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1.
Proc Natl Acad Sci U S A ; 112(7): 2169-74, 2015 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-25646413

RESUMEN

B-cell chronic lymphocytic leukemia (CLL) is the most common human leukemia and dysregulation of the T-cell leukemia/lymphoma 1 (TCL1) oncogene is a contributing event in the pathogenesis of the aggressive form of this disease based on transgenic mouse studies. To determine a role of microRNAs on the pathogenesis of the aggressive form of CLL we studied regulation of TCL1 expression in CLL by microRNAs. We identified miR-3676 as a regulator of TCL1 expression. We demonstrated that miR-3676 targets three consecutive 28-bp repeats within 3'UTR of TCL1 and showed that miR-3676 is a powerful inhibitor of TCL1. We further showed that miR-3676 expression is significantly down-regulated in four groups of CLL carrying the 11q deletions, 13q deletions, 17p deletions, or a normal karyotype compared with normal CD19(+) cord blood and peripheral blood B cells. In addition, the sequencing of 539 CLL samples revealed five germ-line mutations in six samples (1%) in miR-3676. Two of these mutations were loss-of-function mutations. Because miR-3676 is located at 17p13, only 500-kb centromeric of tumor protein p53 (Tp53), and is codeleted with Tp53, we propose that loss of miR-3676 causes high levels of TCL1 expression contributing to CLL progression.


Asunto(s)
Eliminación de Gen , Leucemia Linfocítica Crónica de Células B/genética , MicroARNs/genética , Proteínas Proto-Oncogénicas/genética , Proteína p53 Supresora de Tumor/genética , Humanos
2.
N Engl J Med ; 370(24): 2286-94, 2014 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-24869598

RESUMEN

BACKGROUND: Ibrutinib is an irreversible inhibitor of Bruton's tyrosine kinase (BTK) and is effective in chronic lymphocytic leukemia (CLL). Resistance to irreversible kinase inhibitors and resistance associated with BTK inhibition have not been characterized. Although only a small proportion of patients have had a relapse during ibrutinib therapy, an understanding of resistance mechanisms is important. We evaluated patients with relapsed disease to identify mutations that may mediate ibrutinib resistance. METHODS: We performed whole-exome sequencing at baseline and the time of relapse on samples from six patients with acquired resistance to ibrutinib therapy. We then performed functional analysis of identified mutations. In addition, we performed Ion Torrent sequencing for identified resistance mutations on samples from nine patients with prolonged lymphocytosis. RESULTS: We identified a cysteine-to-serine mutation in BTK at the binding site of ibrutinib in five patients and identified three distinct mutations in PLCγ2 in two patients. Functional analysis showed that the C481S mutation of BTK results in a protein that is only reversibly inhibited by ibrutinib. The R665W and L845F mutations in PLCγ2 are both potentially gain-of-function mutations that lead to autonomous B-cell-receptor activity. These mutations were not found in any of the patients with prolonged lymphocytosis who were taking ibrutinib. CONCLUSIONS: Resistance to the irreversible BTK inhibitor ibrutinib often involves mutation of a cysteine residue where ibrutinib binding occurs. This finding, combined with two additional mutations in PLCγ2 that are immediately downstream of BTK, underscores the importance of the B-cell-receptor pathway in the mechanism of action of ibrutinib in CLL. (Funded by the National Cancer Institute and others.).


Asunto(s)
Resistencia a Antineoplásicos/genética , Leucemia Linfocítica Crónica de Células B/genética , Fosfolipasa C gamma/genética , Mutación Puntual , Proteínas Tirosina Quinasas/genética , Pirazoles/uso terapéutico , Pirimidinas/uso terapéutico , Adenina/análogos & derivados , Agammaglobulinemia Tirosina Quinasa , Anciano , Sitios de Unión/genética , Exoma , Humanos , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Persona de Mediana Edad , Fosfolipasa C gamma/metabolismo , Piperidinas , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Pirazoles/farmacología , Pirimidinas/farmacología , Receptores de Antígenos de Linfocitos B/metabolismo , Recurrencia , Análisis de Secuencia de ADN
4.
Blood ; 126(1): 61-8, 2015 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-25972157

