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1.
Leuk Res ; 127: 107040, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36801702

RESUMO

We compared the efficacy of azacitidine (AZA) and decitabine (DEC) in elderly patients with untreated AML, diagnosed according to WHO criteria. In the two groups, we evaluated complete remission (CR), overall survival (OS) and disease free survival (DFS). The AZA and DEC groups included 139 and 186 patients, respectively. To minimize the effects of treatment selection bias, adjustments were made using the propensity-score matching method, which yielded 136 patient pairs. In the AZA and DEC cohort, median age was 75 years in both, (IQR, 71-78 and 71-77), median WBCc at treatment onset 2.5 × 109/L (IQR, 1.6-5.8) and 2.9 × 109/L (IQR, 1.5-8.1), median bone marrow (BM) blast count 30% (IQR, 24-41%) and 49% (IQR, 30-67%), 59 (43%) and 63 (46%) patients had a secondary AML, respectively. Karyotype was evaluable in 115 and 120 patients: 80 (59%) and 87 (64%) had intermediate-risk, 35 (26%) and 33 (24%) an adverse risk karyotype, respectively. Median number of cycles delivered was 6 (IQR, 3.0-11.0) and 4 (IQR, 2.0-9.0), CR rate was 24% vs 29%, median OS and 2-year OS rates 11.3 (95% CI 9.5-13.8) vs 12.0 (95% CI 7.1-16.5) months and 20% vs 24%, respectively. No differences in CR and OS were found within the following subgroup: intermediate- and adverse-risk cytogenetic, frequency of WBCc at treatment ≥ 5 × 10^9 L and < 5 × 10^9/L, de novo and secondary AML, BM blast count < and ≥ 30%. Median DFS for AZA and DEC treated patients was 9.2 vs 12 months, respectively. Our analysis indicates similar outcomes with AZA compared to DEC.


Assuntos
Azacitidina , Leucemia Mieloide Aguda , Humanos , Idoso , Azacitidina/uso terapêutico , Decitabina/uso terapêutico , Resultado do Tratamento , Intervalo Livre de Doença , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
3.
Mycoses ; 62(3): 252-260, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30565742

RESUMO

Invasive fungal infections (IFI) of the Central Nervous System (IFI-CNS) and Paranasal Sinuses (IFI-PS) are rare, life-threatening infections in haematologic patients, and their management remains a challenge despite the availability of new diagnostic techniques and novel antifungal agents. In addition, analyses of large cohorts of patients focusing on these rare IFI are still lacking. Between January 2010 and December 2016, 89 consecutive cases of Proven (53) or Probable (36) IFI-CNS (71/89) and IFI-PS (18/89) were collected in 34 haematological centres. The median age was 40 years (range 5-79); acute leukaemia was the most common underlying disease (69%) and 29% of cases received a previous allogeneic stem cell transplant. Aspergillus spp. were the most common pathogens (69%), followed by mucormycetes (22%), Cryptococcus spp. (4%) and Fusarium spp. (2%). The lung was the primary focus of fungal infection (48% of cases). The nervous system biopsy was performed in 10% of IFI-CNS, and a sinus biopsy was performed in 56% of IFI-PS (P = 0.03). The Galactomannan test on cerebrospinal fluid has been performed in 42% of IFI-CNS (30/71), and it was positive in 67%. Eighty-four pts received a first-line antifungal therapy with Amphotericine B in 58% of cases, Voriconazole in 31% and both in 11%. Moreover, 58% of patients received 2 or more lines of therapy and 38% were treated with a combination of 2 or more antifungal drugs. The median duration of antifungal therapy was 60 days (range 5-835). A surgical intervention was performed in 26% of cases but only 10% of IFI-CNS underwent neurosurgical intervention. The overall response rate to antifungal therapy (complete or partial response) was 57%, and 1-year overall survival was 32% without significant differences between IFI-CNS and IFI-PS. The overall mortality was 69% but the IFI attributable mortality was 33%. Mortality of IFI-CNS/PS remains high but, compared to previous historical data, it seems to be reduced probably due to the availability of newer antifungal drugs. The results arising from this large contemporary cohort of cases may allow a more effective diagnostic and therapeutic management of these very rare IFI complications in haematologic patients.


