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1.
Blood ; 135(3): 181-190, 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31697802

RESUMO

The genetic background of follicular lymphomas (FLs) diagnosed in advanced clinical stages III/IV, and which are frequently characterized by t(14;18), has been substantially unraveled. Molecular features, as exemplified in the clinicogenetic risk model m7FLIPI, are important tools in risk stratification. In contrast, little information is available concerning localized-stage FL (clinical stages I/II), which accounts for ∼20% of newly diagnosed FL in which the detection rate of t(14;18) is only ∼50%. To investigate the genetic background of localized-stage FL, patient cohorts with advanced-stage FL or localized-stage FL, uniformly treated within phase 3 trials of the German Low-Grade Lymphoma Study Group, were comparatively analyzed. Targeted gene expression (GE) profiling of 184 genes using nCounter technology was performed in 110 localized-stage and 556 advanced-stage FL patients. By penalized Cox regression, a prognostic GE signature could not be identified in patients with advanced-stage FL, consistent with results from global tests and univariate regression. In contrast, it was possible to define robust GE signatures discriminating localized-stage and advanced-stage FL (area under the curve, 0.98) by penalized logistic regression. Of note, 3% of samples harboring an "advanced-stage signature" in the localized-stage cohort exhibited inferior failure-free survival (hazard ratio [HR], 7.1; P = .0003). Likewise, in the advanced-stage cohort, 7% of samples with a "localized-stage signature" had prolonged failure-free survival (HR, 2.3; P = .017) and overall survival (HR, 3.4; P = .072). These data support the concept of a biological difference between localized-stage and advanced-stage FL that might contribute to the superior outcome of localized FL.

2.
Haematologica ; 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31601693

RESUMO

Oncogenic RAS provides crucial survival signaling for up to half of multiple myeloma cases, but has so far remained a clinically undruggable target. RAL is a member of the RAS superfamily of small GTPases and is considered to be a potential mediator of oncogenic RAS signaling. In primary multiple myeloma, we found RAL to be overexpressed in the vast majority of samples when compared with pre-malignant monoclonal gammopathy of undetermined significance or normal plasma cells. We analyzed the functional effects of RAL abrogation in myeloma cell lines and found that RAL is a critical mediator of survival. RNAi-mediated knockdown of RAL resulted in rapid induction of tumor cell death, an effect which was independent from signaling via mitogen-activated protein kinase, but appears to be partially dependent on Akt activity. Notably, RAL activation was not correlated with the presence of activating RAS mutations and remained unaffected by knockdown of oncogenic RAS. Furthermore, transcriptome analysis yielded distinct RNA expression signatures after knockdown of either RAS or RAL. Combining RAL depletion with clinically relevant anti-myeloma agents led to enhanced rates of cell death. Our data demonstrate that RAL promotes multiple myeloma cell survival independently of oncogenic RAS and, thus, this pathway represents a potential therapeutic target in its own right.

3.
Cell Death Dis ; 10(8): 611, 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31406107

RESUMO

The NEDD8-activating enzyme (NAE) inhibitor MLN4924 inhibits cullin-RING ubiquitin ligase complexes including the SKP1-cullin-F-box E3 ligase ßTrCP. MLN4924 therefore inhibits also the ßTrCP-dependent activation of the classical and the alternative NFĸB pathway. In this work, we found that a subgroup of multiple myeloma cell lines (e.g., RPMI-8226, MM.1S, KMS-12BM) and about half of the primary myeloma samples tested are sensitized to TNF-induced cell death by MLN4924. This correlated with MLN4924-mediated inhibition of TNF-induced activation of the classical NFκB pathway and reduced the efficacy of TNF-induced TNFR1 signaling complex formation. Interestingly, binding studies revealed a straightforward correlation between cell surface TNFR1 expression in multiple myeloma cell lines and their sensitivity for MLN4924/TNF-induced cell death. The cell surface expression levels of TNFR1 in the investigated MM cell lines largely correlated with TNFR1 mRNA expression. This suggests that the variable levels of cell surface expression of TNFR1 in myeloma cell lines are decisive for TNF/MLN4924 sensitivity. Indeed, introduction of TNFR1 into TNFR1-negative TNF/MLN4924-resistant KMS-11BM cells, was sufficient to sensitize this cell line for TNF/MLN4924-induced cell death. Thus, MLN4924 might be especially effective in myeloma patients with TNFR1+ myeloma cells and a TNFhigh tumor microenvironment.

