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1.
Leukemia ; 32(2): 383-390, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28761118

RESUMO

The Dutch-Belgian Cooperative Trial Group for Hematology Oncology Group-65/German-speaking Myeloma Multicenter Group-HD4 (HOVON-65/GMMG-HD4) phase III trial compared bortezomib (BTZ) before and after high-dose melphalan and autologous stem cell transplantation (HDM, PAD arm) compared with classical cytotoxic agents prior and thalidomide after HDM (VAD arm) in multiple myeloma (MM) patients aged 18-65 years. Here, the long-term follow-up and data on second primary malignancies (SPM) are presented. After a median follow-up of 96 months, progression-free survival (censored at allogeneic transplantation, PFS) remained significantly prolonged in the PAD versus VAD arm (hazard ratio (HR)=0.76, 95% confidence interval (95% CI) of 0.65-0.89, P=0.001). Overall survival (OS) was similar in the PAD versus VAD arm (HR=0.89, 95% CI: 0.74-1.08, P=0.24). The incidence of SPM were similar between the two arms (7% each, P=0.73). The negative prognostic effects of the cytogenetic aberration deletion 17p13 (clone size ⩾10%) and renal impairment at baseline (serum creatinine >2 mg dl-1) on PFS and OS remained abrogated in the PAD but not VAD arm. OS from first relapse/progression was similar between the study arms (HR=1.02, P=0.85). In conclusion, the survival benefit with BTZ induction/maintenance compared with classical cytotoxic agents and thalidomide maintenance is maintained without an increased risk of SPM.


Assuntos
Bortezomib/administração & dosagem , Mieloma Múltiplo/tratamento farmacológico , Adolescente , Adulto , Idoso , Aberrações Cromossômicas/efeitos dos fármacos , Feminino , Seguimentos , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Masculino , Melfalan/uso terapêutico , Pessoa de Meia-Idade , Mieloma Múltiplo/mortalidade , Mieloma Múltiplo/patologia , Prognóstico , Intervalo Livre de Progressão , Talidomida/uso terapêutico , Transplante Autólogo/métodos , Adulto Jovem
3.
Leukemia ; 31(10): 2048-2056, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28196983

RESUMO

Recent developments in sequencing technologies led to the discovery of a novel form of genomic instability, termed chromothripsis. This catastrophic genomic event, involved in tumorigenesis, is characterized by tens to hundreds of simultaneously acquired locally clustered rearrangements on one chromosome. We hypothesized that leukemias developing in individuals with Ataxia Telangiectasia, who are born with two mutated copies of the ATM gene, an essential guardian of genome stability, would show a higher prevalence of chromothripsis due to the associated defect in DNA double-strand break repair. Using whole-genome sequencing, fluorescence in situ hybridization and RNA sequencing, we characterized the genomic landscape of Acute Lymphoblastic Leukemia (ALL) arising in patients with Ataxia Telangiectasia. We detected a high frequency of chromothriptic events in these tumors, specifically on acrocentric chromosomes, as compared with tumors from individuals with other types of DNA repair syndromes (27 cases total, 10 with Ataxia Telangiectasia). Our data suggest that the genomic landscape of Ataxia Telangiectasia ALL is clearly distinct from that of sporadic ALL. Mechanistically, short telomeres and compromised DNA damage response in cells of Ataxia Telangiectasia patients may be linked with frequent chromothripsis. Furthermore, we show that ATM loss is associated with increased chromothripsis prevalence in additional tumor entities.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/fisiologia , Ataxia Telangiectasia/genética , Proteínas de Neoplasias/fisiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Adolescente , Ataxia Telangiectasia/complicações , Proteínas Mutadas de Ataxia Telangiectasia/deficiência , Proteínas Mutadas de Ataxia Telangiectasia/genética , Criança , Pré-Escolar , Cromossomos Humanos/ultraestrutura , Cromotripsia , Reparo do DNA/genética , DNA de Neoplasias/genética , Feminino , Genoma Humano , Instabilidade Genômica , Humanos , Hibridização in Situ Fluorescente , Masculino , Mutação , Proteínas de Neoplasias/deficiência , Proteínas de Neoplasias/genética , Neoplasias/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/etiologia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , RNA Neoplásico/genética , Análise de Sequência de DNA , Análise de Sequência de RNA , Encurtamento do Telômero/genética , Transcriptoma
4.
Leukemia ; 31(8): 1735-1742, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28025584

