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1.
Proc Natl Acad Sci U S A ; 119(30): e2122476119, 2022 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-35867833

RESUMO

During organismal development, homeostasis, and disease, Dishevelled (Dvl) proteins act as key signaling factors in beta-catenin-dependent and beta-catenin-independent Wnt pathways. While their importance for signal transmission has been genetically demonstrated in many organisms, our mechanistic understanding is still limited. Previous studies using overexpressed proteins showed Dvl localization to large, punctate-like cytoplasmic structures that are dependent on its DIX domain. To study Dvl's role in Wnt signaling, we genome engineered an endogenously expressed Dvl2 protein tagged with an mEos3.2 fluorescent protein for superresolution imaging. First, we demonstrate the functionality and specificity of the fusion protein in beta-catenin-dependent and beta-catenin-independent signaling using multiple independent assays. We performed live-cell imaging of Dvl2 to analyze the dynamic formation of the supramolecular cytoplasmic Dvl2_mEos3.2 condensates. While overexpression of Dvl2_mEos3.2 mimics the previously reported formation of abundant large "puncta," supramolecular condensate formation at physiological protein levels is only observed in a subset of cells with approximately one per cell. We show that, in these condensates, Dvl2 colocalizes with Wnt pathway components at gamma-tubulin and CEP164-positive centrosomal structures and that the localization of Dvl2 to these condensates is Wnt dependent. Single-molecule localization microscopy using photoactivated localization microscopy (PALM) of mEos3.2 in combination with DNA-PAINT demonstrates the organization and repetitive patterns of these condensates in a cell cycle-dependent manner. Our results indicate that the localization of Dvl2 in supramolecular condensates is coordinated dynamically and dependent on cell state and Wnt signaling levels. Our study highlights the formation of endogenous and physiologically regulated biomolecular condensates in the Wnt pathways at single-molecule resolution.


Assuntos
Condensados Biomoleculares , Proteínas Desgrenhadas , Proteínas Wnt , Via de Sinalização Wnt , Condensados Biomoleculares/química , Condensados Biomoleculares/metabolismo , Proteínas Desgrenhadas/química , Proteínas Desgrenhadas/metabolismo , Humanos , Microscopia de Fluorescência/métodos , Domínios Proteicos , Proteínas Wnt/metabolismo , beta Catenina/metabolismo
2.
Haematologica ; 2023 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-37941409

RESUMO

The role of autologous-allogeneic tandem stem cell transplantation (alloTSCT) followed by maintenance as upfront treatment for multiple myeloma (MM) is controversial. Between 2008 and 2014 a total of 217 MM patients with a median age of 51 years were included by 20 German centers within an open-label, parallel-group, multi-center clinical trial to compare alloTSCT to auto tandem transplantation TSCT (autoTSCT) followed by a 2-year maintenance therapy with thalidomide (100 mg/d) in both arms with respect to relapse/progression-free survival (PFS) and other relevant outcomes. A total of 178 patients underwent second SCT (allo n = 132 and auto n = 46). PFS at 4 years after the second SCT was 47% (CI: 38-55%) for alloTSCT and 35% (CI: 21-49%) for autoTSCT (p = 0.26). This difference increased to 22% at 8 years (p = 0.10). The cumulative incidences of non-relapse mortality (NRM) and of relapse at 4 years were 13% (CI: 8-20%) and 2% (CI: 0.3-2%) (p = 0.044) and 40% (CI: 33-50%) and 63% (CI: 50-79%) for alloTSCT and autoTSCT (p = 0.04), respectively. The difference for relapse/progression increased to 33% (alloTSCT: 44%, autoTSCT: 77%) at a median follow-up of 82 months (p = 0.002). Four-year OS was 66% (CI: 57-73%) for alloTSCT and 66% (CI: 50-78%) for auto TSCT (p = 0.91) and 8-year OS was 52% and 50% (p = 0.87), respectively. AlloTSCT followed by thalidomide maintenance reduced the rate of recurrence or progression during a follow-up period of up to 10 years but failed to improve PFS significantly.

3.
Haematologica ; 108(2): 543-554, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35522148

RESUMO

Histone methylation-modifiers, such as EZH2 and KMT2D, are recurrently altered in B-cell lymphomas. To comprehensively describe the landscape of alterations affecting genes encoding histone methylation-modifiers in lymphomagenesis we investigated whole genome and transcriptome data of 186 mature B-cell lymphomas sequenced in the ICGC MMML-Seq project. Besides confirming common alterations of KMT2D (47% of cases), EZH2 (17%), SETD1B (5%), PRDM9 (4%), KMT2C (4%), and SETD2 (4%), also identified by prior exome or RNA-sequencing studies, we here found recurrent alterations to KDM4C in chromosome 9p24, encoding a histone demethylase. Focal structural variation was the main mechanism of KDM4C alterations, and was independent from 9p24 amplification. We also identified KDM4C alterations in lymphoma cell lines including a focal homozygous deletion in a classical Hodgkin lymphoma cell line. By integrating RNA-sequencing and genome sequencing data we predict that KDM4C structural variants result in loss-offunction. By functional reconstitution studies in cell lines, we provide evidence that KDM4C can act as a tumor suppressor. Thus, we show that identification of structural variants in whole genome sequencing data adds to the comprehensive description of the mutational landscape of lymphomas and, moreover, establish KDM4C as a putative tumor suppressive gene recurrently altered in subsets of B-cell derived lymphomas.