4.
J Clin Exp Hematop ; 59(1): 1-16, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30918139

RESUMO

The microenvironment influences the behavior of follicular lymphoma (FL) but the specific roles of the immunomodulatory BTLA and TNFRSF14 (HVEM) are unknown. Therefore, we examined their immunohistochemical expression in the intrafollicular, interfollicular and total histological compartments in 106 FL cases (57M/49F; median age 57-years), and in nine relapsed-FL with transformation to DLBCL (tFL). BTLA expression pattern was of follicular T-helper cells (TFH) in the intrafollicular and of T-cells in the interfollicular compartments. The mantle zones were BTLA+ in 35.6% of the cases with similar distribution of IgD. TNFRSF14 expression pattern was of neoplastic B lymphocytes (centroblasts) and "tingible body macrophages". At diagnosis, the averages of total BTLA and TNFRSF14-positive cells were 19.2%±12.4STD (range, 0.6%-58.2%) and 46.7 cells/HPF (1-286.5), respectively. No differences were seen between low-grade vs. high-grade FL but tFL was characterized by low BTLA and high TNFRSF14 expression. High BTLA correlated with good overall survival (OS) (total-BTLA, Hazard Risk=0.479, P=0.022) and with high PD-1 and FOXP3+Tregs. High TNFRSF14 correlated with poor OS and progression-free survival (PFS) (total-TNFRSF14, HR=3.9 and 3.2, respectively, P<0.0001), with unfavorable clinical variables and higher risk of transformation (OR=5.3). Multivariate analysis including BTLA, TNFRSF14 and FLIPI showed that TNFRSF14 and FLIPI maintained prognostic value for OS and TNFRSF14 for PFS. In the GSE16131 FL series, high TNFRSF14 gene expression correlated with worse prognosis and GSEA showed that NFkB pathway was associated with the "High-TNFRSF14/dead-phenotype".In conclusion, the BTLA-TNFRSF14 immune modulation pathway seems to play a role in the pathobiology and prognosis of FL.


Assuntos
Linfoma Folicular/diagnóstico , Linfoma Difuso de Grandes Células B/diagnóstico , Receptores Imunológicos/metabolismo , Membro 14 de Receptores do Fator de Necrose Tumoral/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Linfócitos B/química , Linfócitos B/patologia , Transformação Celular Neoplásica , Feminino , Humanos , Fatores Imunológicos , Linfoma Folicular/mortalidade , Linfoma Difuso de Grandes Células B/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Análise de Sobrevida , Linfócitos T/química
6.
Leukemia ; 33(2): 447-456, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30026573

RESUMO

Despite an increasing number of approved therapies, multiple myeloma (MM) remains an incurable disease and only a small number of patients achieve prolonged disease control. Some genes have been linked with response to commonly used anti-MM compounds, including immunomodulators (IMiDs) and proteasome inhibitors (PIs). In this manuscript, we demonstrate an increased incidence of acquired proteasomal subunit mutations in relapsed MM compared to newly diagnosed disease, underpinning a potential role of point mutations in the clonal evolution of MM. Furthermore, we are first to present and functionally characterize four somatic PSMB5 mutations from primary MM cells identified in a patient under prolonged proteasome inhibition, with three of them affecting the PI-binding pocket S1. We confirm resistance induction through missense mutations not only to Bortezomib, but also, in variable extent, to the next-generation PIs Carfilzomib and Ixazomib. In addition, a negative impact on the proteasome activity is assessed, providing a potential explanation for later therapy-induced eradication of the affected tumor subclones in this patient.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/genética , Resistencia a Medicamentos Antineoplásicos/genética , Mieloma Múltiplo/genética , Mutação , Recidiva Local de Neoplasia/genética , Complexo de Endopeptidases do Proteassoma/genética , Biomarcadores Tumorais/metabolismo , Compostos de Boro/administração & dosagem , Bortezomib/administração & dosagem , Estudos de Coortes , Feminino , Seguimentos , Regulação Neoplásica da Expressão Gênica , Glicina/administração & dosagem , Glicina/análogos & derivados , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/patologia , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/patologia , Oligopeptídeos/administração & dosagem , Prognóstico , Complexo de Endopeptidases do Proteassoma/efeitos dos fármacos , Complexo de Endopeptidases do Proteassoma/metabolismo , Taxa de Sobrevida
7.
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
8.
Haematologica ; 103(1): 116-125, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29079592

