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1.
Proc Natl Acad Sci U S A ; 117(11): 6092-6102, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32127472

RESUMO

The KLHL14 gene acquires frequent inactivating mutations in mature B cell malignancies, especially in the MYD88L265P, CD79B mutant (MCD) genetic subtype of diffuse large B cell lymphoma (DLBCL), which relies on B cell receptor (BCR) signaling for survival. However, the pathogenic role of KLHL14 in DLBCL and its molecular function are largely unknown. Here, we report that KLHL14 is in close proximity to the BCR in the endoplasmic reticulum of MCD cell line models and promotes the turnover of immature glycoforms of BCR subunits, reducing total cellular BCR levels. Loss of KLHL14 confers relative resistance to the Bruton tyrosine kinase (BTK) inhibitor ibrutinib and promotes assembly of the MYD88-TLR9-BCR (My-T-BCR) supercomplex, which initiates prosurvival NF-κB activation. Consequently, KLHL14 inactivation allows MCD cells to maintain NF-κB signaling in the presence of ibrutinib. These findings reinforce the central role of My-T-BCR-dependent NF-κB signaling in MCD DLBCL and suggest that the genetic status of KLHL14 should be considered in clinical trials testing inhibitors of BTK and BCR signaling mediators in DLBCL.

2.
Comp Med ; 70(1): 56-66, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31810502

RESUMO

Zoonotic monkey B virus (Macacine alphaherpesvirus 1; BV) infections are extremely serious and usually fatal. Drugs currently used for treatment were developed for the treatment of herpes simplex virus but are less effective against BV. Effective suppression of viral replication in the skin could prevent the virus from invading the nervous system. To test this hypothesis, the efficacy of topical administration of several drugs against lethal BV infection was evaluated in female BALB/c mice that were infected by scarification. Drugs were then applied to the site of inoculation. As 3% preparations, most drugs were only minimally effective or ineffective. In contrast, ganciclovir and cidofovir were very effective. The ED50 for cidofovir was 0.007%, compared with 1.1% for ganciclovir. At 0.5%, cidofovir protected against both death and neurologic signs, whereas 5% ganciclovir only protected against death but not neurologic involvement. All genotypes of BV were equally susceptible to cidofovir and ganciclovir. For maximal effectiveness, treatment with both cidofovir and ganciclovir had to be initiated within 8 h of infection. Cidofovir was completely protective when administered only on the day of infection, whereas a minimum of 5 d of treatment was required for maximal ganciclovir efficacy. These studies showed that topical cidofovir treatment started soon after BV exposure was very effective in preventing BV from invading the nervous system, whereas ganciclovir treatment was only partially effective. In addition, cidofovir was protective against a ganciclovir-resistant BV mutant, whereas ganciclovir was not. These studies showed that topical cidofovir treatment started soon after BV exposure is more effective than ganciclovir in preventing BV from invading the CNS.

3.
Methods Mol Biol ; 2055: 649-678, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31502173

RESUMO

In recent years, cancer immunotherapy has emerged as a highly promising approach to treat patients with cancer, as the patient's own immune system is harnessed to attack cancer cells. However, the application of these approaches is still limited to a minority of patients with cancer and it is difficult to predict which patients will derive the greatest clinical benefit.One of the challenges faced by the biomedical community in the search of more effective biomarkers is the fact that translational research efforts involve collecting and accessing data at many different levels: from the type of material examined (e.g., cell line, animal models, clinical samples) to multiple data type (e.g., pharmacodynamic markers, genetic sequencing data) to the scale of a study (e.g., small preclinical study, moderate retrospective study on stored specimen sets, clinical trials with large cohorts).This chapter reviews several publicly available bioinformatics tools and data resources for high throughput molecular analyses applied to a range of data types, including those generated from microarray, whole-exome sequencing (WES), RNA-seq, DNA copy number, and DNA methylation assays, that are extensively used for integrative multidimensional data analysis and visualization.

