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SARS-CoV-2 has caused over 2 million deaths in little over a year. Vaccines are being deployed at scale, aiming to generate responses against the virus spike. The scale of the pandemic and error-prone virus replication is leading to the appearance of mutant viruses and potentially escape from antibody responses. Variant B.1.1.7, now dominant in the UK, with increased transmission, harbors 9 amino acid changes in the spike, including N501Y in the ACE2 interacting surface. We examine the ability of B.1.1.7 to evade antibody responses elicited by natural SARS-CoV-2 infection or vaccination. We map the impact of N501Y by structure/function analysis of a large panel of well-characterized monoclonal antibodies. B.1.1.7 is harder to neutralize than parental virus, compromising neutralization by some members of a major class of public antibodies through light-chain contacts with residue 501. However, widespread escape from monoclonal antibodies or antibody responses generated by natural infection or vaccination was not observed.
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Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/imunologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Células CHO , COVID-19/epidemiologia , Chlorocebus aethiops , Cricetulus , Células HEK293 , Humanos , Pandemias , Ligação Proteica , Relação Estrutura-Atividade , Células VeroRESUMO
Human IGHV1-69-encoded broadly neutralizing antibodies (bnAbs) that target the hepatitis C virus (HCV) envelope glycoprotein (Env) E2 are important for protection against HCV infection. An IGHV1-69 ortholog gene, VH1.36, is preferentially used for bnAbs isolated from HCV Env-immunized rhesus macaques (RMs). Here, we studied the genetic, structural, and functional properties of VH1.36-encoded bnAbs generated by vaccination, in comparison to IGHV1-69-encoded bnAbs from HCV patients. Global B cell repertoire analysis confirmed the expansion of VH1.36-derived B cells in immunized animals. Most E2-specific, VH1.36-encoded antibodies cross-neutralized HCV. Crystal structures of two RM bnAbs with E2 revealed that the RM bnAbs engaged conserved E2 epitopes using similar molecular features as human bnAbs but with a different binding mode. Longitudinal analyses of the RM antibody repertoire responses during immunization indicated rapid lineage development of VH1.36-encoded bnAbs with limited somatic hypermutation. Our findings suggest functional convergence of a germline-encoded bnAb response to HCV Env with implications for vaccination in humans.
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Anticorpos Neutralizantes/imunologia , Células Germinativas/imunologia , Glicoproteínas/imunologia , Hepacivirus/imunologia , Hepatite C/imunologia , Macaca mulatta/imunologia , Proteínas do Envelope Viral/imunologia , Animais , Linfócitos B/imunologia , Células CHO , Linhagem Celular , Cricetulus , Epitopos/imunologia , Células HEK293 , Hepatite C/virologia , Humanos , Estudos Longitudinais , Macaca mulatta/virologia , Receptores de Antígenos de Linfócitos B/imunologia , Vacinação/métodosRESUMO
Respiratory syncytial virus (RSV) is a leading cause of infant mortality, and there are currently no licensed vaccines to protect this vulnerable population. A comprehensive understanding of infant antibody responses to natural RSV infection would facilitate vaccine development. Here, we isolated more than 450 RSV fusion glycoprotein (F)-specific antibodies from 7 RSV-infected infants and found that half of the antibodies recognized only two antigenic sites. Antibodies targeting both sites showed convergent sequence features, and structural studies revealed the molecular basis for their recognition of RSV F. A subset of antibodies targeting one of these sites displayed potent neutralizing activity despite lacking somatic mutations, and similar antibodies were detected in RSV-naive B cell repertoires, suggesting that expansion of these B cells in infants may be possible with suitably designed vaccine antigens. Collectively, our results provide fundamental insights into infant antibody responses and a framework for the rational design of age-specific RSV vaccines.
