoso , Transformação Celular Neoplásica , Cromossomos Humanos Par 22 , Cromossomos Humanos Par 9 , Progressão da Doença , Proteínas de Fusão bcr-abl/genética , Rearranjo Gênico , Humanos , Cariotipagem , Leucemia Mieloide Aguda/genética , Leucemia Mielomonocítica Crônica/genética , Masculino , Reação em Cadeia da Polimerase , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Translocação Genética
13.
J Pediatr Hematol Oncol ; 18(3): 285-8, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8689343

RESUMO

PURPOSE: Myelodysplastic syndrome with chromosomal translocation t(5;12)(q31-33;p12-13) and eosinophilia is a new entity recently described. Nine cases have been described in adults. We report the first pediatric case with a long follow-up (7 years). PATIENTS AND METHODS: An 8-year-old girl presented with hyperleukocytosis, eosinophilia, and no clinical symptoms. Bone marrow investigations revealed myeloid hyperplasia and clonal chromosomal translocation t(5;12)(q31;p12-13). No treatment was prescribed, but 4 years later the white blood cell count reached 144 X 10(9)/L with immature myeloid cells and splenic enlargement. Hydroxyurea chemotherapy led to a hematopoietic remission. The patient is now 16 years old and well, >7 years after the initial diagnosis. RESULTS: The association: myelodysplastic syndrome, eosinophilia and translocation t(5;12)(q31-33;p12-13), seems to be a specific hematologic disorder. Study of cases previously reported in the literature shows the most important characteristics of this disease. However, there are still a number of questions about the disease itself (especially its treatment) and the significance of the chromosomal abnormalities. CONCLUSION: This case seems to be the first report of the disease in a child and has had the longest follow-up. Other data should be collected to improve our knowledge of this hematopoietic disorder.


Assuntos
Cromossomos Humanos Par 12 , Cromossomos Humanos Par 5 , Eosinofilia/genética , Síndromes Mielodisplásicas/genética , Translocação Genética , Adulto , Criança , Mapeamento Cromossômico , Eosinofilia/complicações , Feminino , Seguimentos , Humanos , Hidroxiureia/uso terapêutico , Cariotipagem , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/complicações , Síndromes Mielodisplásicas/tratamento farmacológico
14.
Br J Haematol ; 88(2): 343-7, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7803280

RESUMO

A t(5;12)(q33;p13) translocation has been detected in two patients with myeloid disorder and eosinophilia. Six other patients with haematological disease with eosinophilia with similar translocation have been published previously. The existence of a new entity, a myeloproliferative disorder with eosinophilia and t(5;12) (q31-q33;p12-p13), is suggested by the results of the present study.


Assuntos
Cromossomos Humanos Par 12 , Cromossomos Humanos Par 5 , Eosinofilia/genética , Transtornos Mieloproliferativos/genética , Translocação Genética , Idoso , Idoso de 80 Anos ou mais , Humanos , Cariotipagem , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas
15.
Int Immunol ; 6(10): 1485-96, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7826940

RESUMO

Quantitative expression of class I genes varies widely in different tissues, during development and in some neoplastic cells. Regulatory DNA sequences controlling levels of transcription of class I genes have been characterized in the murine and swine promoters. Although some regulatory features appear to be retained in humans, most of them are not evolutionary conserved. In this study, we identify novel DNA sequences and factors which contribute to the regulation of the human HLA-A11 gene. Two activator elements (-155 to -91 and -335 to -206) and one negative element (-172 to -156), distinct from those previously described are mapped within 335 bp upstream of exon 1 of the human HLA-A11 gene. Various nuclear factors bind to these regulatory elements, some of which are cell restricted or interact with evolutionary divergent regulatory sequences of the human class I gene promoter. Two of the five DNA-binding sites characterized in this work bind at least two proteins which compete for the occupancy of their site. The identification of these new regulatory elements provides a more comprehensive basis for the understanding of physiological or pathological modulation of MHC class I transcription in humans.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Antígenos HLA-A/genética , Proteínas Nucleares/metabolismo , Sequências Reguladoras de Ácido Nucleico/fisiologia , Sequência de Bases , Cloranfenicol O-Acetiltransferase/genética , Regulação para Baixo/genética , Elementos Facilitadores Genéticos/fisiologia , Antígeno HLA-A11 , Células HeLa , Humanos , Dados de Sequência Molecular , Regiões Promotoras Genéticas/fisiologia , Transfecção , Regulação para Cima/genética
16.
Rev Prat ; 43(11): 1354-7, 1993 Jun 01.
Artigo em Francês | MEDLINE | ID: mdl-8235382

RESUMO

Iron deficiency anaemia is characterized by the conjunction of a microcytic, typically are generative anaemia and a biochemical syndrome in which sideropoenia is associated with transferrin increase. It is usually due to a chronic exsudative gastrointestinal or gynaecological bleeding. Diagnosing the mechanism of anaemia is easy in most cases, but difficulties arise from association with a pathology, such as chronic inflammatory syndrome, disturbing the haematological or biochemical data. The prognosis of iron deficiency anaemia depends on its cause. Treatment is aetiological (the cause of chronic bleeding is suppressed) and symptomatic (the body's iron reserves are quickly restored).


