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Mucormycosis has emerged as an important cause of invasive fungal infection in patients with hematologic malignancies. Gastrointestinal mucormycosis is an unusual presentation of this invasive fungal infection, and it causes considerable morbidity and mortality. Such outcomes are due in part to a nonspecific presentation that results in delays in diagnosis and treatment. Successful treatment of gastrointestinal mucormycosis involves surgical debridement and appropriate antifungal therapy.
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BACKGROUND: Venous thromboembolism (vte) is a recognized complication in patients treated with asparaginase-containing chemotherapy regimens; the optimal preventive strategy is unclear. We assessed the safety and efficacy of prophylaxis using low-dose low molecular weight heparin in adult patients with acute lymphoblastic leukemia in complete remission treated with an asparaginase-based post-remission chemotherapy regimen. METHODS: As part of the intensification phase of the Dana-Farber Cancer Institute 91-01 regimen, asparaginase was administered weekly to 41 consecutive patients for 21-30 weeks; these patients also received prophylaxis with enoxaparin 40 mg daily (60 mg for patients ≥80 kg). Outcomes were assessed against outcomes in a comparable cohort of 99 patients who received the same chemotherapy regimen without anticoagulation prophylaxis. RESULTS: The overall rate of symptomatic venous thrombosis was not significantly different in the prophylaxis and non-prophylaxis cohorts (18.92% and 21.74% respectively). Among patients receiving prophylaxis, vte occurred in higher proportion in those who weighed at least 80 kg (42.86% vs. 4.35%, p = 0.0070). No major bleeding complications occurred in the prophylaxis group (minor bleeding: 8.1%). CONCLUSIONS: Prophylaxis with low-dose enoxaparin during the intensification phase was safe, but was not associated with a lower overall proportion of vte.
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BACKGROUND: Intensive chemotherapy (IC) used to treat acute myeloid leukemia (AML) is associated with toxicity, particularly in older adults. Emerging data suggest that baseline quality of life (QOL) and physical function may predict outcomes in oncology, although data in AML are limited. We investigated the association between baseline QOL and physical function with short-term treatment outcomes in adults and elderly AML patients. MATERIALS AND METHODS: We conducted a prospective, longitudinal study of adults (age 18+) AML patients undergoing IC. Before starting IC, patients completed the European Organisation for the Research and Treatment of Cancer (EORTC) 30-item questionnaire (QLQ-C30) and Functional Assessment of Cancer Therapy Fatigue subscale (FACT-Fatigue) in addition to physical function tests (grip strength, timed chair stands, 2-min walk test). Outcomes included 60-day mortality, intensive care unit (ICU) admission and achievement of complete remission (CR). Logistic regression was carried out to evaluate each outcome. RESULTS: Of the 239 patients (median age 57.5 years), 56.7% were male and median Charlson comorbidity score was 0. Sixty-day mortality, ICU admission and CR occurred in 9 (3.7%), 15 (6.3%) and 167 (69.9%) patients, respectively. Using univariate regression, neither QOL nor physical function at presentation was predictive of 60-day mortality (all P > 0.05), whereas ICU admission (P < 0.001) and remission status at 30 days (P = 0.007) were. Fatigue (P = 0.004) and role functioning (P = 0.003) were predictors of ICU admission; QOL and physical function were not. A higher Charlson score predicted ICU admission (P = 0.01) and remission status (P = 0.002). The cytogenetic risk group was associated with achievement of CR (P = 0.02); QOL and physical function were not (all P > 0.05). Findings were similar when patients age 60+ were examined. Relationships between fatigue and role functioning with ICU admission deserve further exploration. CONCLUSIONS: Baseline QOL and physical function tests in this prospective study were not associated with short-term mortality, ICU admission or achievement of CR after the first cycle of chemotherapy.
