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1.
Am J Hematol ; 99(4): 745-750, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38264829

RESUMO

Profound immune dysregulation and impaired response to the SARS-CoV-2 vaccine put patients with chronic lymphocytic leukemia (CLL) at risk of severe COVID-19. We compared humoral memory and T-cell responses after booster dose vaccination or breakthrough infection. (Green) Quantitative determination of anti-Spike specific antibodies. Booster doses increased seroconversion rate and antibody titers in all patient categories, ultimately generating humoral responses similar to those observed in the postinfection cohort. In detail, humoral response with overscale median antibody titers arose in >80% of patients in watch and wait, off-therapy in remission, or under treatment with venetoclax single-agent. Anti-CD20 antibodies and active treatment with BTK inhibitors (BTKi) represent limiting factors of humoral response, still memory mounted in ~40% of cases following booster doses or infection. (Blue) Evaluation of SARS-CoV-2-specific T-cell responses. Number of T-cell functional activation markers documented in each patient. The vast majority of patients, including those seronegative, developed T-cell responses, qualitatively similar between treatment groups or between vaccination alone and infection cases. These data highlight the efficacy of booster doses in eliciting T-cell immunity independently of treatment status and support the use of additional vaccination boosters to stimulate humoral immunity in patients on active CLL-directed treatments.


Assuntos
COVID-19 , Leucemia Linfocítica Crônica de Células B , Humanos , SARS-CoV-2 , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Vacinas contra COVID-19 , Anticorpos , Subunidade alfa de Receptor de Interleucina-2 , Imunidade Celular , Anticorpos Antivirais , Vacinação
2.
Leukemia ; 23(5): 919-24, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19148139

RESUMO

The chronic lymphocytic leukemia (CLL) immunoglobulin repertoire is uniquely characterized by the presence of stereotyped B-cell receptors (BCRs). A major BCR stereotype in CLL is shared by immunoglobulin G-switched cases utilizing the immunoglobulin heavy-chain variable 4-34 (IGHV4-34) gene. Increased titers of IGHV4-34 antibodies are detected in selective clinical conditions, including infection by B-cell lymphotropic viruses, particularly Epstein-Barr virus (EBV) and cytomegalovirus (CMV). In this context, we sought evidence for persistent activation by EBV and CMV in CLL cases expressing the IGHV4-34 gene. The study group included 93 CLL cases with an intentional bias for the IGHV4-34 gene. On the basis of real-time PCR results for CMV/EBV DNA, cases were assigned to three groups: (1) double-negative (59/93); (2) single-positive (CMV- or EBV-positive; 25/93); (3) double-positive (9/93). The double-negative group was characterized by heterogeneous IGHV gene repertoire. In contrast, a bias for the IGHV4-34 gene was observed in the single-positive group (9/25 cases; 36%). Remarkably, all nine double-positive cases utilized the IGHV4-34 gene; seven of nine cases expressed the major BCR stereotype as described above. In conclusion, our findings indicate that the interactions of CLL progenitor cells expressing distinctive IGHV4-34 BCRs with viral antigens/superantigens might facilitate clonal expansion and, eventually, leukemic transformation. The exact type, timing and location of these interactions remain to be determined.


Assuntos
Citomegalovirus/fisiologia , Herpesvirus Humano 4/fisiologia , Cadeias Pesadas de Imunoglobulinas/genética , Região Variável de Imunoglobulina/genética , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/virologia , Receptores de Antígenos de Linfócitos B/genética , Idoso , Linfócitos B/imunologia , Linfócitos B/patologia , Estudos de Casos e Controles , Estudos de Coortes , Progressão da Doença , Feminino , Genoma Viral , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Hipermutação Somática de Imunoglobulina , Fatores de Tempo , Ativação Viral
5.
Br J Cancer ; 88(8): 1168-74, 2003 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-12698179

