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1.
Blood ; 123(21): 3247-54, 2014 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-24652989

RESUMEN

Mutations in TP53, NOTCH1, and SF3B1 were analyzed in the CLL8 study evaluating first-line therapy with fludarabine and cyclophosphamide (FC) or FC with rituximab (FCR) among patients with untreated chronic lymphocytic leukemia (CLL). TP53, NOTCH1, and SF3B1 were mutated in 11.5%, 10.0%, and 18.4% of patients, respectively. NOTCH1(mut) and SF3B1(mut) virtually showed mutual exclusivity (0.6% concurrence), but TP53(mut) was frequently found in NOTCH1(mut) (16.1%) and in SF3B1(mut) (14.0%) patients. There were few significant associations with clinical and laboratory characteristics, but genetic markers had a strong influence on response and survival. In multivariable analyses, an independent prognostic impact was found for FCR, thymidine kinase (TK) ≥10 U/L, unmutated IGHV, 11q deletion, 17p deletion, TP53(mut), and SF3B1(mut) on progression-free survival; and for FCR, age ≥65 years, Eastern Cooperative Oncology Group performance status ≥1, ß2-microglobulin ≥3.5 mg/L, TK ≥10 U/L, unmutated IGHV, 17p deletion, and TP53(mut) on overall survival. Notably, predictive marker analysis identified an interaction of NOTCH1 mutational status and treatment in that rituximab failed to improve response and survival in patients with NOTCH1(mut). In conclusion, TP53 and SF3B1 mutations appear among the strongest prognostic markers in CLL patients receiving current-standard first-line therapy. NOTCH1(mut) was identified as a predictive marker for decreased benefit from the addition of rituximab to FC. This study is registered at www.clinicaltrials.gov as #NCT00281918.


Asunto(s)
Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Mutación , Fosfoproteínas/genética , Receptor Notch1/genética , Ribonucleoproteína Nuclear Pequeña U2/genética , Proteína p53 Supresora de Tumor/genética , Anciano , Anticuerpos Monoclonales de Origen Murino/uso terapéutico , Antimetabolitos/uso terapéutico , Antineoplásicos Alquilantes/uso terapéutico , Ciclofosfamida/uso terapéutico , Femenino , Humanos , Leucemia Linfocítica Crónica de Células B/diagnóstico , Leucemia Linfocítica Crónica de Células B/genética , Masculino , Persona de Mediana Edad , Pronóstico , Factores de Empalme de ARN , Rituximab , Análisis de Supervivencia , Resultado del Tratamiento , Vidarabina/uso terapéutico
2.
Blood ; 121(23): 4708-17, 2013 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-23580660

RESUMEN

Antigenic targets of the B-cell receptor (BCR) derived from malignant cells in chronic lymphocytic leukemia (CLL) might play a role in the pathogenesis of this neoplasm. We screened human tissue-derived protein macroarrays with antigen-binding fragments derived from 47 consecutive cases of CLL. An autoantigenic target was identified for 12/47 (25.5%) of the cases, with 3 autoantigens being the target of the BCRs from 2 patients each. Recombinantly expressed autoantigens bound specifically to the CLL cells from which the BCR used for the identification of the respective autoantigen was derived. Moreover, binding of the autoantigen to the respective leukemic cells induced a specific activation and proliferation of these cells. In conclusion, autoantigens are frequent targets of CLL-BCRs. Their specific binding to and induction of proliferation in the respective leukemic cells provide the most convincing evidence to date for the long-time hypothesized role of autoantigens in the pathogenesis of CLL.


Asunto(s)
Autoantígenos/metabolismo , Linfocitos B/metabolismo , Proliferación Celular , Leucemia Linfocítica Crónica de Células B/patología , Receptores de Antígenos de Linfocitos B/metabolismo , Autoantígenos/inmunología , Linfocitos B/inmunología , Linfocitos B/patología , Western Blotting , Células Cultivadas , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Humanos , Antígeno Ki-67/metabolismo , Leucemia Linfocítica Crónica de Células B/inmunología , Leucemia Linfocítica Crónica de Células B/metabolismo , Proteínas Proto-Oncogénicas c-myc/metabolismo
3.
Blood ; 122(7): 1266-70, 2013 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-23821658

RESUMEN

We studied the incidences, associations, and prognostic roles of NOTCH1 and SF3B1 mutations (NOTCH1(mut), SF3B1(mut)) as compared with TP53(mut) in fludarabine-refractory chronic lymphocytic leukemia (CLL) patients treated with alemtuzumab in the CLL2H trial. We found NOTCH1(mut), SF3B1(mut), and TP53(mut) in 13.4%, 17.5%, and 37.4% of patients, respectively. NOTCH1(mut) and SF3B1(mut) were mutually exclusive, whereas TP53(mut) were evenly distributed within both subgroups. Apart from correlation of SF3B1(mut) with 11q deletion (P = .029), there were no other significant associations of the mutations with any baseline characteristics or response rates. However, NOTCH1(mut) cases had a significantly longer progression-free survival (PFS) compared with wild-type cases (15.47 vs 6.74 months; P = .025), although there was no significant difference with overall survival (OS). SF3B1(mut) had no significant impact on PFS and OS. In multivariable analyses, NOTCH1(mut) was identified as an independent favorable marker for PFS. This clinical trial is registered at www.clinicaltrials.gov as #NCT00274976.