Assuntos
Linfoma de Células B , Linfoma , Humanos , Histonas/metabolismo , Histona Desmetilases/genética , Homozigoto , Deleção de Sequência , Linfoma/genética , Linfoma de Células B/genética , Sequenciamento Completo do Genoma , RNA , Histona Desmetilases com o Domínio Jumonji/genética , Histona Desmetilases com o Domínio Jumonji/química , Histona Desmetilases com o Domínio Jumonji/metabolismo , Histona-Lisina N-Metiltransferase/genética
4.
Haematologica ; 106(8): 2224-2232, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32675228

RESUMO

It has been suggested that B-cell receptor (BCRs) stimulation by specific antigens plays a pathogenic role in diffuse large B-cell lymphoma (DLBCL). Here, it was the aim to screen for specific reactivities of DLBCL-BCRs in the spectrum of autoantigens and antigens of infectious origin. Arsenite resistance protein 2 (Ars2) was identified as the BCR target of 3/5 ABC-type DLBCL cell lines and 2/11 primary DLBCL cases. Compared to controls, Ars2 was hypo-phosphorylated exclusively in cases and cell lines with Ars2-specific BCRs. In a validation cohort, hypo-phosphorylated Ars2 was found in 8/31 ABC-type, but only 1/20 germinal center B cell (GBC)-like type DLBCL. Incubation with Ars2 induced BCR-pathway activation and increased proliferation, while an Ars2/ETA-toxin conjugate induced killing of cell lines with Ars2-reactive BCRs. Ars2 appears to play a role in a subgroup of ABC-type DLBCLs. Moreover, transformed DLBCL lines with Ars2-reactive BCRs still show growth advantage after incubation with Ars2. These results provide knowledge about the pathogenic role of a specific antigen stimulating the BCR pathway in DLCBL.


Assuntos
Autoantígenos , Linfoma Difuso de Grandes Células B , Linfócitos B , Humanos , Linfoma Difuso de Grandes Células B/genética , Receptores de Antígenos de Linfócitos B/genética , Transdução de Sinais
5.
Ann Hematol ; 100(4): 1031-1038, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33242101

RESUMO

In elderly patients (pts) with aggressive B cell lymphoma (aNHL), curative treatment often cannot be administered because of comorbidities and tolerability. We analyzed the influence of age in pts > 60 years receiving the R-CHOP-14 regimen within different prospective DSHNHL trials. Of the RICOVER-60 trial and CHOP-R-ESC trials, 1171 aNHL pts were included in this retrospective analysis of age-dependent event-free survival (EFS), progression-free survival (PFS), and overall survival (OS). All patients received prophylactic G-CSF, and anti-infective prophylaxis with amphotericin B mouth wash and oral fluorchinolone was optional. In the CHOP-R-ESC trials, prophylaxis was augmented to include mandatory continuous orally administered aciclovir and a pneumocystis prophylaxis with cotrimoxazole as well as oral fluorchinolones during neutropenia. The patient population was separated into 4 age groups (61-65 years, 66-70 years, 71-75 years, and 76-80 years). The results from the RICOVER-60 trial were subsequently confirmed in the following CHOP-R-ESC trials by a multivariate analysis adjusted for IPI factors and gender. Significant differences (p < 0.001) in EFS, PFS, and OS were seen between age groups (RICOVER-60). Hematotoxicity, infections, and TRM increased with age. TRM was significantly elevated in the age group 76-80 years. Therefore, this analysis shows that an age above 75 years defines an especially vulnerable patient population when being treated with chemoimmunotherapy for aNHL. Prophylactic anti-infective drugs are essential and clinically effective in reducing morbidity when treating elderly aNHL pts.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Linfoma de Células B/tratamento farmacológico , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Antibioticoprofilaxia , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ensaios Clínicos Fase II como Assunto/estatística & dados numéricos , Ensaios Clínicos Fase III como Assunto/estatística & dados numéricos , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Relação Dose-Resposta a Droga , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Estudos de Viabilidade , Feminino , Humanos , Estimativa de Kaplan-Meier , Linfoma de Células B/mortalidade , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto/estatística & dados numéricos , Prednisona/administração & dosagem , Prednisona/efeitos adversos , Intervalo Livre de Progressão , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Estudos Retrospectivos , Rituximab/administração & dosagem , Rituximab/efeitos adversos , Resultado do Tratamento , Vincristina/administração & dosagem , Vincristina/efeitos adversos
6.
Lancet ; 393(10168): 229-240, 2019 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-30522922