RESUMO

Immunoglobulin light chain (AL) amyloidosis is characterized by tissue deposition of amyloid fibers derived from immunoglobulin light chain. AL amyloidosis and multiple myeloma (MM) originate from monoclonal gammopathy of undetermined significance. We wanted to characterize germline susceptibility to AL amyloidosis using a genome-wide association study (GWAS) on 1229 AL amyloidosis patients from Germany, UK and Italy, and 7526 healthy local controls. For comparison with MM, recent GWAS data on 3790 cases were used. For AL amyloidosis, single nucleotide polymorphisms (SNPs) at 10 loci showed evidence of an association at P<10-5 with homogeneity of results from the 3 sample sets; some of these were previously documented to influence MM risk, including the SNP at the IRF4 binding site. In AL amyloidosis, rs9344 at the splice site of cyclin D1, promoting translocation (11;14), reached the highest significance, P=7.80 × 10-11; the SNP was only marginally significant in MM. SNP rs79419269 close to gene SMARCD3 involved in chromatin remodeling was also significant (P=5.2 × 10-8). These data provide evidence for common genetic susceptibility to AL amyloidosis and MM. Cyclin D1 is a more prominent driver in AL amyloidosis than in MM, but the links to aggregation of light chains need to be demonstrated.


Assuntos
Amiloidose/genética , Estudo de Associação Genômica Ampla , Cadeias Leves de Imunoglobulina/metabolismo , Mieloma Múltiplo/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Ciclina D1/fisiologia , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
5.
Leukemia ; 29(10): 2015-23, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25971364

RESUMO

Mutations of the tumor suppressor p53 lead to chemotherapy resistance and a dismal prognosis in chronic lymphocytic leukemia (CLL). Whereas p53 targets are used to identify patient subgroups with impaired p53 function, a comprehensive assessment of non-coding RNA targets of p53 in CLL is missing. We exploited the impaired transcriptional activity of mutant p53 to map out p53 targets in CLL by small RNA sequencing. We describe the landscape of p53-dependent microRNA/non-coding RNA induced in response to DNA damage in CLL. Besides the key p53 target miR-34a, we identify a set of p53-dependent microRNAs (miRNAs; miR-182-5p, miR-7-5p and miR-320c/d). In addition to miRNAs, the long non-coding RNAs (lncRNAs) nuclear enriched abundant transcript 1 (NEAT1) and long intergenic non-coding RNA p21 (lincRNA-p21) are induced in response to DNA damage in the presence of functional p53 but not in CLL with p53 mutation. Induction of NEAT1 and lincRNA-p21 are closely correlated to the induction of cell death after DNA damage. We used isogenic lymphoma cell line models to prove p53 dependence of NEAT1 and lincRNA-p21. The current work describes the p53-dependent miRNome and identifies lncRNAs NEAT1 and lincRNA-p21 as novel elements of the p53-dependent DNA damage response machinery in CLL and lymphoma.


Assuntos
Apoptose , Leucemia Linfocítica Crônica de Células B/genética , MicroRNAs/genética , RNA Longo não Codificante/genética , Proteína Supressora de Tumor p53/genética , Idoso , Idoso de 80 Anos ou mais , Western Blotting , Proliferação de Células , Imunoprecipitação da Cromatina , Dano ao DNA , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/metabolismo
6.
Leukemia ; 29(8): 1721-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25787915