Asunto(s)
Anticuerpos Monoclonales Humanizados/uso terapéutico , Antineoplásicos/uso terapéutico , Resistencia a Antineoplásicos/genética , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Fosfoproteínas/genética , Receptor Notch1/genética , Ribonucleoproteína Nuclear Pequeña U2/genética , Proteína p53 Supresora de Tumor/genética , Vidarabina/análogos & derivados , Alemtuzumab , Estudios de Seguimiento , Humanos , Leucemia Linfocítica Crónica de Células B/genética , Leucemia Linfocítica Crónica de Células B/mortalidad , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/mortalidad , Pronóstico , Estudios Prospectivos , Factores de Empalme de ARN , Tasa de Supervivencia , Vidarabina/farmacología
4.
Blood ; 121(16): 3284-8, 2013 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-23435461

RESUMEN

The purpose of this analysis was to provide 6-year follow-up of the CLL3X trial, which studied reduced-intensity allogeneic hematopoietic stem cell transplantation (HSCT) in patients with poor-risk chronic lymphocytic leukemia (CLL), and to investigate the effect of TP53, SF3B1, and NOTCH1 mutations on HSCT outcome. For 90 allografted patients, 6-year overall survival (OS) was 58% and 6-year event-free survival (EFS) was 38%. TP53, SF3B1, and NOTCH1 mutations were found in 30%, 26%, and 14% of the trial population, respectively. By univariate and multivariate analyses, the mutational status of the TP53, SF3B1, and NOTCH1 genes had no significant effect on OS and EFS. Studies of minimal residual disease confirmed durability of CLL eradication in mutated patients. We conclude that HSCT can provide long-term disease control in patients with poor-risk CLL independent of the presence of TP53, SF3B1, and NOTCH1 mutations. The trial has been registered at the US National Cancer Institute as #EU-20554, NCT00281983.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Leucemia Linfocítica Crónica de Células B/genética , Leucemia Linfocítica Crónica de Células B/terapia , Mutación , Fosfoproteínas/genética , Receptor Notch1/genética , Ribonucleoproteína Nuclear Pequeña U2/genética , Proteína p53 Supresora de Tumor/genética , Adulto , Anciano , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Trasplante de Células Madre Hematopoyéticas/métodos , Humanos , Leucemia Linfocítica Crónica de Células B/cirugía , Masculino , Persona de Mediana Edad , Factores de Empalme de ARN , Trasplante Homólogo/métodos , Resultado del Tratamiento
5.
Blood ; 119(21): 4851-9, 2012 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-22490331

RESUMEN

The CLL3 trial was designed to study intensive treatment including autologous stem cell transplantation (autoSCT) as part of first-line therapy in patients with chronic lymphocytic leukemia (CLL). Here, we present the long-term outcome of the trial with particular focus on the impact of genomic risk factors, and we provide a retrospective comparison with patients from the fludarabine-cyclophosphamide-rituximab (FCR) arm of the German CLL Study Group (GCLLSG) CLL8 trial. After a median observation time of 8.7 years (0.3-12.3 years), median progression-free survival (PFS), time to retreatment, and overall survival (OS) of 169 evaluable patients, including 38 patients who did not proceed to autoSCT, was 5.7, 7.3, and 11.3 years, respectively. PFS and OS were significantly reduced in the presence of 17p- and of an unfavorable immunoglobulin heavy variable chain mutational status, but not of 11q-. Five-year nonrelapse mortality was 6.5%. When 110 CLL3 patients were compared with 126 matched patients from the FCR arm of the CLL8 trial, 4-year time to retreatment (75% vs 77%) and OS (86% vs 90%) was similar despite a significant benefit for autoSCT in terms of PFS. In summary, early treatment intensification including autoSCT can provide very effective disease control in poor-risk CLL, although its clinical benefit in the FCR era remains uncertain. The trial has been registered with www.clinicaltrials.gov as NCT00275015.