RESUMEN

Ibrutinib has significantly improved the outcome of patients with relapsed chronic lymphocytic leukemia (CLL). Recent reports attribute ibrutinib resistance to acquired mutations in Bruton agammaglobulinemia tyrosine kinase (BTK), the target of ibrutinib, as well as the immediate downstream effector phospholipase C, γ2 (PLCG2). Although the C481S mutation found in BTK has been shown to disable ibrutinib's capacity to irreversibly bind this primary target, the detailed mechanisms of mutations in PLCG2 have yet to be established. Herein, we characterize the enhanced signaling competence, BTK independence, and surface immunoglobulin dependence of the PLCG2 mutation at R665W, which has been documented in ibrutinib-resistant CLL. Our data demonstrate that this missense alteration elicits BTK-independent activation after B-cell receptor engagement, implying the formation of a novel BTK-bypass pathway. Consistent with previous results, PLCG2(R665W) confers hypermorphic induction of downstream signaling events. Our studies reveal that proximal kinases SYK and LYN are critical for the activation of mutant PLCG2 and that therapeutics targeting SYK and LYN can combat molecular resistance in cell line models and primary CLL cells from ibrutinib-resistant patients. Altogether, our results engender a molecular understanding of the identified aberration at PLCG2 and explore its functional dependency on BTK, SYK, and LYN, suggesting alternative strategies to combat acquired ibrutinib resistance.


Asunto(s)
Resistencia a Antineoplásicos/genética , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/genética , Fosfolipasa C gamma/genética , Proteínas Tirosina Quinasas/fisiología , Pirazoles/uso terapéutico , Pirimidinas/uso terapéutico , Receptores de Antígenos de Linfocitos B/metabolismo , Adenina/análogos & derivados , Agammaglobulinemia Tirosina Quinasa , Animales , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Células Cultivadas , Pollos , Resistencia a Antineoplásicos/efectos de los fármacos , Humanos , Péptidos y Proteínas de Señalización Intracelular/antagonistas & inhibidores , Leucemia Linfocítica Crónica de Células B/metabolismo , Mutación Missense , Piperidinas , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Transducción de Señal/genética , Quinasa Syk , Familia-src Quinasas/antagonistas & inhibidores
5.
Blood ; 123(12): 1810-7, 2014 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-24415539

RESUMEN

The Bruton's tyrosine kinase (BTK) inhibitor ibrutinib has outstanding activity in patients with chronic lymphocytic leukemia. Most patients experience lymphocytosis, representing lymphocyte egress from nodal compartments. This resolves within 8 months in the majority of patients, but a subgroup has lymphocytosis lasting >12 months. Here we report a detailed characterization of patients with persistent lymphocytosis during ibrutinib therapy. Signaling evaluation showed that while BTK is inhibited, downstream mediators of B-cell receptor (BCR) signaling are activated in persistent lymphocytes. These cells cannot be stimulated through the BCR and do not show evidence of target gene activation. Flow cytometry for κ and λ expression, IGHV sequencing, Zap-70 methylation, and targeted gene sequencing in these patients are identical at baseline and later time points, suggesting that persistent lymphocytes do not represent clonal evolution. In vitro treatment with targeted kinase inhibitors shows that they are not addicted to a single survival pathway. Finally, progression-free survival is not inferior for patients with prolonged lymphocytosis vs those with traditional responses. Thus, prolonged lymphocytosis is common following ibrutinib treatment, likely represents the persistence of a quiescent clone, and does not predict a subgroup of patients likely to relapse early.