RESUMO

Mantle cell lymphoma and other lymphoma subtypes often spread to the bone marrow, and stromal interactions mediated by focal adhesion kinase frequently enhance survival and drug resistance of the lymphoma cells. To study the role of focal adhesion kinase in mantle cell lymphoma, immunohistochemistry of primary cases and functional analysis of mantle cell lymphoma cell lines and primary mantle cell lymphoma cells co-cultured with bone marrow stromal cells (BMSC) using small molecule inhibitors and RNAi-based focal adhesion kinase silencing was performed. We showed that focal adhesion kinase is highly expressed in bone marrow infiltrates of mantle cell lymphoma and in mantle cell lymphoma cell lines. Stroma-mediated activation of focal adhesion kinase led to activation of multiple kinases (AKT, p42/44 and NF-κB), that are important for prosurvival and proliferation signaling. Interestingly, RNAi-based focal adhesion kinase silencing or inhibition with small molecule inhibitors (FAKi) resulted in blockage of targeted cell invasion and induced apoptosis by inactivation of multiple signaling cascades, including the classic and alternative NF-κB pathway. In addition, the combined treatment of ibrutinib and FAKi was highly synergistic, and ibrutinib resistance of mantle cell lymphoma could be overcome. These data demonstrate that focal adhesion kinase is important for stroma-mediated survival and drug resistance in mantle cell lymphoma, providing indications for a targeted therapeutic strategy.


Assuntos
Medula Óssea/metabolismo , Medula Óssea/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Proteína-Tirosina Quinases de Adesão Focal/genética , Linfoma de Célula do Manto/genética , Linfoma de Célula do Manto/patologia , Pirazóis/farmacologia , Pirimidinas/farmacologia , Microambiente Tumoral/genética , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Feminino , Quinase 1 de Adesão Focal/genética , Quinase 1 de Adesão Focal/metabolismo , Proteína-Tirosina Quinases de Adesão Focal/antagonistas & inibidores , Expressão Gênica , Humanos , Imuno-Histoquímica , Linfoma de Célula do Manto/tratamento farmacológico , Linfoma de Célula do Manto/metabolismo , Masculino , NF-kappa B/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Transdução de Sinais/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos
9.
Blood ; 131(2): 226-235, 2018 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-29122756

RESUMO

Follicular lymphoma (FL) is a clinically and molecularly highly heterogeneous disease, yet prognostication relies predominantly on clinical tools. We recently demonstrated that integration of mutation status of 7 genes, including EZH2 and MEF2B, improves risk stratification. We mined gene expression data to uncover genes that are differentially expressed in EZH2- and MEF2B-mutated cases. We focused on FOXP1 and assessed its protein expression by immunohistochemistry (IHC) in 763 tissue biopsies. For outcome correlation, a population-based training cohort of 142 patients with FL treated with rituximab, cyclophosphamide, vincristine, and prednisone, and a clinical trial validation cohort comprising 395 patients treated with cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) ± rituximab were used. We found FOXP1 to be significantly downregulated in both EZH2- and MEF2B-mutated cases. By IHC, 76 specimens in the training cohort (54%) had high FOXP1 expression (>10%), which was associated with reduced 5-year failure-free survival (FFS) rates (55% vs 70%). In the validation cohort, high FOXP1 expression status was observed in 248 patients (63%) and correlated with significantly shorter FFS in patients treated with R-CHOP (hazard ratio [HR], 1.95; P = .017) but not in patients treated with CHOP (HR, 1.15; P = .44). The impact of high FOXP1 expression on FFS in immunochemotherapy-treated patients was additional to the Follicular Lymphoma International Prognostic Index. High FOXP1 expression was associated with distinct molecular features such as TP53 mutations, expression of IRF4, and gene expression signatures reminiscent of dark zone germinal center or activated B cells. In summary, FOXP1 is a downstream phenotypic commonality of gene mutations and predicts outcome following rituximab-containing regimens.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Fatores de Transcrição Forkhead/genética , Regulação Neoplásica da Expressão Gênica , Linfoma Folicular/tratamento farmacológico , Proteínas Repressoras/genética , Rituximab/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ciclofosfamida/uso terapêutico , Doxorrubicina/uso terapêutico , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Fatores de Transcrição Forkhead/análise , Humanos , Linfoma Folicular/genética , Linfoma Folicular/patologia , Fatores de Transcrição MEF2/genética , Pessoa de Meia-Idade , Mutação , Prednisolona/uso terapêutico , Prednisona/uso terapêutico , Prognóstico , Proteínas Repressoras/análise , Resultado do Tratamento , Vincristina/uso terapêutico
10.
Br J Haematol ; 180(3): 391-394, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29193015