Assuntos
Anemia Hipocrômica , Anemia Hipocrômica/diagnóstico , Anemia Hipocrômica/etiologia , Anemia Hipocrômica/fisiopatologia , Anemia Hipocrômica/terapia , Diagnóstico Diferencial , Humanos , Ferro/sangue
17.
Proc Natl Acad Sci U S A ; 89(8): 3488-92, 1992 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-1565643

RESUMO

Class I antigens encoded in the major histocompatibility complex (MHC) (HLA in man, H-2 in the mouse) play a key role in the recognition of target cells by cytolytic T lymphocytes. Tumor cells frequently do not express class I MHC molecules, which strongly suggests that down-regulation of the latter facilitates escape of tumor cells from immune surveillance. The expression of class I MHC genes is tightly regulated. An enhancer element, conserved in the promoters of mouse and human MHC genes, has been shown to be important for mouse class I MHC gene expression. At least two related regulatory factors (KBF1 and NF-kappa B) bind to this regulatory element. We have analyzed the binding of these factors in cellular extracts of 23 human tumor cell lines displaying various levels of class I mRNA and surface expression. In this panel, combined deficiency of KBF1- and NF-kappa B-like DNA-binding activities was frequent among the class I-negative cell lines and correlated with the absence of class I mRNA. A few cell lines that lack KBF1 binding activity still display NF-kappa B-like activity and express normal levels of MHC class I mRNA. These results suggest (i) that, in the absence of KBF1, NF-kappa B or a related factor promotes MHC class I gene transcription; and (ii) that a combined defect in KBF1/NF-kappa B DNA-binding activity can cause a pleiotropic defect in class I gene expression, which may facilitate tumor progression.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Elementos Facilitadores Genéticos , Genes MHC Classe I , Antígenos de Histocompatibilidade Classe I/genética , NF-kappa B/metabolismo , Neoplasias/imunologia , Fatores de Transcrição/metabolismo , Anticorpos Monoclonais , Sequência de Bases , Linhagem Celular , Membrana Celular/imunologia , Sondas de DNA , Feminino , Expressão Gênica , Humanos , Dados de Sequência Molecular , Subunidade p50 de NF-kappa B , Neoplasias/genética , Sondas de Oligonucleotídeos , Ligação Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
19.
Int J Cancer Suppl ; 6: 138-45, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1906051

RESUMO

Tumor cells frequently show a lack of surface class-I major histocompatibility complex (MHC) antigen expression. These molecules are key recognition structures for immune rejection of tumor cells and their absence at the surface of tumor cells could favor the progression of tumors. We have analyzed the transcriptional mechanisms that could lead to suppression of MHC-class-I expression in human tumor cell K562. The expression of MHC-class-I genes is highly controlled by regulatory factors interacting with an enhancer sequence upstream of MHC-class-I genes. In this report we show that DNA binding activity of 2 regulatory factors, KBFI and NF-kappa B, known to be essential for constitutive expression of MHC-class-I genes, is deficient in nuclear extracts from K562 cells. Induction of class-I gene expression at the surface of tumor cells by interferon-gamma (IFN-gamma) and tumor necrosis factor alpha (TNF-alpha) shows that TNF-alpha can act in synergy with IFN-gamma to induce DNA binding of both factors NF-kappa B and KBFI to the class-I gene enhancer and that this induction of transcriptional factors is correlated with enhancement of MHC-class-I mRNA transcription and cell-surface antigen expression.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Elementos Facilitadores Genéticos , Regulação Neoplásica da Expressão Gênica , Genes MHC Classe I , Transcrição Gênica , Anticorpos Monoclonais , Sequência de Bases , Northern Blotting , Linhagem Celular , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/fisiologia , Sondas de DNA , Expressão Gênica/efeitos dos fármacos , Células HeLa/imunologia , Humanos , Interferon gama/farmacologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/imunologia , Dados de Sequência Molecular , Sondas de Oligonucleotídeos , Reação em Cadeia da Polimerase/métodos , RNA Neoplásico/genética , RNA Neoplásico/isolamento & purificação , Proteínas Recombinantes , Transcrição Gênica/efeitos dos fármacos , Fator de Necrose Tumoral alfa/farmacologia
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