Asunto(s)
Linfocitosis/etiología , Pirazoles/efectos adversos , Pirimidinas/efectos adversos , Adenina/análogos & derivados , Adulto , Agammaglobulinemia Tirosina Quinasa , Anciano , Anciano de 80 o más Años , Ligando de CD40/metabolismo , Supervivencia sin Enfermedad , Femenino , Humanos , Leucemia Linfocítica Crónica de Células B/sangre , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/inmunología , Linfocitos/efectos de los fármacos , Linfocitos/inmunología , Linfocitos/metabolismo , Linfocitosis/sangre , Linfocitosis/inmunología , Masculino , Persona de Mediana Edad , Fosfolipasa C gamma/antagonistas & inhibidores , Fosforilación , Piperidinas , Pronóstico , Inhibidores de Proteínas Quinasas/efectos adversos , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Receptores de Antígenos de Linfocitos B/metabolismo , Transducción de Señal/efectos de los fármacos , Proteína Tirosina Quinasa ZAP-70/metabolismo
6.
Am J Hematol ; 91(4): 395-9, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26800311

RESUMEN

De novo CD5+ diffuse large B-cell lymphomas (DLBCL) are a distinct subgroup of DLBCL with poor prognosis. However the role of rituximab-containing therapy and salvage stem cell transplantation in this patients' population remain to be defined. We retrospectively reviewed clinical features and outcomes of 102 patients with de novo CD5+ DLBCL treated with rituximab-containing therapy at nine different institutions. By Hans' criteria, 64 patients had activated B-cell (ABC) subtype, 24 germinal center B-cell (GCB) subtype, and 14 were not evaluated. No patients had a myc translocation. Eighty-three patients were treated with rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone (R-CHOP), 7 with rituximab, etoposide, cyclophosphamide, doxorubicin, vincristine, prednisone (R-EPOCH), and 6 with R-CHOP with methotrexate, 3 g/m(2) . The overall response rate to front-line therapy was 85%. The 3-year progression free survival (PFS) and overall survival (OS) for all patients were 40 and 65%, respectively. The 3-year PFS for ABC- and GCB-subtypes was 34 and 45%, respectively. The 3-year OS for ABC- and GCB-subtypes was 62 and 67%, respectively. The median time to second treatment failure was 3 months and 1 month for ABC- and GCB-subtypes, respectively. Twenty of 28 (71%) transplanted patients with autologous, allogeneic, or both, relapsed. This study confirms the poor prognosis of de novo CD5+ DLBCL in a large multi-center cohort despite initial rituximab-containing chemotherapy and suggests that stem cell transplantation fails to salvage the majority of these patients. Approaches to prevent recurrence and/or novel therapies for relapsed disease are needed for this subgroup of DLBCL patients.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Antígenos CD5/metabolismo , Trasplante de Células Madre Hematopoyéticas , Linfoma de Células B Grandes Difuso/metabolismo , Linfoma de Células B Grandes Difuso/terapia , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Trasplante de Células Madre Hematopoyéticas/métodos , Humanos , Linfoma de Células B Grandes Difuso/diagnóstico , Linfoma de Células B Grandes Difuso/mortalidad , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Recurrencia , Rituximab/administración & dosificación , Análisis de Supervivencia , Resultado del Tratamiento , Adulto Joven
7.
Cell Rep ; 40(3): 111115, 2022 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-35858552

RESUMEN

The existence of "leukemia-initiating cells" (LICs) in chronic lymphocytic leukemia (CLL) remains controversial due to the difficulty in isolating and identifying the tumor-initiating cells. Here, we demonstrate a microchannel electroporation (MEP) microarray that injects RNA-detecting probes into single live cells, allowing the imaging and characterization of heterogeneous LICs by intracellular RNA expression. Using limited-cell FACS sequencing (LC-FACSeq), we can detect and monitor rare live LICs during leukemogenesis and characterize their differential drug sensitivity. Disease-associated mutation accumulation in developing B lymphoid but not myeloid lineage in CLL patient hematopoietic stem cells (CLL-HSCs), and development of independent clonal CLL-like cells in murine patient-derived xenograft models, suggests the existence of CLL LICs. Furthermore, we identify differential protein ubiquitination and unfolding response signatures in GATA2high CLL-HSCs that exhibit increased sensitivity to lenalidomide and resistance to fludarabine compared to GATA2lowCLL-HSCs. These results highlight the existence of therapeutically targetable disease precursors in CLL.