RESUMO

BACKGROUND: Based on the encouraging activity and manageable safety profile observed in a phase 1 study, the ECHELON-2 trial was initiated to compare the efficacy and safety of brentuximab vedotin, cyclophosphamide, doxorubicin, and prednisone (A+CHP) versus cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) for the treatment of CD30-positive peripheral T-cell lymphomas. METHODS: ECHELON-2 is a double-blind, double-dummy, randomised, placebo-controlled, active-comparator phase 3 study. Eligible adults from 132 sites in 17 countries with previously untreated CD30-positive peripheral T-cell lymphomas (targeting 75% with systemic anaplastic large cell lymphoma) were randomly assigned 1:1 to receive either A+CHP or CHOP for six or eight 21-day cycles. Randomisation was stratified by histological subtype according to local pathology assessment and by international prognostic index score. All patients received cyclophosphamide 750 mg/m2 and doxorubicin 50 mg/m2 on day 1 of each cycle intravenously and prednisone 100 mg once daily on days 1 to 5 of each cycle orally, followed by either brentuximab vedotin 1·8 mg/kg and a placebo form of vincristine intravenously (A+CHP group) or vincristine 1·4 mg/m2 and a placebo form of brentuximab vedotin intravenously (CHOP group) on day 1 of each cycle. The primary endpoint, progression-free survival according to blinded independent central review, was analysed by intent-to-treat. This trial is registered with ClinicalTrials.gov, number NCT01777152. FINDINGS: Between Jan 24, 2013, and Nov 7, 2016, 601 patients assessed for eligibility, of whom 452 patients were enrolled and 226 were randomly assigned to both the A+CHP group and the CHOP group. Median progression-free survival was 48·2 months (95% CI 35·2-not evaluable) in the A+CHP group and 20·8 months (12·7-47·6) in the CHOP group (hazard ratio 0·71 [95% CI 0·54-0·93], p=0·0110). Adverse events, including incidence and severity of febrile neutropenia (41 [18%] patients in the A+CHP group and 33 [15%] in the CHOP group) and peripheral neuropathy (117 [52%] in the A+CHP group and 124 [55%] in the CHOP group), were similar between groups. Fatal adverse events occurred in seven (3%) patients in the A+CHP group and nine (4%) in the CHOP group. INTERPRETATION: Front-line treatment with A+CHP is superior to CHOP for patients with CD30-positive peripheral T-cell lymphomas as shown by a significant improvement in progression-free survival and overall survival with a manageable safety profile. FUNDING: Seattle Genetics Inc, Millennium Pharmaceuticals Inc, a wholly owned subsidiary of Takeda Pharmacuetical Company Limited, and National Institutes of Health National Cancer Institute Cancer Center.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Imunoconjugados/administração & dosagem , Fatores Imunológicos/administração & dosagem , Linfoma Anaplásico de Células Grandes/tratamento farmacológico , Adulto , Idoso , Antineoplásicos/administração & dosagem , Brentuximab Vedotin , Ciclofosfamida/administração & dosagem , Intervalo Livre de Doença , Método Duplo-Cego , Doxorrubicina/administração & dosagem , Feminino , Humanos , Imunoconjugados/efeitos adversos , Fatores Imunológicos/efeitos adversos , Análise de Intenção de Tratamento , Masculino , Pessoa de Meia-Idade , Prednisona/administração & dosagem , Vincristina/administração & dosagem
7.
Ann Hematol ; 99(5): 1073-1079, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32125469

RESUMO

To assess the efficacy of radioimmunotherapy (RIT) with 90yttrium-ibrutinib-tiuxetan (90Y-IT) in mantle cell lymphoma, data from 90 patients registered in the RIT Network with a median follow-up (FU) of 5.5 years after RIT were evaluated. 90Y-IT was given as first-line therapy in 45 (50%) and for relapse in 45 (50%) patients. Most patients received 90Y-IT as consolidation after chemoimmunotherapy in first line (98%) and in relapse (53%). As a first-line treatment, 30 patients (pts.) (67%) achieved CR, 10 pts. (22%) PR%. and 1 pt. (2%) PD, and for 4 pts. (9%), no response data was available. At relapse, CR was achieved in 17 pts. (38%), PR in 6 pts. (13%), SD in 2 pts. (4%), and 6 pts. (13%) had PD, while the response was not documented for 14 pts. (31%). After a median FU of 5.5 years, median PFS for all patients was 2.11 (95% CI, 1.03-2.32) years, and median OS was 4.05 (95% CI, 2.79-7.21) years. Eleven pts. (12.2%) developed second malignancy. In conclusion, this is the largest report of MCL pts. treated with 90Y-IT to date. 90Y-IT was most often used as consolidation after first- and second-line chemotherapy and may improve the results achieved using chemoimmunotherapy alone. However, the results are less encouraging compared to treatment with small molecules such as ibrutinib.