RESUMO

Predominantly diffuse t(14;18) negative follicular lymphoma (FL) with 1p36 deletion shows distinctive clinical, morphological and molecular features that distinguish it from classical FL. In order to investigate whether it possesses a unique mutation profile, we performed whole exome sequencing of six well-characterised cases. Our analysis showed that the mutational landscape of this subtype is largely distinct from classical FL. It appears to harbour several recurrent mutations, affecting STAT6, CREBBP and basal membrane protein genes with high frequency. Our data support the view that this FL subtype should be considered a separate entity from classical FL.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 1 , Exoma , Predisposição Genética para Doença , Linfoma Folicular/genética , Linfoma Folicular/patologia , Translocação Genética , Cromossomos Humanos Par 14 , Cromossomos Humanos Par 18 , Humanos , Mutação , Polimorfismo de Nucleotídeo Único , Sequenciamento Completo do Exoma
11.
Oncotarget ; 8(49): 85858-85867, 2017 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-29156762

RESUMO

Multiple Myeloma (MM) is an incurable hematological malignancy affecting millions of people worldwide. As in all tumor cells both glucose and more recently glutamine have been identified as important for MM cellular metabolism, however there is some dispute as to the role of glutamine in MM cell survival. Here we show that the small molecule inhibitor compound 968 effectively inhibits glutaminase and that this inhibition induces apoptosis in both human multiple myeloma cell lines (HMCLs) and primary patient material. The HMCL U266 which does not express MYC was insensitive to both glutamine removal and compound 968, but ectopic expression of MYC imparted sensitivity. Finally, we show that glutamine depletion is reflected by rapid loss of MYC protein which is independent of MYC transcription and post translational modifications. However, MYC loss is dependent on proteasomal activity, and this loss was paralleled by an equally rapid induction of apoptosis. These findings are in contrast to those of glucose depletion which largely affected rates of proliferation in HMCLs, but had no effects on either MYC expression or viability. Therefore, inhibition of glutaminolysis is effective at inducing apoptosis and thus serves as a possible therapeutic target in MM.

12.
Haematologica ; 101(11): 1380-1389, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27390358

RESUMO

MicroRNA are well-established players in post-transcriptional gene regulation. However, information on the effects of microRNA deregulation mainly relies on bioinformatic prediction of potential targets, whereas proof of the direct physical microRNA/target messenger RNA interaction is mostly lacking. Within the International Cancer Genome Consortium Project "Determining Molecular Mechanisms in Malignant Lymphoma by Sequencing", we performed miRnome sequencing from 16 Burkitt lymphomas, 19 diffuse large B-cell lymphomas, and 21 follicular lymphomas. Twenty-two miRNA separated Burkitt lymphomas from diffuse large B-cell lymphomas/follicular lymphomas, of which 13 have shown regulation by MYC. Moreover, we found expression of three hitherto unreported microRNA. Additionally, we detected recurrent mutations of hsa-miR-142 in diffuse large B-cell lymphomas and follicular lymphomas, and editing of the hsa-miR-376 cluster, providing evidence for microRNA editing in lymphomagenesis. To interrogate the direct physical interactions of microRNA with messenger RNA, we performed Argonaute-2 photoactivatable ribonucleoside-enhanced cross-linking and immunoprecipitation experiments. MicroRNA directly targeted 208 messsenger RNA in the Burkitt lymphomas and 328 messenger RNA in the non-Burkitt lymphoma models. This integrative analysis discovered several regulatory pathways of relevance in lymphomagenesis including Ras, PI3K-Akt and MAPK signaling pathways, also recurrently deregulated in lymphomas by mutations. Our dataset reveals that messenger RNA deregulation through microRNA is a highly relevant mechanism in lymphomagenesis.