Asunto(s)
Leucemia Linfocítica Crónica de Células B/terapia , Trasplante de Células Madre , Adolescente , Adulto , Estudios de Factibilidad , Femenino , Estudios de Seguimiento , Alemania/epidemiología , Humanos , Leucemia Linfocítica Crónica de Células B/epidemiología , Leucemia Linfocítica Crónica de Células B/mortalidad , Masculino , Persona de Mediana Edad , Trasplante de Células Madre/efectos adversos , Trasplante de Células Madre/métodos , Análisis de Supervivencia , Factores de Tiempo , Trasplante Autólogo , Adulto Joven
6.
Blood ; 120(24): 4783-94, 2012 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-23047824

RESUMEN

To identify genomic alterations in chronic lymphocytic leukemia (CLL), we performed single-nucleotide polymorphism-array analysis using Affymetrix Version 6.0 on 353 samples from untreated patients entered in the CLL8 treatment trial. Based on paired-sample analysis (n = 144), a mean of 1.8 copy number alterations per patient were identified; approximately 60% of patients carried no copy number alterations other than those detected by fluorescence in situ hybridization analysis. Copy-neutral loss-of-heterozygosity was detected in 6% of CLL patients and was found most frequently on 13q, 17p, and 11q. Minimally deleted regions were refined on 13q14 (deleted in 61% of patients) to the DLEU1 and DLEU2 genes, on 11q22.3 (27% of patients) to ATM, on 2p16.1-2p15 (gained in 7% of patients) to a 1.9-Mb fragment containing 9 genes, and on 8q24.21 (5% of patients) to a segment 486 kb proximal to the MYC locus. 13q deletions exhibited proximal and distal breakpoint cluster regions. Among the most common novel lesions were deletions at 15q15.1 (4% of patients), with the smallest deletion (70.48 kb) found in the MGA locus. Sequence analysis of MGA in 59 samples revealed a truncating mutation in one CLL patient lacking a 15q deletion. MNT at 17p13.3, which in addition to MGA and MYC encodes for the network of MAX-interacting proteins, was also deleted recurrently.


Asunto(s)
Aberraciones Cromosómicas , Perfilación de la Expresión Génica/métodos , Genómica/métodos , Leucemia Linfocítica Crónica de Células B/genética , Variaciones en el Número de Copia de ADN , Femenino , Humanos , Cadenas Pesadas de Inmunoglobulina/genética , Región Variable de Inmunoglobulina/genética , Hibridación Fluorescente in Situ , Estimación de Kaplan-Meier , Pérdida de Heterocigocidad , Masculino , Mutación , Análisis de Secuencia por Matrices de Oligonucleótidos , Polimorfismo de Nucleótido Simple , Proteína p53 Supresora de Tumor/genética
7.
Blood ; 117(5): 1622-32, 2011 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-21115975

RESUMEN

The DNA damage pathway plays a central role in chemoresistance in chronic lymphocytic leukemia (CLL), as indicated by the prognostic impact of TP53 and ATM loss/mutations. We investigated the function of the p53 axis in primary CLL samples by studying p53 and p21 responses to irradiation by FACS and RT-PCR. We observed a distinct response pattern for most cases with a 17p deletion (n = 16) or a sole TP53 mutation (n = 8), but not all cases with a p53 aberration were detected based on a number of different assays used. Samples with a small clone with a TP53 mutation remained undetected in all assays. Only 1 of 123 cases showed high expression of p53, which is suggestive of p53 aberration without proof of mutation of TP53. Samples with an 11q deletion showed a heterogeneous response, with only 13 of 30 showing an abnormal response based on cutoff. Nevertheless, the overall induction of p53 and p21 was impaired, suggesting a gene-dosage effect for ATM in the 11q-deleted samples. The detectability of p53 defects is influenced by clonal heterogeneity and sample purity. Functional assays of p53 defects will detect a small number of cases not detectable by FISH or TP53 mutational analysis. The clinical utility of functional p53 testing will need to be derived from clinical trials.


Asunto(s)
Cromosomas Humanos Par 17/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Daño del ADN , Leucemia Linfocítica Crónica de Células B/genética , Leucemia Linfocítica Crónica de Células B/patología , Proteína p53 Supresora de Tumor/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Western Blotting , Adhesión Celular , Ciclo Celular , Diferenciación Celular , Movimiento Celular , Proliferación Celular , Células Cultivadas , Deleción Cromosómica , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Análisis Mutacional de ADN , Femenino , Citometría de Flujo , Humanos , Hibridación Fluorescente in Situ , Linfocitos/metabolismo , Linfocitos/patología , Masculino , Persona de Mediana Edad , Mutación/genética , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transcripción Genética
8.
Int J Cancer ; 128(7): 1747-50, 2011 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-20533286

RESUMEN

Chronic lymphocytic leukemia (CLL) cells show constitutive nuclear factor kappa B (NF-κB) activation, which may have a pathogenetic role. The mechanisms causing this NF-κB activity are poorly understood. A20, encoded by the TNFAIP3 gene, is a repressor of the NF-κB pathway and was recently shown to be frequently inactivated by deletions and/or point mutations in several types of B-cell lymphomas. Here, we studied 48 CLL, including at least 12 cases with a deletion of one allele of TNFAIP3, for mutations. However, only one case harboured a silent mutation, all other cases were unmutated. Therefore, A20 inactivation plays no significant role in the pathogenesis of CLL, and the recurrent deletion in CLL on 6q21-23, where TNFAIP3 is located, likely affects other gene(s).