Assuntos
Linfoma de Célula do Manto/mortalidade , Linfoma de Célula do Manto/radioterapia , Radioimunoterapia , Sistema de Registros , Adulto , Idoso , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Taxa de Sobrevida
8.
Br J Haematol ; 184(6): 949-956, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30515751

RESUMO

To assess efficacy of radioimmunotherapy (RIT) in follicular lymphoma, data from 281 patients collected in the RIT Network, with a median follow-up of 8·2 years after RIT were analysed. RIT was given at first line in 18·5% and at relapse in 81·5%. Following first line therapy, 76·9% achieved complete remission (CR), 9·6% partial remission (PR), 1·9% stable disease (SD) and 1·9% had progressive disease (PD); response was not documented in 9·7%. At relapse, the rate of CR was 48·5% and that of PR was 16·6%, SD 2·6% and PD 10·5%; response was not documented in 21·8%. After median follow-up of 8·2 years, median progression-free survival (PFS) for all was 2·54 years, median overall survival (OS) was not reached. Median PFS and OS (both not reached) were significantly better in first line, compared to RIT at relapse (PFS, 2·11 years; OS, 10·8 years; P = 0·0037 and P = 0·0021, respectively). Overall 8-year PFS was 33·9%, 53·6% for first line and 29·6% for relapsed individuals. Overall 8-year OS was 58·8%, 78·1% for first line and 54·5% for relapsed patients. Thirty-five patients (12·5%) developed secondary malignancy and 16 patients (5·7%) experienced transformation into aggressive lymphoma. RIT is a safe and effective treatment option for follicular lymphoma, both at front line and relapse with an 8-year PFS of 53·6% and 29·6%, respectively.


Assuntos
Linfoma Folicular/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Radioimunoterapia , Sistema de Registros , Fatores de Tempo , Resultado do Tratamento
9.
Br J Haematol ; 187(5): 627-637, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31407320

RESUMO

Mutations in SOCS1 are frequent in primary mediastinal B-cell lymphoma and classical Hodgkin lymphoma. In the latter, SOCS1 mutations affect the length of the encoded protein (major mutations) and are associated with shorter patient survival. Two independent studies examined the prognostic impact of SOCS1 mutations in diffuse large B-cell lymphoma (DLBCL) and showed differing results. This may be due to the small number of included patients, the heterogeneity of patients' demographics and the distinct treatment schemes in these studies. To overcome the size limitations of these previous studies, we assessed SOCS1 mutations in the RICOVER-60 cohort. The cohort uniformly consists of elderly patients (aged 61-80 years) treated with the CHOP-14 scheme (cyclophosphamide, hydroxydaunorubicin, vincristine, prednisolone at 14-day intervals) with or without an additional rituximab treatment. Patient outcomes were analysed with regard to overall SOCS1 mutation frequency, major and minor mutations and a novel impact-based classifier - against the treatment modalities. Patients harbouring putative pathogenic SOCS1 mutations showed significant reduced overall survival within the CHOP plus rituximab group. Hence, putative pathogenic SOCS1 mutations seem to efface the beneficial effect of the therapeutic CD20 antibody. Comparing published data of whole exome and transcriptome sequencing of a large DLBCL cohort confirmed that predicted deleterious SOCS1 mutations forecast pre-eminent survival in early onset DLBCL.


Assuntos
Biomarcadores Tumorais/genética , Linfoma Difuso de Grandes Células B/genética , Mutação , Proteína 1 Supressora da Sinalização de Citocina/genética , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Estudos de Coortes , Ciclofosfamida/uso terapêutico , Análise Mutacional de DNA/métodos , DNA de Neoplasias/genética , Doxorrubicina/uso terapêutico , Feminino , Genótipo , Humanos , Estimativa de Kaplan-Meier , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Taxa de Mutação , Proteínas de Neoplasias/genética , Prednisolona/uso terapêutico , Prognóstico , Rituximab/administração & dosagem , Resultado do Tratamento , Vincristina/uso terapêutico
10.
Haematologica ; 104(5): 955-962, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30514803

