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1.
Ann Hematol ; 95(6): 863-70, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27001309

RESUMO

Evans syndrome (ES) is defined by the combination (either simultaneous or sequential) of immune thrombocytopenia (ITP) and autoimmune haemolytic anaemia (AIHA). When related to secondary conditions, ES may arise in patients with chronic lymphocytic leukaemia (CLL), which is frequently associated to autoimmune cytopenias (AIC). We analysed 25 patients with ES secondary to CLL, which were identified from a large series of consecutive patients with CLL, diagnosed and followed up in two institutions. They represented 2.9 % of the whole series. Thirteen patients presented with concurrent ITP and AIHA (simultaneous ES), while others developed the two AIC sequentially. Occurrence of ES was associated with unfavourable biological prognostic factors like ZAP-70 expression, unmutated immunoglobulin heavy chain variable region gene status, 17-p13 deletion and TP53 gene mutations. Of note, the majority of patients with ES (66 %) had stereotyped B cell receptor configuration. Most patients had short-lasting remissions and required second-line treatments to control the autoimmune manifestations of ES. Patients with ES were associated with inferior survival compared to patients not developing AIC, especially when ES developed early in the course of CLL, although the reduced survival was not confirmed by multivariate analysis. In conclusion, ES secondary to CLL is a difficult-to-treat complication, characterised by adverse biological features and clinical outcome.


Assuntos
Anemia Hemolítica Autoimune/diagnóstico , Anemia Hemolítica Autoimune/etiologia , Leucemia Linfocítica Crônica de Células B/complicações , Leucemia Linfocítica Crônica de Células B/diagnóstico , Trombocitopenia/diagnóstico , Trombocitopenia/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anemia Hemolítica Autoimune/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Feminino , Seguimentos , Humanos , Leucemia Linfocítica Crônica de Células B/terapia , Masculino , Pessoa de Meia-Idade , Prednisona/administração & dosagem , Prognóstico , Estudos Retrospectivos , Trombocitopenia/terapia , Resultado do Tratamento , Vincristina/administração & dosagem
2.
Haematologica ; 99(5): 881-7, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24415628

RESUMO

Most patients affected by chronic lymphocytic leukemia are diagnosed by flow cytometry. Several immunophenotypic markers have been identified as significant and independent prognostic variables, especially from retrospective cohorts. However, while attractive because their detection is inexpensive and feasible in most laboratories, only few have been validated by independent series. The expression of leukocyte-associated immunoglobulin-like receptor-1 (also known as LAIR1, LAIR-1 or CD305), an inhibitor of B-cell receptor-mediated signaling, has been reported to be lacking in high-risk chronic lymphocytic leukemia. However, its correlation with biological variables and its prognostic significance remain unknown. We investigated 311 consecutive patients, prospectively enrolled since 2007. Methods for studying patients were standardized and included clinical assessment, immunophenotype, fluorescence in situ hybridization, and status of immunoglobulin heavy chain variable region genes. Overall, 22.1% of patients had Binet stage B or C disease, 38.5% had unmutated immunoglobulin genes, 15.1% had high-risk cytogenetic abnormalities, 23.4% were CD38(+), 37.8% CD49d(+), and 59.8% LAIR1(+). Expression of LAIR1 was inversely related to that of CD38 (P=0.0005), but was not associated with CD49d expression (P=0.96). A significantly lower expression of LAIR1 was observed in patients with Binet stage B or C disease (P=0.023), and in the presence of high-risk cytogenetic abnormalities (P=0.048) or unmutated immunoglobulin heavy chain variable region genes (P<0.0001). At univariate analysis LAIR1(+) was significantly associated with longer time to first treatment (P=0.0002). This favorable effect of LAIR1(+) was confirmed by multivariate analysis (hazard ratio=2.1, P=0.03 for LAIR1). Our results indicate that LAIR1 expression is a reliable and inexpensive marker capable of independently predicting time to first treatment in newly diagnosed unselected patients with chronic lymphocytic leukemia.