4.
Onco Targets Ther ; 12: 6407-6438, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31496742

RESUMO

Purpose: Percutaneous ablation techniques, including microwave ablation (MWA) and radiofrequency ablation (RFA), have become important minimally invasive treatment options for liver cancer. This systematic review compared MWA with RFA for treatment of liver cancer. Methods: The systematic review and meta-analysis followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A systematic search of MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials was conducted for randomized and observational studies published from 2006 onwards. A random-effects model was used for meta-analyses and local tumor progression (LTP), technique efficacy, overall survival (OS), disease-free survival (DFS), intrahepatic de novo lesions (IDL), extrahepatic metastases (EHM), length of stay (LOS), and complications were analyzed. Subgroup and sensitivity analyses were also conducted. Results: Of 1379 studies identified, 28 randomized and observational studies met inclusion criteria. The main analysis demonstrated that LTP was significantly reduced by 30% with MWA versus RFA (RR=0.70; P=0.02) (all studies) and by 45% with MWA versus RFA (RR=0.55; P=0.007) (randomized studies only). There were no significant differences between MWA and RFA for other efficacy and safety outcomes. Higher frequency (2450 MHz) and larger tumor size (≥2.5 cm) are amongst variables that may be associated with improved outcomes for MWA. Sensitivity analyses were generally congruent with the main results. Conclusion: MWA is at least as safe and effective as RFA for treating liver cancer and demonstrated significantly reduced LTP rates. Future studies should assess time and costs associated with these two treatment modalities.

5.
Bioorg Med Chem ; 27(15): 3209-3217, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31221610

RESUMO

Despite the growing global crisis caused by antimicrobial drug resistance among pathogenic bacteria, the number of new antibiotics, especially new chemical class of antibiotics under development is insufficient to tackle the problem. Our review focuses on an emerging class of antibacterial therapeutic agents that holds a completely novel mechanism of action, namely, inhibition of bacterial DNA polymerase IIIC. The recent entry of this new class into human trials may herald the introduction of novel drugs whose novel molecular target precludes cross-resistance with existing antibiotic classes. This review therefore examines the evolution of DNA pol IIIC inhibitors from the discovery of 6-(p-hydroxyphenylazo)uracil (HPUra) in the 1960s to the development of current first-in-class N7-substituted guanine drug candidate ACX-362E, now under clinical development for the treatment of Clostridioides difficile infection.

6.
World J Surg Oncol ; 17(1): 98, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31182102

RESUMO

BACKGROUND: Hepatic resection (HR) is the gold standard liver cancer treatment, but few patients are eligible due to comorbidities or tumor location. Microwave ablation (MWA) is an important complementary liver cancer treatment to HR. This systematic review compared MWA with HR for liver cancer treatment. METHODS: A systematic search of MEDLINE, EMBASE, and CENTRAL was conducted for randomized and observational studies published from 2006 onwards. The primary outcome was local tumor recurrence (LTR), and a random effects model was used for meta-analyses. RESULTS: Of the 1845 studies identified, 1 randomized and 15 observational studies met the inclusion criteria. LTR was significantly increased with MWA versus HR (risk ratio (RR) = 2.49; P = 0.016). In secondary measures, HR provided significantly higher 3- and 5-year overall survival (RR = 0.94; P = 0.03 and RR = 0.88; P = 0.01, respectively) and 3-year disease-free survival (RR = 0.78; P = 0.009). MWA exhibited significantly shorter length of stay (weighted mean difference (WMD) = - 6.16 days; P < 0.001) and operative time (WMD = - 58.69 min; P < 0.001), less intraoperative blood loss (WMD = - 189.09 mL; P = 0.006), and fewer complications than HR (RR = 0.31; P < 0.001). When MWA was combined with HR and compared with either modality alone, complications and blood loss were significantly lower with the combination treatment; however, there were no differences in other outcomes. Subgroup and sensitivity analyses were generally aligned with the main results. CONCLUSIONS: MWA can be an effective and safe alternative to HR in patients/tumors that are not amenable to resection. More randomized and economic studies should be performed that compare the two treatments, especially to determine the target population that benefits most from MWA.