Assuntos
Antifúngicos/uso terapêutico , Infecções Fúngicas do Sistema Nervoso Central/epidemiologia , Desbridamento , Fungos/classificação , Fungos/isolamento & purificação , Neoplasias Hematológicas/complicações , Sinusite/epidemiologia , Adolescente , Adulto , Idoso , Infecções Fúngicas do Sistema Nervoso Central/microbiologia , Infecções Fúngicas do Sistema Nervoso Central/terapia , Líquido Cefalorraquidiano/microbiologia , Criança , Pré-Escolar , Estudos Epidemiológicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Seios Paranasais/microbiologia , Sinusite/microbiologia , Sinusite/terapia , Análise de Sobrevida , Resultado do Tratamento , Adulto Jovem
4.
Reumatismo ; 57(3): 174-9, 2005.
Artigo em Italiano | MEDLINE | ID: mdl-16258601

RESUMO

BACKGROUND: Recently, several studies have demonstrated the presence of circulating endothelial progenitors (CEPs) responsible for angiogenesis. Notably, these cells are able to migrate to ischemic tissues and differentiate in situ in mature endothelial cells. Aim of this study was to assess the presence of CEPs in the peripheral blood of patients with Sistemic Sclerosis (SSc) and evaluate their significance as an attempt of re-vascularization MATERIAL AND METHODS: Samples of peripheral blood from 40 healthy subjects and 56 patients with SSc were studied. Five-parameter, 3-color flow cytometry was performed with a FACScan. CEPs were defined as CD45 negative, CD34 and CD133 positive. In addition, plasma levels of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) were detected by commercial ELISA (R&D Systems). RESULTS: Levels of CEPs (CD133+/CD34+/CD45-) were significantly higher in patients with SSc in comparison to HC (P = 0.01). No correlation was found between CEPs and any clinical parameter of disease neither activity score. CEPs were significantly higher in the group of patients with early disease, while their number decreased in the late phases of disease. Plasma levels of VEGF, but not bFGF, were significantly higher in SSc in comparison to HC (P<0.001) but no correlation was found between VEGF concentrations and CEP number. CONCLUSIONS: The presence of CEPs in patients with SSc suggest that sclerodermic hypoxic tissues could induce the mobilization of bone-marrow derived cells in an attempt to provided new vessels, in the early phase of the disease, at least.


Assuntos
Células Endoteliais , Escleroderma Sistêmico/sangue , Células-Tronco , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica/etiologia , Escleroderma Sistêmico/imunologia
5.
Leuk Lymphoma ; 46(9): 1345-51, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16109613

RESUMO

Increased angiogenesis has been demonstrated to be a significant prognostic factor in many solid tumors. In the oncohematological setting, it has been associated with myelodysplastic syndromes (MDS), chronic myeloid leukemia, acute lymphoid, and myeloid leukemias. Recently, increased circulating endothelial cells (CECs) have been associated with breast cancer and non-Hodgkin lymphoma (NHL). Based on these premises we analysed total and activated CECs, and endothelial precursors (CEPs) in 50 MDS patients and 20 healthy donors. CECs and CEPs were quantified by flow cytometry. CEC levels were compared with bone marrow (BM) microvessel density (MVD). In addition, some angiogenic factors, namely vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF) and soluble VEGF-Receptor2 (VEGFR2), were tested in the sera from 25 MDS patients. Total, activated CECs and CEPs were significantly increased in MDS when compared to control group (p<0.0001); whereas in the MDS cases no association was found with French--American--British (FAB), International Prognostic Scoring System (IPSS) subtypes or survival. Patients with higher CECs also showed higher MVD. Among the cytokines analysed, sVEGFR2 was significantly higher in the lower IPSS risk classes, while the levels of bFGF directly correlated with total and activated CECs. Taken together these data strengthen the hypothesis of a possible role of angiogenesis in MDS pathogenesis.


