Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 52
Filtrar
Mais filtros

País/Região como assunto
Intervalo de ano de publicação
1.
Cell ; 144(1): 27-40, 2011 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-21215367

RESUMO

Cancer is driven by somatically acquired point mutations and chromosomal rearrangements, conventionally thought to accumulate gradually over time. Using next-generation sequencing, we characterize a phenomenon, which we term chromothripsis, whereby tens to hundreds of genomic rearrangements occur in a one-off cellular crisis. Rearrangements involving one or a few chromosomes crisscross back and forth across involved regions, generating frequent oscillations between two copy number states. These genomic hallmarks are highly improbable if rearrangements accumulate over time and instead imply that nearly all occur during a single cellular catastrophe. The stamp of chromothripsis can be seen in at least 2%-3% of all cancers, across many subtypes, and is present in ∼25% of bone cancers. We find that one, or indeed more than one, cancer-causing lesion can emerge out of the genomic crisis. This phenomenon has important implications for the origins of genomic remodeling and temporal emergence of cancer.


Assuntos
Aberrações Cromossômicas , Neoplasias/genética , Neoplasias/patologia , Neoplasias Ósseas/genética , Linhagem Celular Tumoral , Coloração Cromossômica , Feminino , Rearranjo Gênico , Humanos , Leucemia Linfocítica Crônica de Células B/genética , Pessoa de Meia-Idade
2.
Lancet Oncol ; 24(12): 1423-1433, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37944541

RESUMO

BACKGROUND: In the GLOW study, fixed-duration ibrutinib-venetoclax showed superior progression-free survival versus chlorambucil-obinutuzumab in patients with previously untreated chronic lymphocytic leukaemia who were older or had comorbidities, or both, at a median follow up of 27·7 months. In this Article, we report updated outcomes from GLOW after a 46-month median follow-up. METHODS: GLOW was a randomised, multicentre, phase 3 study done at 67 hospital centres across 14 countries. Patients aged 65 years and older or 18-64 years with previously untreated chronic lymphocytic leukaemia and a cumulative illness rating scale score of more than 6 or creatinine clearance less than 70 mL/min, or both, and an Eastern Cooperative Oncology Group performance status of 2 or less were randomly assigned (1:1) via an interactive web system with permuted blocks (block size of four) and stratified by IGHV mutational status and the presence of del11q aberration to the ibrutinib-venetoclax group (three cycles of ibrutinib lead-in [420 mg/day, orally], followed by 12 cycles of ibrutinib plus venetoclax [400 mg/day, orally, including a 5-week dose ramp-up]) or the chlorambucil-obinutuzumab group (six cycles of chlorambucil [0·5 mg/kg, orally, on days 1 and 15 of each cycle], and obinutuzumab [1000 mg, intravenously, on days 1 (or 100 mg on day 1 and 900 mg on day 2), 8, and 15 of cycle 1 and day 1 of cycles 2-6]). The primary endpoint was progression-free survival in the intention-to-treat population, assessed by an independent review committee. The safety population included all randomised patients who received at least one dose of the study treatment. This study is registered with ClinicalTrials.gov (NCT03462719) and the EU Clinical Trials Register (EudraCT 2017-004699-77). FINDINGS: Between May 4, 2018, and April 5, 2019, 211 patients (122 [58%] were male and 89 [42%] were female) were randomly assigned to receive ibrutinib-venetoclax (n=106) or chlorambucil-obinutuzumab (n=105). At a median of 46 months (IQR 43-47) of follow-up, progression-free survival remained superior for the ibrutinib-venetoclax group (hazard ratio 0·214 [95% CI 0·138-0·334]; p<0·0001); 42-month progression-free survival rates were 74·6% (95% CI 65·0-82·0) for ibrutinib-venetoclax and 24·8% (16·5-34·1) for chlorambucil-obinutuzumab. Following the primary analysis, one patient in the chlorambucil-obinutuzumab group had a serious adverse event of myelodysplastic syndrome. Treatment-related deaths were reported in one patient receiving ibrutinib-venetoclax (cardiac failure, pneumonia, and sinus node dysfunction) and in one patient receiving chlorambucil-obinutuzumab (pneumonia). There were 15 deaths in the ibrutinib-venetoclax group (of which three were due to post-treatment infections) and 30 deaths in the chlorambucil-obinutuzumab group (of which 10 were due to post-treatment infections). INTERPRETATION: After 4 years of follow-up, ibrutinib-venetoclax continues to significantly prolong progression-free survival (vs chemoimmunotherapy) in patients with previously untreated chronic lymphocytic leukaemia, supporting its use as a first-line option. FUNDING: Janssen Research & Development and Pharmacyclics.