Assuntos
Carcinoma Hepatocelular/mortalidade , Ablação por Cateter/mortalidade , Hepatectomia/mortalidade , Neoplasias Hepáticas/mortalidade , Micro-Ondas , Carcinoma Hepatocelular/secundário , Carcinoma Hepatocelular/cirurgia , Humanos , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/cirurgia , Taxa de Sobrevida , Resultado do Tratamento
7.
Blood ; 133(12): 1313-1324, 2019 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-30617194

RESUMO

Although generally curable with intensive chemotherapy in resource-rich settings, Burkitt lymphoma (BL) remains a deadly disease in older patients and in sub-Saharan Africa. Epstein-Barr virus (EBV) positivity is a feature in more than 90% of cases in malaria-endemic regions, and up to 30% elsewhere. However, the molecular features of BL have not been comprehensively evaluated when taking into account tumor EBV status or geographic origin. Through an integrative analysis of whole-genome and transcriptome data, we show a striking genome-wide increase in aberrant somatic hypermutation in EBV-positive tumors, supporting a link between EBV and activation-induced cytidine deaminase (AICDA) activity. In addition to identifying novel candidate BL genes such as SIN3A, USP7, and CHD8, we demonstrate that EBV-positive tumors had significantly fewer driver mutations, especially among genes with roles in apoptosis. We also found immunoglobulin variable region genes that were disproportionally used to encode clonal B-cell receptors (BCRs) in the tumors. These include IGHV4-34, known to produce autoreactive antibodies, and IGKV3-20, a feature described in other B-cell malignancies but not yet in BL. Our results suggest that tumor EBV status defines a specific BL phenotype irrespective of geographic origin, with particular molecular properties and distinct pathogenic mechanisms. The novel mutation patterns identified here imply rational use of DNA-damaging chemotherapy in some patients with BL and targeted agents such as the CDK4/6 inhibitor palbociclib in others, whereas the importance of BCR signaling in BL strengthens the potential benefit of inhibitors for PI3K, Syk, and Src family kinases among these patients.


Assuntos
Biomarcadores Tumorais/genética , Linfoma de Burkitt/genética , Infecções por Vírus Epstein-Barr/complicações , Genes de Imunoglobulinas , Genoma Humano , Mutação , Transcriptoma , Adolescente , Adulto , Linfoma de Burkitt/patologia , Linfoma de Burkitt/virologia , Criança , Pré-Escolar , Estudos de Coortes , Citidina Desaminase/genética , Infecções por Vírus Epstein-Barr/genética , Infecções por Vírus Epstein-Barr/virologia , Feminino , Seguimentos , Herpesvirus Humano 4/isolamento & purificação , Humanos , Lactente , Recém-Nascido , Masculino , Fenótipo , Prognóstico , Adulto Jovem
8.
Artigo em Inglês | MEDLINE | ID: mdl-30455241

RESUMO

Clostridium difficile is a potentially lethal gut pathogen that causes nosocomial and community-acquired infections. Limited treatment options and reports of reduced susceptibility to current treatment emphasize the necessity for novel antimicrobials. The DNA polymerase of Gram-positive organisms is an attractive target for the development of antimicrobials. ACX-362E [N 2-(3,4-dichlorobenzyl)-7-(2-[1-morpholinyl]ethyl)guanine; MorE-DCBG] is a DNA polymerase inhibitor in preclinical development as a novel therapeutic against C. difficile infection. This synthetic purine shows preferential activity against C. difficile PolC over those of other organisms in vitro and is effective in an animal model of C. difficile infection. In this study, we have determined its efficacy against a large collection of clinical isolates. At concentrations below the MIC, the presumed slowing (or stalling) of replication forks due to ACX-362E leads to a growth defect. We have determined the transcriptional response of C. difficile to replication inhibition and observed an overrepresentation of upregulated genes near the origin of replication in the presence of PolC inhibitors, but not when cells were subjected to subinhibitory concentrations of other antibiotics. This phenomenon can be explained by a gene dosage shift, as we observed a concomitant increase in the ratio between origin-proximal and terminus-proximal gene copy number upon exposure to PolC inhibitors. Moreover, we show that certain genes differentially regulated under PolC inhibition are controlled by the origin-proximal general stress response regulator sigma factor B. Together, these data suggest that genome location both directly and indirectly determines the transcriptional response to replication inhibition in C. difficile.