RESUMO

Given the established individual activity of docetaxel and ifosfamide in anthracycline pretreated advanced breast cancer, the present phase I-II study aimed to define the maximum tolerated dose (MTD), the dose-limiting toxicities (DLTs), and activity of the docetaxel-ifosfamide combination in this setting. Cohorts of three to six patients with histologically confirmed metastatic breast cancer after prior anthracycline-based chemotherapy were treated at successive dose levels (DLs) with escalated doses of docetaxel 70-100 mg x m(-2) over 1 h on day 1 followed by ifosfamide 5-6 g x m(-2) divided over days 1 and 2 (2.5-3.0 g x m(-2) day(-1) over 1 h), and recycled every 21 days. G-CSF was added once dose-limiting neutropenia was encountered at a certain DL and planned to be incorporated prophylactically in subsequent higher DLs. In total, 56 patients with a median age of 54.5 (range, 32-72) years and performance status (WHO) of 1 (range, 0-2) were treated at five DLs as follows: 21 in phase I DLs (DL1: 3, DL2: 6, DL3: 3, DL4: 6, and DL5: 3) and the remaining 35 were treated at DL4 (total of 41 patients at DL4), which was defined as the level for phase II testing. All patients were assessable for toxicity and 53 for response. Dose-limiting toxicity (with the addition of G-CSF after DL2) was reached at DL5 with two out of three initial patients developing febrile neutropenia (FN). Clinical response rates, on an intention-to-treat basis, in phase II were: 53.6% (95% CI, 38.3-68.9%); three complete remissions, 19 partial remissions, seven stable disease, and 12 progressive disease. The median response duration was 7 months (3-24 months), median time to progression 6.5 month (0.1-26 month), and median overall survival 13 months (0.1-33 months). Grade 3/4 toxicities included time to progression neutropenia in 78% of patients-with 63% developing grade 4 neutropenia (

Assuntos
Antraciclinas/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/toxicidade , Neoplasias da Mama/tratamento farmacológico , Ifosfamida/toxicidade , Taxoides/toxicidade , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Docetaxel , Relação Dose-Resposta a Droga , Feminino , Humanos , Ifosfamida/administração & dosagem , Ifosfamida/uso terapêutico , Infusões Intravenosas , Pessoa de Meia-Idade , Análise de Sobrevida , Taxoides/administração & dosagem , Taxoides/uso terapêutico , Falha de Tratamento
6.
Leukemia ; 16(10): 2004-15, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12357351

RESUMO

Over the last 5 years, studies applying the chimeric anti-CD20 MAb have renewed enthusiasm and triggered world-wide application of anti-CD20 MAb-based therapies in B cell non-Hodgkin's lymphoma (NHL). Native chimeric anti-CD20 and isotope-labeled murine anti-CD20 MAbs are currently employed with encouraging results as monotherapy or in combination with conventional chemotherapy and in consolidation of remission after treatments with curative intent (ie after/ in combination with high-dose chemotherapy and hematopoietic stem cell rescue). On the available experience, anti-CD20 MAb-based therapeutic strategies will be increasingly integrated in the treatment of B cell NHL and related malignancies.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antígenos CD20/imunologia , Linfoma de Células B/terapia , Antineoplásicos/uso terapêutico , Terapia Combinada , Humanos , Linfoma de Células B/tratamento farmacológico
7.
Leuk Res ; 26(6): 597-600, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12007508

RESUMO

We report two cases with B cell malignancies (case #1: refractory mantle cell lymphoma; case #2: lymphocyte predominant Hodgkin's disease (LPHD)) who developed neutropenia post-Rituximab therapy in a setting of significant infiltration of the peripheral blood (PB) and bone marrow (BM) by T cells with an immunophenotype of large granular lymphocytes. Possible pathogenetic mechanisms are discussed.


Assuntos
Anticorpos Monoclonais/efeitos adversos , Antineoplásicos/efeitos adversos , Linfoma de Células B/tratamento farmacológico , Neutropenia/induzido quimicamente , Linfócitos T/patologia , Adulto , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais Murinos , Antígenos CD/análise , Antineoplásicos/administração & dosagem , Humanos , Imunofenotipagem , Linfoma de Células B/complicações , Masculino , Neutropenia/etiologia , Rituximab , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia
8.
Cancer ; 92(11): 2902-10, 2001 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11753965