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Tratamento Farmacológico , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/patologia , Prognóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Unidades de Terapia Intensiva , Leucemia Mieloide Aguda/mortalidade , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Inquéritos e Questionários , Resultado do TratamentoRESUMO
Adult Philadelphia chromosome-positive (Ph+) or BCR-ABL-positive (BCR-ABL+) acute lymphoblastic leukemia (all) is an acute leukemia previously associated with a high relapse rate, short disease-free survival, and poor overall survival. In adults, allogeneic hematopoietic cell transplant in first remission remains the only proven curative strategy for transplant-eligible patients. The introduction of tyrosine kinase inhibitors (tkis) in the treatment of patients with Ph+ or BCR-ABL+ all has significantly improved the depth and duration of complete remission, allowing more patients to proceed to transplantation. Although tkis are now considered a standard of care in this setting, few randomized trials have examined the optimal use of tkis in patients with Ph+ all. Questions of major importance remain, including the best way to administer these medications, the choice of tki to administer, and the schedule and the duration to use. We present the results of a systematic review of the literature with consensus recommendations based on the available evidence.
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Both fatty bone marrow (FBM) and somatic mutations in hematopoietic stem cells (HSCs), also termed clonal hematopoiesis (CH) accumulate with human aging. However it remains unclear whether FBM can modify the evolution of CH. To address this question, we herein present the interaction between CH and FBM in two preclinical male mouse models: after sub-lethal irradiation or after castration. An adipogenesis inhibitor (PPARγ inhibitor) is used in both models as a control. A significant increase in self-renewal can be detected in both human and rodent DNMT3AMut-HSCs when exposed to FBM. DNMT3AMut-HSCs derived from older mice interacting with FBM have even higher self-renewal in comparison to DNMT3AMut-HSCs derived from younger mice. Single cell RNA-sequencing on rodent HSCs after exposing them to FBM reveal a 6-10 fold increase in DNMT3AMut-HSCs and an activated inflammatory signaling. Cytokine analysis of BM fluid and BM derived adipocytes grown in vitro demonstrates an increased IL-6 levels under FBM conditions. Anti-IL-6 neutralizing antibodies significantly reduce the selective advantage of DNMT3AMut-HSCs exposed to FBM. Overall, paracrine FBM inflammatory signals promote DNMT3A-driven clonal hematopoiesis, which can be inhibited by blocking the IL-6 pathway.
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Medula Óssea , Hematopoiese Clonal , Masculino , Humanos , Camundongos , Animais , DNA (Citosina-5-)-Metiltransferases/genética , DNA Metiltransferase 3A , Hematopoese/genéticaRESUMO
Eg5 (kinesin spindle protein) is a microtubule motor protein, essential for centrosome separation during mitosis. This Phase I/II, open-label, multicenter, two-part study investigated AZD4877, a potent Eg5 inhibitor, in patients with acute myeloid leukemia. Primary objectives were to determine the maximum tolerated dose (MTD) (part A), assess efficacy (part B) and determine the pharmacokinetic profile (parts A and B). Secondary objectives included assessment of safety and tolerability. AZD4877 was administered at a range of doses (2, 4, 7, 10, 13, 16 and 18 mg/day) as a 1-hour intravenous infusion on three consecutive days of a continuous 2-week schedule. The MTD in part A was defined as 16 mg/day based on dose-limiting stomatitis at 16 and 18 mg/day, hyperbilirubinemia at 16 mg/day and palmar-plantar erythrodysesthesia syndrome at 18 mg/day. Systemic exposure to AZD4877 generally increased with increasing dose whereas half-life was not dose dependent. No evaluable patients experienced a complete remission (CR) or CR with incomplete blood count recovery (CRi), demonstrating no evidence of AZD4877 efficacy in this population. Evidence of monoasters in all but the 4 mg/day dose group provided proof of mechanism for AZD4877. This study was terminated due to lack of efficacy. (ClinicalTrials.gov identifier NCT00486265).