Assuntos
Células Endoteliais/fisiologia , Síndromes Mielodisplásicas/sangue , Neovascularização Patológica , Adulto , Idoso , Biomarcadores , Medula Óssea/irrigação sanguínea , Contagem de Células , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/patologia , Células-Tronco/fisiologia
6.
Reumatismo ; 57(1): 29-35, 2005.
Artigo em Italiano | MEDLINE | ID: mdl-15776144

RESUMO

OBJECTIVE: Circulating endothelial cells (CECs) have been described in different conditions with vascular injury. Vascular abnormalities play a key role in the pathogenesis of Systemic Sclerosis (SSc). The aim of our study was to look for the presence of CECs in SSc patients and to evaluate their clinical significance. METHODS: We studied 52 SSc patients and 40 healthy controls (HC). Five-parameter, 3-color flow cytometry was performed with a FACScan. CECs were defined as CD45 negative, CD31 and P1H12 positive, and activated CECs as CD45 negative and P1H12, CD62, or CD106 positive. RESULTS: Total and activated CEC counts were significantly higher in SSc patients when compared with HC and positively correlated with disease activity score. We found a significant association between CECs and disease activity; as regard with organ involvement, CEC number correlate with the severity of pulmonary hypertension. CONCLUSIONS: Raised counts of CECs may represent direct evidence of active vascular disease in SSc as regard as visceral involvement, the association between CECs and pulmonary hypertension suggest a relevant role for CECs as a marker of prominent endothelial involvement.


Assuntos
Células Endoteliais , Escleroderma Sistêmico/sangue , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
7.
Leuk Lymphoma ; 44(9): 1495-501, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14565650

RESUMO

UNLABELLED: We retrospectively analyzed the incidence of thrombotic and infectious complications in relation with the use of central venous catheters (CVCs), in a series of patients with hematological malignancies and low platelet and leucocyte counts. PATIENTS AND METHODS: 126 patients with hematological malignancies were analyzed. A total of 207 CVCs were implanted: 137 centrally (CICCs) and 70 peripherally (PICCs). The median duration of the CVCs was 19 days for a total of 4051 catheter-days. Antithrombotic prophylaxis was unfractionated heparin (UFH), 2,500 IU daily by 24 h continuous infusion in 169 CVCs, low molecular weight heparin (LMWH), 3,800 IU daily by single bolus intravenous injection (i.v.) in 21 and warfarin in one. No prophylaxis was given in 16 CVCs. Thrombotic complications developed in 15.5% of the CVCs (7.9 events/1000 catheter days), and the frequency of infectious complications was 10.6% (5.2 events/1000 catheter days). On multivariate analysis thromboses were more frequent and earlier with PICCs than CICCs (p = 0.0001), and in patients on UFH (16.6%) than in LMWH prophylaxis (4.7%), but the last difference was not statistically significant. In conclusions the incidence of thrombotic complications in our series was comparable to that observed in non-thrombocytopenic patients and was significantly higher in those carrying PICC than CICC (p = 0.0001). There were fewer thrombotic events in the patients receiving i.v. LMWH prophylaxis than in those receiving i.v. UFH. The use of anticoagulants was safe and not associated with hemorrhages.


Assuntos
Bacteriemia/etiologia , Cateterismo Venoso Central/efeitos adversos , Fungemia/etiologia , Neoplasias Hematológicas/terapia , Trombose/etiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/uso terapêutico , Bacteriemia/epidemiologia , Bacteriemia/prevenção & controle , Feminino , Fibrinolíticos/uso terapêutico , Fungemia/epidemiologia , Fungemia/prevenção & controle , Neoplasias Hematológicas/complicações , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Trombocitopenia/complicações , Trombose/epidemiologia , Trombose/prevenção & controle
8.
Cancer Genet Cytogenet ; 130(1): 75-8, 2001 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-11672778

RESUMO

We report a t(8;12)(q12; p13) as the sole cytogenetic anomaly in a patient with a myelodysplastic syndrome (MDS). By means of FISH, we mapped the genomic region involved in the breakpoint (bkp) on both chromosomes. The 12p13 bkp mapped between markers WI-664 and WI-9218, immediately distal to the breakpoint cluster region frequently involved in hematological neoplasms targeted by y964C10. The 8q12 bkp (not yet investigated by FISH) was characterized and found to occur between markers WI-3263 and D8S524 within the region recognized by y874E10.