Assuntos
Linfoma de Células B/genética , MicroRNAs/metabolismo , RNA Mensageiro/metabolismo , Análise de Sequência de RNA/métodos , Adolescente , Linfoma de Burkitt/genética , Criança , Pré-Escolar , Feminino , Perfilação da Expressão Gênica , Centro Germinativo , Humanos , Lactente , Recém-Nascido , Linfoma Folicular/genética , Linfoma Difuso de Grandes Células B/genética , Masculino , MicroRNAs/genética , Mutação , Edição de RNA
13.
Oncotarget ; 7(25): 38762-38774, 2016 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-27246973

RESUMO

Multiple myeloma (MM) is a plasma cell disorder that is characterized by a great genetic heterogeneity. Recent next generation sequencing studies revealed an accumulation of tumor-associated mutations in receptor tyrosine kinases (RTKs) which may also contribute to the activation of survival pathways in MM. To investigate the clinical role of RTK-mutations in MM, we deep-sequenced the coding DNA-sequence of EGFR, EPHA2, ERBB3, IGF1R, NTRK1 and NTRK2 which were previously found to be mutated in MM, in 75 uniformly treated MM patients of the "Deutsche Studiengruppe Multiples Myelom". Subsequently, we correlated the detected mutations with common cytogenetic alterations and clinical parameters. We identified 11 novel non-synonymous SNVs or rare patient-specific SNPs, not listed in the SNP databases 1000 genomes and dbSNP, in 10 primary MM cases. The mutations predominantly affected the tyrosine-kinase and ligand-binding domains and no correlation with cytogenetic parameters was found. Interestingly, however, patients with RTK-mutations, specifically those with rare patient-specific SNPs, showed a significantly lower overall, event-free and progression-free survival. This indicates that RTK SNVs and rare patient-specific RTK SNPs are of prognostic relevance and suggests that MM patients with RTK-mutations could potentially profit from treatment with RTK-inhibitors.


Assuntos
Mieloma Múltiplo/genética , Polimorfismo de Nucleotídeo Único , Receptores Proteína Tirosina Quinases/genética , Intervalo Livre de Doença , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Ligantes , Mieloma Múltiplo/terapia , Mutação , Prognóstico , Domínios Proteicos , Análise de Sequência de DNA , Resultado do Tratamento
15.
Endocrinology ; 156(11): 3895-908, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26305886

RESUMO

Adrenocortical carcinoma (ACC) is a rare malignancy that harbors a dismal prognosis in advanced stages. Mitotane is approved as an orphan drug for treatment of ACC and counteracts tumor growth and steroid hormone production. Despite serious adverse effects, mitotane has been clinically used for decades. Elucidation of its unknown molecular mechanism of action seems essential to develop better ACC therapies. Here, we set out to identify the molecular target of mitotane and altered downstream mechanisms by combining expression genomics and mass spectrometry technology in the NCI-H295 ACC model cell line. Pathway analyses of expression genomics data demonstrated activation of endoplasmic reticulum (ER) stress and profound alteration of lipid-related genes caused by mitotane treatment. ER stress marker CHOP was strongly induced and the two upstream ER stress signalling events XBP1-mRNA splicing and eukaryotic initiation factor 2 A (eIF2α) phosphorylation were activated by mitotane in NCI-H295 cells but to a much lesser extent in four nonsteroidogenic cell lines. Lipid mass spectrometry revealed mitotane-induced increase of free cholesterol, oxysterols, and fatty acids specifically in NCI-H295 cells as cause of ER stress. We demonstrate that mitotane is an inhibitor of sterol-O-acyl-transferase 1 (SOAT1) leading to accumulation of these toxic lipids. In ACC tissue samples we show variable SOAT1 expression correlating with the response to mitotane treatment. In conclusion, mitotane confers adrenal-specific cytotoxicity and down-regulates steroidogenesis by inhibition of SOAT1 leading to lipid-induced ER stress. Targeting of cancer-specific lipid metabolism opens new avenues for treatment of ACC and potentially other types of cancer.