Assuntos
Leucemia Linfocítica Crônica de Células B , Pneumonia , Feminino , Humanos , Masculino , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Clorambucila/efeitos adversos , Clorambucila/uso terapêutico , Seguimentos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Pneumonia/induzido quimicamente
3.
Br J Haematol ; 197(3): 310-319, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35235680

RESUMO

Post-transplant lymphoproliferative disease (PTLD) is a life-threatening complication of solid-organ transplantation (SOT). We present the incidence and outcomes of PTLD in a cohort of 5365 SOT recipients over a 20-year period at two UK transplant centres. With a median follow-up of 7.7 years, 142 of 5365 patients have developed PTLD. Cumulative incidence was 18% at five years after multivisceral transplant and 1%-3% at five years following the other SOT types. Twenty-year cumulative incidence was 2%-3% following liver and heart transplantation and 10% following kidney transplantation. Median overall survival (OS) following SOT was 16 years, which is significantly reduced compared with the age-adjusted UK population. There is relatively high early mortality following diagnosis of PTLD and only patients surviving two years regained a longer-term survival approaching the non-PTLD SOT cohort. Of 90 patients with monomorphic PTLD, diffuse large B-cell lymphoma, 66 were treated with first-line rituximab monotherapy and 24 received first-line rituximab plus chemotherapy. Up-front rituximab monotherapy does not appear to compromise OS, but the number of patients dying from non-lymphoma causes before and after treatment remains high with both treatment approaches. Multivariate analysis of all 90 monomorphic PTLD patients identified an International Prognostic Index (IPI) of 3+ as the strongest pretreatment variable associating with inferior one-year OS.


Assuntos
Infecções por Vírus Epstein-Barr , Transtornos Linfoproliferativos , Transplante de Órgãos , Infecções por Vírus Epstein-Barr/complicações , Humanos , Incidência , Transtornos Linfoproliferativos/tratamento farmacológico , Transtornos Linfoproliferativos/epidemiologia , Transtornos Linfoproliferativos/etiologia , Transplante de Órgãos/efeitos adversos , Estudos Retrospectivos , Rituximab/uso terapêutico , Reino Unido/epidemiologia
4.
Br J Haematol ; 197(5): 558-572, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35191541

RESUMO

This guideline was compiled according to the British Society for Haematology (BSH) process at BSH Guidelines Process 2016 (b-s-h.org.uk). The Grading of Recommendations Assessment, Development and Evaluation (GRADE) nomenclature was used to evaluate levels of evidence and to assess the strength of recommendations. The GRADE criteria can be found at http://www.gradeworkinggroup.org. Recommendations are based on a review of the literature using Medline, PubMed/Medline and Cochrane searches beginning from 2013 up to January 2021. The following search terms were used: [Hodgkin lymphoma OR Hodgkin disease] NOT non-Hodgkin; AND [chemotherapy OR radiotherapy]; AND [elderly]; AND [teenage OR adolescent OR young adult]; AND [pregnancy]. Filters were applied to include only publications written in English, studies carried out in humans, clinical conferences, congresses, clinical trials, clinical studies, meta-analyses, multicentre studies and randomised controlled trials. References pre-2013 were taken from the previous version of this guideline.1 Review of the manuscript was performed by the British Society for Haematology (BSH) Guidelines Committee Haematology Oncology Taskforce, the BSH Guidelines Committee and the Haematology Oncology sounding board of BSH.


Assuntos
Hematologia , Doença de Hodgkin , Linfoma não Hodgkin , Adolescente , Idoso , Doença de Hodgkin/terapia , Humanos
5.
Haematologica ; 107(2): 489-499, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33567811