Asunto(s)
Leucemia Linfocítica Crónica de Células B , Animales , Células Cultivadas , Células Madre Hematopoyéticas/metabolismo , Humanos , Leucemia Linfocítica Crónica de Células B/genética , Leucemia Linfocítica Crónica de Células B/metabolismo , Ratones , Células Madre Neoplásicas/metabolismo , ARN/metabolismo
8.
Leukemia ; 35(12): 3406-3420, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34021247

RESUMEN

Hematopoiesis is hierarchical, and it has been postulated that acute myeloid leukemia (AML) is organized similarly with leukemia stem cells (LSCs) residing at the apex. Limited cells acquired by fluorescence activated cell sorting in tandem with targeted amplicon-based sequencing (LC-FACSeq) enables identification of mutations in small subpopulations of cells, such as LSCs. Leveraging this, we studied clonal compositions of immunophenotypically-defined compartments in AML through genomic and functional analyses at diagnosis, remission and relapse in 88 AML patients. Mutations involving DNA methylation pathways, transcription factors and spliceosomal machinery did not differ across compartments, while signaling pathway mutations were less frequent in putative LSCs. We also provide insights into TP53-mutated AML by demonstrating stepwise acquisition of mutations beginning from the preleukemic hematopoietic stem cell stage. In 10 analyzed cases, acquisition of additional mutations and del(17p) led to genetic and functional heterogeneity within the LSC pool with subclones harboring varying degrees of clonogenic potential. Finally, we use LC-FACSeq to track clonal evolution in serial samples, which can also be a powerful tool to direct targeted therapy against measurable residual disease. Therefore, studying clinically significant small subpopulations of cells can improve our understanding of AML biology and offers advantages over bulk sequencing to monitor the evolution of disease.


Asunto(s)
Biomarcadores de Tumor/genética , Evolución Clonal , Genómica/métodos , Células Madre Hematopoyéticas/patología , Leucemia Mieloide Aguda/patología , Mutación , Células Madre Neoplásicas/patología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Citometría de Flujo , Estudios de Seguimiento , Células Madre Hematopoyéticas/metabolismo , Humanos , Inmunofenotipificación , Leucemia Mieloide Aguda/genética , Masculino , Persona de Mediana Edad , Células Madre Neoplásicas/metabolismo , Pronóstico , Adulto Joven
9.
JCI Insight ; 5(12)2020 06 18.
Artículo en Inglés | MEDLINE | ID: mdl-32554930

RESUMEN

Detecting, characterizing, and monitoring rare populations of cells can increase testing sensitivity, give insight into disease mechanism, and inform clinical decision making. One area that can benefit from increased resolution is management of cancers in clinical remission but with measurable residual disease (MRD) by multicolor FACS. Detecting and monitoring genomic clonal resistance to treatment in the setting of MRD is technically difficult and resource intensive due to the limited amounts of disease cells. Here, we describe limited-cell FACS sequencing (LC-FACSeq), a reproducible, highly sensitive method of characterizing clonal evolution in rare cells relevant to different types of acute and chronic leukemias. We demonstrate the utility of LC-FACSeq for broad multigene gene panels and its application for monitoring sequential acquisition of mutations conferring therapy resistance and clonal evolution in long-term ibrutinib treatment of patients with chronic lymphocytic leukemia. This technique is generalizable for monitoring of other blood and marrow infiltrating cancers.


Asunto(s)
Adenina/análogos & derivados , Evolución Clonal/inmunología , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia/tratamiento farmacológico , Neoplasia Residual/tratamiento farmacológico , Piperidinas/uso terapéutico , Adenina/uso terapéutico , Células Clonales , Humanos , Leucemia/inmunología , Mutación/genética , Neoplasia Residual/diagnóstico
11.
J Clin Oncol ; 35(26): 3010-3020, 2017 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-28715249