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Antimitóticos/administração & dosagem , Benzamidas/administração & dosagem , Cinesinas/antagonistas & inibidores , Leucemia Mieloide Aguda/tratamento farmacológico , Pirimidinonas/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Antimitóticos/efeitos adversos , Antimitóticos/farmacocinética , Benzamidas/efeitos adversos , Benzamidas/farmacocinética , Feminino , Humanos , Leucemia Mieloide Aguda/sangue , Masculino , Pessoa de Meia-Idade , Pirimidinonas/efeitos adversos , Pirimidinonas/farmacocinética , Adulto JovemRESUMO
The organization and expression of the beta chain of T cell antigen receptor gene (beta-TCR) and Ig H and L chain genes were analyzed by Southern blot technique in 24 patients with a diagnosis of acute myeloblastic leukemia (AML). Rearrangements of the beta-TCR genes were seen in DNA samples from 3 of the 24 patients. One of these three patients also showed rearrangement of the Ig H chain gene. RNA samples from all three patients expressed a beta-TCR gene transcript on dot blot analysis. However, on Northern blot analysis, one patient expressed an incomplete 1.0 kb transcript and no Ig H chain mRNA, despite a rearranged configuration. The karyotypes of two of these patients showed abnormalities involving chromosome 7. Rearrangements of T cell antigen receptor genes may occur in nonlymphoid malignancy, and is consistent with the concept of lineage infidelity in AML.
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DNA de Neoplasias/análise , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias Leves de Imunoglobulina/genética , Leucemia Mieloide Aguda/genética , Receptores de Antígenos de Linfócitos T/genética , Adolescente , Adulto , Idoso , Aberrações Cromossômicas , Deleção Cromossômica , Cromossomos Humanos 6-12 e X/ultraestrutura , DNA/genética , Feminino , Marcadores Genéticos , Humanos , Leucemia Mieloide Aguda/imunologia , Masculino , Pessoa de Meia-IdadeRESUMO
Using cDNA and genomic probes representing the alpha, beta, and gamma chain of the human T cell receptor genes, we have examined the structure and expression of these genes in 14 human leukemic T cell lines, representing different stages of thymic differentiation, and 15 functional human T cell clones. Rearrangement of the gamma and beta chain genes was found in all of the functional T cell clones and all but one (P30/OKUBO) thymic leukemia cell line; all of the lines that had rearrangement of the beta chain expressed beta mRNA. Expression of the alpha chain was found in all of the functional T cell clones examined, while rearrangement of the alpha chain gene, using currently available probes to the J region, could be shown in 10 of 13 functional clones. In contrast, expression of the alpha chain was found in 6 of 10 leukemic T cell lines, while rearrangement was found in six of these nine cell lines. Of the 14 leukemic cell lines studied for rearrangement of the alpha chain, rearrangement was found in six cases. The data obtained with the cell lines are consistent with an ordered rearrangement and expression of the gamma, beta, and alpha chains of the T cell antigen receptor (TcR) genes. The leukemic cell lines used in the present study have previously been characterized with regard to cell surface antigens and intracellular enzymes. Based on those results a scheme of thymic development was proposed. The developmental stages identified by those studies are not in complete agreement with stages of T cell development, as determined in the present study using molecular probes.
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Leucemia/genética , Receptores de Antígenos de Linfócitos T/genética , Linhagem Celular , DNA/genética , Regulação da Expressão Gênica , Genes , Marcadores Genéticos , Humanos , Leucemia/imunologia , Linfócitos T/imunologiaRESUMO
The nucleotide sequences of 22 human T cell antigen receptor (TcR) beta chain variable region genes isolated from various T lymphocytes have been analyzed. Of the 19 variable gene segment (V beta)-containing sequences, 17 were unique. The V beta gene segments were grouped into 11 families. Comparisons were made with the data of Concannon et al. to unify the nomenclature. The data is consistent with a total V beta gene segment repertoire with a most probable value of 38 members and an upper bound of 104 members at the 95% confidence level. Southern blot data of germline DNA using selected TcR V beta cDNAs as probes support this estimate. The human repertoire is approximately three to four times greater than that reported for the mouse. Explanations for this discrepancy are proposed.
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Receptores de Antígenos de Linfócitos T/genética , Sequência de Bases , DNA/análise , Humanos , Recombinação GenéticaRESUMO
Molecular cloning of the t(10;14)(q24;q11) recurrent breakpoint of T cell acute lymphoblastic leukemia has demonstrated a transcript for the candidate gene TCL3. Characterization of this gene from chromosome segment 10q24 revealed it to be a new homeobox, HOX11. The HOX11 homeodomain is most similar to that of the murine gene Hlx and possesses a markedly glycine-rich variable region and an acidic carboxyl terminus. HOX11, while expressed in liver, was not detected in normal thymus or T cells. This lineage-restricted homeobox gene is deregulated upon translocation into the T cell receptor locus where it may act as an oncogene.