Assuntos
Apoptose/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Mitotano/farmacologia , Esterol O-Aciltransferase/antagonistas & inibidores , Neoplasias do Córtex Suprarrenal/tratamento farmacológico , Neoplasias do Córtex Suprarrenal/genética , Neoplasias do Córtex Suprarrenal/metabolismo , Carcinoma Adrenocortical/tratamento farmacológico , Carcinoma Adrenocortical/genética , Carcinoma Adrenocortical/metabolismo , Antineoplásicos Hormonais/farmacologia , Antineoplásicos Hormonais/uso terapêutico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Intervalo Livre de Doença , Estresse do Retículo Endoplasmático/genética , Cromatografia Gasosa-Espectrometria de Massas , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Células HeLa , Células Hep G2 , Humanos , Immunoblotting , Imuno-Histoquímica , Lipídeos/análise , Mitotano/uso terapêutico , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Esterol O-Aciltransferase/genética , Esterol O-Aciltransferase/metabolismo , Fator de Transcrição CHOP/genética , Fator de Transcrição CHOP/metabolismo , Transcriptoma/efeitos dos fármacos
16.
Lancet Oncol ; 16(9): 1111-1122, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26256760

RESUMO

BACKGROUND: Follicular lymphoma is a clinically and genetically heterogeneous disease, but the prognostic value of somatic mutations has not been systematically assessed. We aimed to improve risk stratification of patients receiving first-line immunochemotherapy by integrating gene mutations into a prognostic model. METHODS: We did DNA deep sequencing to retrospectively analyse the mutation status of 74 genes in 151 follicular lymphoma biopsy specimens that were obtained from patients within 1 year before beginning immunochemotherapy consisting of rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP). These patients were recruited between May 4, 2000, and Oct 20, 2010, as part of a phase 3 trial (GLSG2000). Eligible patients had symptomatic, advanced stage follicular lymphoma and were previously untreated. The primary endpoints were failure-free survival (defined as less than a partial remission at the end of induction, relapse, progression, or death) and overall survival calculated from date of treatment initiation. Median follow-up was 7·7 years (IQR 5·5-9·3). Mutations and clinical factors were incorporated into a risk model for failure-free survival using multivariable L1-penalised Cox regression. We validated the risk model in an independent population-based cohort of 107 patients with symptomatic follicular lymphoma considered ineligible for curative irradiation. Pretreatment biopsies were taken between Feb 24, 2004, and Nov 24, 2009, within 1 year before beginning first-line immunochemotherapy consisting of rituximab, cyclophosphamide, vincristine, and prednisone (R-CVP). Median follow-up was 6·7 years (IQR 5·7-7·6). FINDINGS: We established a clinicogenetic risk model (termed m7-FLIPI) that included the mutation status of seven genes (EZH2, ARID1A, MEF2B, EP300, FOXO1, CREBBP, and CARD11), the Follicular Lymphoma International Prognostic Index (FLIPI), and Eastern Cooperative Oncology Group (ECOG) performance status. In the training cohort, m7-FLIPI defined a high-risk group (28%, 43/151) with 5-year failure-free survival of 38·29% (95% CI 25·31-57·95) versus 77·21% (95% CI 69·21-86·14) for the low-risk group (hazard ratio [HR] 4·14, 95% CI 2·47-6·93; p<0·0001; bootstrap-corrected HR 2·02), and outperformed a prognostic model of only gene mutations (HR 3·76, 95% CI 2·10-6·74; p<0·0001; bootstrap-corrected HR 1·57). The positive predictive value and negative predictive value for 5-year failure-free survival were 64% and 78%, respectively, with a C-index of 0·80 (95% CI 0·71-0·89). In the validation cohort, m7-FLIPI again defined a high-risk group (22%, 24/107) with 5-year failure-free survival of 25·00% (95% CI 12·50-49·99) versus 68·24% (58·84-79·15) in the low-risk group (HR 3·58, 95% CI 2·00-6·42; p<0.0001). The positive predictive value for 5-year failure-free survival was 72% and 68% for negative predictive value, with a C-index of 0·79 (95% CI 0·69-0·89). In the validation cohort, risk stratification by m7-FLIPI outperformed FLIPI alone (HR 2·18, 95% CI 1·21-3·92), and FLIPI combined with ECOG performance status (HR 2·03, 95% CI 1·12-3·67). INTERPRETATION: Integration of the mutational status of seven genes with clinical risk factors improves prognostication for patients with follicular lymphoma receiving first-line immunochemotherapy and is a promising approach to identify the subset at highest risk of treatment failure. FUNDING: Deutsche Krebshilfe, Terry Fox Research Institute.