RESUMO

Angioimmunoblastic T-cell lymphoma (AITL) and peripheral T-cell lymphoma with T follicular helper phenotype (PTCL-TFH) are a group of complex clinicopathological entities that originate from T follicular helper cells and share a similar mutation profile. Their diagnosis is often a challenge, particularly at an early stage, because of a lack of specific histological and immunophenotypic features, paucity of neoplastic T cells and prominent polymorphous infiltrate. We investigated whether the lymphoma-associated RHOA Gly17Val (c.50G>T) mutation, occurring in 60% of cases, is present in the early "reactive" lesions, and whether mutation analysis could help to advance the early diagnosis of lymphoma. The RHOA mutation was detected by quantitative polymerase chain reaction with a locked nucleic acid probe specific to the mutation, and a further peptide nucleic acid clamp oligonucleotide to suppress the amplification of the wild-type allele. The quantitative polymerase chain reaction assay was highly sensitive and specific, detecting RHOA Gly17Val at an allele frequency of 0.03%, but not other changes in Gly17, nor in 61 controls. Among the 37 cases of AITL and PTCL-TFH investigated, RHOA Gly17Val was detected in 62.2% (23/37) of which 19 had multiple biopsies including preceding biopsies in ten and follow-up biopsies in 11 cases. RHOA Gly17Val was present in each of these preceding or follow-up biopsies including 18 specimens that showed no evidence of lymphoma by combined histological, immunophenotypic and clonality analyses. The mutation was seen in biopsies 0-26.5 months (mean 7.87 months) prior to the lymphoma diagnosis. Our results show that RHOA Gly17Val mutation analysis is valuable in the early detection of AITL and PTCL-TFH.


Assuntos
Linfadenopatia Imunoblástica , Linfoma de Células T Periférico , Linfoma de Células T , Diagnóstico Precoce , Humanos , Linfadenopatia Imunoblástica/diagnóstico , Linfoma de Células T/diagnóstico , Linfoma de Células T/genética , Linfoma de Células T/patologia , Linfoma de Células T Periférico/diagnóstico , Linfoma de Células T Periférico/genética , Linfoma de Células T Periférico/patologia , Mutação , Fenótipo , Linfócitos T Auxiliares-Indutores/patologia , Proteína rhoA de Ligação ao GTP/genética
7.
Ann Hematol ; 100(4): 1049-1058, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33641019

RESUMO

Treatment with ABVD (doxorubicin, bleomycin, vinblastine, and dacarbazine) or escalated(e)-BEACOPP (bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisolone) remains the international standard of care for advanced-stage classical Hodgkin lymphoma (HL). We performed a retrospective, multicentre analysis of 221 non-trial ("real-world") patients, aged 16-59 years, diagnosed with advanced-stage HL in the Anglia Cancer Network between 2004 and 2014, treated with ABVD or eBEACOPP, and compared outcomes with 1088 patients in the Response-Adjusted Therapy for Advanced Hodgkin Lymphoma (RATHL) trial, aged 18-59 years, with median follow-up of 87.0 and 69.5 months, respectively. Real-world ABVD patients (n=177) had highly similar 5-year progression-free survival (PFS) and overall survival (OS) compared with RATHL (PFS 79.2% vs 81.4%; OS 92.9% vs 95.2%), despite interim positron-emission tomography-computed tomography (PET/CT)-guided dose-escalation being predominantly restricted to trial patients. Real-world eBEACOPP patients (n=44) had superior PFS (95.5%) compared with real-world ABVD (HR 0.20, p=0.027) and RATHL (HR 0.21, p=0.015), and superior OS for higher-risk (international prognostic score ≥3 [IPS 3+]) patients compared with real-world IPS 3+ ABVD (100% vs 84.5%, p=0.045), but not IPS 3+ RATHL patients. Our data support a PFS, but not OS, advantage for patients with advanced-stage HL treated with eBEACOPP compared with ABVD and suggest higher-risk patients may benefit disproportionately from more intensive therapy. However, increased access to effective salvage therapies might minimise any OS benefit from reduced relapse rates after frontline therapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Doença de Hodgkin/tratamento farmacológico , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Bleomicina/administração & dosagem , Ensaios Clínicos como Assunto/estatística & dados numéricos , Terapia Combinada , Ciclofosfamida/administração & dosagem , Dacarbazina/administração & dosagem , Doxorrubicina/administração & dosagem , Inglaterra/epidemiologia , Etoposídeo/administração & dosagem , Feminino , Seguimentos , Transplante de Células-Tronco Hematopoéticas , Doença de Hodgkin/mortalidade , Doença de Hodgkin/terapia , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estudos Multicêntricos como Assunto/estatística & dados numéricos , Prednisona/administração & dosagem , Gravidez , Complicações Neoplásicas na Gravidez/tratamento farmacológico , Complicações Neoplásicas na Gravidez/epidemiologia , Procarbazina/administração & dosagem , Intervalo Livre de Progressão , Estudos Retrospectivos , Resultado do Tratamento , Vimblastina/administração & dosagem , Vincristina/administração & dosagem , Adulto Jovem
8.
J Pathol ; 250(3): 346-357, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31859368