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Regulação Neoplásica da Expressão Gênica , Genes Homeobox , Leucemia-Linfoma de Células T do Adulto/genética , Translocação Genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Northern Blotting , Cromossomos Humanos Par 10 , Cromossomos Humanos Par 14 , Clonagem Molecular , Humanos , Camundongos , Dados de Sequência Molecular , Receptores de Antígenos de Linfócitos T/genética , Mapeamento por Restrição , Homologia de Sequência do Ácido NucleicoRESUMO
Prevention of GVHD is one of the most desirable goals of BMT in aplastic anemia (AA). We reviewed the medical records of 24 consecutive patients treated with BMT for acquired AA using two different GVHD prevention strategies. Ten patients were given alemtuzumab-based GVHD prophylaxis (50-60 mg in three divided doses on days -8, -7 and -6), and 14 patients were given conventional GVHD prophylaxis with calcineurin inhibitors plus MTX before the introduction of the alemtuzumab-based protocols. The incidence of acute, chronic and 'serious GVHD' was significantly reduced in alemtuzumab-treated patients compared to conventionally treated patients [11 vs 64% (P=0.03), 0 vs 78% (P=0.002) and 0 vs 57% (P=0.007), respectively]. Engraftment time and rates of graft failure appeared similar in the two groups. A significantly higher proportion of alemtuzumab-treated patients developed CMV reactivation compared to control patients (83 vs 12%; P=0.03); none developed CMV disease. The rates of other infectious complications did not appear significantly different. Our data suggest that 50-60 mg of alemtuzumab given according to the current schedule significantly reduces the risk of GVHD without increasing the risk of graft failure or serious infections.
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Anemia Aplástica/terapia , Anticorpos Monoclonais/administração & dosagem , Anticorpos Antineoplásicos/administração & dosagem , Transplante de Medula Óssea/efeitos adversos , Doença Enxerto-Hospedeiro/prevenção & controle , Imunossupressores/administração & dosagem , Adulto , Alemtuzumab , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais Humanizados , Anticorpos Antineoplásicos/efeitos adversos , Inibidores de Calcineurina , Estudos de Casos e Controles , Infecções por Citomegalovirus/virologia , Esquema de Medicação , Quimioterapia Combinada , Feminino , Sobrevivência de Enxerto , Humanos , Imunossupressores/efeitos adversos , Masculino , Metotrexato/uso terapêutico , Pessoa de Meia-Idade , Estudos Retrospectivos , Ativação ViralRESUMO
UNLABELLED: Varicella zoster virus (VZV) infection is one of the frequent opportunistic infections after allogeneic bone marrow transplantation, with a high incidence of 30-50%. However, no data have been reported on VZV infection after allogeneic peripheral blood stem cell transplantation (PBSCT). PATIENTS AND METHODS: We report a retrospective analysis of VZV infection in 192 allogeneic PBSCT recipients. Twenty-seven patients (14%) received long-term prophylaxis of low-dose acyclovir (200 mg twice daily orally > or =3 months) for recurrent oral (n=21) or genital herpes simplex virus infection (n=5) or for a previous history of recurrent VZV infection (n=1). RESULTS: Forty-two patients (22%) developed VZV infections: localized (n=37) and disseminated infection (n=5). The incidence of VZV infection at 1 and 3 years was 19.3+/-3.3% and 36.8+/-5.2%, respectively. Complications included post-herpetic neuralgia (n=18, 43%), secondary bacterial infections (n=3), and intracranial hemorrhage (n=1) with 2 deaths. A higher risk factor for VZV infection was pre-transplant diagnosis of a lymphoproliferative disorder (LPD): chronic lymphocytic leukemia, Hodgkin's disease, or non-Hodgkin's lymphoma (P=0.021, 52.5% in LPD vs. 32.6% in non-LPD group). The use of low-dose acyclovir prophylaxis (P=0.043, 14.7% in acyclovir vs. 41.6% in nonacyclovir group) was found to be protective. Although no VZV infection episodes were noted during the period of acyclovir prophylaxis, 3 episodes of VZV infection were noted after acyclovir cessation. CONCLUSION: The incidence of VZV infection after PBSCT was high at 36.8%, with patients transplanted for LPDs at higher risk. The long-term use of low-dose acyclovir may be protective for VZV infection, although it does not completely prevent rebound of late VZV infection.