RESUMO

BACKGROUND: Treatment options for patients with recurrent nonsmall cell lung carcinoma (NSCLC) remain limited as a result of poor activity of older agents after platinum-based therapy. In the current Phase II study, the authors evaluated the combination of gemcitabine and docetaxel in patients with recurrent NSCLC. METHODS: Patients with advanced NSCLC (Stage IIIB-IV), a World Health Organization performance status (PS) < or = 2, prior paclitaxel plus platinum-based chemotherapy, and unimpaired hematopoietic and organ function were eligible. Chemotherapy was administered as follows: gemcitabine 1000 mg/m(2) was administered on Days 1 and 8 followed by docetaxel 100 mg/m(2) on Day 8, and this regimen was recycled every 21 days. Prophylactic granulocyte-colony stimulating factor was administered on Days 10-14 or until the patient achieved a white blood cell count > or = 5000/microL. RESULTS: Of 43 patients who were entered on the study, 41 patients were evaluable for response, and all were evaluable for toxicity. The median patient age was 63 years (range, 47-70 years), the median PS was 1 (range, 0-2), there were 38 male patients, and there were 5 female patients. Four patients had Stage IIIA disease, 17 patients had Stage IIIB disease, and 22 patients had Stage IV disease. Histologies included 19 patients with adenocarcinoma, 18 patients with squamous cell carcinoma, and 3 patients with large cell carcinoma. Metastatic sites included lymph nodes in 28 patients, bone in 6 patients, liver in 5 patients, brain in 5 patients, lung nodules in 8 patients, adrenals in 7 patients, and other sites in 3 patients. All patients had received prior paclitaxel plus platinum-based treatment; 28 patients had received prior paclitaxel, ifosfamide, and cisplatin. Objective responses were partial response (PR) in 14 of 43 patients [33%; 95% confidence interval [95%CI], 18.5-46.6%], stable disease (SD) in 16 of 43 patients (37%; 95% CI, 22.8-51.6%), and progressive disease (PD) in 13 of 43 patients (30%; 95% CI, 16.3-43.7%). The median time to disease progression was 6 months (range, 1.0-20.0+ months), and the median survival was 8.5 months (range, 1.5-20.0+ months). The 1-year survival rate was 28%. Grade 3-4 neutropenia was experienced by 53% of patients (30% Grade 4), with 14% of patients experiencing febrile neutropenia. Grade 3 thrombocytopenia was experienced by 7% of patients (no Grade 4), whereas other Grade 3 nonhematologic toxicities were never encountered. CONCLUSIONS: The combination of gemcitabine and docetaxel is active and is well tolerated in patients with advanced NSCLC who have failed prior taxane plus platinum chemotherapy. This regimen represents a tolerable and effective combination to apply in the palliative treatment of patients with recurrent NSCLC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Desoxicitidina/análogos & derivados , Neoplasias Pulmonares/tratamento farmacológico , Paclitaxel/análogos & derivados , Taxoides , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Docetaxel , Feminino , Humanos , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Paclitaxel/administração & dosagem , Paclitaxel/efeitos adversos , Paclitaxel/uso terapêutico , Cooperação do Paciente , Platina/uso terapêutico , Análise de Sobrevida , Resultado do Tratamento , Gencitabina
9.
Br J Haematol ; 115(1): 19-24, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11722405

RESUMO

Transferrin receptor (TfR, CD71) is an integral membrane glycoprotein that mediates cellular uptake of iron. In most tissues, TfR expression is correlated positively with proliferation and regulated at the post-transcriptional level. The available data regarding the pattern of TfR gene expression in haematological malignancies are very limited. In the present study, we evaluated TfR gene expression at the molecular level in bone marrow (BM) samples of 44 patients with de novo acute myeloid leukaemia (AML) at diagnosis with BM blasts > 85%. TfR mRNA levels were determined by densitometric analysis of quantitative reverse transcription polymerase chain reaction products corresponding to TfR exons 15-17. Each sample was tested in at least two independent experiments. In 13/44 patients, TfR messages were not detected (this is probably an underestimate as some positive results may be attributed to residual normal erythroid cells present in the samples). In 17/44, TfR mRNA levels were low-intermediate, and were high in the remaining patients (14/44). TfR mRNA positivity was significantly associated with older age. No statistically significant correlations were found either with specific French-American-British (FAB) subtypes or attainment of complete remission, incidence of relapse and survival (after adjusting accordingly for age and FAB subtype). The absence of TfR mRNA transcripts in a significant minority of cases suggests that alternative mechanisms of iron uptake may function in AML blast cells.