Assuntos
Leucemia Linfocítica Crônica de Células B/metabolismo , Receptores Imunológicos/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Aberrações Cromossômicas , Progressão da Doença , Feminino , Citometria de Fluxo , Seguimentos , Expressão Gênica , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Imunofenotipagem , Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/mortalidade , Masculino , Pessoa de Meia-Idade , Mutação , Estadiamento de Neoplasias , Avaliação de Resultados da Assistência ao Paciente , Prognóstico , Estudos Prospectivos , Receptores Imunológicos/genética
3.
Hematol Oncol ; 32(1): 22-30, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23861036

RESUMO

Trisomy 12 (+12) is the third most frequent cytogenetic aberration in chronic lymphocytic leukaemia (CLL) retrievable both as the sole chromosomal abnormality or in association with additional alterations. NOTCH1 mutations are known to be more prevalent among +12 patients, whereas mutations of FBXW7, a gene involved in NOTCH1 degradation, that lead to the constitutional activation of NOTCH1 have not been investigated in this setting. We analyzed a unicentric cohort of 44 +12 patients with CLL for mutations of TP53, NOTCH1 and FBXW7 genes, and we correlated them with B-cell receptor (BCR) configurations. FBXW7, TP53 and NOTCH1 mutations were identified in 4.5%, 6.8% and 18.2% of patients, respectively. FBXW7 and NOTCH1 mutations appeared in a mutually exclusive fashion, suggesting that both aberrations might affect the same biological pathway. We found that 44.1% of +12 CLL patients had stereotyped B-cell receptors, which is significantly higher than that observed in patients with CLL and no +12 (27%, p = 0.01). Subsets #1, #8, #10, #28 and #59 were the most represented stereotyped patterns, and IGHV4-39*01 was the gene configuration most commonly used. There was a significantly higher risk for Richter's syndrome (RS) transformation in patients with NOTCH1 or FBXW7 mutations, with four of the seven (57%) patients developing RS and characterized at least by one of the two abnormalities. These observations suggest that, similarly to the aberrations of NOTCH1, FBXW7 gene mutations may also result in cell proliferation and evasion from apoptosis in patients with +12 CLL. Together with the extremely high frequency of stereotyped BCRs and RS transformation, these abnormalities appear to cluster in these CLL patients with additional chromosome 12, suggesting a connection with the prognosis of the disease.


Assuntos
Cromossomos Humanos Par 12 , DNA de Neoplasias/genética , Rearranjo Gênico do Linfócito B , Leucemia Linfocítica Crônica de Células B/genética , Mutação , Trissomia , Idoso , Sequência de Aminoácidos , Animais , Proteínas de Ciclo Celular/genética , Transformação Celular Neoplásica/genética , Células Clonais/patologia , Sequência Conservada , Análise Mutacional de DNA , Progressão da Doença , Proteínas F-Box/genética , Proteína 7 com Repetições F-Box-WD , Feminino , Rearranjo Gênico de Cadeia Pesada de Linfócito B , Genes de Imunoglobulinas , Genes p53 , Humanos , Hibridização in Situ Fluorescente , Interfase/genética , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Células-Tronco Neoplásicas/patologia , Receptor Notch1/genética , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Especificidade da Espécie , Síndrome , Ubiquitina-Proteína Ligases/genética
4.
Am J Hematol ; 88(4): 277-82, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23450508

RESUMO

The immunoglobulin heavy chain variable (IGHV) gene mutational status represents a major prognostic marker in chronic lymphocytic leukemia (CLL). Usually, the prognostic implications of IGHV gene analysis can be reliably ascertained but, occasionally, double productive rearrangements have been detected. Clinical presentation and biological features of such cases are unknown. Sixty patients with morphologically and phenotypically monoclonal CLL but double productive IGHV rearrangements were retrospectively identified by mRNA analysis from three Hematology Institutions. Clinical and biological features and survival of these 60 patients were compared with a control group of patients with CLL and single IGHV rearrangement. A prospective registry was used to assess the epidemiology of double productive IGHV among incidental patients with CLL. Using standard criteria to define IGHV-mutated (M) or unmutated (U) cases, 39 of the 60 patients (65%) with double productive IGHV rearrangement had concordant status (23 MM, 16 UU), while 21 (35%) had discordant IGHV status. As compared with M patients, the MM ones had lower CD38 expression, more favorable cytogenetics and more indolent clinical behavior. Cases with UU had similar characteristics of U patients. Discordant cases presented with adverse prognostic features and had an aggressive clinical behavior requiring early treatment, similar to U patients. The prevalence of double IGHV was 3.1%. Patients with CLL with double concordant mutational status (MM or UU) have a clinical course similar to that of the corresponding single IGHV status, while those exhibiting discordant status represent a high risk population. This may help correct stratification within clinical trials.