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Anticorpos Neutralizantes/biossíntese , Anticorpos Antivirais/biossíntese , Infecções por Vírus Respiratório Sincicial/imunologia , Hipermutação Somática de Imunoglobulina , Proteínas Virais de Fusão/imunologia , Animais , Linfócitos B/imunologia , Humanos , Lactente , Camundongos , Vacinas contra Vírus Sincicial Respiratório/imunologiaRESUMO
BACKGROUND: Overall, the prognosis of patients with chronic lymphocytic leukemia (CLL) in the early phase of the disease (Rai 0, Binet A) is favorable; some patients never require therapy. However, some patients require intervention shortly after diagnosis. In the past decade, several risk scores (RS) have been developed to predict disease progression, yet some patients are misclassified. On the other hand, IGHV subset 2 (IGHV2) predicts poor outcomes. METHODS: A retrospective and multicentric study was conducted to compare the accuracy of five different RS (IPS-E, CR0, AIPS-E, CLL-IPI, and Barcelona-Brno) to predict disease progression in 781 stage A previously untreated patients with CLL. As an exploratory analysis, it was further investigated whether the inclusion of the IGHV2 as a poor prognostic parameter improved the accuracy of RS. RESULTS: All the scores identified a similar group of patients with CLL in early stage with low-, intermediate-, and high-risk progression. Discrimination was high and similar in all RS (c-index = 0.74-0.79, area under the curve = 0.7-0.75), as well as calibration (p = .98) and parsimony, although CLL-IPI showed the best results (Akaike information criterion = 441). A total of 34.4% of patients were categorized within the same RS and concordance was at least moderate between RS. CONCLUSION: Moreover, the results suggest that IGHV2 may improve the accuracy of RS.
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The potential prognostic influence of genetic aberrations on chronic lymphocytic leukaemia (CLL) can vary based on various factors, such as the immunoglobulin heavy variable (IGHV) status. We conducted an integrative analysis on genetic abnormalities identified through cytogenetics and targeted next-generation sequencing in 536 CLL patients receiving first-line chemo(immuno)therapies (CIT) as part of two prospective trials. We evaluated the prognostic implications of the main abnormalities, with specific attention to their relative impact according to IGHV status. In the entire cohort, unmutated (UM)-IGHV, complex karyotype, del(11q) and ATM mutations correlated significantly with shorter progression-free survival (PFS). Focusing on the subset of mutated IGHV (M-IGHV) patients, univariate analysis showed that complex karyotype, del(11q), SF3B1 and SAMHD1 mutations were associated with significant lower PFS. The prognostic influence varied based on the patient's IGHV status, as these abnormalities did not affect outcomes in the UM-IGHV subgroup. TP53 mutations had no significant impact on outcomes in the M-IGHV subgroup. Our findings highlight the diverse prognostic influence of genetic aberrations depending on the IGHV status in symptomatic CLL patients receiving first-line CIT. The prognosis of gene mutations and cytogenetic abnormalities needs to be investigated with a compartmentalized methodology, taking into account the IGVH status of patients receiving first-line BTK and/or BCL2 inhibitors.
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Cromossomos Humanos Par 17 , Cadeias Pesadas de Imunoglobulinas , Leucemia Linfocítica Crônica de Células B , Mutação , Humanos , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/mortalidade , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Prognóstico , Cadeias Pesadas de Imunoglobulinas/genética , Estudos Prospectivos , Cromossomos Humanos Par 17/genética , Deleção Cromossômica , Adulto , Idoso de 80 Anos ou mais , Região Variável de Imunoglobulina/genética , Imunoterapia/métodos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêuticoRESUMO
Biomarkers in chronic lymphocytic leukemia (CLL) allow assessment of prognosis. However, the validity of current prognostic biomarkers based on a single assessment point remains unclear for patients who have survived one or more years. Conditional survival (CS) studies that address how prognosis may change over time, especially in prognostic subgroups, are still rare. We performed CS analyses to estimate 5-year survival in 1-year increments, stratified by baseline disease characteristics and known risk factors in two community-based cohorts of CLL patients (Freiburg University Hospital (n = 316) and Augsburg University Hospital (n = 564)) diagnosed between 1984 and 2021. We demonstrate that 5-year CS probability is stable (app. 75%) for the entire CLL patient cohort over 10 years. While age, sex, and stage have no significant impact on CS, patients with high-risk disease features such as non-mutated IGHV, deletion 17p, and high-risk CLL-IPI have a significantly worse prognosis at diagnosis, and 5-year CS steadily decreases with each additional year survived. Our results confirm that CLL patients have a stable survival probability with excess mortality and that the prognosis of high-risk CLL patients declines over time. We infer that CS-based prognostic information is relevant for disease management and counseling of CLL patients.