Assuntos
Medula Óssea/metabolismo , Leucemia Mieloide/metabolismo , RNA Mensageiro/genética , Receptores da Transferrina/genética , Doença Aguda , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Fragmentos Fab das Imunoglobulinas/análise , Cariotipagem , Leucemia Mieloide/imunologia , Leucemia Mieloide/terapia , Masculino , Pessoa de Meia-Idade , Indução de Remissão , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sobrevida
11.
Leukemia ; 15(11): 1772-8, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11681420

RESUMO

In this study, we analyzed the targeting of the somatic hypermutation (SHM) mechanism at specific hotspot sequence motifs in the V(H) and Vkappa genes of 10 follicular lymphoma (FL) cases and the Vkappa and Vlambda genes of 11 kappa- and six lamda-light chain expressing multiple myeloma (MM) cases. These sequences were analyzed for targeting of specific motifs, ie certain highly mutable trinucleotides (3-NTPs), the tetranucleotide (4-NTP) RGYW and its complementary, WRCY (where R = purine, Y = pyrimidine and W = A or T). Comparisons were carried out between mutation frequencies in RGYW vs WRCY and the incidence of mutations in complementarity determining region (CDR)-1 vs CDR2 vs CDR3. Statistically significant differences were obtained when comparing: (1) the ratio of mutations in 4-NTPs (RGYW, WRCY, RGYW+WRCY)/mutations in the whole V sequence in MM-Vkappa vs MM-Vlamda; (2) the total number of mutated 4-NTPs in MM-Vkappa vs FL-Vkappa; (3) the number of mutated RGYW 4-NTPs in MM-Vkappa vs FL-Vkappa and FL-V(H) vs FL-Vkappa; (4) the number of mutated WRCY 4-NTPs in MM-Vkappa vs FL-Vkappa (P= 0.006) and FL-V(H) vs FL-Vkappa; (5) the targeting of RGYW vs WRCY in the CDRs of FL-V(H) genes. Similar results (regarding statistical significance) were obtained when undertaking intergroup comparisons for 3-NTPs. These findings conform well with relevant data derived from normal peripheral B cells. The differences observed in favor of 4-NTP (RGYW and WRCY) targeting in FL-V(H) vs FL-Vkappa and MM-Vkappa vs FL-Vkappa may implicate differences in the evolution of SHM coupled with selection in different stages of B cell ontogeny. Several explanations can be offered for the fact that hotspot sequences were not always targeted by SHM in FL and MM: (1) other unrecognized motifs may be targets of SHM; (2) 'inappropriately' introduced mutations were fixed and propagated by the neoplastic process; (3) certain FL and MM cases might have lost their ability to correct mutations introduced in classic hotspots due to deficient mismatch-repair (MMR) mechanisms; conversely, in other cases with intact MMR function, the hotspot to non-hotspot targeting of somatic hypermutation is balanced.


Assuntos
Regiões Determinantes de Complementaridade/genética , Genes de Imunoglobulinas , Linfoma Folicular/genética , Mieloma Múltiplo/genética , Mutação , Sequência de Bases , Análise Mutacional de DNA , DNA de Neoplasias/análise , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias Leves de Imunoglobulina/genética , Dados de Sequência Molecular
12.
Eur J Cancer ; 37(8): 972-8, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11334721

RESUMO

Treatment options in patients with recurrent non-small-cell lung cancer (NSCLC) remain limited as a result of the poor activity of older agents after platinum-based therapy. The present phase II study aimed to evaluate the combination of gemcitabine and vinorelbine in patients with relapsed NSCLC after pretreatment with taxane+platinum-based regimens, since gemcitabine has demonstrated activity in that setting and the combination has been well tolerated in previous phase I/II studies. Patients with advanced NSCLC (stages III/IV), World Health Organization (WHO), Performance Status (PS) < or = 2, prior platinum+taxane-based chemotherapy and unimpaired haematopoietic and organ function were eligible. Chemotherapy was administered as follows: vinorelbine 25 mg/m(2) followed by gemcitabine 1000 mg/m(2), both administered on days 1 and 8, recycled every 3 weeks. 40 patients were entered and 39 were evaluable for response and all 40 for toxicity: median age was 61 years (range 50-72 years), median PS=1 (range 0-2), gender ratio=37 males/3 females, stages at initial diagnoses were IIIA=2, IIIB=14, IV=24. Metastatic sites included: lymph nodes: 23, bone: 4, liver: 5, brain: 4, lung nodules: 9, adrenals: 8, pleural effusion: 4. 22 patients had prior paclitaxel/ifosfamide/cisplatin treatment. Objective responses were; partial response (PR): 9/40 (22.5%), stable disease (SD): 13/40 (32.5%) and progressive disease (PD) 18/40 (45%). The median time-to-progression (TTP) was 4.5 months (range 1-17 months) and median survival 7 months (range 2-17+ months). 1-year survival was 17%. Grade 3 neutropenia was seen in 33% of patients. There was no grade 4 neutropenia and no episodes of febrile neutropenia. No grade 3/4 thrombocytopenia or grade 3/4 other non-haematological toxicities were observed. The combination of gemcitabine/vinorelbine is active and well tolerated in patients with advanced NSCLC failing prior taxane/platinum therapy. This regimen represents a tolerable and effective combination to apply in the palliative treatment of relapsed NSCLC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Vimblastina/análogos & derivados , Adulto , Idoso , Cisplatino/administração & dosagem , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Desoxicitidina/análogos & derivados , Feminino , Humanos , Ifosfamida/administração & dosagem , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Paclitaxel/administração & dosagem , Cooperação do Paciente , Análise de Sobrevida , Resultado do Tratamento , Vimblastina/administração & dosagem , Vimblastina/efeitos adversos , Vinorelbina , Gencitabina
13.
Leukemia ; 14(10): 1718-26, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11021746