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Aciclovir/uso terapêutico , Antibioticoprofilaxia , Antivirais/uso terapêutico , Herpes Simples/prevenção & controle , Herpes Zoster/prevenção & controle , Adolescente , Adulto , Idoso , Feminino , Humanos , Transtornos Linfoproliferativos/complicações , Transtornos Linfoproliferativos/diagnóstico , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Transplante de Células-Tronco de Sangue Periférico , Estudos Retrospectivos , Fatores de RiscoRESUMO
The Wilms' tumor 1 (WT1) gene encodes a transcription factor important for normal cellular development and cell survival. The initial discovery of WT1 as the causative gene in an autosomal-recessive condition identified it as a tumor suppressor gene whose mutations are associated with urogenital disease and the development of kidney tumors. However, this view is not in keeping with the frequent finding of wild-type, full-length WT1 in human leukemia, breast cancer and several other cancers including the majority of Wilms' tumors. Rather, these observations suggest that in those conditions, WT1 has an oncogenic role in tumor formation. In this review, we explore the literature supporting both views of WT1 in human cancer and in particular human leukemias. To understand the mechanism by which WT1 can do this, we will also examine its functional activity as a transcription factor and the influence of protein partners on its dual behavior.
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Genes do Tumor de Wilms , Leucemia/genética , Oncogenes , Proteínas WT1/fisiologia , Diferenciação Celular , Sobrevivência Celular , Hematopoese , Humanos , Leucemia/tratamento farmacológico , Leucemia/mortalidade , Prognóstico , Proteínas WT1/análise , Proteínas WT1/químicaRESUMO
OBJECTIVES: Exhaled breath condensate (EBC) is a noninvasive means of sampling the airways that has shown significant promise in the diagnosis of many disorders. There have been no reports of its usefulness in the detection of galactomannan (GM), a component of the cell wall of Aspergillus. The suitability of EBC for the detection of GM for the diagnosis of invasive aspergillosis (IA) using the Platelia Aspergillus enzyme-linked immunosorbent assay was investigated. METHODS: Prospective, cross-sectional study of lung transplant recipient and haemotologic malignancy patients at a university centre. EBC samples were compared to concomitant bronchoalveolar lavage (BAL) samples among lung transplant recipients and healthy controls. EBC was collected over 10 minutes using a refrigerated condenser according to the European Respiratory Society/American Thoracic Society recommendations, with the BAL performed immediately thereafter. RESULTS: A total of 476 EBC specimens with 444 matched BAL specimens collected from lung transplant recipients (n = 197) or haemotologic malignancy patients (n = 133) were examined. Both diluted and untreated EBC optical density (OD) values (0.0830, interquartile range (IQR) 0.0680-0.1040; and 0.1130, IQR 0.0940-0.1383), respectively, from all patients regardless of clinical syndrome were significantly higher than OD values in healthy control EBCs (0.0508, IQR 0.0597-0.0652; p < 0.0001). However, the OD index values did not correlate with the diagnosis of IA (44 samples were associated with IA). Furthermore, no significant correlation was found between EBC GM and the matched BAL specimen. CONCLUSIONS: GM is detectable in EBC; however, no correlation between OD index values and IA was noted in lung transplant recipients.