Assuntos
Genes de Cadeia Pesada de Imunoglobulina , Cadeias Pesadas de Imunoglobulinas/genética , Região Variável de Imunoglobulina/genética , Leucemia Linfocítica Crônica de Células B/genética , Mutação , Sistema de Registros , ADP-Ribosil Ciclase 1/genética , ADP-Ribosil Ciclase 1/imunologia , Idoso , Feminino , Expressão Gênica , Humanos , Cadeias Pesadas de Imunoglobulinas/imunologia , Região Variável de Imunoglobulina/imunologia , Imunofenotipagem , Leucemia Linfocítica Crônica de Células B/imunologia , Leucemia Linfocítica Crônica de Células B/mortalidade , Masculino , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/imunologia , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos , Análise de Sobrevida
5.
Am J Hematol ; 88(1): 32-6, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23115077

RESUMO

The development of autoimmune hemolytic anemia (AIHA) in patients with chronic lymphocytic leukemia (CLL) is associated with specific biological features. The occurrence of AIHA was hereby investigated in a retrospective series of 585 CLL patients with available immunoglobulin heavy chain variable (IGHV) gene status. AIHA occurred in 73 patients and was significantly associated with an IGHV unmutated (UM) status (P < 0.0001) and unfavorable [del(17)(p13) and del(11)(q23)] cytogenetic lesions (P < 0.0001). Stereotyped HCDR3 sequences were identified in 29.6% of cases and were similarly represented among patients developing or not AIHA; notably, subset #3 was associated with a significantly higher risk of AIHA than the other patients (P = 0.004). Multivariate analysis showed that UM IGHV, del(17)(p13) and del(11)(q23), but not stereotyped subset #3, were the strongest independent variables associated with AIHA. Based on these findings, we generated a biological risk score for AIHA development according to the presence of none (low risk), one (intermediated risk), or two (high risk) of the independent risk factors. Overall, our data indicate that UM IGHV status and/or unfavorable cytogenetic lesions are associated with the risk of developing secondary AIHA in CLL patients and suggest a possible role of specific stereotyped B-cell receptor subsets in a proportion of cases.


Assuntos
Anemia Hemolítica Autoimune/genética , Cadeias Pesadas de Imunoglobulinas/genética , Leucemia Linfocítica Crônica de Células B/genética , Receptores de Antígenos de Linfócitos B/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Anemia Hemolítica Autoimune/etiologia , Deleção Cromossômica , Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 17/genética , Feminino , Seguimentos , Humanos , Leucemia Linfocítica Crônica de Células B/complicações , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco
6.
Haematologica ; 97(1): 56-63, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21933855

RESUMO

BACKGROUND: B-cell chronic lymphocytic leukemia is a clinically heterogeneous disease; some patients rapidly progress and die within a few years of diagnosis, whereas others have a long life expectancy with minimal or no treatment. Telomere length and telomerase levels have been proposed as prognostic factors; however, very few cases have been characterized for both parameters and no study has analyzed the prognostic value of the telomere/telomerase profile. DESIGN AND METHODS: One hundred and seventy-three cases of chronic lymphocytic leukemia were characterized for telomere lengths and telomerase levels by real-time polymerase chain reaction. Data were correlated with established prognostic markers, IGVH mutational status and chromosomal aberrations, and clinical outcome. RESULTS: Telomere lengths were inversely correlated with telomerase levels (r(s) = -0.213; P = 0.012), and most of the cases of chronic lymphocytic leukemia with high levels (above median) of telomerase had short (below median) telomeres (P = 0.0001). Telomerase levels were higher and telomeres were shorter in unmutated IGVH cases than in mutated IGVH ones (P<0.0001). Chronic lymphocytic leukemias with 11q, 17p deletion or 12 trisomy had significantly higher levels of telomerase and shorter telomeres than those with no chromosomal aberration or the sole 13q deletion (P < 0.001). Telomere length/telomerase level profiles identified subgroups of patients with different clinical outcomes (P < 0.0001), even within the subsets of chronic lymphocytic leukemia defined by IGVH mutational status or chromosomal aberrations. Short telomere/high telomerase profile was independently associated with more rapid disease progression. CONCLUSIONS: Comprehensive analyses of telomeres, telomerase, chromosomal aberrations, and IGVH mutational status delineate groups of chronic lymphocytic leukemias with distinct biological characteristics and clinical outcomes. The telomere/telomerase profile may be particularly useful in refining the prognosis of chronic lymphocytic leukemia patients with mutated IGVH and no high-risk chromosomal aberrations.