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Leucemia Linfocítica Crônica de Células B , Humanos , Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/terapia , Prognóstico , Biomarcadores , Análise de Sobrevida , MutaçãoRESUMO
The aim of the current study was to assess the associations between genetic risk factors (such as the mutational status of the IGHV gene and polymorphisms of the IL-10 and TNF-α genes) and CLL risk, prognosis, and overall survival. Another goal of this study was to evaluate the multivariate effect of the combination of multiple genetic risk factors (mutational status of the IGHV gene, somatic mutations, DNA CNVs, and cytokine SNPs) on the clinical characteristics and survival of patients. A total of 125 CLL patients and 239 healthy controls were included for comparative SNP analysis. IL-10 (rs1800896 and rs1800872) and TNF-α (rs361525 and rs1800750) SNPs and haplotypes were not associated with CLL risk. The absence of hypermutation in the IGHV gene was shown to be of important prognostic value, being associated with short OS. Further individual risk factors for short OS were an age above 65 years at diagnosis and the presence of somatic mutations and/or CNVs. In our multivariable analysis, the presence of somatic mutations and the IL-10 rs1800872 variant allele, and the association of CNVs with the IL-10 rs1800896 variant allele, were identified as risk factors for short OS. Moreover, the OS in unmutated IGHV patients was additionally affected (decreased) by the presence of CNVs and/or somatic mutations. Similarly, IL-10 rs1800896 modulated the OS in unmutated IGHV patients with CNVs.
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Leucemia Linfocítica Crônica de Células B , Humanos , Idoso , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/diagnóstico , Região Variável de Imunoglobulina/genética , Interleucina-10/genética , Citocinas/genética , Fator de Necrose Tumoral alfa/genética , Prognóstico , Romênia , MutaçãoRESUMO
Chronic lymphocytic leukemia (CLL) is the most common leukemia in adults. One of the best established CLL prognostic markers is the somatic hypermutational status of the IGHV gene which is a part of the immunoglobulin heavy chain variable region. Technology for IGHV genotyping has been optimized and has been applied in routine diagnostics for the first time in Bulgaria. A total of 105 patients with CLL from different Bulgarian regions were tested. IGHV mutational status was determined by Sanger sequencing on total genomic DNA (gDNA) or RNA extracted from mononuclear cells. All sequencing profiles were analyzed with the IMGT/V-QUEST tool. Within the course of the analysis a high percentage of IGHV unmutated status was established in the Varna district on the Black Sea (Northeast Bulgaria). In addition, the IGHV genotyping performed on gDNA revealed a rare case with multiple rearrangements. The present data from IGHV genotyping will help in choosing the proper treatment for the benefit of Bulgarian CLL patients.
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With its heterogeneous biological features and clinical course, chronic lymphocytic leukemia (CLL), the most frequent adult leukemia in the Western world, is a paradigmatic condition requiring a tailored approach and a precise knowledge of the biology behind each individual patient. This personalized management is becoming even more crucial, since, after decades of preclinical work unravelling the key role of the B-cell receptor (BcR) signalling pathways and the anti-apoptotic mechanisms in CLL cell survival and proliferation, we have now BcR and BCL2 inhibitors available in clinical practice. Thanks to this, we are now able to exploit specific biomarkers to tailor our treatment strategies and improve long-term disease control, patient outcome and quality of life. That notwithstanding, as the disease itself remains incurable, novel challenges and unmet clinical needs have risen from the introduction of novel targeted agents, including mechanisms of resistance at both genetic and epigenetic levels. In this review, we summarize the currently established predictive biomarkers (i.e. IGHV mutation status and TP53 gene disruption) that should be applied in clinical practice to inform treatment decision in 2021 but also discuss the most promising prognostic biomarkers (B-cell receptor stereotypy, complex karyotype, somatic gene mutations, measurable residual disease - MRD) that might become key to define the management of our patients in a near future.