Assuntos
Cromossomos Humanos Par 12 , Cromossomos Humanos Par 8 , Síndromes Mielodisplásicas/genética , Translocação Genética , Idoso , Cromossomos Artificiais de Levedura , Humanos , Hibridização in Situ Fluorescente , Cariotipagem
9.
Leuk Lymphoma ; 41(1-2): 147-50, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11342366

RESUMO

Hyperhomocysteinemia (HH) has been associated with cardiovascular and autoimmune diseases and oxidative cell damage. Myelodysplastic syndromes (MDS) are associated with autoimmunity (AI) and increased oxidative stress. We tested the association of HH and oxidative stress in 33 MDS patients, by measuring plasma homocysteine and malondialdehyde (MDA). HH was found in 42% of cases, (4/5) cases with associated cardiovascular events (CVE)(80%), and 9/15 cases with associated AI (60%). Thus in MDS, HH was significantly associated with AI/CVE (chi(2) : p=0.0011), and this association seems to be specific, as demonstrated by the comparison of MDS presenting AI/CVE with the ischemic cardiopathy/rheumatoid arthritis control group (13/20, 65% vs 19/69, 27%; chi(2) : p=0.0021). The levels of MDA indicated increased oxidative stress. Our data may suggest that in a subset of MDS, HH may simultaneously contribute to bone marrow myelodysplasia, CVE and AI pathogenesis, possibly through oxidative cell damage.


Assuntos
Hiper-Homocisteinemia/complicações , Síndromes Mielodisplásicas/complicações , Análise de Variância , Autoimunidade/fisiologia , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/etiologia , Estudos de Casos e Controles , Jejum , Homocisteína/sangue , Humanos , Peroxidação de Lipídeos , Malondialdeído/sangue , Síndromes Mielodisplásicas/sangue , Síndromes Mielodisplásicas/imunologia , Estresse Oxidativo/fisiologia
10.
Br J Haematol ; 112(4): 969-71, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11298593

RESUMO

Campath-1H, an anti-CD52 monoclonal antibody, is therapeutically active in lymphoproliferative and autoimmune diseases. After Campath-1H therapy, lymphocytes with a paroxysmal nocturnal haemoglobinuria (PNH) phenotype have been reported to emerge. We characterized a PNH-like lymphocyte population emerging after Campath-1H therapy, in a patient with fludarabine refractory B-cell chronic lymphocytic leukaemia (B-CLL). We demonstrated a reduction in PIG-A mRNA levels compared with controls, and of all cytokines tested [interleukin (IL)-4, IL-13, IL-2, interferon(IFN)-gamma, IL-6, IL-10, and tumour necrosis factor (TNF)-alpha], except transforming growth factor (TGF)-beta. Given the inhibitory activity of TGF-beta, its elevated levels may contribute to the selective pressure of Campath-1H, leading to the emergence of PNH-like lymphocytes.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Anticorpos Antineoplásicos/administração & dosagem , Hemoglobinúria Paroxística/imunologia , Leucemia Linfocítica Crônica de Células B/imunologia , Leucemia Linfocítica Crônica de Células B/terapia , Linfócitos/imunologia , Alemtuzumab , Anticorpos Monoclonais Humanizados , Estudos de Casos e Controles , Citometria de Fluxo , Humanos , Interferon gama/metabolismo , Interleucina-10/metabolismo , Interleucina-13/metabolismo , Interleucina-2/metabolismo , Interleucina-4/metabolismo , Interleucina-6/metabolismo , Linfócitos/metabolismo , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Fito-Hemaglutininas/farmacologia , Polimorfismo Conformacional de Fita Simples , RNA Mensageiro/análise , Fator de Crescimento Transformador beta/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
11.
Anticancer Res ; 19(2A): 1043-51, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10368653

RESUMO

BACKGROUND: We investigated the role of apoptosis and its potential alterations in laryngeal squamous cell carcinomas (LSCCs) by evaluating bax, bcl-2 and p53 protein expression in 50 cases and by characterising the molecular status of the bax and p53 genes. MATERIAL AND METHODS: p53 and bax gene mutations were investigated by means of PCR/SSCP and direct DNA sequencing, and bax, bcl-2 and p53 protein expression by means of immunohistochemistry. RESULTS: We identified p53 gene mutations in 17/50 cases (34%); p53 expression in 26 of the 50 cases (52%); bcl-2 expression in 5/50 cases (10%); bax expression in 32/47 cases (68%). 18/33 cases with a wild type p53 gene overexpressed p53 protein: 12 cases (approximately 66%) were bax+/bcl-2-. Of the remaining cases without p53 protein expression, seven cases (approximately 47%) were bax+/bcl-2-. CONCLUSIONS: Our observations suggest that the overexpression of p53 may contribute to the repression of bcl-2 and the induction of bax expression in LSCCs. However, the fact that a number of cases not expressing p53 did not present any clear up-regulation of bax or down-regulation of bcl-2 suggests that bcl-2 and bax may be regulated by various mechanisms other than p53.