Assuntos
Anticorpos Monoclonais Murinos/administração & dosagem , Imunoterapia , Linfoma Folicular/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Adulto , Idoso , Anticorpos Monoclonais Murinos/imunologia , Ciclofosfamida/administração & dosagem , Intervalo Livre de Doença , Doxorrubicina , Feminino , Humanos , Linfoma Folicular/genética , Linfoma Folicular/imunologia , Linfoma Folicular/patologia , Masculino , Pessoa de Meia-Idade , Mutação , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/imunologia , Recidiva Local de Neoplasia/patologia , Prednisona/administração & dosagem , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento , Vincristina/administração & dosagem
17.
Br J Haematol ; 169(1): 57-70, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25521164

RESUMO

Multiple myeloma (MM) is a plasma cell neoplasm that presents with a major biological and clinical heterogeneity. We here investigated the spectrum of clonal and subclonal mutations of DIS3, an active part of the exosome complex, that may play a role in the development or progression of MM. The whole coding sequence of DIS3 was subjected to deep sequencing in 81 uniformly-treated MM patients and 12 MM cell lines and the overall occurrence of DIS3 mutations as well as the presence of DIS3 mutations in minor and major subclones were correlated with cytogenetic alterations and clinical parameters. Our study identified DIS3 mutations in 9/81 patients that were associated with 13q14 deletions and IGH translocations on the cytogenetic level. Specifically, we detected seven novel somatic DIS3 single nucleotide variants (SNVs) and defined three hot spot mutations within the RNB domain. Lastly, we found a trend towards a shorter median overall survival for patients with DIS3 mutations, and patients carrying DIS3 mutations in minor subclones of their tumours showed a significantly worse response to therapy compared to patients with DIS3 mutations in the major subclone.


Assuntos
Cromossomos Humanos Par 13/genética , Complexo Multienzimático de Ribonucleases do Exossomo/genética , Mieloma Múltiplo/genética , Mutação , Proteínas de Neoplasias/genética , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Linhagem Celular Tumoral , Intervalo Livre de Doença , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/mortalidade , Taxa de Sobrevida
18.
Blood ; 123(7): 1051-4, 2014 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-24357726

RESUMO

Transformation of follicular lymphoma (FL) to a more aggressive disease is associated with rapid progression and death. Existing molecular markers for transformation are few and their clinical impact is limited. Here, we report on a whole-genome study of DNA copy numbers and gene expression profiles in serial FL biopsies. We identified 698 genes with high correlation between gene expression and copy number, and the molecular network most enriched for these cis-associated genes. This network includes 14 cis-associated genes directly related to the nuclear factor κB (NF-κB) pathway. For each of these 14 genes, the correlated NF-κB target genes were identified and corresponding expression scores were defined. The scores for 6 of the cis-associated NFκB pathway genes (BTK, IGBP1, IRAK1, ROCK1, TMED7-TICAM2, and TRIM37) were significantly associated with transformation. The results suggest that genes regulating B-cell survival and activation are involved in transformation of FL.