Asunto(s)
Cromosomas Humanos Par 6 , Análisis Mutacional de ADN/métodos , Péptidos y Proteínas de Señalización Intracelular/genética , Leucemia Linfocítica Crónica de Células B/genética , Proteínas Nucleares/genética , Anciano , Proteínas de Unión al ADN , Exones , Eliminación de Gen , Genes Supresores de Tumor , Humanos , Persona de Mediana Edad , Mutación , FN-kappa B/metabolismo , Reacción en Cadena de la Polimerasa , Proteína 3 Inducida por el Factor de Necrosis Tumoral alfa
9.
Blood ; 113(16): 3801-8, 2009 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-18941118

RESUMEN

17p (TP53) deletion identifies patients with chronic lymphocytic leukemia (CLL) who are resistant to chemotherapy. The members of the miR-34 family have been discovered to be direct p53 targets and mediate some of the p53-dependent effects. We studied miR-34a and miR-34b/c expression in a large cohort to define their potential role in refractory CLL. While no expression of miR-34b/c could be detected, we found variable expression levels of miR-34a. miR-34a levels were up-regulated after DNA damage in the presence of functional p53, but not in cases with 17p deletion (P < .001). We found a strong correlation of low miR-34a levels with impaired DNA damage response, TP53 mutations (without 17p deletion), and fludarabine-refractory disease (also in the absence of 17p deletion). Up-regulation of miR-34a after irradiation was associated with induction of Bax and p21, but not Puma. CLL cells with reduced miR-34a expression showed increased viability after DNA damage independently of 17p status. Therefore, low expression of miR-34a in CLL is associated with p53 inactivation but also chemotherapy-refractory disease, impaired DNA damage response, and apoptosis resistance irrespective of 17p deletion/TP53 mutation. The elucidation of mechanisms underlying miR-34a regulation and overcoming its role in chemotherapy resistance warrant further study.


Asunto(s)
Regulación Leucémica de la Expresión Génica , Leucemia Linfocítica Crónica de Células B/metabolismo , MicroARNs/biosíntesis , ARN Neoplásico/biosíntesis , Adulto , Anciano , Anciano de 80 o más Años , Apoptosis/efectos de la radiación , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Deleción Cromosómica , Cromosomas Humanos Par 17/genética , Cromosomas Humanos Par 17/metabolismo , Estudios de Cohortes , Daño del ADN/efectos de la radiación , Femenino , Humanos , Leucemia Linfocítica Crónica de Células B/genética , Masculino , MicroARNs/genética , Persona de Mediana Edad , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , ARN Neoplásico/genética , Células Tumorales Cultivadas , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Regulación hacia Arriba/efectos de la radiación , Proteína X Asociada a bcl-2/genética , Proteína X Asociada a bcl-2/metabolismo
10.
Blood ; 114(13): 2589-97, 2009 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-19643983

RESUMEN

The prognosis of fludarabine (F)-refractory chronic lymphocytic leukemia (CLL) is very poor, and underlying mechanisms are only partly understood. To assess the contribution of p53 abnormalities to F-refractory CLL, we studied TP53 mutations in the CLL2H trial (subcutaneous alemtuzumab; n = 99). We found TP53 mutations in 37% of patients. Twelve of 67 (18%) patients without the 17p deletion showed a TP53 mutation and 50% showed evidence of uniparental disomy. A total of 75% of cases with TP53 mutation (without 17p-) showed clonal evolution/expansion. TP53 mutations had no impact on overall survival (P = .48). CLL with the 17p deletion or TP53 mutation showed very low miR-34a expression. To investigate the mechanisms underlying refractory CLL beyond p53, we studied cases without 17p-/TP53 mutation in detail. In several paired samples before and after F-refractory disease, no change in p21/p53 induction was observed after DNA damage. Although TP53 mutations and 17p deletions are found in a high proportion of F-refractory CLL, more than half of the cases cannot be explained by p53 defects (deletion or mutation), and alternative mechanisms need to be investigated. Alemtuzumab is effective irrespective of genetic high-risk subgroups with TP53 mutations. These clinical trials are registered at www.clinicaltrials.gov as #NCT00274976.