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Aspergillus/química , Líquido da Lavagem Broncoalveolar/química , Neoplasias Hematológicas/microbiologia , Aspergilose Pulmonar Invasiva/diagnóstico , Mananas/isolamento & purificação , Idoso , Aspergillus/isolamento & purificação , Testes Respiratórios , Líquido da Lavagem Broncoalveolar/microbiologia , Estudos de Casos e Controles , Parede Celular/química , Estudos Transversais , Expiração , Feminino , Galactose/análogos & derivados , Humanos , Hospedeiro Imunocomprometido , Aspergilose Pulmonar Invasiva/microbiologia , Transplante de Pulmão , Masculino , Pessoa de Meia-Idade , Estudos ProspectivosRESUMO
Bone marrow transplantation has become an accepted modality in the treatment of acute leukemia. With this therapy, it is possible to obtain long-term disease-free survival. However, leukemia recurs occasionally. In most cases, leukemic relapse is of recipient origin. There have been several reports, though, of leukemia developing in donor cells. These cases have been limited to instances in which there is an easily identifiable chromosome difference or abnormality, usually a sex chromosome. In this paper we describe the use of restriction fragment-length polymorphism analysis to determine the origin of recurrent leukemia cells in which no identifying chromosome was present. We found that the leukemia had recurred in recipient cells. We also were able to demonstrate the presence of normal hemopoietic cells of donor origin.
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Transplante de Medula Óssea , Leucemia Mieloide Aguda/terapia , Adulto , Aberrações Cromossômicas , Mapeamento Cromossômico , Citogenética , DNA/análise , Enzimas de Restrição do DNA/genética , Enzimas de Restrição do DNA/metabolismo , Humanos , Leucemia Mieloide Aguda/patologia , Masculino , Polimorfismo Genético , Formação de RosetaRESUMO
A 6-yr-old girl with T cell acute lymphoblastic leukemia (ALL) is described. She had a mediastinal mass and her leukemic cells expressed T cell-associated antigens (Leu 1+, OKT3+, OKT9+, and OKT10+). When we examined genomic DNA from the leukemic cells, we detected Ig mu-chain gene rearrangement with germ-line configuration of light chain genes. As reported recently, detecting Ig gene rearrangement has become an important procedure for further classifying B cell precursor cells. This case, however, suggests that there is also heterogeneity among patients with T cell ALL, not only at the level of cell surface phenotypes, but also at the level of the Ig gene. These findings have major implications when we consider both the ontogenesis of these leukemic cells and the normal differentiation of human lymphocytes.
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Cadeias Pesadas de Imunoglobulinas/genética , Cadeias mu de Imunoglobulina/genética , Leucemia Linfoide/genética , Linfócitos T/imunologia , Antígenos de Superfície/imunologia , Diferenciação Celular , Transformação Celular Neoplásica/imunologia , Transformação Celular Neoplásica/patologia , Criança , Feminino , Humanos , Leucemia Linfoide/imunologia , Leucemia Linfoide/patologia , Linfócitos T/citologia , Linfócitos T/patologiaRESUMO
55 samples representing Hodgkin's and non-Hodgkin's lymphoma and other hyperplastic lesions of the lymph node were examined for rearrangement of the beta chain of the T cell antigen receptor (TcR) and Ig genes. In non-Hodgkin's lymphoma, rearrangement of TcR beta was found in all 14 T cell lymphomas and in two of the seven B cell lymphomas. Ig gene rearrangement was found in none of the 14 T cell lymphomas and in all seven B cell lymphomas. We also examined DNA from lymph nodes in which the lineage of the malignant cell is not clear. Rearrangement of TcR beta was found in all five lymphoepitheloid cell (Lennert's) lymphomas; four of eight Hodgkin's lymphomas; seven of ten Ki 1+ lymphomas; and all nine cases of angioimmunoblastic lymphoadenopathy (AIL). Ig gene rearrangement was found in none of five lymphoepitheloid cell lymphomas; none of eight Hodgkin's lymphomas; three of ten Ki 1+ lymphomas; and four of nine cases of AIL. These findings indicate that genetic studies of TcR and Ig genes are useful in identifying the presence of a clonal population in a lymph node, in determining the extent of the clonal population, and aid in identifying lineage. Of special interest was the finding that some cases of Hodgkin's lymphoma and AIL contain clonal rearrangement of the TcR genes, which suggests that in those cases the malignant cells may be of T cell origin.