RESUMEN

Purpose We evaluated the safety and feasibility of anti-CD19 chimeric antigen receptor-modified T (CAR-T) cell therapy in patients with chronic lymphocytic leukemia (CLL) who had previously received ibrutinib. Methods Twenty-four patients with CLL received lymphodepleting chemotherapy and anti-CD19 CAR-T cells at one of three dose levels (2 × 105, 2 × 106, or 2 × 107 CAR-T cells/kg). Nineteen patients experienced disease progression while receiving ibrutinib, three were ibrutinib intolerant, and two did not experience progression while receiving ibrutinib. Six patients were venetoclax refractory, and 23 had a complex karyotype and/or 17p deletion. Results Four weeks after CAR-T cell infusion, the overall response rate (complete response [CR] and/or partial response [PR]) by International Workshop on Chronic Lymphocytic Leukemia (IWCLL) criteria was 71% (17 of 24). Twenty patients (83%) developed cytokine release syndrome, and eight (33%) developed neurotoxicity, which was reversible in all but one patient with a fatal outcome. Twenty of 24 patients received cyclophosphamide and fludarabine lymphodepletion and CD19 CAR-T cells at or below the maximum tolerated dose (≤ 2 × 106 CAR-T cells/kg). In 19 of these patients who were restaged, the overall response rate by IWCLL imaging criteria 4 weeks after infusion was 74% (CR, 4/19, 21%; PR, 10/19, 53%), and 15/17 patients (88%) with marrow disease before CAR-T cells had no disease by flow cytometry after CAR-T cells. Twelve of these patients underwent deep IGH sequencing, and seven (58%) had no malignant IGH sequences detected in marrow. Absence of the malignant IGH clone in marrow of patients with CLL who responded by IWCLL criteria was associated with 100% progression-free survival and overall survival (median 6.6 months follow-up) after CAR-T cell immunotherapy. The progression-free survival was similar in patients with lymph node PR or CR by IWCLL criteria. Conclusion CD19 CAR-T cells are highly effective in high-risk patients with CLL after they experience treatment failure with ibrutinib therapy.


Asunto(s)
Inmunoterapia Adoptiva/métodos , Leucemia Linfocítica Crónica de Células B/terapia , Pirazoles/administración & dosificación , Pirimidinas/administración & dosificación , Receptores de Antígenos de Linfocitos T/inmunología , Linfocitos T/inmunología , Linfocitos T/trasplante , Adenina/análogos & derivados , Adulto , Anciano , Antígenos CD19/inmunología , Supervivencia sin Enfermedad , Humanos , Inmunoterapia Adoptiva/efectos adversos , Leucaféresis/métodos , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/inmunología , Depleción Linfocítica/métodos , Persona de Mediana Edad , Piperidinas , Pirazoles/efectos adversos , Pirimidinas/efectos adversos , Inducción de Remisión
12.
J Clin Oncol ; 35(13): 1437-1443, 2017 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-28418267

RESUMEN

Purpose Therapeutic targeting of Bruton tyrosine kinase (BTK) with ibrutinib in chronic lymphocytic leukemia has led to a paradigm shift in therapy, and relapse has been uncommon with current follow-up. Acquired mutations in BTK and PLCG2 can cause relapse, but data regarding the prevalence and natural history of these mutations are limited. Patients and Methods Patients accrued to four sequential studies of ibrutinib were included in these analyses. Deep sequencing for BTK and PLCG2 was performed retrospectively on patients who experienced relapse and prospectively on a screening population. Results With a median follow-up time of 3.4 years, the estimated cumulative incidence of progression at 4 years is 19% (95% CI, 14% to 24%). Baseline karyotypic complexity, presence of del(17)(p13.1), and age less than 65 years were risk factors for progression. Among patients who experienced relapse, acquired mutations of BTK or PLCG2 were found in 85% (95% CI, 71% to 94%), and these mutations were detected an estimated median of 9.3 months (95% CI, 7.6 to 11.7 months) before relapse. Of a group of 112 patients examined prospectively, eight patients have experienced relapse, and all of these patients had acquired resistance mutations before relapse. A resistance mutation was detected in an additional eight patients who have not yet met criteria for clinical relapse. Conclusion Relapse of chronic lymphocytic leukemia after ibrutinib is an issue of increasing clinical significance. We show that mutations in BTK and PLCG2 appear early and have the potential to be used as a biomarker for future relapse, suggesting an opportunity for intervention.