Assuntos
Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/metabolismo , Telomerase/metabolismo , Homeostase do Telômero , ADP-Ribosil Ciclase 1/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Aberrações Cromossômicas , Feminino , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Leucemia Linfocítica Crônica de Células B/classificação , Leucemia Linfocítica Crônica de Células B/mortalidade , Masculino , Pessoa de Meia-Idade , Mutação , Prognóstico , Análise de Sobrevida , Telomerase/genética , Transcrição Gênica , Proteína-Tirosina Quinase ZAP-70/metabolismo
8.
Oncotarget ; 6(21): 18653-63, 2015 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-26087198

RESUMO

The relation between Epstein-Barr virus (EBV) DNA load and clinical course of patients with chronic lymphocytic leukemia (CLL) is unknown. We assessed EBV DNA load by quantitative PCR at CLL presentation in mononuclear cells (MNC) of 220 prospective patients that were enrolled and followed-up in two major Institutions. In 20 patients EBV DNA load was also assessed on plasma samples. Forty-one age-matched healthy subjects were tested for EBV DNA load on MNC. Findings were validated in an independent retrospective cohort of 112 patients with CLL. EBV DNA load was detectable in 59%, and high (≥2000 copies/µg DNA) in 19% of patients, but it was negative in plasma samples. EBV DNA load was significantly higher in CLL patients than in healthy subjects (P < .0001). No relation was found between high EBV load and clinical stage or biological variables, except for 11q deletion (P = .004), CD38 expression (P = .003), and NOTCH1 mutations (P = .05). High EBV load led to a 3.14-fold increase in the hazard ratio of death and to a shorter overall survival (OS; P = .001). Poor OS was attributable, at least in part, to shorter time-to-first-treatment (P = .0008), with no higher risk of Richter's transformation or second cancer. Multivariate analysis selected high levels of EBV load as independent predictor of OS after controlling for confounding clinical and biological variables. EBV DNA load at presentation is an independent predictor of OS in patients with CLL.


Assuntos
DNA Viral/genética , Infecções por Vírus Epstein-Barr/tratamento farmacológico , Herpesvirus Humano 4/genética , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Carga Viral/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Células Cultivadas , DNA Viral/sangue , Infecções por Vírus Epstein-Barr/sangue , Infecções por Vírus Epstein-Barr/virologia , Feminino , Herpesvirus Humano 4/fisiologia , Interações Hospedeiro-Patógeno , Humanos , Estimativa de Kaplan-Meier , Leucemia Linfocítica Crônica de Células B/sangue , Leucemia Linfocítica Crônica de Células B/virologia , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/virologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Mutação , Avaliação de Resultados em Cuidados de Saúde/métodos , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Reação em Cadeia da Polimerase , Prognóstico , Modelos de Riscos Proporcionais
9.
Thromb Res ; 105(2): 135-8, 2002 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-11958803

RESUMO

We report a new family with autosomal recessive von Willebrand disease (VWD) in which the propositus was compound heterozygous for a missense mutation in exon 42 (G7085T, C2362F) and a C-->A splice site mutation in intron 13 of the von Willebrand factor (VWF) gene. The propositus had factor VIII:C approximately equal to 20 IU/dl, VWF antigen 5-7 IU/dl and ristocetin cofactor activity <3-7 IU/dl. The bleeding time (BT) was markedly prolonged (>15 min). Haplotype analysis and mutation screening were conducted by polymerase chain reaction (PCR)-based methodology. Each mutation appeared to be linked to a haplotype that was identical to the haplotype previously detected in subjects in the Veneto region carrying these mutations, suggesting a founder effect. In the propositus' family six subjects were heterozygotes for the C2362F mutation and five were heterozygotes for the splice site mutation. None of the heterozygotes had suffered from significant bleeding. The mutation C2362F and the splice site mutation in intron 13 are commonly observed in subjects with recessive von Willebrand disease in the Veneto region. These mutations are truly recessive and cause bleeding only in the compound heterozygous or homozygous state.


Assuntos
Genes Recessivos , Mutação , Sítios de Splice de RNA/genética , Doenças de von Willebrand/genética , Fator de von Willebrand/genética , Adulto , Pré-Escolar , Éxons , Saúde da Família , Feminino , Efeito Fundador , Haplótipos , Hemorragia/genética , Heterozigoto , Humanos , Íntrons , Masculino , Mutação de Sentido Incorreto , Linhagem , Doenças de von Willebrand/sangue , Fator de von Willebrand/análise
10.
Clin Cancer Res ; 18(7): 1870-8, 2012 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-22322667