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Genes , Imunoglobulinas/genética , Linfoma/imunologia , Transtornos Linfoproliferativos/imunologia , Receptores de Antígenos de Linfócitos T/genética , DNA/isolamento & purificação , Humanos , Linfonodos/imunologia , Linfoma/genética , Transtornos Linfoproliferativos/genética , Substâncias Macromoleculares , Hibridização de Ácido NucleicoRESUMO
Using a newly isolated cDNA clone encoding the TCR-delta gene and genomic probes, we have analyzed T cell receptor (TCR) delta gene rearrangement in 19 patients with T cell acute lymphoblastic leukemia (T-ALL) and 29 patients with B-precursor ALL. Five out of seven CD3- T-ALL and 4 of 12 CD3+ T-ALL showed bi-allelic rearrangements of the TCR-delta gene. In three CD3+ patients, a single allelic TCR-delta gene rearrangement was observed with rearrangement of the TCR-alpha gene on the other allele. In five CD3+ patients with bi-allelic rearrangements of the TCR-alpha gene, the TCR-delta gene locus was deleted. Transcription of the TCR-delta gene was also analyzed in six T-ALL. Five patients expressed TCR-delta transcripts. Only one T-ALL, presumably derived from the most immature T lineage cells, did not have TCR-delta transcripts, but expressed TCR-gamma and 1.0-kb truncated TCR-beta transcripts. In B-precursor ALL, 20 patients (69%) showed rearrangements of the TCR-delta gene. The frequency of TCR-delta gene rearrangement was higher than TCR-alpha (59%), gamma (52%), or beta (31%) genes. These findings suggest that TCR-alpha gene rearrangements may take place after rearrangements of the TCR-delta gene with concomitant deletion of rearranged TCR-delta genes in T cell differentiation. Among leukemic cells of B lineage, the TCR-delta gene is the earliest rearranging TCR gene, followed by TCR-gamma and beta gene rearrangements.
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Rearranjo Gênico da Cadeia beta dos Receptores de Antígenos dos Linfócitos T , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Southern Blotting , DNA/análise , Desoxirribonuclease BamHI/metabolismo , Desoxirribonuclease EcoRI/metabolismo , HumanosRESUMO
The development of a cell culture system efficient in the establishment of lymphoma cell lines has made it possible to dissect basic biological and molecular aspects of lymphoma cells. We have established a lymphoma cell line from a patient with B cell lymphoma. The cell line has a complex karyotype with translocations involving bands 8q24, 14q32, and 18q21. Molecular analysis revealed that the Myc gene was rearranged; we were unable to demonstrate rearrangement of the Bcl-2 gene. Evaluation of the structure of the heavy chain Ig genes revealed that the cell line carried the same rearrangements as the cells from which the cell line was derived. The pattern of rearrangement, however, was unusual in that there were at least four rearranged bands when DNA cut with HindIII was probed with a fragment of the heavy chain joining region. To further characterize the cell line, subclones were derived. Individual subclones had the same pattern of rearrangement as the parent cell line. The results of these studies provide evidence that multiple rearranged Ig genes may be present in a single clone of cells.
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Rearranjo Gênico , Genes de Imunoglobulinas , Linfoma/imunologia , Herpesvirus Humano 4/genética , Humanos , Cariotipagem , Linfoma/genética , Translocação Genética , Células Tumorais CultivadasRESUMO
We have analyzed the configuration of the T cell receptor (TCR) alpha gene using newly developed genomic joining region (J alpha) probes, which cover approximately 80 kb of the J alpha region upstream from the constant region in 19 patients with T cell acute lymphoblastic leukemia (T-ALL) and in three CD3- leukemic T cell lines (HSB2, CEM, and MOLT4). In parallel, transcription of the TCR-alpha, beta, and gamma genes was examined in 11 of these patients and in the T cell lines. All T-ALL and the three T cell lines exhibited both TCR-gamma and beta gene rearrangements. 8 of 10 T-ALL and all T cell lines expressed TCR-gamma transcripts. All samples tested expressed both TCR-beta and CD3-gamma transcripts. TCR alpha transcripts were only observed in CD3+ T-ALL but not in CD3- T-ALL or the CD3- cell lines. Among the CD3+ T-ALL, eight had TCR-alpha gene rearrangements. In addition, TCR-alpha gene rearrangements were detected in one CD3- T-ALL and all three T cell lines. These leukemic cells may represent a transient stage between rearrangement and expression and provide an opportunity for analyzing the mechanism regulating the expression of the TCR-alpha gene.