Assuntos
Proteínas de Bactérias/genética , Clostridium difficile/efeitos dos fármacos , Dosagem de Genes/genética , Dosagem de Genes/fisiologia , Regulação Bacteriana da Expressão Gênica/genética , Testes de Sensibilidade Microbiana , Inibidores da Síntese de Ácido Nucleico/farmacologia , Fator sigma/genética , Fator sigma/metabolismo
9.
Sci Rep ; 8(1): 17580, 2018 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-30498241

RESUMO

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

10.
Sci Rep ; 8(1): 14529, 2018 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-30266987

RESUMO

Dual antiplatelet therapy with aspirin and an adenosine diphosphate (ADP) P2Y12 receptor antagonist reduces ischemic events in patients with acute coronary syndrome. Previous evidence from our group, obtained in a preclinical model of recurrent platelet-mediated thrombosis, demonstrated that GLS-409, a diadenosine tetraphosphate derivative that inhibits both P2Y1 and P2Y12 ADP receptors, may be a novel and promising antiplatelet drug candidate. However, the salutary antiplatelet effects of GLS-409 were accompanied by a trend toward an unfavorable increase in bleeding. The goals of this study were to: 1) provide proof-of-concept that the efficacy of GLS-409 may be maintained at lower dose(s), not accompanied by an increased propensity to bleeding; and 2) establish the extent and kinetics of the reversibility of human platelet inhibition by the agent. Lower doses of GLS-409 were identified that inhibited in vivo recurrent coronary thrombosis with no increase in bleeding time. Human platelet inhibition by GLS-409 was reversible, with rapid recovery of platelet reactivity to ADP, as measured by platelet surface activated GPIIb-IIIa and platelet surface P-selectin. These data support the concept that GLS-409 warrants further, larger-scale investigation as a novel, potential therapy in acute coronary syndromes.


Assuntos
Trombose Coronária/veterinária , Fosfatos de Dinucleosídeos/uso terapêutico , Doenças do Cão/tratamento farmacológico , Ativação Plaquetária/efeitos dos fármacos , Antagonistas do Receptor Purinérgico P2Y/uso terapêutico , Animais , Trombose Coronária/tratamento farmacológico , Trombose Coronária/metabolismo , Doenças do Cão/metabolismo , Cães , Feminino , Humanos , Inibidores da Agregação de Plaquetas/uso terapêutico , Receptores Purinérgicos P2Y1/metabolismo , Receptores Purinérgicos P2Y12/metabolismo
11.
Blood ; 132(22): 2401-2405, 2018 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-30257882

RESUMO

Primary mediastinal large B-cell lymphoma (PMBCL) is recognized as a distinct entity in the World Health Organization classification. Currently, the diagnosis relies on consensus of histopathology, clinical variables, and presentation, giving rise to diagnostic inaccuracy in routine practice. Previous studies have demonstrated that PMBCL can be distinguished from subtypes of diffuse large B-cell lymphoma (DLBCL) based on gene expression signatures. However, requirement of fresh-frozen biopsy material has precluded the transfer of gene expression-based assays to the clinic. Here, we developed a robust and accurate molecular classification assay (Lymph3Cx) for the distinction of PMBCL from DLBCL subtypes based on gene expression measurements in formalin-fixed, paraffin-embedded tissue. A probabilistic model accounting for classification error, comprising 58 gene features, was trained on 68 cases of PMBCL and DLBCL. Performance of the model was subsequently evaluated in an independent validation cohort of 158 cases and showed high agreement of the Lymph3Cx molecular classification with the clinicopathological diagnosis of an expert panel (frank misclassification rate, 3.8%). Furthermore, we demonstrate reproducibility of the assay with 100% concordance of subtype assignments at 2 independent laboratories. Future studies will determine Lymph3Cx's utility for routine diagnostic purposes and therapeutic decision making.