Asunto(s)
Deleción Cromosómica , Cromosomas Humanos Par 17 , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/genética , MicroARNs/genética , Proteína p53 Supresora de Tumor/genética , Vidarabina/análogos & derivados , Administración Cutánea , Alemtuzumab , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales Humanizados , Anticuerpos Antineoplásicos/administración & dosificación , Antineoplásicos/uso terapéutico , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Análisis Mutacional de ADN , Resistencia a Antineoplásicos/genética , Estudios de Seguimiento , Regulación Leucémica de la Expresión Génica , Predisposición Genética a la Enfermedad , Humanos , MicroARNs/fisiología , Transducción de Señal/genética , Insuficiencia del Tratamiento , Proteína p53 Supresora de Tumor/fisiología , Vidarabina/uso terapéutico
11.
Blood ; 112(8): 3322-9, 2008 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-18689542

RESUMEN

The exact prognostic role of TP53 mutations (without 17p deletion) and any impact of the deletion without TP53 mutation in CLL are unclear. We studied 126 well-characterized CLL patients by direct sequencing and DHPLC to detect TP53 mutations (exons 2-11). Most patients with 17p deletions also had TP53 mutations (81%). Mutations in the absence of 17p deletions were found in 4.5%. We found a shorter survival for patients with TP53 mutation (n = 18; P = .002), which was more pronounced when analyzed from the time point of mutation detection (6.8 vs 69 months, P < .001). The survival was equally poor for patients with deletion 17p plus TP53 mutation (7.6 months, n = 13), TP53 mutation only (5.5 months, n = 5), and 17p deletion only (5.4 months, n = 3). The prognostic impact of TP53 mutation (HR 3.71) was shown to be independent of stage, VH status, and 11q and 17p deletion in multivariate analysis. Serial samples showed evidence of clonal evolution and increasing clone size during chemotherapy, suggesting that there may be patients where this treatment is potentially harmful. TP53 mutations are associated with poor sur-vival once they occur in CLL. The de-monstration of clonal evolution under selective pressure supports the biologic significance of TP53 mutations in CLL.


Asunto(s)
Genes p53 , Leucemia Linfocítica Crónica de Células B/diagnóstico , Leucemia Linfocítica Crónica de Células B/genética , Mutación , Adulto , Anciano , Anciano de 80 o más Años , Cromosomas Humanos Par 17 , Estudios de Cohortes , Estudios de Seguimiento , Eliminación de Gen , Humanos , Leucemia Linfocítica Crónica de Células B/mortalidad , Persona de Mediana Edad , Pronóstico , Factores de Tiempo , Resultado del Tratamiento
12.
Haematologica ; 95(11): 1880-8, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20713460

RESUMEN

BACKGROUND: Chronic lymphocytic leukemia has a variable clinical course. Genomic aberrations identify prognostic subgroups, pointing towards distinct underlying biological mechanisms that are poorly understood. In particular it remains unclear whether the prognostic subgroups of chronic lymphocytic leukemia are characterized by different levels of leukemogenic proteins. DESIGN AND METHODS: Expression of 23 proteins involved in apoptosis, proliferation, DNA damage, and signaling or whose genes map to chromosomal regions known to be critical in chronic lymphocytic leukemia was quantified in 185 cytogenetically well characterized cases of chronic lymphocytic leukemia using immunoblotting. Cases were categorized hierarchically into deletion(17p), deletion(11q), trisomy 12, deletion(13q) as sole abnormality or normal karyotype. Statistical analysis was performed for expression differences between these subgroups. In addition, the expression levels of CDK4, P27 and P53 were quantified over the clinical course and compared to levels in immunopurified B cells from healthy individuals. RESULTS: In subgroups with a good prognosis, differential expression was mainly seen for proteins that regulate apoptosis. In contrast, in cytogenetic subgroups with a worse prognosis, differential expression was mostly detected for proteins that control DNA damage and proliferation. Expression levels of CDK4, P27 and P53 were higher compared to those in B cells from healthy individuals and significantly correlated with increasing hierarchical risk. In addition, no significant longitudinal changes of expression levels of CDK4, P27 and P53 could be detected in chronic lymphocytic leukemia patients. CONCLUSIONS: Differences in expression levels of apoptosis- and proliferation-controlling proteins define distinct prognostic subgroups of chronic lymphocytic leukemia and uncover a correlation of levels of CDK4, P27 and P53 proteins with higher hierarchical risk.