RESUMO

The study of immunoglobulin genes in multiple myeloma over the last decade has provided important information regarding biology, ontogenetic assignment, disease evolution, pathogenic consequences and tumor-specific therapeutic intervention. Detailed analysis of VH genes has revealed the clonal relationship between switch variants expressed by the bone marrow plasma cell and myeloma progenitors in the marrow and peripheral blood. Regarding VH usage, a bias was found against the V4-34 gene encoding antibodies with cold agglutinin specificity (anti-I/i), thus explaining in part the absence of autoimmune phenomena in myeloma compared to other B cell lymphoproliferative disorders. However, in some studies a substantial number of cases analyzed were carrying the rearranged Humkappav325 Vkapppa gene, known to be over utilized by B cell chronic lymphocytic leukemia clones and possessing autoantibody binding activity. VH genes accumulate somatic hypermutations following a distribution compatible with antigen selection, but with no intraclonal heterogeneity. The analysis of Vkappa genes indicates a bias in usage of Vkappa family members; somatic hypermutation, in line with antigen selection, of the expressed Vkappa genes is higher than any other B cell lymphoid disorder. Similar conclusions were reached for Vlambda genes; in this case, the analysis raises the controversial issue of N nucleotide insertion at Vlambda-Jlambda junctions, apparently as a result of TdT activity. A complementary imprint of antigen selection as evidenced by somatic hypermutation of either the VH or VL clonogenic genes has been observed. The absence of ongoing somatic mutations in either VH or VL genes gives rise to the notion that the cell of origin in myeloma is a post-germinal center memory B cell.


Assuntos
Genes de Imunoglobulinas , Mieloma Múltiplo/imunologia , Antígenos de Neoplasias/imunologia , Vacinas Anticâncer/imunologia , Vacinas Anticâncer/uso terapêutico , Humanos , Mieloma Múltiplo/patologia
14.
Immunol Today ; 21(6): 298-305, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10825742

RESUMO

Follicular lymphoma is caused by the transformation of a germinal-center-derived B cell with a t(14;18) chromosomal translocation. The distribution of somatic mutations within immunoglobulin genes indicates that follicular-lymphoma cells can interact with antigen. In addition, nonimmunoglobulin genes such as BCL6 seem to undergo somatic hypermutation. Here, Kostas Stamatopoulos and colleagues relate the molecular data about immunoglobulin genes and the protooncogenes BCL2 and BCL6 to the pathogenesis and evolution of follicular lymphoma.


Assuntos
Genes de Imunoglobulinas , Linfoma Folicular/etiologia , Subpopulações de Linfócitos B/imunologia , Subpopulações de Linfócitos B/patologia , Cromossomos Humanos Par 14/genética , Cromossomos Humanos Par 18/genética , Deleção Clonal , DNA Nucleotidiltransferases/metabolismo , Células-Tronco de Carcinoma Embrionário , Rearranjo Gênico do Linfócito B , Centro Germinativo/patologia , Hematopoese/genética , Doença de Hodgkin/patologia , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Região Variável de Imunoglobulina/genética , Cadeias kappa de Imunoglobulina/genética , Linfoma Folicular/genética , Linfoma Folicular/imunologia , Linfoma Folicular/patologia , Modelos Imunológicos , Mutação , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/imunologia , Células-Tronco Neoplásicas/imunologia , Células-Tronco Neoplásicas/patologia , Células de Reed-Sternberg/patologia , Translocação Genética , VDJ Recombinases
15.
Cancer Genet Cytogenet ; 117(1): 82-3, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10700873