RESUMO

We aimed at demonstrating non-inferiority of bortezomib/cyclophosphamide/dexamethasone (VCD) compared to bortezomib/doxorubicin/dexamethasone (PAd) induction therapy with respect to very good partial response rates or better (⩾VGPR) in 504 newly diagnosed, transplant-eligible multiple myeloma patients. VCD was found to be non-inferior to PAd with respect to ⩾VGPR rates (37.0 versus 34.3%, P=0.001). The rates of progressive disease (PD) were 0.4% (VCD) versus 4.8% (PAd; P=0.003). In the PAd arm, 11 of 12 patients with PD had either renal impairment (creatinine ⩾2 mg/dl) at diagnosis or the cytogenetic abnormality gain 1q21, whereas no PD was observed in these subgroups in the VCD arm. Leukocytopenia/neutropenia (⩾3°) occurred more frequently in the VCD arm (35.2% versus 11.3%, P<0.001). Neuropathy rates (⩾2°) were higher in the PAd group (14.9 versus 8.4%, P=0.03). Serious adverse events, both overall and those related to thromboembolic events, were higher in the PAd group (32.7 versus 24.0%, P=0.04 and 2.8 versus 0.4%, P=0.04). Stem cell collection was not impeded by VCD. VCD is as effective as PAd in terms of achieving ⩾VGPR rates with fewer PD and has a favorable toxicity profile. Therefore, VCD is preferable to PAd as induction therapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Mieloma Múltiplo/tratamento farmacológico , Adulto , Idoso , Ácidos Borônicos/administração & dosagem , Bortezomib , Ciclofosfamida/administração & dosagem , Dexametasona/administração & dosagem , Doxorrubicina/administração & dosagem , Feminino , Seguimentos , Mobilização de Células-Tronco Hematopoéticas , Humanos , Quimioterapia de Indução , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/mortalidade , Mieloma Múltiplo/patologia , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Pirazinas/administração & dosagem , Indução de Remissão , Taxa de Sobrevida
8.
Leukemia ; 28(9): 1902-8, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24535407

RESUMO

Previous studies demonstrated the relevance of focal lesions (FL) in whole-body magnetic resonance imaging (wb-MRI) at the initial workup of patients with smoldering multiple myeloma (SMM). The aim of this study was to assess the effects of longitudinal wb-MRIs on progression into multiple myeloma (MM). Sixty-three patients with SMM were analyzed who received at least two wb-MRIs for follow-up before progression into MM. Radiological progressive disease (MRI-PD) was defined as detection of new FL or increase in diameter of existing FL and a novel or progressive diffuse infiltration. Radiological stable disease (MRI-SD) was defined by no change compared with the prior MRI. Patients were followed-up every 3-6 months, including a serological and clinical evaluation. One Hundred and eighty-two wb-MRIs were analyzed. MRI-PD occurred in 31 patients (49%), and 25 (40%) patients developed MM. MRI-PD was highly significantly associated with progression into MM, regardless of findings at the initial MRI. In multivariate analysis, MRI-PD remained a risk factor, independent of relevant baseline parameters like serum monoclonal protein or ⩾95% aberrant plasma cells in the bone marrow. Patients with MRI-SD had no higher risk of progression, even when FL were present at the initial MRI. Therefore, MRI is suitable for the follow-up of patients with SMM.


Assuntos
Imageamento por Ressonância Magnética/métodos , Mieloma Múltiplo/patologia , Adulto , Idoso , Humanos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Estudos Retrospectivos
9.
Oncogene ; 33(27): 3506-18, 2014 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-23955078