Asunto(s)
Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/enzimología , Proteínas Tirosina Quinasas/genética , Pirazoles/uso terapéutico , Pirimidinas/uso terapéutico , Adenina/análogos & derivados , Adulto , Agammaglobulinemia Tirosina Quinasa , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Resistencia a Antineoplásicos , Humanos , Leucemia Linfocítica Crónica de Células B/genética , Masculino , Persona de Mediana Edad , Fosfolipasa C gamma/genética , Piperidinas , Proteínas Tirosina Quinasas/metabolismo , Pirazoles/administración & dosificación , Pirazoles/farmacología , Pirimidinas/administración & dosificación , Pirimidinas/farmacología
14.
JAMA Oncol ; 1(1): 80-7, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26182309

RESUMEN

IMPORTANCE: The Bruton tyrosine kinase (BTK) inhibitor ibrutinib is effective in patients with chronic lymphocytic leukemia (CLL). Reasons for discontinuing therapy with this drug and outcomes following discontinuation have not been evaluated outside of clinical trials with relatively short follow-up. OBJECTIVE: To determine features associated with discontinuation of ibrutinib therapy and outcomes. DESIGN, SETTING, AND PARTICIPANTS: A total of 308 patients participating in 4 sequential trials of ibrutinib at The Ohio State University Comprehensive Cancer Center were included. These clinical trials accrued patients included in this analysis from May 2010 until April 2014, and data were locked in June 2014. MAIN OUTCOMES AND MEASURES: Patients were evaluated for time to therapy discontinuation, reasons for discontinuation, and survival following discontinuation. For patients who discontinued therapy because of disease progression, targeted deep sequencing was performed in samples at baseline and time of relapse. RESULTS: With a median follow-up of 20 months, 232 patients remained on therapy, 31 had discontinued because of disease progression, and 45 had discontinued for other reasons. Disease progression includes Richter's transformation (RT) or progressive CLL. Richter's transformation appeared to occur early and CLL progressions later (cumulative incidence at 12 months, 4.5% [95% CI, 2.0%-7.0%] and 0.3% [95% CI, 0%-1.0%], respectively). Median survival following RT was 3.5 months (95% CI, 0.3-6.0 months) and 17.6 months (95% CI, 4.7 months-"not reached") following CLL progression. Sequencing on peripheral blood from 8 patients with RT revealed 2 with mutations in BTK, and a lymph node sample showed no mutations in BTK or PLCG2. Deep sequencing on 11 patients with CLL progression revealed BTK or PLCG2 mutations in all. These mutations were not identified before treatment in any patient. CONCLUSIONS AND RELEVANCE: This single-institution experience with ibrutinib confirms it to be an effective therapy and identifies, for the first time, baseline factors associated with ibrutinib therapy discontinuation. Outcomes data show poor prognosis after discontinuation, especially for those patients with RT. Finally, sequencing data confirm initial reports associating mutations in BTK and PLCG2 with progression and clearly show that CLL progressions are associated with these mutations, while RT is likely not. TRIAL REGISTRATIONS: clinicaltrials.gov Identifiers:NCT01105247, NCT01217749, NCT01589302, and NCT01578707.


Asunto(s)
Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/uso terapéutico , Pirazoles/uso terapéutico , Pirimidinas/uso terapéutico , Adenina/análogos & derivados , Adulto , Agammaglobulinemia Tirosina Quinasa , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/antagonistas & inhibidores , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Ensayos Clínicos como Asunto , Análisis Mutacional de ADN/métodos , Progresión de la Enfermedad , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Estimación de Kaplan-Meier , Leucemia Linfocítica Crónica de Células B/diagnóstico , Leucemia Linfocítica Crónica de Células B/enzimología , Leucemia Linfocítica Crónica de Células B/genética , Leucemia Linfocítica Crónica de Células B/mortalidad , Masculino , Persona de Mediana Edad , Terapia Molecular Dirigida , Mutación , Ohio , Fosfolipasa C gamma/genética , Piperidinas , Inhibidores de Proteínas Quinasas/efectos adversos , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Proteínas Tirosina Quinasas/genética , Proteínas Tirosina Quinasas/metabolismo , Pirazoles/efectos adversos , Pirimidinas/efectos adversos , Recurrencia , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
15.
Leuk Lymphoma ; 56(11): 3031-7, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25721902