RESUMO

Angioimmunoblastic T-cell lymphoma (AITL) is a neoplastic proliferation of T follicular helper cells with clinical and histological presentations suggesting a role of antigenic drive in its development. Genetically, it is characterized by a stepwise acquisition of somatic mutations, with early mutations involving epigenetic regulators (TET2, DNMT3A) and occurring in haematopoietic stem cells, with subsequent changes involving signaling molecules (RHOA, VAV1, PLCG1, CD28) critical for T-cell biology. To search for evidence of potential oncogenic cooperation between genetic changes and intrinsic T cell receptor (TCR) signaling, we investigated somatic mutations and T-cell receptor ß (TRB) rearrangement in 119 AITL, 11 peripheral T-cell lymphomas with T follicular helper phenotype (PTCL-TFH), and 25 PTCL-NOS using Fluidigm polymerase chain reaction (PCR) and Illumina MiSeq sequencing. We confirmed frequent TET2, DNMT3A, and RHOA mutations in AITL (72%, 34%, 61%) and PTCL-TFH (73%, 36%, 45%) and showed multiple TET2 mutations (2 or 3) in 57% of the involved AITL and PTCL-TFH. Clonal TRB rearrangement was seen in 76 cases with multiple functional rearrangements (2-4) in 18 cases (24%). In selected cases, we confirmed bi-clonal T-cell populations and further demonstrated that these independent T-cell populations harboured identical TET2 mutations by using BaseScope in situ hybridization, suggesting their derivation from a common TET2 mutant progenitor cell population. Furthermore, both T-cell populations expressed CD4. Finally, in comparison with tonsillar TFH cells, both AITL and PTCL-TFH showed a significant overrepresentation of several TRB variable family members, particularly TRBV19*01. Our findings suggest the presence of parallel neoplastic evolutions from a common TET2 mutant haematopoietic progenitor pool in AITL and PTCL-TFH, albeit to be confirmed in a large series of cases. The biased TRBV usage in these lymphomas suggests that antigenic stimulation may play an important role in predilection of T cells to clonal expansion and malignant transformation. © 2019 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.


Assuntos
Proteínas de Ligação a DNA/genética , Linfadenopatia Imunoblástica/imunologia , Linfoma de Células T/imunologia , Proteínas Proto-Oncogênicas/genética , Idoso , Alelos , Dioxigenases , Frequência do Gene , Humanos , Linfadenopatia Imunoblástica/genética , Linfadenopatia Imunoblástica/patologia , Linfoma de Células T/genética , Linfoma de Células T/patologia , Pessoa de Meia-Idade , Mutação , Receptores de Antígenos de Linfócitos T/genética , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Auxiliares-Indutores/patologia
9.
Blood ; 127(4): 436-48, 2016 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-26508782

RESUMO

The crucial dependence of chronic lymphocytic leukemia (CLL) cells on signals derived from the B cell receptor (BCR) has encouraged the development of new inhibitors, which interfere with BCR signaling and demonstrate clinical benefits in nearly all patients. In addition, signaling through Toll-like receptor (TLR) 9 of the innate immune system has been shown to further contribute to the activation of CLL cells. However, responses to TLR9 engagement are not uniform, but diametrically opposed with cell death in some patients and cell proliferation in others. We now provide evidence that heterogeneous responses to TLR agonists are related to differences in the ability of CLL cells to activate the BCR-associated kinase Syk. Notably, expression of ZAP-70 appears to be of crucial importance for TLR9-mediated activation of Syk. We show that the activation of Syk provides an antiapoptotic signal, which is independent of Mcl-1, Bcl-2, and Bcl-XL, but related to the degradation of the proapoptotic Bim. Mechanistically, TLR9-mediated antiapoptotic signals in ZAP-70-positive CLL trigger secretion of immunoglobulin M, which then serves as (auto-) antigen for a prosurvival BCR signal. Thus, our data show that single activation of the innate immune receptor TLR9 is sufficient to fully engage BCR signaling in ZAP-70-positive CLL, protecting malignant cells from apoptosis. We conclude that the integration of TLR signaling into an adaptive immune response can further promote survival of CLL cells and may contribute to the unfavorable prognosis of ZAP-70-positive CLL.