Asunto(s)
Aberraciones Cromosómicas , Quinasa 4 Dependiente de la Ciclina/biosíntesis , Regulación Leucémica de la Expresión Génica , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Leucemia Linfocítica Crónica de Células B/metabolismo , Proteína p53 Supresora de Tumor/biosíntesis , Apoptosis/genética , Linfocitos B/metabolismo , Línea Celular Transformada , Línea Celular Tumoral , Proliferación Celular , Quinasa 4 Dependiente de la Ciclina/genética , Inhibidor p27 de las Quinasas Dependientes de la Ciclina , Femenino , Humanos , Péptidos y Proteínas de Señalización Intracelular/genética , Leucemia Linfocítica Crónica de Células B/diagnóstico , Leucemia Linfocítica Crónica de Células B/genética , Leucemia Linfocítica Crónica de Células B/mortalidad , Masculino , Factores de Riesgo , Proteína p53 Supresora de Tumor/genética
13.
Haematologica ; 95(1): 102-9, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19951976

RESUMEN

BACKGROUND: A variety of surrogate markers for genetic features and outcome have been described in chronic lymphocytic leukemia based on gene expression analyses. Previous studies mostly focused on individual markers and selected disease characteristics, which makes it difficult to estimate the relative value of the novel markers. Therefore, in the present study a comprehensive approach was chosen investigating 18 promising, partly novel expression markers in a well characterized cohort of patients with long clinical follow-up and full genetic information (IGHV status, genomic abnormalities). DESIGN AND METHODS: Expression markers were evaluated using real-time quantitative reverse transcriptase polymerase chain reaction in CD19(+)-purified samples from 151 patients. Multivariate analyses were performed to test the markers' ability to identify patients at genetic risk and as prognostic markers in the context of established prognostic factors. RESULTS: For individual markers, ZAP70 expression provided the highest rate (81%) of correct assignment of patients at genetic risk (IGHV unmutated, V3-21 usage, 11q- or 17p-), followed by LPL and TCF7 (76% both). The assignment rate was improved to 88% by information from a four-gene combination (ZAP70, TCF7, DMD, ATM). In multivariate analysis of treatment-free survival, IGHV mutation status and expression of ADAM29 were of independent prognostic value besides disease stage. With regards to overall survival, expression of ATM, ADAM29, TCL1, and SEPT10 provided prognostic information in addition to that derived from clinical and genetic factors. CONCLUSIONS: Gene expression markers are suitable for screening but not as surrogates for the information from genetic risk factors. While many individual markers may be associated with outcome, only a few are of independent prognostic significance. With regard to prognosis estimation, the genetic prognostic factors cannot be replaced by the expression markers.


Asunto(s)
Regulación Neoplásica de la Expresión Génica/genética , Predisposición Genética a la Enfermedad/genética , Leucemia Linfocítica Crónica de Células B/genética , Leucemia Linfocítica Crónica de Células B/mortalidad , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/genética , Estudios de Cohortes , Femenino , Marcadores Genéticos/genética , Humanos , Leucemia Linfocítica Crónica de Células B/diagnóstico , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Tasa de Supervivencia/tendencias
14.
Leukemia ; 34(4): 1038-1051, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32042081

RESUMEN

The heterogeneity of early stage CLL challenges prognostication, and refinement of prognostic indices for risk-adapted management in this population is essential. The aim of the multicenter, prospective CLL1 trial was to explore a novel prognostic model (CLL1-PM) developed to identify risk groups, separating patients with favorable from others with dismal prognosis. A cohort of 539 clinically, biochemically, and genetically characterized Binet stage A patients were observed until progression, first-line treatment, or death. Multivariate analysis identified six independent factors associated with overall survival (OS) and time-to-first treatment (TTFT): del(17p), unmutated IGHV, del(11q), ß2-microglobulin >3.5 mg/dL, lymphocyte doubling time (LDT) <12 months, and age >60 years. These factors were integrated into the CLL1-PM, which stratified patients into four risk groups. The CLL1-PM was prognostic for OS and TTFT, e.g., the risk of treatment at 5 years was 85.9, 51.8, 27.6, and 11.3% for very low (0-1.5), low (2-4), high (4.5-6.5), and very high-risk (7-14) scores, respectively (P < 0.001). Notably, in addition to factors comprising CLL-IPI, we substantiated del(11q) and LDT as prognostic factors in early CLL. Altogether, our findings would be useful to effectively stratify Binet stage A patients, particularly within the scope of clinical trials evaluating novel agents.


Asunto(s)
Biomarcadores de Tumor/genética , Leucemia Linfocítica Crónica de Células B/genética , Leucemia Linfocítica Crónica de Células B/patología , Mutación , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Factores de Riesgo , Tasa de Supervivencia , Tiempo de Tratamiento
15.
Bio Protoc ; 8(18): e3010, 2018 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-34395800

RESUMEN

This protocol provides a detailed description of how to fabricate and use the dual-flow-RootChip (dfRootChip), a novel microfluidic platform for investigating root nutrition, root-microbe interactions and signaling and development in controlled asymmetric conditions. The dfRootChip was developed primarily to investigate how plants roots interact with their environment by simulating environmental heterogeneity. The goal of this protocol is to provide a detailed resource for researchers in the biological sciences wishing to employ the dfRootChip in particular, or microfluidic devices in general, in their laboratory.