RESUMO

The incidence of skin cancer is increasing worldwide and cutaneous squamous cell carcinomas (SCCs) are associated with considerable morbidity and mortality, particularly in immunosuppressed individuals ('carcinomatous catastrophy'). Yet, molecular mechanisms are still insufficiently understood. Besides ultraviolet (UV)-indicative mutations, chromosomal aberrations are prominent. As telomeres are essential in preserving chromosome integrity, and telomere erosion as well as aberrant spatial telomere distribution contribute to genomic instability, we first established telomere length profiles across the whole tissue and identified normal skin (10/30) harboring discrete epidermal sites (stem cell territories) of evenly short telomeres. Precancerous actinic keratoses (AKs) (17) and SCCs (27) expressed two telomere phenotypes: (i) tissue-wide evenly short to intermediate and (ii) longer and tissue-wide heterogeneous telomere lengths, suggesting two modes of initiation, with one likely to originate in the epidermal stem cells. Although tumor histotype, location, patient gender or age failed to distinguish the two SCC telomere phenotypes, as did telomerase activity, we found a trend for a higher degree of aberrant p53 and cyclin D1 expression with long/heterogeneous telomeres. In addition, we established an association for the short/homogeneous telomeres with a simpler and the heterogeneous telomeres with a more complex karyotype correlating also with distinct chromosomal changes. SCCs (13) from renal transplant recipients displayed the same telomere dichotomy, suggesting that both telomere subtypes contribute to 'carcinomatous catastrophy' under immunosuppression by selecting for a common set (3, 9p and 17q) and subtype-specific aberrations (e.g., 6p gain, 13q loss). As a second mechanism of telomere-dependent genomic instability, we investigated changes in telomere distribution with its most severe form of telomeric aggregates (TAs). We identified a telomere length-independent but progression-dependent increase in cells with small telomere associations in AKs (17/17) and additional TAs in SCCs (24/32), basal cell carcinomas (30/31) and malignant melanomas (15/15), and provide evidence for a reactive oxygen species-dependent mechanism in this UV-induced telomere organization-dependent genomic instability.


Assuntos
Carcinoma de Células Escamosas/classificação , Carcinoma de Células Escamosas/genética , Neoplasias Cutâneas/classificação , Neoplasias Cutâneas/genética , Telômero/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/enzimologia , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Criança , Ciclina D1/metabolismo , Progressão da Doença , Instabilidade Genômica/efeitos da radiação , Humanos , Masculino , Melanoma/enzimologia , Melanoma/genética , Melanoma/patologia , Pessoa de Meia-Idade , Neoplasias Cutâneas/enzimologia , Neoplasias Cutâneas/patologia , Telomerase/metabolismo , Telômero/efeitos da radiação , Proteína Supressora de Tumor p53/metabolismo , Raios Ultravioleta , Adulto Jovem
10.
Oncogene ; 32(20): 2586-91, 2013 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-22751129

RESUMO

AVEN has been identified as an inhibitor of apoptosis, which binds to the adaptor protein, APAF-1, and thereby prevents apoptosome formation and mitochondrial apoptosis. Recent data have demonstrated high expression levels of AVEN messenger RNA in acute leukemias as well as a positive correlation between AVEN mRNA overexpression and poor prognosis in childhood acute lymphoblastic leukemia. On the basis of these data, we investigated the potential involvement of AVEN in tumorigenesis. First, we confirmed the overexpression of AVEN in T-cell acute lymphoblastic leukemia/lymphoma (T-ALL) patient samples. We then established a transgenic mouse model with T-cell-specific overexpression of AVEN, with which we demonstrated the oncogenic cooperation of AVEN with heterozygous loss of p53. Finally, we used a subcutaneous xenograft mouse model to show that AVEN knockdown in the T-ALL cell lines, MOLT-4 and CCRF-CEM, and in the acute myeloblastic leukemia cell line, Kasumi-1, leads to a halt in tumor growth owing to the increased apoptosis and decreased proliferation of tumor cells. Collectively, our data demonstrate that the anti-apoptotic molecule, AVEN, functions as an oncoprotein in hematopoietic neoplasms.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Reguladoras de Apoptose/genética , Proteínas de Membrana/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Sequência de Bases , Linhagem Celular Tumoral , Regulação Leucêmica da Expressão Gênica , Técnicas de Silenciamento de Genes , Genes p53 , Humanos , Linfoma de Células T/genética , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Dados de Sequência Molecular , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Timócitos/fisiologia , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Ther Umsch ; 69(12): 697-701, 2012 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-23188782

RESUMO

Fever of unknown origin (FUO) is a common medical diagnosis by exclusion. In these cases, fever is the predominant symptom of an underlying disease. We describe the case of a 60-year old patient with FUO. Intensive search for the causative disease was carried out. Unfortunately all the investigations remained fruitless. Eventually, the patient was discharged with the diagnosis of common variable immunodeficiency, based on hypogammaglobulinemia and Cytomegalovirus replication. Two weeks after discharge, the patient presented in the outpatient clinic with the typical symptoms of giant cell arteriitis (GCA). The diagnosis was confirmed by a repeated ultrasound imaging and biopsy findings. The clinical condition of the patient improved rapidly after beginning of treatment with steroids. This case illustrates the importance of a longitudinal observation of patients presenting with FUO if the diagnosis remains unclear after intensive investigations.