Assuntos
Imunidade Adaptativa , Imunidade Inata , Leucemia Linfocítica Crônica de Células B/imunologia , Proteína-Tirosina Quinase ZAP-70/imunologia , Linfócitos B/imunologia , Linfócitos B/patologia , Linhagem Celular , Sobrevivência Celular , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/imunologia , Leucemia Linfocítica Crônica de Células B/patologia , Proteínas Tirosina Quinases/imunologia , Receptores de Antígenos de Linfócitos B/imunologia , Transdução de Sinais , Quinase Syk , Receptor Toll-Like 9/imunologia
10.
Blood ; 128(19): 2319-2326, 2016 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-27528712

RESUMO

Chronic lymphocytic leukemia (CLL) can be familial; however, thus far no rare germ line disruptive alleles for CLL have been identified. We performed whole-exome sequencing of 66 CLL families, identifying 4 families where loss-of-function mutations in protection of telomeres 1 (POT1) co-segregated with CLL. The p.Tyr36Cys mutation is predicted to disrupt the interaction between POT1 and the telomeric overhang. The c.1164-1G>A splice-site, p.Gln358SerfsTer13 frameshift, and p.Gln376Arg missense mutations are likely to impact the interaction between POT1 and adrenocortical dysplasia homolog (ACD), which is a part of the telomere-capping shelterin complex. We also identified mutations in ACD (c.752-2A>C) and another shelterin component, telomeric repeat binding factor 2, interacting protein (p.Ala104Pro and p.Arg133Gln), in 3 CLL families. In a complementary analysis of 1083 cases and 5854 controls, the POT1 p.Gln376Arg variant, which has a global minor allele frequency of 0.0005, conferred a 3.61-fold increased risk of CLL (P = .009). This study further highlights telomere dysregulation as a key process in CLL development.


Assuntos
Mutação em Linhagem Germinativa/genética , Leucemia Linfocítica Crônica de Células B/genética , Proteínas de Ligação a Telômeros/genética , Sequência de Aminoácidos , Feminino , Humanos , Masculino , Linhagem , Sítios de Splice de RNA/genética , Complexo Shelterina , Homeostase do Telômero , Proteínas de Ligação a Telômeros/química
11.
Blood ; 127(23): 2847-55, 2016 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-26941398

RESUMO

The activating mutation of the BRAF serine/threonine protein kinase (BRAF V600E) is the key driver mutation in hairy cell leukemia (HCL), suggesting opportunities for therapeutic targeting. We analyzed the course of 21 HCL patients treated with vemurafenib outside of trials with individual dosing regimens (240-1920 mg/d; median treatment duration, 90 days). Vemurafenib treatment improved blood counts in all patients, with platelets, neutrophils, and hemoglobin recovering within 28, 43, and 55 days (median), respectively. Complete remission was achieved in 40% (6/15 of evaluable patients) and median event-free survival was 17 months. Response rate and kinetics of response were independent of vemurafenib dosing. Retreatment with vemurafenib led to similar response patterns (n = 6). Pharmacodynamic analysis of BRAF V600E downstream targets showed that vemurafenib (480 mg/d) completely abrogated extracellular signal-regulated kinase phosphorylation of hairy cells in vivo. Typical side effects also occurred at low dosing regimens. We observed the development of acute myeloid lymphoma (AML) subtype M6 in 1 patient, and the course suggested disease acceleration triggered by vemurafenib. The phosphatidylinositol 3-kinase hotspot mutation (E545K) was identified in the AML clone, providing a potential novel mechanism for paradoxical BRAF activation. These data provide proof of dependence of HCL on active BRAF signaling. We provide evidence that antitumor and side effects are observed with 480 mg vemurafenib, suggesting that dosing regimens in BRAF-driven cancers could warrant reassessment in trials with implications for cost of cancer care.


Assuntos
Antineoplásicos/administração & dosagem , Indóis/administração & dosagem , Leucemia de Células Pilosas/tratamento farmacológico , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Sulfonamidas/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/efeitos adversos , Relação Dose-Resposta a Droga , Humanos , Indóis/efeitos adversos , Leucemia de Células Pilosas/mortalidade , Pessoa de Meia-Idade , Recidiva , Retratamento , Estudos Retrospectivos , Rituximab/uso terapêutico , Sulfonamidas/efeitos adversos , Análise de Sobrevida , Resultado do Tratamento , Vemurafenib
12.
Genome Res ; 23(11): 1874-84, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23742949

RESUMO

The adaptive immune response selectively expands B- and T-cell clones following antigen recognition by B- and T-cell receptors (BCR and TCR), respectively. Next-generation sequencing is a powerful tool for dissecting the BCR and TCR populations at high resolution, but robust computational analyses are required to interpret such sequencing. Here, we develop a novel computational approach for BCR repertoire analysis using established next-generation sequencing methods coupled with network construction and population analysis. BCR sequences organize into networks based on sequence diversity, with differences in network connectivity clearly distinguishing between diverse repertoires of healthy individuals and clonally expanded repertoires from individuals with chronic lymphocytic leukemia (CLL) and other clonal blood disorders. Network population measures defined by the Gini Index and cluster sizes quantify the BCR clonality status and are robust to sampling and sequencing depths. BCR network analysis therefore allows the direct and quantifiable comparison of BCR repertoires between samples and intra-individual population changes between temporal or spatially separated samples and over the course of therapy.