RESUMEN

Fludarabine (F) and cyclophosphamide (C) remain backbones of up-front chemotherapy regimens for chronic lymphocytic leukemia (CLL). We report long-term follow-up of a randomized F vs. FC trial in untreated CLL (#) . With median follow-up of 88 months, estimated median progression-free survival (PFS) was 19.3 vs. 48.1 months for F (n = 109) and FC (n = 118), respectively (p < 0.0001), and median overall survival (OS) was 88.0 vs. 79.1 months (p = 0.96). In multivariable analyses, variables associated with inferior PFS and OS respectively were age (p = 0.002, p < 0.001), Rai stage (p = 0.006, p = 0.02) and sex (p = 0.03, PFS only). Del(17)(p13.1) predicted shorter PFS and OS (p < 0.0001 for each), as did del(11q)(22.3) (p < 0.0001, p = 0.005, respectively), trisomy 12 with mutated Notch1 (p = 0.003, p = 0.03, respectively) and unmutated IGHV (p = 0.009, p = 0.002, respectively), all relative to patients without these features. These data confirm results from shorter follow-up and further justify targeted therapies for CLL.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Aberraciones Cromosómicas , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/genética , Vidarabina/análogos & derivados , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores , Islas de CpG , Ciclofosfamida/administración & dosificación , Metilación de ADN , Análisis Mutacional de ADN , Femenino , Estudios de Seguimiento , Humanos , Cadenas Pesadas de Inmunoglobulina/genética , Hibridación Fluorescente in Situ , Estimación de Kaplan-Meier , Leucemia Linfocítica Crónica de Células B/diagnóstico , Leucemia Linfocítica Crónica de Células B/mortalidad , Masculino , Persona de Mediana Edad , Análisis Multivariante , Mutación , Pronóstico , Resultado del Tratamiento , Vidarabina/administración & dosificación , Vidarabina/uso terapéutico , Proteína Tirosina Quinasa ZAP-70/genética
16.
PLoS One ; 8(10): e76607, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24130782

RESUMEN

Studies of chronic lymphocytic leukemia (CLL) have yielded substantial progress, however a lack of immortalized cell lines representative of the primary disease has hampered a full understanding of disease pathogenesis and development of new treatments. Here we describe a novel CLL cell line (OSU-CLL) generated by EBV transformation, which displays a similar cytogenetic and immunophenotype observed in the patient's CLL (CD5 positive with trisomy 12 and 19). A companion cell line was also generated from the same patient (OSU-NB). This cell line lacked typical CLL characteristics, and is likely derived from the patient's normal B cells. In vitro migration assays demonstrated that OSU-CLL exhibits migratory properties similar to primary CLL cells whereas OSU-NB has significantly reduced ability to migrate spontaneously or towards chemokine. Microarray analysis demonstrated distinct gene expression patterns in the two cell lines, including genes on chromosomes 12 and 19, which is consistent with the cytogenetic profile in this cell line. Finally, OSU-CLL was readily transplantable into NOG mice, producing uniform engraftment by three weeks with leukemic cells detectable in the peripheral blood spleen and bone marrow. These studies describe a new CLL cell line that extends currently available models to study gene function in this disease.