RESUMO

Acute promyelocytic leukemia was diagnosed in a 48-year-old man; the karyotype was normal, whereas reverse transcriptase polymerase chain reaction (RT-PCR) analysis identified PML/RAR alpha chimeric transcripts of the bcr3 type. Rather unexpectedly, the patient did not respond to alltrans retinoic acid administration; he attained complete remission with conventional chemotherapy and became PML/RAR alpha negative. Two years later, while PML/RAR alpha negative on RT-PCR, he presented with thrombocytopenia. Bone marrow examination was compatible with myelodysplasia of the RAEB type; the karyotype was normal. Then, after 10 months, he developed overt acute myeloid leukemia with PML/RAR alpha negative, French-American-British M2 blasts; karyotypic analysis revealed mosaicism for trisomy 8.


Assuntos
Cromossomos Humanos Par 8 , Leucemia Mieloide Aguda/genética , Leucemia Promielocítica Aguda/patologia , Trissomia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Recidiva , Reação em Cadeia da Polimerase Via Transcriptase Reversa
17.
Leuk Lymphoma ; 33(3-4): 253-65, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10221505

RESUMO

The study of immunoglobulin genes in multiple myeloma over the last five years has provided important information regarding biology, ontogenetic location, disease evolution, pathogenic consequences and tumor-specific therapeutic intervention with idiotypic vaccination. Detailed analysis of V(H) genes has revealed clonal relationship between switch variants expressed by the bone marrow plasma cell and myeloma progenitors in the marrow and peripheral blood. V(H) gene usage is biased against V4-34 (encoding antibodies with cold agglutinin specificity; anti-l/i) explaining the absence of autoimmune phenomena in myeloma compared to other B-cell lymphoproliferative disorders. V(H) genes accumulate somatic hypermutations following a distribution compatible with antigen selection, but with no intraclonal heterogeneity. V(L) genes indicate a bias in usage of VkappaI family members and somatic hypermutation, in line with antigen selection, of the expressed Vkappa genes is higher than any other B-cell lymphoid disorder. A complementary imprint of antigen selection as evidenced by somatic hypermutation of either the V(H) or V(L) clonogenic genes has been observed. The absence of ongoing somatic mutations in either V(H) or V(L) genes gives rise to the notion that the cell of origin in myeloma is a post-germinal center memory B-cell. Clinical application of sensitive PCR methods in order to detect clonal immunoglobulin gene rearrangements has made relevant the monitoring and follow-up of minimal residual disease in stem cell autografts and after myeloablative therapy. The fact that surface immunoglobulin V(H) and V(L) sequences constitute unique tumor-specific antigenic determinants has stimulated investigators to devise strategies aiming to generate active specific immunity against the idiotype of malignant B-cells in myeloma by constructing vaccines based on expressed single-chain Fv fragments, DNA plasmids carrying V(H)+V(L) clonogenic genes for naked DNA vaccination, or dendritic cell-based vaccination armed with the tumor-specific idiotype.


Assuntos
Genes de Imunoglobulinas , Mieloma Múltiplo/genética , Mieloma Múltiplo/imunologia , Linfócitos B/imunologia , Rearranjo Gênico , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias Leves de Imunoglobulina/genética , Região Variável de Imunoglobulina/genética , Transtornos Linfoproliferativos/genética , Transtornos Linfoproliferativos/imunologia
18.
Leukemia ; 13(4): 601-4, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10214868

RESUMO

Assembly of immunoglobulin (Ig) heavy (H) variable (V), diversity (D) and joining (J) gene segments constitutes an important determinant of commitment to the B cell lineage. The randomly selected D gene segment of a given VDJ complex can potentially be found in all three possible reading frames (RFs). In the present study, we examined the distribution of D gene RF in 'immature' and 'mature' B cell lymphoproliferative disorders (BCLD). We analyzed the clonotypic VDJ junctional sequences of our previously reported cases of follicular lymphoma (FL), as well as bcl-2/IgH junctions with recognized D elements. A marked under-representation of RF1 was observed, with almost equal usage of RF2 and RF3. A literature search for VDJ published sequences in various BCLD identified a similar pattern of D gene RF usage in multiple myeloma (MM), with marked predilection for RFs 2 and 3. In B cell chronic lymphocytic leukemia (B-CLL), the pattern of D-RF was 25% for RF1, 46% for RF2 and 29% for RF3, while in B cell precursor acute lymphoblastic leukemia (precursor-B-ALL) all three RFs were used with similar frequencies. The marked under-representation of RF1 in FL and MM clonogenic rearranged D genes suggests selection on the basis of antigenic properties, possibly due to constraints in forming a flexible loop within CDR3. In contrast, the more even distribution of D-RF usage in B-CLL and precursor-B-ALL suggests that, for these disorders, transformation of a immature type B cell repertoire has occurred.