RESUMO

Standard first-line therapy of chronic myeloid leukemia is treatment with imatinib. In the randomized German Chronic Myeloid Leukemia-Study IV, more potent BCR-ABL inhibition with 800 mg ('high-dose') imatinib accelerated achievement of a deep molecular remission. However, whether and when a de-escalation of the dose intensity under high-dose imatinib can be safely performed without increasing the risk of losing deep molecular response is unknown. To gain insights into this clinically relevant question, we analyzed the outcome of imatinib dose reductions from 800 mg to 400 mg daily in the Chronic Myeloid Leukemia-Study IV. Of the 422 patients that were randomized to the 800 mg arm, 68 reduced imatinib to 400 mg after they had achieved at least a stable major molecular response. Of these 68 patients, 61 (90%) maintained major molecular remission on imatinib at 400 mg. Five of the seven patients who lost major molecular remission on the imatinib standard dose regained major molecular remission while still on 400 mg imatinib. Only two of 68 patients had to switch to more potent kinase inhibition to regain major molecular remission. Importantly, the lengths of the intervals between imatinib high-dose treatment before and after achieving major molecular remission were associated with the probabilities of maintaining major molecular remission with the standard dose of imatinib. Taken together, the data support the view that a deep molecular remission achieved with high-dose imatinib can be safely maintained with standard dose in most patients. Study protocol registered at clinicaltrials.gov 00055874.


Assuntos
Antineoplásicos/uso terapêutico , Mesilato de Imatinib/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Suspensão de Tratamento/estatística & dados numéricos , Idoso , Relação Dose-Resposta a Droga , Feminino , Seguimentos , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Indução de Remissão , Estudos Retrospectivos , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento
11.
Biol Blood Marrow Transplant ; 24(2): 276-281, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29037891

RESUMO

Novel induction agents markedly improved remission rates in multiple myeloma (MM), and the continued use of chemotherapy for CD34+ stem cell mobilization (SCM) has been questioned. We examined the additional effect of chemotherapy in SCM regarding remission status/morbidity. We reviewed 236 consecutive MM patients (aged 36 to 75 years) with first autologous stem cell transplantation from January 2009 to March 2016 after chemotherapy-based SCM. Responses were measured by changes in intact Ig and free light chain levels before and after chemomobilization (International Myeloma Working Group [IMWG] criteria). Most patients (225/236, 95.3%) received novel induction regimens, which were bortezomib-based (n = 223) and/or lenalidomide-based (n = 19). Most patients (170/190, 89.5%) achieved at least partial remission postinduction and pre-SCM. Stem cells were mobilized with granulocyte colony-stimulating factor and cyclophosphamide-based (212/227, 93.4%) or etoposide-based (15/227, 6.6%) regimens. There were insignificant changes in serum Ig and free light chain levels before and after chemomobilization either in the whole cohort or subgroups. Significant improvements of the IMWG remission status were documented in only 7 of 236 patients (3.0%). Sixty-seven patients (28.4%) developed chemotherapy-related complications (neutropenic fever, sepsis, and others), resulting in 9 hospitalizations (3.8%). Our study suggests that although causing significant morbidity, chemotherapy-based mobilization fails to improve remission status. The value of incorporating additional chemotherapy for SCM is thus not evident.


Assuntos
Mobilização de Células-Tronco Hematopoéticas/métodos , Mieloma Múltiplo/tratamento farmacológico , Paraproteínas/efeitos dos fármacos , Indução de Remissão/métodos , Adulto , Idoso , Feminino , Mobilização de Células-Tronco Hematopoéticas/mortalidade , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/patologia , Estudos Retrospectivos , Análise de Sobrevida , Transplante Autólogo , Resultado do Tratamento
12.
Blood ; 127(22): 2732-41, 2016 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-27048211

RESUMO

The adaptor protein MYD88 is critical for relaying activation of Toll-like receptor signaling to NF-κB activation. MYD88 mutations, particularly the p.L265P mutation, have been described in numerous distinct B-cell malignancies, including diffuse large B-cell lymphoma (DLBCL). Twenty-nine percent of activated B-cell-type DLBCL (ABC-DLBCL), which is characterized by constitutive activation of the NF-κB pathway, carry the p.L265P mutation. In addition, ABC-DLBCL frequently displays focal copy number gains affecting BCL2 Here, we generated a novel mouse model in which Cre-mediated recombination, specifically in B cells, leads to the conditional expression of Myd88(p.L252P) (the orthologous position of the human MYD88(p.L265P) mutation) from the endogenous locus. These mice develop a lymphoproliferative disease and occasional transformation into clonal lymphomas. The clonal disease displays the morphologic and immunophenotypical characteristics of ABC-DLBCL. Lymphomagenesis can be accelerated by crossing in a further novel allele, which mediates conditional overexpression of BCL2 Cross-validation experiments in human DLBCL samples revealed that both MYD88 and CD79B mutations are substantially enriched in ABC-DLBCL compared with germinal center B-cell DLBCL. Furthermore, analyses of human DLBCL genome sequencing data confirmed that BCL2 amplifications frequently co-occurred with MYD88 mutations, further validating our approach. Finally, in silico experiments revealed that MYD88-mutant ABC-DLBCL cells in particular display an actionable addiction to BCL2. Altogether, we generated a novel autochthonous mouse model of ABC-DLBCL that could be used as a preclinical platform for the development and validation of novel therapeutic approaches for the treatment of ABC-DLBCL.