Assuntos
Carcinoma de Células Escamosas/genética , Genes bcl-2 , Genes p53 , Neoplasias Laríngeas/genética , Proteínas Proto-Oncogênicas/genética , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Mutação , Proteínas Proto-Oncogênicas/análise , Proteínas Proto-Oncogênicas c-bcl-2/análise , Proteína Supressora de Tumor p53/análise , Proteína X Associada a bcl-2
14.
Proc Natl Acad Sci U S A ; 95(20): 11816-21, 1998 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-9751748

RESUMO

The molecular mechanism involved in the process of antigen-driven somatic hypermutation of Ig genes is unknown, but it is commonly believed that this mechanism is restricted to the Ig loci. B cell lymphomas commonly display multiple somatic mutations clustering in the 5'-regulatory region of BCL-6, a proto-oncogene encoding for a POZ/Zinc finger transcriptional repressor expressed in germinal center (GC) B cells and required for GC formation. To determine whether BCL-6 mutations represent a tumor-associated phenomenon or reflect a physiologic mechanism, we screened single human tonsillar GC B cells for mutations occurring in the BCL-6 5'-noncoding region and in the Ig variable heavy chain sequences. Thirty percent of GC B cells, but not naive B cells, displayed mutations in the 742 bp region analyzed within the first intron of BCL-6 (overall frequency: 5 x 10(-4)/bp). Accordingly, an expanded survey in lymphoid malignancies showed that BCL-6 mutations are restricted to B cell tumors displaying GC or post-GC phenotype and carrying mutated Ig variable heavy chain sequences. These results indicate that the somatic hypermutation mechanism active in GC B cells physiologically targets non-Ig sequences.


Assuntos
Linfócitos B/imunologia , Linfócitos B/metabolismo , Proteínas de Ligação a DNA/genética , Genes de Imunoglobulinas , Mutação , Proteínas Proto-Oncogênicas/genética , Fatores de Transcrição/genética , Transformação Celular Neoplásica , Centro Germinativo/citologia , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Região Variável de Imunoglobulina/genética , Leucemia de Células B/genética , Leucemia de Células B/imunologia , Linfoma de Células B/genética , Linfoma de Células B/imunologia , Neoplasias/genética , Neoplasias/imunologia , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas c-bcl-6
15.
Br J Haematol ; 99(2): 375-8, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9375758

RESUMO

We have recently reported a series of 15 non-villous splenic marginal zone lymphoma patients, six of whom showed p53 mutations (40%). This molecular alteration did not correlate with any particular clinico-pathologic feature at diagnosis. After a median follow-up of 56 months, four cases evolved into aggressive fatal non-Hodgkin's lymphoma (NHL) and two had refractory progressive disease; interestingly, p53 mutations were demonstrated in five of these patients at diagnosis. As the patients with wild-type p53 presented responsive or indolent disease, this genetic alteration may be an early marker of aggressive transformation or refractoriness. p53 evaluation at diagnosis could be advisable in this particular subset of NHL.


Assuntos
Genes p53/genética , Linfoma não Hodgkin/genética , Mutação , Neoplasias Esplênicas/genética , Adolescente , Adulto , Idoso , Transformação Celular Neoplásica , Seguimentos , Humanos , Pessoa de Meia-Idade , Prognóstico
16.
J Heart Lung Transplant ; 16(9): 964-8, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9322148

RESUMO

Posttransplantation lymphoproliferative disorders (PTLDs) represent an important complication of solid organ transplantation. The main causative factor of PTLDs seems to be the intensity and type of immunosuppressive therapy and the frequent occurrence of Epstein-Barr virus infection. PTLDs that are disseminated at diagnosis or present late after transplantation generally share an unfavorable prognosis and are unlikely to regress in response to reduction in immunosuppressive therapy. We describe a case of cutaneous B-cell lymphoma occurring 4 years after heart transplantation in which molecular analysis revealed a monoclonal pattern of Epstein-Barr virus infection and immunoglobulin gene rearrangement. In spite of its monoclonal nature and late occurrence, the lymphomatous lesions regressed completely after antiviral treatment and a reduction in immunosuppressive therapy.