Assuntos
Perfilação da Expressão Gênica , Linfoma Difuso de Grandes Células B/diagnóstico , Linfoma não Hodgkin/diagnóstico , Neoplasias do Mediastino/diagnóstico , Estudos de Coortes , Regulação Neoplásica da Expressão Gênica , Humanos , Linfoma Difuso de Grandes Células B/classificação , Linfoma Difuso de Grandes Células B/genética , Linfoma não Hodgkin/classificação , Linfoma não Hodgkin/genética , Neoplasias do Mediastino/classificação , Neoplasias do Mediastino/genética , Mediastino/patologia , Inclusão em Parafina
13.
Cancer Cell ; 34(2): 286-297.e10, 2018 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-30057145

RESUMO

Adult T cell leukemia/lymphoma (ATLL) is a frequently incurable disease associated with the human lymphotropic virus type I (HTLV-I). RNAi screening of ATLL lines revealed that their proliferation depends on BATF3 and IRF4, which cooperatively drive ATLL-specific gene expression. HBZ, the only HTLV-I encoded transcription factor that is expressed in all ATLL cases, binds to an ATLL-specific BATF3 super-enhancer and thereby regulates the expression of BATF3 and its downstream targets, including MYC. Inhibitors of bromodomain-and-extra-terminal-domain (BET) chromatin proteins collapsed the transcriptional network directed by HBZ and BATF3, and were consequently toxic for ATLL cell lines, patient samples, and xenografts. Our study demonstrates that the HTLV-I oncogenic retrovirus exploits a regulatory module that can be attacked therapeutically with BET inhibitors.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/genética , Redes Reguladoras de Genes , Vírus Linfotrópico T Tipo 1 Humano/fisiologia , Fatores Reguladores de Interferon/genética , Leucemia-Linfoma de Células T do Adulto/genética , Animais , Fatores de Transcrição de Zíper de Leucina Básica/fisiologia , Linhagem Celular Tumoral , Genes myc , Humanos , Camundongos , Proteínas/antagonistas & inibidores , Proteínas dos Retroviridae/fisiologia
14.
Nature ; 560(7718): 387-391, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29925955

RESUMO

B cell receptor (BCR) signalling has emerged as a therapeutic target in B cell lymphomas, but inhibiting this pathway in diffuse large B cell lymphoma (DLBCL) has benefited only a subset of patients1. Gene expression profiling identified two major subtypes of DLBCL, known as germinal centre B cell-like and activated B cell-like (ABC)2,3, that show poor outcomes after immunochemotherapy in ABC. Autoantigens drive BCR-dependent activation of NF-κB in ABC DLBCL through a kinase signalling cascade of SYK, BTK and PKCß to promote the assembly of the CARD11-BCL10-MALT1 adaptor complex, which recruits and activates IκB kinase4-6. Genome sequencing revealed gain-of-function mutations that target the CD79A and CD79B BCR subunits and the Toll-like receptor signalling adaptor MYD885,7, with MYD88(L265P) being the most prevalent isoform. In a clinical trial, the BTK inhibitor ibrutinib produced responses in 37% of cases of ABC1. The most striking response rate (80%) was observed in tumours with both CD79B and MYD88(L265P) mutations, but how these mutations cooperate to promote dependence on BCR signalling remains unclear. Here we used genome-wide CRISPR-Cas9 screening and functional proteomics to determine the molecular basis of exceptional clinical responses to ibrutinib. We discovered a new mode of oncogenic BCR signalling in ibrutinib-responsive cell lines and biopsies, coordinated by a multiprotein supercomplex formed by MYD88, TLR9 and the BCR (hereafter termed the My-T-BCR supercomplex). The My-T-BCR supercomplex co-localizes with mTOR on endolysosomes, where it drives pro-survival NF-κB and mTOR signalling. Inhibitors of BCR and mTOR signalling cooperatively decreased the formation and function of the My-T-BCR supercomplex, providing mechanistic insight into their synergistic toxicity for My-T-BCR+ DLBCL cells. My-T-BCR supercomplexes characterized ibrutinib-responsive malignancies and distinguished ibrutinib responders from non-responders. Our data provide a framework for the rational design of oncogenic signalling inhibitors in molecularly defined subsets of DLBCL.