16.
Leuk Lymphoma ; 57(6): 1291-9, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26763349

RESUMEN

The objective of this study was to evaluate the safety and efficacy of different lenalidomide starting doses in patients with relapsed/refractory chronic lymphocytic leukemia (CLL). CLL patients were randomized to receive lenalidomide at initial doses of 5, 10, or 15 mg/d (N = 103). Doses were escalated by 5 mg every 28-d up to a maximum of 25 mg/d; dose reductions in up to 5 mg decrements were permitted. The most common grade ≥3 adverse events (AEs) were neutropenia and thrombocytopenia. Ten patients died during therapy (four deaths considered as related to lenalidomide); 12 patients experienced second primary malignancies. The most common cause for treatment discontinuation was AEs. Overall response rates were similar across arms. Progression-free survival and overall survival rates were longer in patients who escalated treatment (to 15 or 20 mg/d) versus those who did not. Lower starting doses allowed subsequent dose escalation of lenalidomide while maintaining an acceptable tolerability profile in patients with relapsed/refractory CLL.


Asunto(s)
Antineoplásicos/administración & dosificación , Factores Inmunológicos/administración & dosificación , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/patología , Talidomida/análogos & derivados , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos/efectos adversos , Resistencia a Antineoplásicos , Femenino , Humanos , Factores Inmunológicos/efectos adversos , Estimación de Kaplan-Meier , Lenalidomida , Leucemia Linfocítica Crónica de Células B/mortalidad , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Recurrencia , Retratamiento , Talidomida/administración & dosificación , Talidomida/efectos adversos , Resultado del Tratamiento
17.
Leuk Res ; 39(5): 495-500, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25804339

RESUMEN

Early phase studies of alvocidib showed activity in relapsed CLL including patients with high risk genomic features and those refractory to fludarabine. A multi-center, international, phase II study of alvocidib in fludarabine refractory CLL was undertaken to validate these early results. Patients with fludarabine refractory CLL or prolymphocytic leukemia arising from CLL were treated with single agent alvocidib. The primary outcome measure was overall response rate, with secondary outcomes including survival, toxicity, and response duration. One hundred and sixty five patients were enrolled and 159 patients were treated. The median age was 61 years, the median number of prior therapies was 4, and 96% of patients were fludarabine refractory. The investigator-assessed overall response rate was 25%; the majority of responses were partial. Response rates were lower among patients with del(17p) (14%), but equivalent in patients with del(11q) or bulky lymphadenopathy. Median progression free and overall survival were 7.6 and 14.6 months, respectively. Tumor lysis occurred in 39 patients (25%), and 13 received hemodialysis. Diarrhea, fatigue, and hematologic toxicities were common. Alvocidib has clinical activity in patients with advanced, fludarabine refractory CLL. Future studies should focus on discovery of biomarkers of clinical response and tumor lysis, and enhanced supportive care measures.


Asunto(s)
Antineoplásicos/uso terapéutico , Flavonoides/uso terapéutico , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Piperidinas/uso terapéutico , Vidarabina/análogos & derivados , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Leucemia Linfocítica Crónica de Células B/mortalidad , Leucemia Linfocítica Crónica de Células B/patología , Masculino , Persona de Mediana Edad , Recurrencia , Análisis de Supervivencia , Insuficiencia del Tratamiento , Vidarabina/uso terapéutico
18.
Leuk Lymphoma ; 54(6): 1177-82, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23088640

RESUMEN

BRAF mutations have been shown to occur at a high frequency in melanoma and thyroid cancer, but also at lower frequencies in hematological malignancies. To assess the potential role of BRAF, we have sequenced exons 11 and 15 of BRAF in 138 cases with chronic lymphocytic leukemia (CLL) and 32 cases of B-cell prolymphocytic leukemia (B-PLL). We found an incidence of BRAF mutations of 2.8% in CLL (4/138), while no cases with B-PLL showed BRAF mutations. The analysis of a cohort of patients with fludarabine-refractory disease (n = 87) showed no increase in the mutation incidence, suggesting that this mutation is not selected for during the disease progression. A limited analysis of the effect of BRAF inhibition in primary CLL cells showed no cell death induction in CLL samples with and without BRAF mutations. Our analysis suggests that BRAF mutations occur at a low frequency in CLL. The pharmacological inhibition of MEK/ERK signaling using the mutant BRAF inhibitor PLX4720 showed no effect on viability in vitro in CLL cases.