Assuntos
Diversidade de Anticorpos , Linfócitos B/imunologia , Rearranjo Gênico de Cadeia Pesada de Linfócito B , Genes de Imunoglobulinas , Fragmentos de Imunoglobulinas/genética , Cadeias Pesadas de Imunoglobulinas/genética , Transtornos Linfoproliferativos/genética , Proteínas de Neoplasias/genética , Fases de Leitura Aberta , DNA Nucleotidiltransferases/metabolismo , Humanos , Leucemia/genética , Leucemia/imunologia , Linfoma/genética , Linfoma/imunologia , Transtornos Linfoproliferativos/imunologia , Proteínas de Neoplasias/metabolismo , VDJ Recombinases
19.
Br J Haematol ; 97(1): 135-6, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9136954

RESUMO

Trisomy 8 is the most common numerical chromosomal abnormality in myelodysplastic syndromes (MDS). Paroxysmal nocturnal haemoglobinuria (PNH) is an aquired haemolytic anaemia, clonal in nature, due to somatic mutation. PNH may evolve to aplastic anaemia, to MDS or to acute myeloid leukaemia. We present a patient who had trisomy 8 mosaicism at disease presentation who received therapy with all-trans-retinoic acid, responded to therapy, and developed PNH in the course of the disease. Cytogenetics at the time of PNH diagnosis showed a normal karyotype.


Assuntos
Cromossomos Humanos Par 8 , Hemoglobinúria Paroxística/complicações , Tretinoína/uso terapêutico , Trissomia , Adolescente , Feminino , Humanos , Mosaicismo , Síndromes Mielodisplásicas/complicações
20.
Leukemia ; 10(9): 1551-6, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8751479

RESUMO

Immunoglobulin heavy chain variable (V) gene replacement is an unusual recombinatorial event characterized by rearrangement of a germline V gene to a preformed VDJ gene complex. This phenomenon has occasionally been implicated in the emergence of clonal subpopulations during the course of acute lymphoblastic leukemia; it has also been found in murine precursor B cell lines. V gene replacement has never been described in lymphoproliferative disorders corresponding to more differentiated stages of B cell ontogeny. The present communication provides evidence for the operation of the same mechanism in B cell chronic lymphocytic leukemia (B-CLL). Genomic DNA and total cellular RNA extracted from peripheral blood mononuclear cells of a 48-year-old female patient diagnosed as having typical B-CLL were subjected to polymerase chain reaction (PCR) amplification aiming to detect rearranged clonal heavy and light chain variable genes (VH and VL, respectively). PCR consistently gave two VH amplification products, both at the DNA and the RNA level; similar analysis for the VL region revealed the presence of a single rearranged VK gene. Direct sequence analysis of the PCR products revealed that, except for a number of silent mutations, the single rearranged VK gene was identical to the germline A1-A17 VK gene. The two rearranged VH gene segments belong to the VHl and VHIII gene families and are closely homologous, respectively, to the germline gene segments V1-18 and V3-30, which have been shown to be used by autoantibodies. Both rearranged VH genes showed identical in-frame D-N-JH junctions and JH gene usage (JH5b), whereas the VH-N-D junctions were different. The above findings indicate that, during the course of the disease of our patient, VH gene replacement took place giving rise to two different clonally related subpopulations. This raises the intriguing possibility that the recombinase machinery, which governs Ig recombinatorial processes, might be operative even at more advanced stages in B cell ontogeny.


Assuntos
Rearranjo Gênico , Genes de Imunoglobulinas , Região Variável de Imunoglobulina/genética , Leucemia Linfocítica Crônica de Células B/genética , Sequência de Aminoácidos , Sequência de Bases , DNA de Neoplasias/genética , DNA de Neoplasias/metabolismo , Feminino , Humanos , Leucemia Linfocítica Crônica de Células B/metabolismo , Pessoa de Meia-Idade , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , RNA Neoplásico/genética , RNA Neoplásico/metabolismo
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