Assuntos
Carcinogênese , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/patologia , Complexos Multiproteicos/metabolismo , Transdução de Sinais , Animais , Biópsia , Sistemas CRISPR-Cas/genética , Carcinogênese/genética , Desenho de Drogas , Feminino , Humanos , Linfoma Difuso de Grandes Células B/genética , Camundongos , Complexos Multiproteicos/química , Mutação , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/metabolismo , Proteômica , Pirazóis/farmacologia , Pirazóis/uso terapêutico , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Receptores de Antígenos de Linfócitos B/antagonistas & inibidores , Receptores de Antígenos de Linfócitos B/genética , Receptores de Antígenos de Linfócitos B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/metabolismo , Receptor Toll-Like 9/genética , Receptor Toll-Like 9/metabolismo , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Blood ; 132(4): 413-422, 2018 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-29769262

RESUMO

Mantle cell lymphoma (MCL) is an aggressive B-cell malignancy, but some patients have a very indolent evolution. This heterogeneous course is related, in part, to the different biological characteristics of conventional MCL (cMCL) and the distinct subgroup of leukemic nonnodal MCL (nnMCL). Robust criteria to distinguish these MCL subtypes and additional biological parameters that influence their evolution are not well defined. We describe a novel molecular assay that reliably distinguishes cMCL and nnMCL using blood samples. We trained a 16-gene assay (L-MCL16 assay) on the NanoString platform using 19 purified leukemic samples. The locked assay was applied to an independent cohort of 70 MCL patients with leukemic presentation. The assay assigned 37% of cases to nnMCL and 56% to cMCL. nnMCL and cMCL differed in nodal presentation, lactate dehydrogenase, immunoglobulin heavy chain gene mutational status, management options, genomic complexity, and CDKN2A/ATM deletions, but the proportion with 17p/TP53 aberrations was similar in both subgroups. Sequential samples showed that assay prediction was stable over time. nnMCL had a better overall survival (OS) than cMCL (3-year OS 92% vs 69%; P = .006) from the time of diagnosis and longer time to first treatment. Genomic complexity and TP53/CDKN2A aberrations predicted for shorter OS in the entire series and cMCL, whereas only genomic complexity was associated with shorter time to first treatment and OS in nnMCL. In conclusion, the newly developed assay robustly recognizes the 2 molecular subtypes of MCL in leukemic samples. Its combination with genetic alterations improves the prognostic evaluation and may provide useful biological information for management decisions.


Assuntos
Biomarcadores Tumorais/genética , Leucemia/genética , Leucemia/patologia , Linfoma de Célula do Manto/genética , Linfoma de Célula do Manto/patologia , Mutação , Estudos de Coortes , Feminino , Perfilação da Expressão Gênica , Genômica , Humanos , Leucemia/classificação , Linfoma de Célula do Manto/classificação , Masculino , Prognóstico , Taxa de Sobrevida
16.
N Engl J Med ; 378(15): 1396-1407, 2018 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-29641966