Assuntos
Linfócitos B/imunologia , Genes de Cadeia Pesada de Imunoglobulina , Sequenciamento de Nucleotídeos em Larga Escala , Leucemia Linfocítica Crônica de Células B/imunologia , Receptores de Antígenos de Linfócitos B/genética , Imunidade Adaptativa , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Linhagem Celular Tumoral , Células Clonais , Biologia Computacional , Feminino , Humanos , Leucemia Linfocítica Crônica de Células B/patologia , Masculino , Pessoa de Meia-Idade , Receptores de Antígenos de Linfócitos B/imunologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Adulto Jovem
13.
BMC Immunol ; 15: 29, 2014 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-25189176

RESUMO

BACKGROUND: Deep-sequencing methods are rapidly developing in the field of B-cell receptor (BCR) and T-cell receptor (TCR) diversity. These promise to revolutionise our understanding of adaptive immune dynamics, identify novel antibodies, and allow monitoring of minimal residual disease. However, different methods for BCR and TCR enrichment and amplification have been proposed. Here we perform the first systematic comparison between different methods of enrichment, amplification and sequencing for generating BCR and TCR repertoires using large sample numbers. RESULTS: Resampling from the same RNA or cDNA pool results in highly correlated and reproducible repertoires, but resampling low frequency clones leads to stochastic variance. Repertoires generated by different sequencing methods (454 Roche and Illumina MiSeq) and amplification methods (multiplex PCR, 5' Rapid amplification of cDNA ends (5'RACE), and RNA-capture) are highly correlated, and resulting IgHV gene frequencies between the different methods were not significantly different. Read length has an impact on captured repertoire structure, and ultimately full-length BCR sequences are most informative for repertoire analysis as diversity outside of the CDR is very useful for phylogenetic analysis. Additionally, we show RNA-based BCR repertoires are more informative than using DNA. CONCLUSIONS: Repertoires generated by different sequencing and amplification methods are consistent, but we show that read lengths, depths and error profiles should be considered in experimental design, and multiple sampling approaches could be employed to minimise stochastic sampling variation. This detailed investigation of immune repertoire sequencing methods is essential for informing basic and clinical research.


Assuntos
Receptores de Antígenos de Linfócitos B/genética , Análise de Sequência de DNA/métodos , DNA/genética , Variação Genética , Humanos , RNA/genética , Processos Estocásticos
14.
Clin Case Rep ; 11(1): e6838, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36644610

RESUMO

Lactic acidosis and hypoglycemia are rare presentations of malignancy with a poor prognosis. We present the case of a mantle cell lymphoma patient who relapsed with lactic acidosis and hypoglycemia. Although blood glucose, pH, and lactate normalized following chemotherapy and intensive care support, the patient died from ventilator-associated pneumonia.

15.
EJHaem ; 3(4): 1316-1320, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36467809

RESUMO

PEP-C (prednisolone, etoposide, procarbazine and cyclophosphamide) is an orally administered daily chemotherapy regimen used with palliative intent in relapsed refractory lymphoma. To our knowledge, no data on PEP-C have been reported since the original group described the regimen. Here we present a multicentre retrospective cohort reporting our use of PEP-C in 92 patients over an 8-year period. We find that even heavily pretreated lymphoma can respond to PEP-C, particularly low-grade lymphoma (including mantle cell) and lymphoma that was sensitive to the previous line of systemic therapy (chemosensitive). These characteristics may help in the selection of patients likely to derive benefit. The median overall survival of patients with chemosensitive lymphoma treated with PEP-C is 217 days. Within the limitations of a retrospective cohort, we find that PEP-C is well tolerated: the most common toxicity leading to discontinuation is marrow suppression. We suggest that PEP-C should be considered for patients with relapsed refractory lymphoma in two settings: first, where there is no licensed alternative; and second, where the licensed alternative is an intravenous drug and the patient would prefer to choose an oral chemotherapy option.