Assuntos
Febre de Causa Desconhecida/etiologia , Arterite de Células Gigantes/complicações , Arterite de Células Gigantes/diagnóstico , Biópsia , Diagnóstico Diferencial , Arterite de Células Gigantes/patologia , Humanos , Masculino , Artérias Temporais/patologia
12.
Clin Genet ; 79(5): 489-94, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-20681991

RESUMO

The short stature homeobox (SHOX) gene is located in the pseudoautosomal region 1 of both sex chromosomes. Haploinsufficiency of SHOX leads to different phenotypes ranging from isolated short stature to Léri-Weill syndrome characterized by short stature, mesomelia and Madelung deformity. We describe a family with a SHOX deletion originally located on the Y chromosome and transmitted from father to daughter by crossover during meiosis. The male index patient presented with short stature, mesomelia and mild Madelung deformity. His father had a normal height but slightly disproportionate short legs. The sister of the index patient presented with marked Madelung deformity and normal height. A deletion of the SHOX gene was identified in the male index patient, his father and his sister. Metaphase fluorescence in situ hybridization (FISH) analyses showed a deletion of the SHOX gene on the Y chromosomes of the index patient and his father, and on the X chromosome of his sister, indicating that a meiotic crossover of the SHOX gene region between the X and Y chromosomes had occurred. The pseudoautosomal region 1 is a known recombination 'hot spot' in male meiosis. Published genetic maps indicate high recombination frequency of ∼40% for SHOX in male meiosis leading to pseudoautosomal inheritance.


Assuntos
Transtornos Cromossômicos/genética , Pré-Escolar , Feminino , Transtornos do Crescimento/genética , Proteínas de Homeodomínio/genética , Humanos , Hibridização in Situ Fluorescente , Masculino , Osteocondrodisplasias/genética , Linhagem , Proteína de Homoeobox de Baixa Estatura
13.
Oncogene ; 28(44): 3866-79, 2009 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-19718049

RESUMO

Pathogenesis of multiple myeloma is associated with an aberrant expression of pro-proliferative, pro-angiogenic and bone-metabolism-modifying factors by malignant plasma cells. Given the frequently long time span from diagnosis of early-stage plasma cell dyscrasias to overt myeloma and the mostly low proliferation rate of malignant plasma cells, we hypothesize these to similarly express a novel class of inhibitory factors of potential prognostic relevance. Bone morphogenic proteins (BMPs) represent possible candidates as they inhibit proliferation, stimulate bone formation and have an effect on the survival of cancer patients. We assessed the expression of BMPs and their receptors by Affymetrix DNA microarrays (n=779) including CD138-purified primary myeloma cell samples (n=635) of previously untreated patients. BMP6 is the only BMP expressed by malignant and normal plasma cells. Its expression is significantly lower in proliferating myeloma cells, myeloma cell lines or plasmablasts. BMP6 significantly inhibits the proliferation of myeloma cell lines, survival of primary myeloma cells and in vitro angiogenesis. A high BMP6 expression in primary myeloma cell samples delineates significantly superior overall survival for patients undergoing high-dose chemotherapy independent of conventional prognostic factors (International Staging System (ISS) stage, beta(2) microglobulin).