RESUMO

BACKGROUND: Diffuse large B-cell lymphomas (DLBCLs) are phenotypically and genetically heterogeneous. Gene-expression profiling has identified subgroups of DLBCL (activated B-cell-like [ABC], germinal-center B-cell-like [GCB], and unclassified) according to cell of origin that are associated with a differential response to chemotherapy and targeted agents. We sought to extend these findings by identifying genetic subtypes of DLBCL based on shared genomic abnormalities and to uncover therapeutic vulnerabilities based on tumor genetics. METHODS: We studied 574 DLBCL biopsy samples using exome and transcriptome sequencing, array-based DNA copy-number analysis, and targeted amplicon resequencing of 372 genes to identify genes with recurrent aberrations. We developed and implemented an algorithm to discover genetic subtypes based on the co-occurrence of genetic alterations. RESULTS: We identified four prominent genetic subtypes in DLBCL, termed MCD (based on the co-occurrence of MYD88L265P and CD79B mutations), BN2 (based on BCL6 fusions and NOTCH2 mutations), N1 (based on NOTCH1 mutations), and EZB (based on EZH2 mutations and BCL2 translocations). Genetic aberrations in multiple genes distinguished each genetic subtype from other DLBCLs. These subtypes differed phenotypically, as judged by differences in gene-expression signatures and responses to immunochemotherapy, with favorable survival in the BN2 and EZB subtypes and inferior outcomes in the MCD and N1 subtypes. Analysis of genetic pathways suggested that MCD and BN2 DLBCLs rely on "chronic active" B-cell receptor signaling that is amenable to therapeutic inhibition. CONCLUSIONS: We uncovered genetic subtypes of DLBCL with distinct genotypic, epigenetic, and clinical characteristics, providing a potential nosology for precision-medicine strategies in DLBCL. (Funded by the Intramural Research Program of the National Institutes of Health and others.).


Assuntos
Perfilação da Expressão Gênica , Heterogeneidade Genética , Linfoma Difuso de Grandes Células B/genética , Mutação , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biópsia , Epigênese Genética , Exoma , Genótipo , Humanos , Estimativa de Kaplan-Meier , Linfoma Difuso de Grandes Células B/classificação , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/mortalidade , Prognóstico , Análise de Sequência de DNA , Transcriptoma
18.
Clin Cancer Res ; 23(15): 4127-4137, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28381416

RESUMO

Purpose: Randomized, multicenter, open-label, phase 2/3 trial investigating lenalidomide versus investigator's choice (IC) in relapsed/refractory diffuse large B-cell lymphoma (DLBCL).Experimental Design: Patients with DLBCL who received ≥2 prior therapies were stratified by DLBCL subtype [germinal center B-cell (GCB) vs. non-GCB; determined by immunohistochemistry (IHC)] and then randomized 1:1 to lenalidomide (25 mg/day, 21 days of 28-day cycle) or IC (gemcitabine, rituximab, etoposide, or oxaliplatin). Crossover to lenalidomide was permitted for IC-treated patients with radiologically confirmed progressive disease. The primary endpoint was overall response rate (ORR). Progression-free survival (PFS), overall survival, and subtype analysis [GCB vs. activated B-cell (ABC)] using gene expression profiling (GEP) were exploratory endpoints.Results: Stage 1: 102 DLBCL patients (by IHC: non-GCB, n = 54; GCB, n = 48) received ≥1 dose of lenalidomide or IC. Hematologic treatment-emergent adverse events with lenalidomide versus IC included neutropenia (42.6%; 36.4%), anemia (33.3%; 47.3%), thrombocytopenia (24.1%; 43.6%), and leukopenia (5.6%; 12.7%), respectively. Overall, lenalidomide-treated patients had an ORR of 27.5% versus 11.8% in IC (ORRs were similar regardless of IHC-defined DLBCL subtype). Median PFS was increased in patients receiving lenalidomide (13.6 weeks) versus IC (7.9 weeks; P = 0.041), with greater improvements in non-GCB patients (15.1 vs. 7.1 weeks, respectively; P = 0.021) compared with GCB (10.1 vs. 9.0 weeks, respectively; P = 0.550).Conclusions: The clinical benefit of lenalidomide monotherapy in DLBCL patients was more evident in the non-GCB subtype. Exploratory analyses suggest that this preferential benefit was more pronounced in the GEP-defined ABC population, demonstrating a need for additional studies of lenalidomide in DLBCL using GEP subtyping. Clin Cancer Res; 23(15); 4127-37. ©2017 AACR.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Prognóstico , Talidomida/análogos & derivados , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Intervalo Livre de Doença , Etoposídeo/administração & dosagem , Feminino , Humanos , Estimativa de Kaplan-Meier , Lenalidomida , Linfoma Difuso de Grandes Células B/patologia , Masculino , Pessoa de Meia-Idade , Compostos Organoplatínicos/administração & dosagem , Oxaliplatina , Modelos de Riscos Proporcionais , Rituximab/administração & dosagem , Talidomida/administração & dosagem , Talidomida/efeitos adversos , Resultado do Tratamento
19.
J Clin Oncol ; 35(15): 1668-1677, 2017 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-28291392