16.
Br J Haematol ; 155(5): 609-12, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21910720

RESUMO

The BRAF V600E mutation has recently been described in all cases of hairy cell leukaemia (HCL). We have developed and validated a rapid and sensitive high-resolution melting analysis (HRMA) assay that detects BRAF exon 15 mutations when hairy cells are as low as 5-10% in a sample. All 48 HCL patients were positive for the BRAF V600E mutation, while 114 non-HCL cases were all V600E negative. Interestingly, we detected a novel BRAF D594N mutation in one patient with multiple myeloma. The HRMA assay offers a useful tool to aid the laboratory diagnosis of HCL.


Assuntos
Éxons , Leucemia de Células Pilosas/genética , Leucemia de Células Pilosas/patologia , Transtornos Linfoproliferativos/genética , Mutação , Proteínas Proto-Oncogênicas B-raf/genética , Análise de Sequência de DNA/métodos , Técnicas Genéticas , Células HT29 , Humanos
17.
N Engl J Med ; 359(26): 2778-89, 2008 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-19109573

RESUMO

BACKGROUND: The myeloproliferative disorders are clonal disorders with frequent somatic gain-of-function alterations affecting tyrosine kinases. In these diseases, there is an increase in DNA damage and a risk of progression to acute leukemia. The molecular mechanisms in myeloproliferative disorders that prevent apoptosis induced by damaged DNA are obscure. METHODS: We searched for abnormalities of the proapoptotic Bcl-x(L) deamidation pathway in primary cells from patients with chronic myeloid leukemia (CML) or polycythemia vera, myeloproliferative disorders associated with the BCR-ABL fusion kinase and the Janus tyrosine kinase 2 (JAK2) V617F mutation, respectively. RESULTS: The Bcl-x(L) deamidation pathway was inhibited in myeloid cells, but not T cells, in patients with CML or polycythemia vera. DNA damage did not increase levels of the amiloride-sensitive sodium-hydrogen exchanger isoform 1 (NHE-1), intracellular pH, Bcl-x(L) deamidation, and apoptosis. Inhibition of the pathway was reversed by enforced alkalinization or overexpression of NHE-1, leading to a restoration of apoptosis. In patients with CML, the pathway was blocked in CD34+ progenitor cells and mature myeloid cells. Imatinib or JAK2 inhibitors reversed inhibition of the pathway in cells from patients with CML and polycythemia vera, respectively, but not in cells from a patient with resistance to imatinib because of a mutation in the BCR-ABL kinase domain. CONCLUSIONS: BCR-ABL and mutant JAK2 inhibit the Bcl-x(L) deamidation pathway and the apoptotic response to DNA damage in primary cells from patients with CML or polycythemia vera.


Assuntos
Dano ao DNA , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Policitemia Vera/genética , Proteína bcl-X/fisiologia , Apoptose , Proteínas de Transporte de Cátions/genética , Linhagem Celular Tumoral , Dano ao DNA/genética , Desaminação , Proteínas de Fusão bcr-abl/genética , Proteínas de Fusão bcr-abl/fisiologia , Técnicas de Transferência de Genes , Genes abl/genética , Humanos , Janus Quinase 2/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/sangue , Leucócitos Mononucleares , Transtornos Mieloproliferativos/sangue , Transtornos Mieloproliferativos/genética , Policitemia Vera/sangue , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/fisiologia , Transdução de Sinais/genética , Trocador 1 de Sódio-Hidrogênio , Trocadores de Sódio-Hidrogênio/genética , Proteína bcl-X/genética
18.
Proc Natl Acad Sci U S A ; 105(35): 13081-6, 2008 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-18723673

RESUMO

During the clonal expansion of cancer from an ancestral cell with an initiating oncogenic mutation to symptomatic neoplasm, the occurrence of somatic mutations (both driver and passenger) can be used to track the on-going evolution of the neoplasm. All subclones within a cancer are phylogenetically related, with the prevalence of each subclone determined by its evolutionary fitness and the timing of its origin relative to other subclones. Recently developed massively parallel sequencing platforms promise the ability to detect rare subclones of genetic variants without a priori knowledge of the mutations involved. We used ultra-deep pyrosequencing to investigate intraclonal diversification at the Ig heavy chain locus in 22 patients with B-cell chronic lymphocytic leukemia. Analysis of a non-polymorphic control locus revealed artifactual insertions and deletions resulting from sequencing errors and base substitutions caused by polymerase misincorporation during PCR amplification. We developed an algorithm to differentiate genuine haplotypes of somatic hypermutations from such artifacts. This proved capable of detecting multiple rare subclones with frequencies as low as 1 in 5000 copies and allowed the characterization of phylogenetic interrelationships among subclones within each patient. This study demonstrates the potential for ultra-deep resequencing to recapitulate the dynamics of clonal evolution in cancer cell populations.