Assuntos
Linfócitos B/metabolismo , Transformação Celular Neoplásica/metabolismo , Linfoma Difuso de Grandes Células B/metabolismo , Mutação de Sentido Incorreto , Fator 88 de Diferenciação Mieloide/biossíntese , Neoplasias Experimentais/metabolismo , Animais , Linfócitos B/patologia , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Humanos , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/patologia , Camundongos , Camundongos Transgênicos , Fator 88 de Diferenciação Mieloide/genética , Neoplasias Experimentais/genética , Neoplasias Experimentais/patologia , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Proteínas Proto-Oncogênicas c-bcl-2/genética
13.
Haematologica ; 103(7): 1182-1190, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29567771

RESUMO

A linear progression model of follicular lymphomas (FL) FL1, FL2 and FL3A has been favored, since FL3A often co-exist with an FL1/2 component. FL3B, in contrast, is thought to be more closely related to diffuse large B-cell lymphoma (DLBCL), and both are often simultaneously present in one tumor (DLBCL/FL3B). To obtain more detailed insights into follicular lymphoma progression, a comprehensive analysis of a well-defined set of FL1/2 (n=22), FL3A (n=16), FL3B (n=6), DLBCL/FL3B (n=9), and germinal center B-cell-type diffuse large B-cell lymphoma (n=45) was undertaken using gene expression profiling, immunohistochemical stainings and genetic analyses by fluorescence in situ hybridization. While immunohistochemical (CD10, IRF4/MUM1, Ki67, BCL2, BCL6) and genetic profiles (translocations of BCL2, BCL6 and MYC) delineate FL1-3A from FL3B and DLBCL/FL3B, significant differences were observed between FL1/2 and FL3A upon gene expression profiling. Interestingly, FL3B turned out to be closely related to FL3A, not categorizing within a separate gene expression cluster, and both FL3A and FL3B showed overlapping profiles in between FL1/2 and diffuse large B-cell lymphoma. Finally, based upon their gene expression pattern, DLBCL/FL3B represent a composite form of FL3B and DLBCL, with the majority of samples more closely resembling the latter. The fact that gene expression profiling clearly separated FL1/2 from both FL3A and FL3B suggests a closer biological relationship between the latter. This notion, however, is in contrast to immunohistochemical and genetic profiles of the different histological FL subtypes that point to a closer relationship between FL1/2 and FL3A, and separates them from FL3B.


Assuntos
Estudos de Associação Genética , Linfoma Folicular/genética , Linfoma Folicular/patologia , Transcriptoma , Adulto , Idoso , Biomarcadores Tumorais , Biologia Computacional/métodos , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Gradação de Tumores
15.
Proc Natl Acad Sci U S A ; 112(38): E5261-70, 2015 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-26351698

RESUMO

Despite the established role of the transcription factor MYC in cancer, little is known about the impact of a new class of transcriptional regulators, the long noncoding RNAs (lncRNAs), on MYC ability to influence the cellular transcriptome. Here, we have intersected RNA-sequencing data from two MYC-inducible cell lines and a cohort of 91 B-cell lymphomas with or without genetic variants resulting in MYC overexpression. We identified 13 lncRNAs differentially expressed in IG-MYC-positive Burkitt lymphoma and regulated in the same direction by MYC in the model cell lines. Among them, we focused on a lncRNA that we named MYC-induced long noncoding RNA (MINCR), showing a strong correlation with MYC expression in MYC-positive lymphomas. To understand its cellular role, we performed RNAi and found that MINCR knockdown is associated with an impairment in cell cycle progression. Differential gene expression analysis after RNAi showed a significant enrichment of cell cycle genes among the genes down-regulated after MINCR knockdown. Interestingly, these genes are enriched in MYC binding sites in their promoters, suggesting that MINCR acts as a modulator of the MYC transcriptional program. Accordingly, MINCR knockdown was associated with a reduction in MYC binding to the promoters of selected cell cycle genes. Finally, we show that down-regulation of Aurora kinases A and B and chromatin licensing and DNA replication factor 1 may explain the reduction in cellular proliferation observed on MINCR knockdown. We, therefore, suggest that MINCR is a newly identified player in the MYC transcriptional network able to control the expression of cell cycle genes.