RESUMO

PURPOSE: To assess biologic features related to the development of immune thrombocytopenia (ITP) in patients with chronic lymphocytic leukemia (CLL). EXPERIMENTAL DESIGN: We retrospectively analyzed 463 patients with CLL with available immunoglobulin heavy-chain variable (IGHV) gene status and B-cell receptor (BCR) configuration [heavy-chain complementary-determining region 3 (HCDR3)], of whom thirty-six developed ITP, according to previously defined criteria. Most of them had available cytogenetic analysis. RESULTS: We observed a significant association between ITP occurrence and IGHV unmutated gene status (P < 0.0001), unfavorable cytogenetic lesions (P = 0.005), and stereotyped HCDR3 (P = 0.006). The more frequent stereotyped HCDR3 subsets were #1 (IGHV1-5-7/IGHD6-19/IGHJ4; 16 of 16 unmutated) and #7 (IGHV1-69 or IGHV3-30/IGHD3-3/IGHJ6; 13 of 13 unmutated), both being significantly more represented among patients developing ITP (P = 0.003 and P = 0.001, respectively). Moreover, restricting the analysis to unmutated patients, subset #7 confirmed its independent significant association with the occurrence of ITP (P = 0.013). Both unmutated IGHV mutational status, del(11)(q23) and stereotyped BCR were significantly associated with shorter time to ITP development (P < 0.0001, P = 0.02, and P = 0.005, respectively) than other patients. CONCLUSION: Our data suggest that patients with CLL and peculiar BCR conformations are at higher risk of developing secondary ITP and that stereotyped BCR may be involved in the pathogenesis of this complication.


Assuntos
Regiões Determinantes de Complementaridade/imunologia , Leucemia Linfocítica Crônica de Células B/imunologia , Receptores de Antígenos de Linfócitos B/imunologia , Trombocitopenia/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Regiões Determinantes de Complementaridade/genética , Feminino , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias Pesadas de Imunoglobulinas/imunologia , Região Variável de Imunoglobulina/genética , Região Variável de Imunoglobulina/imunologia , Estimativa de Kaplan-Meier , Leucemia Linfocítica Crônica de Células B/complicações , Leucemia Linfocítica Crônica de Células B/genética , Masculino , Pessoa de Meia-Idade , Mutação , Modelos de Riscos Proporcionais , Receptores de Antígenos de Linfócitos B/genética , Estudos Retrospectivos , Medição de Risco/estatística & dados numéricos , Fatores de Risco , Trombocitopenia/complicações , Trombocitopenia/genética
13.
Haematologica ; 87(11): 1157-64, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12414345

RESUMO

BACKGROUND AND OBJECTIVES: Several polymerase chain reaction (PCR)-based techniques for tracking minimal residual disease (MRD) in B-lymphoproliferative disorders have been recently proposed. These procedures show significant variation in sensitivity and specificity. We describe an alternative assay based on fluorescent PCR combined with capillary electrophoresis and GeneScan analysis, to identify the monoclonal immunoglobulin heavy chain (IgH) rearrangement in multiple myeloma (MM) and to provide a semi-quantitative evaluation of MRD by limiting dilutions. DESIGN AND METHODS: Different sets of family specific primers derived from the leader region and from the framework-1 of IgH were used, with a unique reverse fluorescent primer JH. The malignant clone was identified by GeneScan and sequenced. Two tumor primers, mapping in the complementarity determining regions CDRII and CDRIII, were designed for each patient. A comparison between the nested-PCR approach and direct fluorescent PCR was performed for three patients in complete clinical remission after autologous or allogeneic bone marrow transplantation. RESULTS: Thirty-six consecutive patients with MM were screened and monoclonality was identified in about 70% of the cases. Molecular MRD evaluation was performed in 18 patients using tumor primers. This method allowed identification of 1 neoplastic cell among 10(4)-10(6) normal cells. In three cases, negative by nested-PCR and agarose gel electrophoresis, gene scanning showed persistence of the neoplastic clone, despite the negativity of the immunofixation. INTERPRETATION AND CONCLUSIONS: Capillary electrophoresis of fluorescent fragments with gene scanning provides a simple, rapid and reproducible method to detect IgH rearrangement and to evaluate MRD. Furthermore, the sensitivity reached is up to 1 log higher than that of the conventional approach with nested-PCR, even though two steps of specificity are maintained.


Assuntos
Cadeias Pesadas de Imunoglobulinas/genética , Técnicas de Diagnóstico Molecular/normas , Mieloma Múltiplo/diagnóstico , Adulto , Idoso , Primers do DNA/normas , Eletroforese Capilar/normas , Fluorescência , Rearranjo Gênico , Genes de Imunoglobulinas , Humanos , Pessoa de Meia-Idade , Técnicas de Diagnóstico Molecular/métodos , Neoplasia Residual/diagnóstico , Reação em Cadeia da Polimerase/métodos , Reação em Cadeia da Polimerase/normas , Sensibilidade e Especificidade
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