Assuntos
Biomarcadores Tumorais/biossíntese , Proteína Morfogenética Óssea 6/biossíntese , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/mortalidade , Proteínas de Neoplasias/biossíntese , Neovascularização Patológica/metabolismo , Neovascularização Patológica/mortalidade , Intervalo Livre de Doença , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Mieloma Múltiplo/patologia , Neovascularização Patológica/patologia , Análise de Sequência com Séries de Oligonucleotídeos , Plasmócitos , Taxa de Sobrevida
14.
J Clin Pathol ; 62(10): 892-5, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19541684

RESUMO

BACKGROUND: Papillary renal cell tumours (RCTs) have been described as a genetic entity. Recently, papillary RCTs have been divided into small (type 1) and large (type 2) cell tumours. Subsequent DNA analyses have resulted in controversial data regarding putative genetic changes marking type 1 and type 2 tumours. AIM: The aim of this study was to improve the original description that papillary RCT is a genetic entity regardless of the phenotypic variation. METHODS: DNA from 163 papillary RCTs, including 82 multiplex tumours from eight hereditary cases, was analysed for copy number changes by chromosomal comparative genomic hybridisation (CGH) and/or for allelic changes at chromosomes 7 and 17 by microsatellite analysis. The results of the genetic analysis were compared with the cytological characteristics of the tumours. RESULTS: The results showed alterations of chromosomes 7 and 17 at similar frequencies in papillary RCTs with characteristics ranging from small to large cell, nuclear grade 1 to 3, and 3 mm to 16 cm diameter. CONCLUSION: Trisomies of chromosomes 7 and 17 are specific genetic alterations in papillary RCTs irrespective of their size, grade and cellular differentiation.


Assuntos
Carcinoma Papilar/genética , Cromossomos Humanos Par 17/genética , Cromossomos Humanos Par 7/genética , Neoplasias Renais/genética , Trissomia , Carcinoma Papilar/patologia , Hibridização Genômica Comparativa/métodos , DNA de Neoplasias/genética , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Humanos , Neoplasias Renais/patologia , Repetições de Microssatélites/genética , Fenótipo
15.
Bone Marrow Transplant ; 40(11): 1033-7, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17891186

RESUMO

Lack of CD56 expression was reported to be associated with a poor prognosis in multiple myeloma (MM) patients treated with conventional chemotherapy. Aim of our retrospective study was to analyse whether CD56 expression on MM cells reveals as a prognostic factor in patients treated with high-dose chemotherapy. MM cells of 99 patients prior to treatment with high-dose chemotherapy were analysed for CD56 expression by flow cytometry. Multivariable analysis of event-free survival in these patients showed no statistically significant difference between the CD56(-) (n=28) and the CD56(+) (n=71) group. The lack of CD56 expression on MM cells of these patients correlated significantly with the presence of translocation (11;14) (t(11;14)) (estimated correlation coefficient=0.655 95%, confidence interval (0.481; 0.779)). In summary, our results indicate that lack of CD56 expression on MM cells is not a prognostic marker in patients treated with high-dose chemotherapy, but is associated with t(11;14).


Assuntos
Antígeno CD56/metabolismo , Melfalan/administração & dosagem , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/genética , Agonistas Mieloablativos/administração & dosagem , Adulto , Idoso , Biomarcadores , Antígeno CD56/genética , Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 17/genética , Intervalo Livre de Doença , Relação Dose-Resposta a Droga , Feminino , Transplante de Células-Tronco Hematopoéticas , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/patologia , Estudos Retrospectivos , Translocação Genética/genética , Transplante Autólogo
16.
Oncogene ; 26(7): 1088-97, 2007 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-16909113

RESUMO

The molecular pathogenesis of pleomorphic xanthoastrocytoma (PXA), a rare astrocytic brain tumor with a relatively favorable prognosis, is still poorly understood. We characterized 50 PXAs by comparative genomic hybridization (CGH) and found the most common imbalance to be loss on chromosome 9 in 50% of tumors. Other recurrent losses affected chromosomes 17 (10%), 8, 18, 22 (4% each). Recurrent gains were identified on chromosomes X (16%), 7, 9q, 20 (8% each), 4, 5, 19 (4% each). Two tumors demonstrated amplifications mapping to 2p23-p25, 4p15, 12q13, 12q21, 21q21 and 21q22. Analysis of 10 PXAs with available high molecular weight DNA by high-resolution array-based CGH indicated homozygous 9p21.3 deletions involving the CDKN2A/p14(ARF)/CDKN2B loci in six tumors (60%). Interphase fluorescence in situ hybridization to tissue sections confirmed the presence of tumor cells with homozygous 9p21.3 deletions. Mutational analysis of candidate genes on 9q, PTCH and TSC1, revealed no mutations in PXAs with 9q loss and no evidence of TSC1 promoter methylation. However, PXAs consistently showed low TSC1 transcript levels. Taken together, our study identifies loss of chromosome 9 as the most common chromosomal imbalance in PXAs and suggests important roles for homozygous CDKN2A/p14(ARF)/CDKN2B deletion as well as low TSC1 mRNA expression in these tumors.