Asunto(s)
Línea Celular Tumoral , Leucemia Linfocítica Crónica de Células B/patología , Animales , Técnicas de Cultivo de Célula , Movimiento Celular , Transformación Celular Viral , Herpesvirus Humano 4/fisiología , Humanos , Leucemia Linfocítica Crónica de Células B/genética , Ratones , Fenotipo
17.
Leuk Lymphoma ; 53(9): 1743-8, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22369572

RESUMEN

The impact of mutation of the ATM (ataxia telangiectasia mutated) gene in chronic lymphocytic leukemia (CLL) treatment outcome has not been examined. We studied ATM mutations in 73 patients treated with fludarabine and rituximab. ATM gene mutation analysis was performed using temperature gradient capillary electrophoresis. The impact of detected variants on overall survival (OS) and progression-free survival (PFS) was tested with proportional hazards models. None of the 73 patients demonstrated truncating ATM mutations; 17 (23%, 95% confidence interval 14-35%) had non-silent variants (ATM-NSVs), including 13 known ATM polymorphisms and four missense variants. ATM-NSVs were not significantly associated with any baseline characteristics including immunoglobulin heavy chain variable gene (IGVH) status. In multivariable models, no significant differences in complete response (p =0.70), PFS (p =0.59) or OS (p =0.13) were observed. Our data indicate that truncating ATM mutations are rare in patients with CLL. Furthermore, in this dataset, these non-silent variants had limited impact on PFS and OS.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Proteínas de Ciclo Celular/genética , Proteínas de Unión al ADN/genética , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/genética , Mutación , Proteínas Serina-Treonina Quinasas/genética , Proteínas Supresoras de Tumor/genética , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales de Origen Murino/administración & dosificación , Proteínas de la Ataxia Telangiectasia Mutada , Análisis Mutacional de ADN , Supervivencia sin Enfermedad , Femenino , Humanos , Cadenas Pesadas de Inmunoglobulina/genética , Región Variable de Inmunoglobulina/genética , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Mutación Missense , Evaluación de Resultado en la Atención de Salud/estadística & datos numéricos , Polimorfismo de Nucleótido Simple , Modelos de Riesgos Proporcionales , Rituximab , Vidarabina/administración & dosificación , Vidarabina/análogos & derivados
18.
Cancer Cell ; 21(5): 694-708, 2012 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-22624718

RESUMEN

Tetraspanins are commonly believed to act only as "molecular facilitators," with no direct role in signal transduction. We herein demonstrate that upon ligation, CD37, a tetraspanin molecule expressed on mature normal and transformed B cells, becomes tyrosine phosphorylated, associates with proximal signaling molecules, and initiates a cascade of events leading to apoptosis. Moreover, we have identified two tyrosine residues with opposing regulatory functions: one lies in the N-terminal domain of CD37 in a predicted "ITIM-like" motif and mediates SHP1-dependent death, whereas the second lies in a predicted "ITAM motif" in the C-terminal domain of CD37 and counteracts death signals by mediating phosphatidylinositol 3-kinase-dependent survival.


Asunto(s)
Antígenos de Neoplasias/metabolismo , Apoptosis , Linfocitos B/metabolismo , Leucemia Linfocítica Crónica de Células B/metabolismo , Transducción de Señal , Tetraspaninas/metabolismo , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Antígenos de Neoplasias/química , Antígenos de Neoplasias/genética , Apoptosis/efectos de los fármacos , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Linfocitos B/efectos de los fármacos , Linfocitos B/patología , Proteína 11 Similar a Bcl2 , Línea Celular Tumoral , Supervivencia Celular , Cromatografía Liquida , Proteína Forkhead Box O3 , Factores de Transcripción Forkhead/metabolismo , Células HEK293 , Humanos , Inmunoglobulina G/farmacología , Leucemia Linfocítica Crónica de Células B/genética , Leucemia Linfocítica Crónica de Células B/patología , Microdominios de Membrana/metabolismo , Potencial de la Membrana Mitocondrial , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Datos de Secuencia Molecular , Nanotecnología , Fosfatidilinositol 3-Quinasa/metabolismo , Fosforilación , Transporte de Proteínas , Proteómica/métodos , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , Interferencia de ARN , Proteínas Recombinantes de Fusión/farmacología , Transducción de Señal/efectos de los fármacos , Espectrometría de Masas en Tándem , Tetraspaninas/química , Tetraspaninas/genética , Factores de Tiempo , Transfección , Tirosina
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