RESUMO

Purpose Mantle cell lymphoma is an aggressive B-cell neoplasm that displays heterogeneous outcomes after treatment. In 2003, the Lymphoma/Leukemia Molecular Profiling Project described a powerful biomarker-the proliferation signature-using gene expression in fresh frozen material. Herein, we describe the training and validation of a new assay that measures the proliferation signature in RNA derived from routinely available formalin-fixed paraffin-embedded (FFPE) biopsies. Methods Forty-seven FFPE biopsies were used to train an assay on the NanoString platform, using microarray gene expression data of matched fresh frozen biopsies as a gold standard. The locked assay was applied to pretreatment FFPE lymph node biopsies from an independent cohort of 110 patients uniformly treated with rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone. Seventeen biopsies were tested across three laboratories to assess assay reproducibility. Results The MCL35 assay, which contained a 17-gene proliferation signature, yielded gene expression of sufficient quality to assign an assay score and risk group in 108 (98%) of 110 archival FFPE biopsies. The MCL35 assay assigned patients to high-risk (26%), standard-risk (29%), and low-risk (45%) groups, with different lengths of overall survival (OS): a median of 1.1, 2.6, and 8.6 years, respectively (log-rank for trend, P < .001). In multivariable analysis, these risk groups and the Mantle Cell Lymphoma International Prognostic Index were independently associated with OS ( P < .001 for both variables). Concordance of risk assignment across the three independent laboratories was 100%. Conclusion The newly developed and validated MCL35 assay for FFPE biopsies uses the proliferation signature to define groups of patients with significantly different OS independent of the Mantle Cell Lymphoma International Prognostic Index. Importantly, the analytic and clinical validity of this assay defines it as a reliable biomarker to support risk-adapted clinical trials.


Assuntos
Biópsia/métodos , Linfoma de Célula do Manto/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Proliferação de Células/fisiologia , Feminino , Formaldeído , Perfilação da Expressão Gênica , Humanos , Linfoma de Célula do Manto/genética , Masculino , Pessoa de Meia-Idade , Inclusão em Parafina , Reprodutibilidade dos Testes , Fixação de Tecidos
20.
Am J Case Rep ; 18: 186-189, 2017 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-28220035

RESUMO

BACKGROUND Laparoscopic cholecystectomy is a commonly performed surgical procedure. In certain situations visualization of the Callot triangle can become difficult due to inflammation, adhesions, and sclerosing of the anatomy. Without being able to obtain the "critical view of safety" (CVS), there is increased risk of damage to vital structures. An alternative approach to the conventional conversion to an open cholecystectomy (OC) would be a laparoscopic subtotal cholecystectomy (LSC). CASE REPORT We present a case of a 56-year-old male patient with acute cholecystitis with a "difficult gallbladder" managed with LSC. Due to poor visualization of the Callot triangle due to adhesions, safe dissection was not feasible. In an effort to avoid injury to the common bile duct (CBD), dissection began at the dome of the gallbladder allowing an alternative view while ensuring safety of critical structures. CONCLUSIONS We discuss the potential benefits and risks of LSC versus conversion to OC. Our discussion incorporates the pathophysiology that allows LSC in this particular circumstance to be successful, and the considerations a surgeon faces in making a decision in management.


Assuntos
Colecistectomia Laparoscópica/métodos , Colecistite/cirurgia , Vesícula Biliar/patologia , Colecistectomia/métodos , Colecistite/diagnóstico , Doença Crônica , Dissecação/métodos , Fibrose , Humanos , Masculino , Pessoa de Meia-Idade , Aderências Teciduais/cirurgia , Resultado do Tratamento
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