Assuntos
Linfoma de Burkitt/metabolismo , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Linfoma de Células B/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , RNA Longo não Codificante/metabolismo , Sequência de Bases , Sítios de Ligação , Ciclo Celular , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular , Cromatina/metabolismo , Perfilação da Expressão Gênica , Humanos , Hibridização in Situ Fluorescente , Dados de Sequência Molecular , Neoplasias/metabolismo , Regiões Promotoras Genéticas , RNA Interferente Pequeno/metabolismo , Homologia de Sequência do Ácido Nucleico
16.
Clin Oral Investig ; 22(1): 411-418, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28536781

RESUMO

BACKGROUND: The aim of this cross-sectional study was to evaluate the oral health of adult patients with newly diagnosed acute leukemia. METHODS: Patients with initially diagnosed acute myeloid (AML) or lymphocytic (ALL) leukemia and a matched healthy control (HC) group were included. The oral investigation comprised inspection of the oral mucosa; the decayed (D), missing (M), and filled (F) teeth (DMF-T) index; and a detailed periodontal status. Subgingival biofilm samples were analyzed (polymerase chain reaction) for the presence of selected potentially periodontal pathogenic bacteria. Statistical analysis was performed using Fisher's exact test, chi-squared test, and Mann-Whitney U test (significance level α = 5%). RESULTS: Thirty-nine patients with leukemia (AML 26, ALL 13) and 38 HCs were included. Oral mucosal findings were present in 62% of L compared to 0% of HC patients, whereby gingival hyperplasia was the most detected finding. Furthermore, a higher caries prevalence in leukemia patients was shown (D value 3.64 ± 3.98 vs. 0.72 ± 1.72, p < 0.01). The periodontal parameters were poorer in leukemia patients. No substantial differences in microbiological findings of selected bacteria were detected within L group and between L and HC patients. CONCLUSION: The high prevalence of oral diseases supports the demand of an early and consequent dental treatment of leukemia patients, especially considering subsequent therapy.


Assuntos
Leucemia Linfoide/complicações , Leucemia Mieloide Aguda/complicações , Doenças da Boca/epidemiologia , Saúde Bucal , Adulto , Biofilmes , Estudos de Casos e Controles , Estudos Transversais , Índice CPO , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice Periodontal , Reação em Cadeia da Polimerase , Prevalência , Estudos Prospectivos , Inquéritos e Questionários
17.
Int J Cancer ; 141(7): 1381-1388, 2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-28614910

RESUMO

TP53 is mutated in 20-25% of aggressive B-cell lymphoma (B-NHL). To date, no studies have addressed the impact of TP53 mutations in prospective clinical trial cohorts. To evaluate the impact of TP53 mutation to current risk models in aggressive B-NHL, we investigated TP53 gene mutations within the RICOVER-60 trial. Of 1,222 elderly patients (aged 61-80 years) enrolled in the study and randomized to six or eight cycles of CHOP-14 with or without Rituximab (NCT00052936), 265 patients were analyzed for TP53 mutations. TP53 mutations were demonstrated in 63 of 265 patients (23.8%). TP53 mutation was associated with higher LDH (65% vs. 37%; p < 0.001), higher international prognostic index-Scores (IPI 4/5 27% vs. 12%; p = 0.025) and B-symptoms (41% vs. 24%; p = 0.011). Patients with TP53 mutation were less likely to obtain a complete remission CR/CRu (CR unconfirmed) 61.9% (mut) vs. 79.7% (wt) (p = 0.007). TP53 mutations were associated with decreased event-free (EFS), progression-free (PFS) and overall survival (OS) (median observation time of 40.2 months): the 3 year EFS, PFS and OS were 42% (vs. 60%; p = 0.012), 42% (vs. 67.5%; p < 0.001) and 50% (vs. 76%; p < 0.001) for the TP53 mutation group. In a Cox proportional hazard analysis adjusting for IPI-factors and treatment arms, TP53 mutation was shown to be an independent predictor of EFS (HR 1.5), PFS (HR 2.0) and OS (HR 2.3; p < 0.001). TP53 mutations are independent predictors of survival in untreated patients with aggressive CD20+ lymphoma. TP53 mutations should be considered for risk models in DLBCL and strategies to improve outcome for patients with mutant TP53 must be developed.


Assuntos
Genes p53 , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/mortalidade , Mutação , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ciclofosfamida/administração & dosagem , Intervalo Livre de Doença , Doxorrubicina/administração & dosagem , Feminino , Humanos , L-Lactato Desidrogenase , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Prednisona/administração & dosagem , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Rituximab/administração & dosagem , Vincristina/administração & dosagem
18.
Oncology ; 93(4): 270-278, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28683465