Asunto(s)
Leucemia Linfocítica Crónica de Células B/genética , Mutación , Proteínas Proto-Oncogénicas B-raf/genética , Antineoplásicos/uso terapéutico , Apoptosis/genética , Exones , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Humanos , Indoles/uso terapéutico , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/metabolismo , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Niacinamida/análogos & derivados , Niacinamida/uso terapéutico , Compuestos de Fenilurea/uso terapéutico , Fosforilación , Inhibidores de Proteínas Quinasas/uso terapéutico , Transducción de Señal , Sorafenib , Sulfonamidas/uso terapéutico , Resultado del Tratamiento
19.
J Clin Oncol ; 30(9): 980-8, 2012 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-22331940

RESUMEN

PURPOSE: To determine the clinical significance of flow cytometric minimal residual disease (MRD) quantification in chronic lymphocytic leukemia (CLL) in addition to pretherapeutic risk factors and to compare the prognostic impact of MRD between the arms of the German CLL Study Group CLL8 trial. PATIENTS AND METHODS: MRD levels were prospectively quantified in 1,775 blood and bone marrow samples from 493 patients randomly assigned to receive fludarabine and cyclophosphamide (FC) or FC plus rituximab (FCR). Patients were categorized by MRD into low- (< 10(-4)), intermediate- (≥ 10(-4) to <10(-2)), and high-level (≥ 10(-2)) groups. RESULTS: Low MRD levels during and after therapy were associated with longer progression-free survival (PFS) and overall survival (OS; P < .0001). Median PFS is estimated at 68.7, 40.5, and 15.4 months for low, intermediate, and high MRD levels, respectively, when assessed 2 months after therapy. Compared with patients with low MRD, greater risks of disease progression were associated with intermediate and high MRD levels (hazard ratios, 2.49 and 14.7, respectively; both P < .0001). Median OS was 48.4 months in patients with high MRD and was not reached for lower MRD levels. MRD remained predictive for OS and PFS in multivariate analyses that included the most important pretherapeutic risk markers in CLL. PFS and OS did not differ between treatment arms within each MRD category. However, FCR induced low MRD levels more frequently than FC. CONCLUSION: MRD levels independently predict OS and PFS in CLL. Therefore, MRD quantification might serve as a surrogate marker to assess treatment efficacy in randomized trials before clinical end points can be evaluated.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/mortalidad , Neoplasia Residual/tratamiento farmacológico , Neoplasia Residual/mortalidad , Anticuerpos Monoclonales de Origen Murino/administración & dosificación , Ciclofosfamida/administración & dosificación , Progresión de la Enfermedad , Citometría de Flujo , Humanos , Neoplasia Residual/diagnóstico , Pronóstico , Estudios Prospectivos , Rituximab , Tasa de Supervivencia , Vidarabina/administración & dosificación , Vidarabina/análogos & derivados
20.
J Clin Oncol ; 30(26): 3209-16, 2012 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-22869884

RESUMEN

PURPOSE: We investigated the safety and efficacy of bendamustine and rituximab (BR) in previously untreated patients with chronic lymphocytic leukemia (CLL). PATIENTS AND METHODS: In all, 117 patients, age 34 to 78 years, 46.2% of patients at Binet stage C, and 25.6% of patients age 70 years or older received BR chemoimmunotherapy for first-line treatment of CLL. Bendamustine was administered at a dose of 90 mg/m(2) on days 1 and 2 combined with 375 mg/m(2) rituximab on day 0 of the first course and 500 mg/m(2) on day 1 during subsequent courses for up to six courses. RESULTS: Overall response rate was 88.0% (95% CI, 80.7% to 100.0%) with a complete response rate of 23.1% and a partial response rate of 64.9%. Ninety percent of patients with del(11q), 94.7% with trisomy 12, 37.5% with del(17p), and 89.4% with unmutated IGHV status responded to treatment. After a median observation time of 27.0 months, median event-free survival was 33.9 months, and 90.5% of patients were alive. Grade 3 or 4 severe infections occurred in 7.7% of patients. Grade 3 or 4 adverse events for neutropenia, thrombocytopenia, and anemia were documented in 19.7%, 22.2%, and 19.7% of patients, respectively. CONCLUSION: Chemoimmunotherapy with BR is effective and safe in patients with previously untreated CLL.


Asunto(s)
Anticuerpos Monoclonales de Origen Murino/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Compuestos de Mostaza Nitrogenada/administración & dosificación , Adulto , Anciano , Anticuerpos Monoclonales de Origen Murino/análisis , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Clorhidrato de Bendamustina , Supervivencia sin Enfermedad , Esquema de Medicación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Compuestos de Mostaza Nitrogenada/efectos adversos , Rituximab
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