Assuntos
Astrocitoma/genética , Deleção Cromossômica , Cromossomos Humanos Par 9/genética , Inibidor de Quinase Dependente de Ciclina p15/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Deleção de Genes , Proteína Supressora de Tumor p14ARF/genética , Proteínas Supressoras de Tumor/deficiência , Adolescente , Adulto , Criança , Pré-Escolar , Inibidor de Quinase Dependente de Ciclina p15/deficiência , Inibidor p16 de Quinase Dependente de Ciclina/deficiência , Feminino , Homozigoto , Humanos , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/biossíntese , Proteína 1 do Complexo Esclerose Tuberosa , Proteína Supressora de Tumor p14ARF/deficiência , Proteínas Supressoras de Tumor/biossíntese , Proteínas Supressoras de Tumor/genética
17.
Leukemia ; 19(7): 1198-206, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15902298

RESUMO

Overexpression of BCR-ABL and P-glycoprotein (Pgp) are two of the known mechanisms of imatinib resistance. As combination therapy may allow to overcome drug resistance, we investigated the effect of combination treatment with imatinib and 17-allylamino-17-demethoxygeldanamycin (17-AAG), a heat-shock protein 90 (Hsp90) inhibitor, on different imatinib-sensitive and imatinib-resistant CML cell lines. In imatinib-sensitive cells, combination index (CI) values obtained using the method of Chou and Talalay indicated additive (CI=1) or marginally antagonistic (CI>1) effects following simultaneous treatment with imatinib and 17-AAG. In imatinib-resistant cells both drugs acted synergistically (CI<1). In primary chronic-phase CML cells additive or synergistic effects of the combination of imatinib plus 17-AAG were discernible. Annexin V/propidium iodide staining showed that the activity of imatinib plus 17-AAG is mediated by apoptosis. Combination treatment with imatinib plus 17-AAG was more effective in reducing the BCR-ABL protein level than 17-AAG alone. Monotherapy with 17-AAG decreased P-glycoprotein activity, which may increase intracellular imatinib levels and contribute to the sensitization of CML cells to imatinib. The results suggest that combination of imatinib and 17-AAG may be useful to overcome imatinib resistance in a clinical setting.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/efeitos dos fármacos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Proteínas de Fusão bcr-abl/biossíntese , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Piperazinas/farmacologia , Proteínas Tirosina Quinases/biossíntese , Pirimidinas/farmacologia , Rifabutina/análogos & derivados , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/fisiologia , Apoptose/efeitos dos fármacos , Benzamidas , Benzoquinonas , Proliferação de Células/efeitos dos fármacos , Sinergismo Farmacológico , Proteínas de Fusão bcr-abl/genética , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Humanos , Mesilato de Imatinib , Hibridização in Situ Fluorescente , Lactamas Macrocíclicas , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Fosforilação , Proteínas Tirosina Quinases/análise , RNA Mensageiro/genética , Rifabutina/farmacologia , Ensaio Tumoral de Célula-Tronco
18.
Endocr Relat Cancer ; 10(4): 437-50, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14713256