Assuntos
Aciclovir/administração & dosagem , Antivirais/administração & dosagem , Transplante de Coração/imunologia , Infecções por Herpesviridae/tratamento farmacológico , Herpesvirus Humano 4 , Imunossupressores/administração & dosagem , Linfoma de Células B/tratamento farmacológico , Infecções Oportunistas/tratamento farmacológico , Complicações Pós-Operatórias/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Infecções Tumorais por Vírus/tratamento farmacológico , Aciclovir/efeitos adversos , Antivirais/efeitos adversos , Relação Dose-Resposta a Droga , Esquema de Medicação , Quimioterapia Combinada , Infecções por Herpesviridae/imunologia , Humanos , Imunossupressores/efeitos adversos , Linfoma de Células B/imunologia , Masculino , Pessoa de Meia-Idade , Infecções Oportunistas/imunologia , Complicações Pós-Operatórias/imunologia , Prognóstico , Neoplasias Cutâneas/imunologia , Infecções Tumorais por Vírus/imunologia
17.
Genomics ; 42(3): 369-77, 1997 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-9205107

RESUMO

Frequent deletions and loss of heterozygosity in a segment of chromosome 13 (13q14) in cases of B-cell chronic lymphocytic leukemia (CLL) have suggested that this malignancy is caused by inactivation of an unknown tumor suppressor gene located in this region. Toward the identification of the putative CLL tumor suppressor, we have constructed a high-resolution physical map of YAC, PAC, and cosmid contigs covering 600 kb of the 13q14 genomic region. In addition to densely positioned genetic markers and STSs, this map was further annotated by localization of 32 transcribed sequences (ESTs) using a combination of exon trapping, direct cDNA selection, sample sequencing of cosmids and PACs, and homology searches. On the basis of these mapping data, allelic loss analyses at 13q14 using CLL tumor samples allowed narrowing of the genomic segment encompassing the putative CLL gene to <300 kb. Twenty-three ESTs located within this minimally deleted region are candidate exons for the CLL-associated tumor suppressor gene.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 13 , Leucemia Linfocítica Crônica de Células B/genética , Alelos , Animais , Sequência de Bases , Linhagem Celular , Mapeamento Cromossômico , Clonagem Molecular , Cricetinae , DNA , Humanos , Células Híbridas , Dados de Sequência Molecular , Transcrição Gênica
18.
Cancer ; 79(6): 1114-21, 1997 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-9070488

RESUMO

BACKGROUND: The molecular pathogenesis of laryngeal squamous cell carcinomas (LSCCs) is still only partially understood, although genetic alterations affecting various protooncogenes or tumor suppressor genes have often been detected. METHODS: To improve their understanding of the role of cyclin D1 in the pathogenesis of LSCCs, the authors investigated the expression of cyclin D1 protein and the amplification status of the bcl-1/cyclin D1 locus in a panel of 58 pathologic samples. RESULTS: Expression of cyclin D1 protein was detected in 23 of the 58 patients (approximately 39%), 14 of whom had lymph node metastases (approximately 61%); of the remaining 35 patients without any detectable cyclin D1 expression, 7 had lymph node metastases (20%). Expression of cyclin D1 was detectable in 5% of the specimens of normal mucosa, 13% of those with mild-to-moderate dysplasia, and 25% of those with severe dysplasia. Amplification of the bcl-1/cyclin D1 locus was detected in 12 of the 49 LSCCs investigated (approximately 24%), 7 of which had lymph node metastases (approximately 58%); of the remaining 37 LSCCs with an apparently normal copy number of the cyclin D1 locus, 12 had lymph node metastases (approximately 32%). The authors found almost complete concordance between locus amplification and protein expression. Statistical analysis showed a correlation between cyclin D1 expression and both the presence of lymph node metastases (P < 0.01) and advanced clinical stage (P < 0.02). CONCLUSIONS: The authors' observations suggest that the deregulation of cyclin D1 expression may be involved in the pathogenesis of more aggressive LSCCs.