RESUMO

BACKGROUND: ATP-binding cassette transport protein A3 (ABCA3) is expressed in non-small cell lung cancer (NSCLC). We hypothesize that high-level ABCA3 expression may have a negative prognostic impact in patients with NSCLC. METHODS: In 89 patients with NSCLC and curative intended surgery, we analyzed postoperative immunohistochemistry staining of primary tumors (anti-ABCA3) and clinicopathological parameters. We used a unidimensional four point score (FPS) system for intensity assessment and, furthermore, a combined bidimensional scoring of intensity and quantity resulting in the positive index (PI). RESULTS: Former or never-smokers were more likely to have intermediate or strong ABCA3 unidimensional expression (FPS) compared with current smokers (p < 0.01). Patients >65 years of age had a higher probability of intermediate/strong ABCA3 expression (FPS) than younger patients (p < 0.05). In PI measurement, there were no significant correlations between ABCA3 and clinicopathological parameters. Patients with high-level PI had a significantly worse disease-free survival as well as overall survival than patients with low-level PI (p < 0.05). CONCLUSIONS: High-level PI of ABCA3 in NSCLC showed poor disease-free and overall survival in this patient cohort, potentially indicating the relevance of ABCA3 in lung cancer. This observation needs to be validated in larger series.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Fenótipo , Adulto , Idoso , Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/terapia , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/terapia , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Estudos Retrospectivos , Taxa de Sobrevida , Análise Serial de Tecidos , Resultado do Tratamento , Células Tumorais Cultivadas
19.
Ann Hematol ; 96(6): 887-894, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28374162

RESUMO

Transfusion-dependent patients with low- or intermediate-1-risk myelodysplastic syndrome, <5% bone marrow (BM) blasts and isolated 5q-deletion received lenalidomide within the German MDS study group phase-II clinical trial LE-MON-5 (EudraCT:2008-001866-10) of the University of Duesseldorf, Germany. Cytogenetic monitoring was performed by chromosome banding analyses (CBA) of BM cells and fluorescence in situ hybridization (FISH) analyses of peripheral blood (PB) mononuclear CD34+ cells using extended probe panels. Out of 144 patients screened for study enrollment, 24% failed to meet inclusion criteria due to cytogenetic findings. Eighty-seven patients were followed with a median observation time of 30 months. Cytogenetic response detected by FISH and CBA in 74 and 66% of patients, respectively, was predictive for hematologic response as well as of high prognostic relevance. After 2 years, AML rate was 8% for all patients. Karyotype evolution was detected in 21 (FISH)-34% (CBA) of patients associated with significantly shorter AML-free survival. Disease progression was first detectable on the cytogenetic level on average 5-6 months before recurrence of transfusion dependence. Our data show for the first time in a prospective setting that a cytogenetic monitoring from the PB helps to early identify treatment failure and progressive disease in lenalidomide-treated patients to improve clinical management. TRIAL REGISTRATION: EudraCT:2008-001866-10.


Assuntos
Síndromes Mielodisplásicas/tratamento farmacológico , Talidomida/análogos & derivados , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Inibidores da Angiogênese/uso terapêutico , Antígenos CD34/sangue , Bandeamento Cromossômico , Deleção Cromossômica , Cromossomos Humanos Par 5/genética , Intervalo Livre de Doença , Feminino , Alemanha , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Lenalidomida , Leucemia Mieloide/diagnóstico , Leucemia Mieloide/genética , Leucócitos Mononucleares/metabolismo , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/genética , Prognóstico , Talidomida/uso terapêutico , Falha de Tratamento
20.
Acta Haematol ; 137(1): 51-54, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27923223

RESUMO

Pneumatosis intestinalis (PI), defined as intestinal intra- and extramural gas accumulation, is a rare radiographic finding in conditions of intestinal wall damage of varied etiology. Here, we report on a 56-year-old female with multiple myeloma who presented with undulating fever, fluctuating abdominal symptoms, and a distended abdomen 5 months after allogeneic hematopoietic stem cell transplantation (HSCT). Abdominal X-ray and CT scan documented PI with gas accumulation both in the intestinal and colonic bowel walls. Concurrently, thoracic CT revealed mediastinal and bihilar lymphadenopathy associated with bilateral pleural effusions. Microscopy of bronchoalveolar lavage fluid (BALF) revealed acid-fast bacilli, which were identified as Mycobacterium tuberculosis. Tuberculostatic treatment resulted in timely clinical improvement, a complete clearance of the radiological and clinical findings of PI, and the control of the tuberculosis (Tbc), determined by multiple negative BALF results. Taken together, PI occurred as the initial symptom of Tbc in an allogeneic stem cell recipient, achieving complete recovery by tuberculostatic treatment only.


Assuntos
Antituberculosos/uso terapêutico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Derrame Pleural/diagnóstico por imagem , Pneumatose Cistoide Intestinal/diagnóstico por imagem , Tuberculose Pulmonar/diagnóstico por imagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Líquido da Lavagem Broncoalveolar/microbiologia , Feminino , Humanos , Isoniazida/uso terapêutico , Pessoa de Meia-Idade , Mieloma Múltiplo/patologia , Mieloma Múltiplo/terapia , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/crescimento & desenvolvimento , Mycobacterium tuberculosis/isolamento & purificação , Derrame Pleural/tratamento farmacológico , Derrame Pleural/etiologia , Pneumatose Cistoide Intestinal/tratamento farmacológico , Pneumatose Cistoide Intestinal/etiologia , Rifampina/uso terapêutico , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/etiologia
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