RESUMO

Neuroendocrine tumours (NETs) originate in tissues that contain cells derived from the embryonic neural crest, neuroectoderm and endoderm. Thus, NETs occur at many sites in the body, although the majority occur within the gastro-entero-pancreatic axis and can be subdivided into those of foregut, midgut and hindgut origin. Amongst these, only those of midgut origin are generally argentaffin positive and secrete serotonin, and hence only these should be referred to as carcinoid tumours. NETs may occur as part of complex familial endocrine cancer syndromes, such as multiple endocrine neoplasia type 1 (MEN1), although the majority occur as non-familial (i.e. sporadic) isolated tumours. Molecular genetic studies have revealed that the development of NETs may involve different genes, each of which may be associated with several different abnormalities that include point mutations, gene deletions, DNA methylation, chromosomal losses and chromosomal gains. Indeed, the foregut, midgut and hindgut NETs develop via different molecular pathways. For example, foregut NETs have frequent deletions and mutations of the MEN1 gene, whereas midgut NETs have losses of chromosome 18, 11q and 16q and hindgut NETs express transforming growth factor-alpha and the epidermal growth factor receptor. Furthermore, in lung NETs, a loss of chromosome 3p is the most frequent change and p53 mutations and chromosomal loss of 5q21 are associated with more aggressive tumours and poor survival. In addition, methylation frequencies of retinoic acid receptor-beta, E-cadherin and RAS-associated domain family genes increase with the severity of lung NETs. Thus the development and progression of NETs is associated with specific genetic abnormalities that indicate the likely involvement of different molecular pathways.


Assuntos
Tumor Carcinoide/genética , Tumores Neuroendócrinos/genética , Aberrações Cromossômicas , Metilação de DNA , Feminino , Humanos , Perda de Heterozigosidade , Masculino , Oncogenes , Linhagem , Proteínas Proto-Oncogênicas/genética
19.
Cancer Genet Cytogenet ; 130(1): 79-83, 2001 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-11672779

RESUMO

Data concerning cytogenetic features of childhood ependymoma are rare. In this article, a gain of 1q was identified as the sole alteration in a primary childhood infratentorial ependymoma by comparative genomic hybridization (CGH). A recurrence of this brain tumor was studied using multiplex-fluorescence in situ hybridization (M-FISH) in addition to CGH and G-banding analysis. In accordance with the primary tumor, a gain of 1q corresponding to an isochromosome 1q was observed indicating an early event in the tumor development. Furthermore, M-FISH classified several other rearranged chromosomes including 6q and 17p that have previously been found to be involved in the development and progression of childhood ependymoma.


Assuntos
Neoplasias Encefálicas/genética , Aberrações Cromossômicas , Cromossomos Humanos Par 1 , Ependimoma/genética , Pré-Escolar , Humanos , Hibridização in Situ Fluorescente , Masculino
20.
Oncogene ; 20(29): 3835-44, 2001 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-11439347

RESUMO

Telomere maintenance is regarded as a key mechanism in overcoming cellular senescence in tumor cells and in most cases is achieved by the activation of telomerase. However there is at least one alternative mechanism of telomere lengthening (ALT) which is characterized by heterogeneous and elongated telomeres in the absence of telomerase activity (TA). We evaluated the prevalence of TA, gene expression of telomerase subunits and ALT in relation to telomere morphology and function in matrix producing bone tumors and in osteosarcoma cell lines and present evidence of a direct association of ALT with telomere dysfunction and chromosomal instability. Telomere fluorescence in situ hybridization (T-FISH) in ALT cells revealed elongated and shortened telomeres, partly in unusual configurations and loci, dicentric marker chromosomes and signal-free chromosome ends. Free ends give rise to end-to-end associations and may induce breakage-fusion-bridge cycles resulting in an increased number of complex chromosomal rearrangements, as detected by multiplex-FISH (M-FISH). We propose that ALT cannot be seen as an equivalent to telomerase activity in telomere maintenance. Its association with telomere dysfunction and chromosomal instability may have major implications for tumor progression.


Assuntos
Neoplasias Ósseas/genética , Osteossarcoma/genética , Telômero , Adulto , Neoplasias Ósseas/patologia , Humanos , Hibridização in Situ Fluorescente , Pessoa de Meia-Idade , Osteossarcoma/patologia , Telomerase/metabolismo , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
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