Assuntos
Carcinoma de Células Escamosas/genética , Ciclinas/genética , Genes bcl-2 , Neoplasias Laríngeas/genética , Proteínas Oncogênicas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/patologia , Ciclina D1 , Ciclinas/isolamento & purificação , Feminino , Amplificação de Genes , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Laríngeas/patologia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Proteínas Oncogênicas/isolamento & purificação
19.
Oncogene ; 14(7): 791-9, 1997 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-9047386

RESUMO

Alterations of NF-kappaB family members have been found to be associated with various forms of lymphoid malignancies. In order to determine whether alterations of the RelA gene are involved in lymphomagenesis, we analysed a large and representative panel (200 cases) of such tumors. Southern blot analysis did not reveal any rearrangements or locus amplification, suggesting that structural alterations of the RelA gene may represent rare events in lymphoid neoplasia. By means of PCR-SSCP analysis, we were able to identify a single point mutation leading to amino acid substitution (codon 494, Glu-Asp) in the transactivating (TA) domain in one case of multiple myeloma. The mutated allele was expressed in the pathological bone marrow sample but not in the peripheral blood cells of the patient. We demonstrate that the RelA protein carrying this specific mutation (called RelA494D) has less transactivating ability than the normal RelA protein. Interestingly, the mutated protein has a lower affinity for kappaB binding sites both as a homodimer or in association with the NFKB1/p50 subunit. Transfection experiments using a Gal4-RelA494D fusion protein indicated that the mutation does not alter the intrinsic transactivating ability of the TA domain of RelA. Furthermore, in vitro translated RelA494D is able to dimerize efficiently with other NF-kappaB members, such as p50, cREL and Ikappa Balpha. Our data therefore suggest that this mutation may alter the specific structural conformation needed for the DNA interaction of RelA, and provide insights into the amino acid sequences involved in mediating the biological activities of RelA.


Assuntos
DNA/metabolismo , Proteínas I-kappa B , Mieloma Múltiplo/genética , NF-kappa B/genética , Mutação Puntual , Transativadores/farmacologia , Animais , Células COS , Transformação Celular Neoplásica , Citoplasma/química , Proteínas de Ligação a DNA/fisiologia , Células HeLa , Humanos , Inibidor de NF-kappaB alfa , NF-kappa B/metabolismo , NF-kappa B/farmacologia , Fator de Transcrição RelA
20.
Haematologica ; 82(1): 16-20, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9107076

RESUMO

BACKGROUND AND OBJECTIVE: Bcl-2 oncogenic protein expression plays a major role in blocking the apoptotic mechanism. p53 gene mutations have also been suggested to account for the chlorambucil resistance in CLL. Thus we studied the relationship between bcl-2 protein expression, p53 gene mutations and in vitro drug sensitivity in CLL. METHODS: Fifty-three samples from untreated CLL patients in early disease stages were tested in vitro for chemosensitivity to chlorambucil (CLB), fludarabine (FAMP) and 2-chlorodeoxyadenosine (2-CDA) using the MTT assay. Intracellular bcl-2 protein expression was evaluated by flow cytometry analysis. p53 gene mutations were detected by using polymerase chain reaction (PCR)-single strand conformation polymorphism (SSCP) analysis. RESULTS: The median LD50 values were 1.55 microM, 4.41 microM and 58.2 microM for 2-CDA, FAMP and CLB, respectively. About 23%, 41% and 11% of samples were defined as being sensitive to FAMP, 2-CDA and CLB, respectively, when samples were clustered for LD50 threshold values corresponding to the plasmatic levels of the drug. No statistically significant difference in bcl-2 protein expression was noted between sensitive and resistant samples for each drug. A p53 gene mutation was detected in 4 of the 30 cases studies and all of them were among samples resistant to CLB. INTERPRETATION AND CONCLUSIONS: Bcl-2 expression is not an indicator of in vitro response to drugs in CLL; similarly, although the four cases showing a p53 gene mutation were associated with CLB resistance, drug resistant samples were also observed in the group of patients showing wild type p53, suggesting multiple mechanisms of drug resistance in CLL.


Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Antineoplásicos Alquilantes/farmacologia , Clorambucila/farmacologia , Cladribina/farmacologia , Genes p53 , Leucemia Linfocítica Crônica de Células B/patologia , Proteínas de Neoplasias/biossíntese , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Vidarabina/análogos & derivados , Sobrevivência Celular/efeitos dos fármacos , DNA de Neoplasias/análise , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Leucemia Linfocítica Crônica de Células B/genética , Proteínas de Neoplasias/genética , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Proteínas Proto-Oncogênicas c-bcl-2/genética , Células Tumorais Cultivadas/efeitos dos fármacos , Vidarabina/farmacologia
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