Assuntos
Transformação Celular Neoplásica/genética , Linfoma Folicular/genética , Transcriptoma , Dosagem de Genes , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Linfoma Folicular/patologia , Análise de Sequência com Séries de Oligonucleotídeos , Prognóstico , Integração de Sistemas
19.
PLoS One ; 8(9): e73959, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24066089

RESUMO

Adrenocortical tumors consist of benign adenomas and highly malignant carcinomas with a still incompletely understood pathogenesis. A total of 46 adrenocortical tumors (24 adenomas and 22 carcinomas) were investigated aiming to identify novel genes involved in adrenocortical tumorigenesis. High-resolution single nucleotide polymorphism arrays (Affymetrix) were used to detect copy number alterations (CNAs) and copy neutral losses of heterozygosity (cnLOH). Genomic clustering showed good separation between adenomas and carcinomas, with best partition including only chromosome 5, which was highly amplified in 17/22 malignant tumors. The malignant tumors had more relevant genomic aberrations than benign tumors, such as a higher median number of recurrent CNA (2631 vs 94), CNAs >100 Kb (62.5 vs 7) and CN losses (72.5 vs 5.5), and a higher percentage of samples with cnLOH (91% vs 29%). Within the carcinoma cohort, a precise genetic pattern (i.e. large gains at chr 5, 7, 12, and 19, and losses at chr 1, 2, 13, 17, and 22) was associated with a better prognosis (overall survival: 72.2 vs 35.4 months, P=0.063). Interestingly, >70% of gains frequent in benign were also present in malignant tumors. Notch signaling was the most frequently involved pathway in both tumor entities. Finally, a CN gain at imprinted "IGF2" locus chr 11p15.5 appeared to be an early alteration in a multi-step tumor progression, followed by the loss of one or two alleles, associated with increased IGF2 expression, only in carcinomas. Our study serves as database for the identification of genes and pathways, such as Notch signaling, which could be involved in the pathogenesis of adrenocortical tumors. Using these data, we postulate an adenoma-carcinoma sequence for these tumors.


Assuntos
Neoplasias do Córtex Suprarrenal/genética , Polimorfismo de Nucleotídeo Único/genética , Adolescente , Adulto , Idoso , Feminino , Humanos , Hibridização in Situ Fluorescente , Perda de Heterozigosidade/genética , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , Adulto Jovem
20.
PLoS Genet ; 9(8): e1003726, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23966881

RESUMO

p53 protects us from cancer by transcriptionally regulating tumor suppressive programs designed to either prevent the development or clonal expansion of malignant cells. How p53 selects target genes in the genome in a context- and tissue-specific manner remains largely obscure. There is growing evidence that the ability of p53 to bind DNA in a cooperative manner prominently influences target gene selection with activation of the apoptosis program being completely dependent on DNA binding cooperativity. Here, we used ChIP-seq to comprehensively profile the cistrome of p53 mutants with reduced or increased cooperativity. The analysis highlighted a particular relevance of cooperativity for extending the p53 cistrome to non-canonical binding sequences characterized by deletions, spacer insertions and base mismatches. Furthermore, it revealed a striking functional separation of the cistrome on the basis of cooperativity; with low cooperativity genes being significantly enriched for cell cycle and high cooperativity genes for apoptotic functions. Importantly, expression of high but not low cooperativity genes was correlated with superior survival in breast cancer patients. Interestingly, in contrast to most p53-activated genes, p53-repressed genes did not commonly contain p53 binding elements. Nevertheless, both the degree of gene activation and repression were cooperativity-dependent, suggesting that p53-mediated gene repression is largely indirect and mediated by cooperativity-dependently transactivated gene products such as CDKN1A, E2F7 and non-coding RNAs. Since both activation of apoptosis genes with non-canonical response elements and repression of pro-survival genes are crucial for p53's apoptotic activity, the cistrome analysis comprehensively explains why p53-induced apoptosis, but not cell cycle arrest, strongly depends on the intermolecular cooperation of p53 molecules as a possible safeguard mechanism protecting from accidental cell killing.


Assuntos
Apoptose/genética , Pontos de Checagem do Ciclo Celular/genética , Neoplasias/genética , Proteína Supressora de Tumor p53/genética , Sequência de Bases , Sítios de Ligação/genética , Divisão Celular , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Dano ao DNA/genética , Fator de Transcrição E2F7/genética , Fator de Transcrição E2F7/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias/metabolismo , Ligação Proteica/genética , RNA não Traduzido/genética , RNA não Traduzido/metabolismo , Ativação Transcricional , Proteína Supressora de Tumor p53/metabolismo
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