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Antineoplásicos , Leucemia Linfocítica Crônica de Células B , Adulto , Antineoplásicos/uso terapêutico , Humanos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/genética , Mutação , Prognóstico , Qualidade de Vida , Receptores de Antígenos de Linfócitos B/genéticaRESUMO
Although monoclonal antibodies to the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) are known, B-cell receptor repertoire and its change in patients during coronavirus disease-2019 (COVID-19) progression is underreported. We aimed to study this molecularly. We used immunoglobulin heavy chain (IGH) variable region (IGHV) spectratyping and next-generation sequencing of peripheral blood B-cell genomic DNA collected at multiple time points during disease evolution to study B-cell response to SARS-CoV-2 infection in 14 individuals with acute COVID-19. We found a broad distribution of responding B-cell clones. The IGH gene usage was not significantly skewed but frequencies of individual IGH genes changed repeatedly. We found predominant usage of unmutated and low mutation-loaded IGHV rearrangements characterizing naïve and extrafollicular B cells among the majority of expanded peripheral B-cell clonal lineages at most tested time points in most patients. IGH rearrangement usage showed no apparent relation to anti-SARS-CoV-2 antibody titers. Some patients demonstrated mono/oligoclonal populations carrying highly mutated IGHV rearrangements indicating antigen experience at some of the time points tested, including even before anti-SARS-CoV-2 antibodies were detected. We present evidence demonstrating that the B-cell response to SARS-CoV-2 is individual and includes different lineages of B cells at various time points during COVID-19 progression.
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COVID-19 , Genes de Imunoglobulinas , Humanos , COVID-19/genética , SARS-CoV-2/genética , Receptores de Antígenos de Linfócitos B/genética , Linfócitos B , Anticorpos AntiviraisRESUMO
Fluorescence in situ hybridization (FISH) to detect the recurrent cytogenetics abnormalities deletion 13q, trisomy 12, deletion 11q, and deletion 17p is important for prognostication in chronic lymphocytic leukemia (CLL). A subset of patients are negative for each of these abnormalities (normal 12/13/11/17 FISH), and outcomes are heterogenous within this group. To elucidate variables important for prognostication in this subgroup we conducted a retrospective analysis of 280 treatment-naïve CLL patients with normal standard CLL FISH results. In a multivariable model, advanced Rai stage (p = 0.04, hazard ratio [HR] 1.24 (95% confidence interval [CI] 1.01-1.53)), unmutated immunoglobulin heavy chain gene (IGHV) (p < 0.0001, HR 5.59 (95% CI 3.63-8.62)) and IGH rearrangement by FISH (p = 0.02, HR 2.56 (95% CI 1.20-5.48)) were significantly associated with shorter time to first treatment. In a multivariable model for overall survival, increasing age at 5-year increments (p < 0.0001, HR 1.55 (95% CI 1.25-1.93)), unmutated IGHV (p = 0.01, HR 5.28 (95% CI 1.52-18.35)) and gain of REL (p = 0.01, HR 4.08 (5% CI 1.45-11.49)) were significantly associated with shorter survival. Our study identifies variables important for refining prognosis for CLL patients with normal standard CLL FISH results.
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Leucemia Linfocítica Crônica de Células B , Humanos , Pré-Escolar , Hibridização in Situ Fluorescente/métodos , Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/genética , Estudos Retrospectivos , Aberrações Cromossômicas , PrognósticoRESUMO
Chronic lymphocytic leukemia can evolve to an aggressive lymphoma-in most of the cases diffuse large B cells lymphoma, rarely Hodgkin lymphoma-and this complication is defined Richter syndrome (RS). Immunogenotypic features that characterize RS include unmutated IgHV status with high prevalence of IgHV4-39/D6-13/J5 sequence; deletion of chromosome 17p or 11q; activation of oncogenes as NOTCH1 and c-MYC; inactivation of onco-suppressors as TP53 and CDKN2A; high expression of CD38 in lymph-nodes. The prognosis of this condition is very poor: patients experience a rapid clinical deterioration with frequent therapeutic failure since the current options include suboptimal strategies as standard chemo-immunotherapy followed by hematopoietic stem cells transplantation or enrollment in clinical trials which investigate the efficacy of target drugs. Understanding the biology of such a heterogeneous condition is crucial to personalize the treatment and improve patient's survival.
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Doença de Hodgkin , Leucemia Linfocítica Crônica de Células B , Linfoma Difuso de Grandes Células B , Humanos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Prognóstico , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Doença de Hodgkin/patologia , Transformação Celular Neoplásica/genéticaRESUMO
Aim: Chronic lymphocytic leukemia (CLL) is a highly heterogenous hemopathy. Genetic stratification of CLL patients has important prognostic and therapeutic values - mainly immunoglobulin heavy chain variable region gene (IGHV) mutational status and the presence of cytogenetic abnormalities. The genetics of CLL in Lebanon is scarcely described in the literature. Patients & methods: In this work, we studied the genetic biomarkers of 312 Lebanese CLL patients. Results: Prominent IGHV genes were IGHV4-34, IGHV1-69 and IGHV3-30; and CLL #1 and #5 presented major subsets. Some similarities as well as major differences were highlighted when comparing our data with previously published data. Conclusion: The distribution of IGHV alleles in our series differed from previously described distributions, suggesting involvement of antigenic selection and regional variables in CLL pathogenesis.
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Leucemia Linfocítica Crônica de Células B , Humanos , Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/epidemiologia , Leucemia Linfocítica Crônica de Células B/genética , Estudos Retrospectivos , Marcadores Genéticos , Genes de Cadeia Pesada de Imunoglobulina/genética , Líbano/epidemiologia , Região Variável de Imunoglobulina/genética , Prognóstico , MutaçãoRESUMO
Chronic lymphocytic leukemia (CLL) is the most common adult leukemia in Western countries. However, CLL is relatively rare in Asia; its genetic features are rarely studied. Here, we aimed to genetically characterize Korean CLL patients and to elucidate the genetic and clinical associations based on data obtained from 113 patients at a single Korean institute. We used next-generation sequencing to explore the multi-gene mutational data and immunoglobulin heavy chain variable gene clonality with somatic hypermutation (SHM). MYD88 (28.3%), including L265P (11.5%) and V217F (13.3%), was the most frequently mutated gene, followed by KMT2D (6.2%), NOTCH1 (5.3%), SF3B1 (5.3%), and TP53 (4.4%). MYD88-mutated CLL was characterized by SHM and atypical immunophenotype with fewer cytogenetic abnormalities. The 5-year time to treatment (TTT) of the overall cohort was 49.8% ± 8.2% (mean ± standard deviation) and the 5-year overall survival was 86.2% ± 5.8%. Patients with SHM, isolated del(13q), TP53-wild type, and NOTCH1-wild type showed better results than those without these conditions. In the subgroup analyses, patients with SHM and L265P presented shorter TTT than patients with SHM but not L265P. In contrast, V217F was associated with a higher SHM percentage and showed a favorable prognosis. Our study revealed the distinct characteristics of Korean CLL patients with high frequencies of MYD88 mutations and their clinical relevance.
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Leucemia Linfocítica Crônica de Células B , Adulto , Humanos , Aberrações Cromossômicas , Leucemia Linfocítica Crônica de Células B/genética , Mutação , Fator 88 de Diferenciação Mieloide/genética , República da CoreiaRESUMO
INTRODUCTION: The Chronic Lymphocytic Leukemia International Prognostic Index (CLL-IPI) is a powerful prognostic tool validated in multiple Western populations. However, its utility in the young Middle Eastern population is unknown. METHODOLOGY: We conducted a retrospective analysis of 152 unselected patients with chronic lymphocytic leukemia (CLL) diagnosed between 2008 and 2022 at the Kuwait Cancer Control Center, which serves as the sole cancer center in Kuwait. The evaluation of the CLL-IPI was based on the assessment of event-free survival (EFS) across the entire cohort. Subsequently, we compared the CLL-IPI with the International Prognostic Score for Early-stage patients (IPS-E) in order to predict the time to first treatment specifically within the subgroup of patients diagnosed with early-stage disease. RESULTS: The median age of the study cohort was 59.9 years (IQR, 53.1-68.8). The 5-year EFS rates for the low, intermediate, and high/very high-risk categories were approximately 82%, 34%, and 23%, respectively, p < 0.001 (C-statistic = 0.67). On multivariate analysis, advanced stage and unmated IGHV status were independent prognostic factors of EFS. In those with early-stage disease, cumulative 5-year treatment incidence rates for the low, intermediate, and high/very high-risk categories based on the CLL-IPI score were approximately 8%, 55%, and 55%, respectively, p = 0.001 (C-statistic = 0.70). However, based on the IPS-E score, the cumulative 5-year treatment incidence rates for the low, intermediate, and high-risk categories were approximately 0%, 10%, and 60%, respectively, p < 0.001 (C-statistic = 0.73). CONCLUSIONS: The CLL-IPI and the IPS-E are valid stratification tool in our young Middle Eastern population.
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Leucemia Linfocítica Crônica de Células B , Humanos , Pessoa de Meia-Idade , Idoso , Prognóstico , Estudos Retrospectivos , Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/epidemiologia , Kuweit/epidemiologiaRESUMO
Richter syndrome (RS) is mostly due to the direct transformation of the chronic lymphocytic leukaemia (CLL) clone, as documented by the same immunoglobulin heavy-chain variable region (IGHV) rearrangement in both CLL and RS cells. In rare cases characterized by a better outcome, the RS clone harbours a different IGHV rearrangement compared to the CLL phase. We investigated the CLL phase of clonally unrelated RS to test whether the RS clone was already identifiable prior to clinicopathologic transformation, albeit undetectable by conventional approaches. CLL cells of eight patients with unrelated RS were subjected to an ultra-deep next-generation sequencing (NGS) approach with a sensitivity of 10-6 . In 7/8 cases, the RS rearrangement was not identified in the CLL phase. In one case, the RS clone was identified at a very low frequency in the CLL phase, conceivably due to the concomitance of CLL sampling and RS diagnosis. Targeted resequencing revealed that clonally unrelated RS carries genetic lesions primarily affecting the TP53, MYC, ATM and NOTCH1 genes. Conversely, mutations frequently involved in de novo diffuse large B-cell lymphoma (DLBCL) without a history of CLL were absent. These results suggest that clonally unrelated RS is a truly de novo lymphoma with a mutational profile reminiscent, at least in part, of clonally related RS.
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Leucemia Linfocítica Crônica de Células B , Linfoma Difuso de Grandes Células B , Aberrações Cromossômicas , Humanos , Região Variável de Imunoglobulina/genética , Leucemia Linfocítica Crônica de Células B/patologia , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/patologia , MutaçãoRESUMO
Chronic lymphocytic leukemia (CLL) is the most common mature B-cell neoplasm in the West. IGHV4-34 is one of the most frequently used genes in CLL patients, which usually display an indolent outcome. In this study, we explored the mutational profile of CLL patients expressing IGHV4-34 within different stereotypes and their association with prognostic factors and clinical outcome. A multi-institutional cohort of unselected 1444 CLL patients was analyzed by RT-PCR and bidirectional sequencing. Cytogenetics and molecular cytogenetics analyses were also performed. We identified 144 (10%) IGHV4-34 expressing cases, 119 mutated (M), 44 of them with stereotyped B-cell receptors. Subset #4 was the most frequent (56.8% of cases) followed by subsets #16 (13.6%), #29 (6.8%), and #201 (2.3%), with different distribution among countries. Analysis of somatic hypermutation profile showed significant differences among stereotyped subsets for G28>D/E, P45>S, E55>Q, and S64>I changes (p < 0.01) and high frequency of disruption of the glycosylation motif in the VH CDR2 region. All stereotyped IGHV4-34 cases showed normal karyotypes. Deletion 13q14 as a sole alteration was present in 42.8% of stereotyped cases with a different distribution among subsets. A shorter time to first treatment was found in non-stereotyped vs. stereotyped M-IGHV4-34 patients (p = 0.034). Our results add new information supporting the importance of recurrent amino acid changes at particular positions, contributing to refine the molecular characterization of South American CLL patients.
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Cadeias Pesadas de Imunoglobulinas/genética , Leucemia Linfocítica Crônica de Células B/genética , Idoso , Estudos de Coortes , Feminino , Rearranjo Gênico , Humanos , Leucemia Linfocítica Crônica de Células B/epidemiologia , Masculino , Pessoa de Meia-Idade , Mutação , Receptores de Antígenos de Linfócitos B/genética , Hipermutação Somática de Imunoglobulina , América do Sul/epidemiologiaRESUMO
BACKGROUND: Chromosomal abnormalities and gene mutations determine the prognosis of patients with chronic lymphocytic leukemia (CLL). Genetic lesions can be acquired by clonal evolution (CE) likely correlating with clinical progression. METHODS AND RESULTS: Samples of 169 CLL patients were analyzed for cytogenetic clonal evolution (CCE) and CE affecting the genes TP53 and SF3B1. Moreover, the mutational status of IGHV and the clinical outcome was evaluated. CCE was observed in 35% of CLL patients. The most frequently gained cytogenetic aberration was a deletion of TP53. Acquired TP53 deletion was more frequent in patients with SF3B1 mutations compared to those without (19% vs. 7%). CCE showed a tendency to occur more frequently in patients with an aberrant karyotype at first investigation than in patients with a normal karyotype. In 73% of patients with CCE (p = 0.002) and 92% of patients with CE affecting the genes TP53 and SF3B1 (p < 0.001) an unmutated IGHV status was present. CCE and CE affecting the genes TP53 and SF3B1 were significantly associated with each other (p < 0.001). In 7% of patients, CE resulted in the co-occurrence of TP53 deletion and TP53 mutation resulting in a significantly shorter overall survival. CONCLUSIONS: The most frequently gained cytogenetic aberration during CCE was a deletion of TP53, which was associated with SF3B1 mutations. Moreover, CCE was associated with an unmutated IGHV status. Our results indicate the importance of re-evaluation of the TP53 status during the course of the disease to ensure correct treatment guidance.
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Leucemia Linfocítica Crônica de Células B , Humanos , Leucemia Linfocítica Crônica de Células B/genética , Proteína Supressora de Tumor p53/genética , Mutação/genética , Aberrações Cromossômicas , Evolução Clonal/genéticaRESUMO
Composite lymphoma is the rare simultaneous manifestation of two distinct lymphomas. Chronic lymphocytic leukemia (CLL) has a propensity for occurring in composite lymphomas, a phenomenon that remains to be elucidated. We applied cytogenetics, droplet digital polymerase chain reaction, and massively parallel sequencing to analyze longitudinally a patient with CLL, who 3 years later showed transformation to a hairy cell leukemia-variant (HCL-V). Outgrowth of the IGHV4-34-positive HCL-V clone at the expense of the initially dominant CLL clone with trisomy 12 and MED12 mutation started before CLL-guided treatment and was accompanied by a TP53 mutation, which was already detectable at diagnosis of CLL. Furthermore, deep sequencing of IGH showed a composite lymphoma with presence of both disease components at all analyzed timepoints (down to a minor clone: major clone ratio of ~1:1000). Overall, our analyses showed a disease course that resembled clonal dynamics reported for malignancies with intratumoral heterogeneity and illustrate the utility of deep sequencing of IGH to detect distinct clonal populations at diagnosis, monitor clonal response to therapy, and possibly improve clinical outcomes.
Assuntos
Células Clonais , Leucemia de Células Pilosas/patologia , Leucemia Linfocítica Crônica de Células B/patologia , Neoplasias Primárias Múltiplas/patologia , Idoso , Cromossomos Humanos Par 12 , Genes de Cadeia Pesada de Imunoglobulina , Humanos , Leucemia Linfocítica Crônica de Células B/genética , Masculino , Neoplasias Primárias Múltiplas/genética , Reação em Cadeia da Polimerase , Trissomia , Sequenciamento Completo do GenomaRESUMO
The manageable toxicity profile of obinutuzumab (GA101; G) alone or with chemotherapy in first-line (1L; fit and non-fit) and relapsed/refractory (R/R) patients with chronic lymphocytic leukaemia (CLL) was established in the primary analysis of the Phase IIIb GREEN trial (Clinicaltrials.gov: NCT01905943). The final analysis (cut-off, 31 January 2019) is reported here. Patients received G (1000 mg) alone (G-mono; fit and non-fit patients) or with chemotherapy [fludarabine and cyclophosphamide (FC; fit patients); chlorambucil (non-fit patients); bendamustine (any patient)]. Study endpoints were safety (primary) and efficacy (secondary). Subgroup analyses were performed on prognostic biomarkers in 1L CLL. Overall, 630 patients received 1L and 341 received R/R CLL treatment. At the final analysis, no new safety signals were observed [Grade ≥ 3 adverse events (AEs): 1L 82·7%, R/R 84·5%; serious AEs: 1L 58·1%, R/R 62·5%]. Neutropenia (1L 50·5%, R/R 53·4%) and thrombocytopenia (1L 14·6%, R/R 19·1%) were the most common Grade 3-5 AEs. G-mono-, G-bendamustine and G-FC-treated patients with unmutated immunoglobulin heavy chain trended towards shorter progression-free survival. Achievement of minimal residual disease negativity was greatest in 1L patients treated with G-FC. In this final analysis of the GREEN trial, the safety profile of G was consistent with current risk management strategies. Biomarker analyses supported efficacy in the specific subgroups.