Assuntos
Linhagem da Célula , Leucemia Linfocítica Crônica de Células B/patologia , Análise de Sequência de DNA/métodos , Algoritmos , Sequência de Bases , Células Clonais , Rearranjo Gênico de Cadeia Pesada de Linfócito B/genética , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Leucemia Linfocítica Crônica de Células B/genética , Dados de Sequência Molecular , Nucleotídeos
19.
Target Oncol ; 16(3): 295-308, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33687623

RESUMO

Dysregulation of phosphatidylinositol 3-kinase (PI3K)/protein kinase B/mammalian target of rapamycin signaling is common in both indolent and aggressive forms of malignant lymphoma, for which several targeted therapies have been developed. Copanlisib is a highly selective and potent intravenous pan-class I PI3K inhibitor that has demonstrated durable objective responses and a manageable safety profile in heavily pre-treated patients with indolent lymphomas. As a result, copanlisib monotherapy received accelerated approval from the US Food and Drug Administration for the treatment of adults with relapsed follicular lymphoma who have received at least two systemic therapies, and breakthrough designation for patients with pre-treated relapsed or refractory marginal zone lymphoma. Hyperglycemia and hypertension are among the most frequently reported adverse events with copanlisib monotherapy, and are infusion-related, transient, and manageable with standard therapies. Mild diarrhea is also a common adverse event with copanlisib monotherapy; there is no evidence of worsening severity of diarrhea, or serious gastrointestinal toxicities such as colitis or severe liver enzyme elevations, which have been reported with orally administered PI3K inhibitors. The intravenous route of administration and intermittent dosing schedule of copanlisib may support a favorable tolerability profile over continually administered oral alternatives. Ongoing studies of copanlisib in combination with rituximab and standard-of-care chemotherapy in patients with relapsed indolent lymphoma have the potential to support the use of copanlisib in the second-line setting, providing a much-needed additional therapeutic option in this underserved patient population.


Assuntos
Linfoma/tratamento farmacológico , Pirimidinas/uso terapêutico , Quinazolinas/uso terapêutico , Humanos , Linfoma/patologia , Pirimidinas/farmacologia , Quinazolinas/farmacologia
20.
Blood Adv ; 5(3): 823-828, 2021 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-33560394

RESUMO

Marginal zone lymphoma (MZL) is challenging to treat, with many patients relapsing following initial treatment. We report the long-term efficacy and safety of copanlisib, a pan-class I phosphoinositide 3-kinase (PI3K) inhibitor, in the subset of 23 patients with relapsed/refractory MZL treated in the phase 2 CHRONOS-1 study (#NCT01660451, Part B; www.clinicaltrials.gov). Patients had a median of 3 prior lines of therapy, including rituximab and alkylating agents, and received IV copanlisib 60 mg on days 1, 8, and 15 of 28-day cycles for a median of 23 weeks. The objective response rate was 78.3% (18/23; 3 complete responses and 15 partial responses). The median duration of response was 17.4 months (median follow-up, 9.4 months), and median time to response was 2.1 months. Median progression-free survival was 24.1 months (median follow-up, 10.3 months), and median overall survival was not reached (median follow-up, 28.4 months). The most common all-grade treatment-emergent adverse events (TEAEs) included fatigue (52.2%, 12/23), diarrhea, and transient, infusion-related hyperglycemia (each 47.8%, 11/23). Nineteen patients (82.6%) had grade 3/4 TEAEs, most commonly transient, infusion-related hyperglycemia and hypertension (each 39.1%, 9/23). TEAEs led to dose reduction or dose interruptions /delays in 9 patients (39.1%) and 18 patients (78.3%), respectively. Patients with activated PI3K/B-cell antigen receptor signaling had improved response rates. Overall, copanlisib demonstrated strong efficacy, with a short time to objective response, improved objective response rate with longer treatment duration, durable responses, and manageable safety, in line with previous reports. These data provide rationale for long-term treatment with copanlisib in patients with relapsed/refractory MZL.


Assuntos
Linfoma de Zona Marginal Tipo Células B , Humanos , Linfoma de Zona Marginal Tipo Células B/tratamento farmacológico , Recidiva Local de Neoplasia , Fosfatidilinositol 3-Quinases , Pirimidinas , Quinazolinas
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA