RESUMO
In the microenvironment, cell interactions are established between different cell types to regulate their migration, survival and activation. ß-Catenin is a multifunctional protein that stabilizes cell-cell interactions and regulates cell survival through its transcriptional activity. We used chronic lymphocytic leukemia (CLL) cells as a cellular model to study the role of ß-catenin in regulating the adhesion of tumor cells to their microenvironment, which is necessary for tumor cell survival and accumulation. When co-cultured with a stromal cell line (HS-5), a fraction of the CLL cells adhere to stromal cells in a dynamic fashion regulated by the different levels of ß-catenin expression. In non-adherent cells, ß-catenin is stabilized in the cytosol and translocates into the nucleus, increasing the expression of cyclin D1. In adherent cells, the level of cytosolic ß-catenin is low but membrane ß-catenin helps to stabilize the adhesion of CLL to stromal cells. Indeed, the overexpression of ß-catenin enhances the interaction of CLL with HS-5 cells, suggesting that this protein behaves as a regulator of cell adhesion to the stromal component and of the transcriptional regulation of cell survival. Inhibitors that block the stabilization of ß-catenin alter this equilibrium and effectively disrupt the support that CLL cells receive from the cross-talk with the stroma.
Assuntos
Tirosina Quinase da Agamaglobulinemia , Leucemia Linfocítica Crônica de Células B , beta Catenina , Humanos , beta Catenina/genética , beta Catenina/metabolismo , Comunicação Celular , Linhagem Celular Tumoral , Leucemia Linfocítica Crônica de Células B/patologia , Células Estromais/metabolismo , Microambiente Tumoral , Tirosina Quinase da Agamaglobulinemia/metabolismoRESUMO
Mutational analyses performed following acquired ibrutinib resistance have suggested that chronic lymphocytic leukemia (CLL) progression on ibrutinib is linked to mutations in Bruton tyrosine kinase (BTK) and/or phospholipase Cγ2 (PLCG2) genes. Mutational information for patients still on ibrutinib is limited. We report a study aimed to provide a "snapshot" of the prevalence of mutations in a real-life CLL cohort still on ibrutinib after at least 3 years of treatment. Of 204 patients who initiated ibrutinib via an early-access program at 29 French Innovative Leukemia Organization (FILO) centers, 63 (31%) were still on ibrutinib after 3 years and 57 provided a fresh blood sample. Thirty patients had a CLL clone ≥0.5 × 109/L, enabling next-generation sequencing (NGS); BTK and PLCG2 mutations were detected in 57% and 13% of the NGS samples, respectively. After median follow-up of 8.5 months from sample collection, the presence of a BTK mutation was significantly associated with subsequent CLL progression (P = .0005 vs no BTK mutation). Our findings support that mutational analysis should be considered in patients receiving ibrutinib who have residual clonal lymphocytosis, and that clinical trials are needed to evaluate whether patients with a BTK mutation may benefit from an early switch to another treatment.
Assuntos
Tirosina Quinase da Agamaglobulinemia/genética , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Fosfolipase C gama/genética , Inibidores de Proteínas Quinases/uso terapêutico , Pirazóis/uso terapêutico , Pirimidinas/uso terapêutico , Adenina/análogos & derivados , Tirosina Quinase da Agamaglobulinemia/antagonistas & inibidores , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Feminino , Seguimentos , Humanos , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/patologia , Masculino , Pessoa de Meia-Idade , Mutação , PiperidinasAssuntos
Vacinas contra COVID-19/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Hemólise , Icterícia/etiologia , Neoplasias Pulmonares/tratamento farmacológico , Vicia faba/efeitos adversos , Idoso , Anticorpos Monoclonais/uso terapêutico , Transfusão de Sangue , Carcinoma Pulmonar de Células não Pequenas/sangue , Carcinoma Pulmonar de Células não Pequenas/complicações , Diagnóstico Diferencial , Deficiência de Glucosefosfato Desidrogenase/complicações , Humanos , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/complicações , Masculino , Vacinação/efeitos adversosAssuntos
Clorambucila , Leucemia Linfocítica Crônica de Células B , Proteína Supressora de Tumor p53 , Clorambucila/uso terapêutico , Códon , Humanos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/genética , Mutação , Proteína Supressora de Tumor p53/genéticaRESUMO
TP53 abnormalities lead to resistance to purine analogues and are found in over 40% of patients with refractory chronic lymphocytic leukemia (CLL). At diagnosis, no more than 5% of patients carry the 17p deletion, most cases harbour mutations within the other TP53 allele. The incidence of a TP53 mutation as the only alteration is approximately 5%, but this depends on the sensitivity of the technique. Recently, having a complex karyotype has been considered a strong adverse prognostic factor. However, there are no longitudinal studies simultaneously examining the presence of the 17p deletion, TP53 mutations and karyotype abnormalities. We conducted a retrospective longitudinal study of 31 relapsed/refractory CLL patients. Two to six blood samples per patient were analyzed, with a median follow-up of 8 years. In this report, we assessed the sequence of events of TP53 clonal evolution and correlated the presence of TP53 abnormalities to genetic instability during progression and treatment. Next-generation sequencing allowed the early detection of TP53 mutated clones and was able to be performed on a routine basis, demonstrating an excellent correlation between the Illumina and Ion Torrent technologies. We concluded that TP53 mutations are early events and precede clonal evolution to complex karyotypes. We strongly recommend the early and iterated detection of TP53 mutations in progressive cases.
Assuntos
Genes p53 , Leucemia Linfocítica Crônica de Células B/genética , Mutação , Proteína Supressora de Tumor p53/genética , Progressão da Doença , Humanos , Hibridização in Situ Fluorescente , Cariótipo , Leucemia Linfocítica Crônica de Células B/sangue , Leucemia Linfocítica Crônica de Células B/patologia , Estudos Longitudinais , Estudos RetrospectivosAssuntos
Linfoma Difuso de Grandes Células B/genética , Mutação , Análise Citogenética , Progressão da Doença , França/epidemiologia , Humanos , Linfoma Difuso de Grandes Células B/diagnóstico , Linfoma Difuso de Grandes Células B/epidemiologia , Linfoma Difuso de Grandes Células B/patologia , Prognóstico , Análise de SobrevidaAssuntos
Leucemia Linfocítica Crônica de Células B/patologia , Neoplasias Cutâneas/patologia , Pele/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Linfócitos B/patologia , Feminino , França/epidemiologia , Humanos , Leucemia Linfocítica Crônica de Células B/epidemiologia , Leucemia Linfocítica Crônica de Células B/genética , Masculino , Pessoa de Meia-Idade , Mutação , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/genética , Resultado do TratamentoRESUMO
Several studies provide evidences for mantle cell lymphoma (MCL) cell survival relying on B-cell receptor (BCR)-mediated signalling pathways, whereas the nature of this activation is unknown. Significant progress in MCL treatment is achieved through therapies targeting BCR-associated kinases, i.e., Ibrutinib and Fostamatinib, inhibitors of BTK and SYK, respectively. Our study addresses survival signals emanating from the BCR or the tumour environment and how inhibiting BCR signalling effectors might impact these survival signals. We found that BTK was constitutively activated and that SYK phosphorylation was highly increased and sustained upon BCR activation of primary MCL cells. Moreover, MCL cells from leukaemic patients secreted high amount of IL-1ß, IL-6, IL-8 and CCL5. Activation of the BCR induced (i) cell survival, (ii) STAT3 activation and (iii) increased autocrine secretion of IL-1ß, IL-6, IL-8, CCL5, IL-10, TNFα and VEGF. Specific inhibition of BTK by Ibrutinib or SYK by Fostamatinib (R406) reversed these protective effects and decreased both basal and BCR-induced autocrine cytokine secretions associated with STAT3 phosphorylation. Interestingly, targeting BTK and SYK prevented and inhibited BCR-induced MCL cell adhesion to human bone marrow stromal cells (HMSCs) in short- and long-term co-culture. We demonstrated that BCR-induced survival relies on autocrine secretion of IL-1ß, TNFα and CCL5 that might facilitate adhesion of MCL cells to HMSC. Treatment with Ibrutinib or Fostamatinib blocked the chemotactic signal thus increasing apoptosis.
Assuntos
Oxazinas/farmacologia , Pirazóis/farmacologia , Piridinas/farmacologia , Pirimidinas/farmacologia , Receptores de Antígenos de Linfócitos B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Adenina/análogos & derivados , Tirosina Quinase da Agamaglobulinemia , Idoso , Idoso de 80 Anos ou mais , Aminopiridinas , Apoptose/efeitos dos fármacos , Western Blotting , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Técnicas de Cocultura , Citocinas/genética , Feminino , Expressão Gênica/efeitos dos fármacos , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Linfoma de Célula do Manto/genética , Linfoma de Célula do Manto/metabolismo , Linfoma de Célula do Manto/patologia , Masculino , Pessoa de Meia-Idade , Morfolinas , Fosforilação/efeitos dos fármacos , Piperidinas , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Quinase Syk , Células Tumorais CultivadasAssuntos
Anemia Hemolítica Autoimune , Betacoronavirus , Infecções por Coronavirus , Pandemias , Pneumonia Viral , Idoso , Anemia Hemolítica Autoimune/epidemiologia , Anemia Hemolítica Autoimune/etiologia , Anemia Hemolítica Autoimune/terapia , COVID-19 , Infecções por Coronavirus/complicações , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pneumonia Viral/complicações , Pneumonia Viral/epidemiologia , Pneumonia Viral/terapia , SARS-CoV-2Assuntos
Carioferinas/genética , Leucemia Linfocítica Crônica de Células B/epidemiologia , Leucemia Linfocítica Crônica de Células B/genética , Mutação , Receptores Citoplasmáticos e Nucleares/genética , Alelos , Biomarcadores Tumorais , Evolução Clonal , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/mortalidade , Prevalência , Prognóstico , Proteína Exportina 1RESUMO
Richter transformation (RT) is an aggressive lymphoma occurring in patients with chronic lymphocytic leukaemia. Here we investigated the anti-CD3/anti-CD19 T-cell-engager blinatumomab after R-CHOP (i.e. rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) in patients with untreated RT of diffuse large B-cell lymphoma histology (NCT03931642). In this multicentre phase 2 study, patients without complete response (CR) after two cycles of R-CHOP were eligible to receive an 8-week blinatumomab induction via continuous vein infusion with stepwise dosing until 112 µg/day. The primary endpoint was the CR rate after blinatumomab induction and secondary endpoint included safety, response duration, progression-free and overall survival. Thirty-nine patients started the first cycle of R-CHOP, 25 of whom received blinatumomab. After blinatumomab induction, five (20%) patients achieved CR, four (16%) achieved partial response, and six (24%) were stable. Considering the entire strategy, the overall response rate in the full-analysis-set was 46% (n = 18), with CR in 14 (36%) patients. The most common treatment-emergent adverse events of all grades in the blinatumomab-safety-set included fever (36%), anaemia (24%), and lymphopaenia (24%). Cytokine release syndrome (grade 1/2) was observed in 16% and neurotoxicity in 20% of patients. Blinatumomab demonstrated encouraging anti-tumour activity (the trial met its primary endpoint) and acceptable toxicity in patients with RT.
Assuntos
Anticorpos Biespecíficos , Protocolos de Quimioterapia Combinada Antineoplásica , Ciclofosfamida , Doxorrubicina , Linfoma Difuso de Grandes Células B , Prednisona , Rituximab , Vincristina , Humanos , Masculino , Feminino , Anticorpos Biespecíficos/administração & dosagem , Anticorpos Biespecíficos/efeitos adversos , Anticorpos Biespecíficos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Pessoa de Meia-Idade , Ciclofosfamida/uso terapêutico , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Rituximab/administração & dosagem , Rituximab/uso terapêutico , Rituximab/efeitos adversos , Doxorrubicina/uso terapêutico , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Idoso , Prednisona/uso terapêutico , Prednisona/administração & dosagem , Prednisona/efeitos adversos , Vincristina/uso terapêutico , Vincristina/efeitos adversos , Vincristina/administração & dosagem , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Adulto , Idoso de 80 Anos ou mais , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Resultado do TratamentoRESUMO
Richter syndrome (RS) is the transformation of chronic lymphocytic leukemia (CLL) into aggressive lymphoma, most commonly diffuse large B-cell lymphoma (DLBCL). We characterize 58 primary human RS samples by genome-wide DNA methylation and whole-transcriptome profiling. Our comprehensive approach determines RS DNA methylation profile and unravels a CLL epigenetic imprint, allowing CLL-RS clonal relationship assessment without the need of the initial CLL tumor DNA. DNA methylation- and transcriptomic-based classifiers were developed, and testing on landmark DLBCL datasets identifies a poor-prognosis, activated B-cell-like DLBCL subset in 111/1772 samples. The classification robustly identifies phenotypes very similar to RS with a specific genomic profile, accounting for 4.3-8.3% of de novo DLBCLs. In this work, RS multi-omics characterization determines oncogenic mechanisms, establishes a surrogate marker for CLL-RS clonal relationship, and provides a clinically relevant classifier for a subset of primary "RS-type DLBCL" with unfavorable prognosis.
Assuntos
Leucemia Linfocítica Crônica de Células B , Linfoma Difuso de Grandes Células B , Humanos , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/patologia , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/patologia , Linfócitos B/patologia , Metilação de DNA/genéticaRESUMO
In chronic lymphocytic leukemia (CLL), TP53 abnormalities are associated with reduced survival and resistance to chemoimmunotherapy (CIT). The recommended threshold to clinically report TP53 mutations is a matter of debate given that next-generation sequencing technologies can detect mutations with a limit of detection of approximately 1% with high confidence. However, the clinical impact of low-burden TP53 mutations with a variant allele frequency (VAF) of less than 10% remains unclear. Longitudinal analysis before and after fludarabine based on NGS sequencing demonstrated that low-burden TP53 mutations were present before the onset of treatment and expanded at relapse to become the predominant clone. Most studies evaluating the prognostic or predictive impact of low-burden TP53 mutations in untreated patients show that low-burden TP53 mutations have the same unfavorable prognostic impact as clonal defects. Moreover, studies designed to assess the predictive impact of low-burden TP53 mutations showed that TP53 mutations, irrespective of mutation burden, have an inferior impact on overall survival for CIT-treated patients. As low-burden and high-burden TP53 mutations have comparable clinical impacts, redefining the VAF threshold may have important implications for the clinical management of CLL.
RESUMO
Hotspot mutation of IKZF3 (IKZF3-L162R) has been identified as a putative driver of chronic lymphocytic leukemia (CLL), but its function remains unknown. Here, we demonstrate its driving role in CLL through a B cell-restricted conditional knockin mouse model. Mutant Ikzf3 alters DNA binding specificity and target selection, leading to hyperactivation of B cell receptor (BCR) signaling, overexpression of nuclear factor κB (NF-κB) target genes, and development of CLL-like disease in elderly mice with a penetrance of ~40%. Human CLL carrying either IKZF3 mutation or high IKZF3 expression was associated with overexpression of BCR/NF-κB pathway members and reduced sensitivity to BCR signaling inhibition by ibrutinib. Our results thus highlight IKZF3 oncogenic function in CLL via transcriptional dysregulation and demonstrate that this pro-survival function can be achieved by either somatic mutation or overexpression of this CLL driver. This emphasizes the need for combinatorial approaches to overcome IKZF3-mediated BCR inhibitor resistance.
Assuntos
Linfócitos B/patologia , Fator de Transcrição Ikaros/genética , Leucemia Linfocítica Crônica de Células B/genética , Mutação/genética , Transcrição Gênica/genética , Animais , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , NF-kappa B/genética , Receptores de Antígenos de Linfócitos B/genética , Transdução de Sinais/genéticaRESUMO
B-cell receptor (BCR) signaling pathways and interactions with the tumor microenvironment account for mantle cell lymphoma (MCL) cells survival in lymphoid organs. In several MCL cases, the WNT/ß-catenin canonical pathway is activated and ß-catenin accumulates into the nucleus. As both BCR and ß-catenin are important mediators of cell survival and interaction with the microenvironment, we investigated the crosstalk between BCR and WNT/ß-catenin signaling and analyzed their impact on cellular homeostasis as well as their targeting by specific inhibitors. ß-catenin was detected in all leukemic MCL samples and its level of expression rapidly increased upon BCR stimulation. This stabilization was hampered by the BCR-pathway inhibitor Ibrutinib, supporting ß-catenin as an effector of the BCR signaling. In parallel, MCL cells as compared with normal B cells expressed elevated levels of WNT16, a NF-κB target gene. Its expression increased further upon BCR stimulation to participate to the stabilization of ß-catenin. Upon BCR stimulation, ß-catenin translocated into the nucleus but did not induce a Wnt-like transcriptional response, i.e., TCF/LEF dependent. ß-catenin rather participated to the regulation of NF-κB transcriptional targets, such as IL6, IL8, and IL1. Oligo pull down and chromatin immunoprecipitation experiments demonstrated that ß-catenin is part of a protein complex that binds the NF-κB DNA consensus sequence, strengthening the idea of an association between the two proteins. An inhibitor targeting ß-catenin transcriptional interactions hindered both NF-κB DNA recruitment and induced primary MCL cells apoptosis. Thus, ß-catenin likely represents another player through which BCR signaling impacts on MCL cell survival.
Assuntos
Linfoma de Célula do Manto/genética , NF-kappa B/genética , Receptores de Antígenos de Linfócitos B/genética , Transcrição Gênica/genética , Via de Sinalização Wnt/genética , beta Catenina/genética , Animais , Apoptose/genética , Linfócitos B/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Núcleo Celular/genética , Sobrevivência Celular/genética , Feminino , Células HEK293 , Homeostase/genética , Humanos , Camundongos , Fatores de Transcrição TCF/genética , Microambiente Tumoral/genéticaRESUMO
We report here a case of primitive plasma cell leukemia with immunoglobulin (Ig) E. IgE myeloma is an exceptional variant of multiple myeloma, with a very poor prognosis. Its biological diagnosis requires specific analyzes in order to detect IgE gammopathy. Plasma cell leukemia (PCL) is also a very rare and very severe form of multiple myeloma. There are two variants: primitive PCL (pPCL) occurring de novo and secondary PCL (sPCL), evolution of a preexisting myeloma. Its diagnosis is essentially biological since it is defined by a blood plasmocytosis greater than 2 G/L or 20% of the leucocytes.
Assuntos
Imunoglobulina E/sangue , Leucemia Plasmocitária/sangue , Leucemia Plasmocitária/diagnóstico , Idoso , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Humanos , Leucemia Plasmocitária/imunologia , Masculino , PrognósticoRESUMO
Chronic lymphocytic leukemia (CLL) is a common B-cell malignancy with a remarkably heterogeneous course, ranging from indolent disease with no need for immediate therapy to rapidly progressive disease associated with therapeutic resistance. The recent US Food and Drug Administration approvals of novel targeted therapies such as inhibitors of B-cell receptor signaling and B-cell lymphoma 2 have opened up new opportunities in the clinical management of patients with CLL and heralded a new era in the clinical treatment of this disease. In parallel, the implementation of novel sequencing technologies has provided new insights into CLL complexity, identifying a growing list of putative drivers that underlie inter- and intratumor heterogeneities in CLL affecting disease progression and resistance. The identification of these novel genomic features that can indicate future drug resistance or guide therapeutic management is now becoming a major goal in CLL so that patients can best benefit from the increasingly diverse available therapies, as discussed herein.