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1.
Br J Haematol ; 203(3): 416-425, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37580908

RESUMEN

Here we evaluated the epigenomic and transcriptomic profile of XPO1 mutant chronic lymphocytic leukaemia (CLL) and their clinical phenotype. By ATAC-seq, chromatin regions that were more accessible in XPO1 mutated CLL were enriched of binding sites for transcription factors regulated by pathways emanating from the B-cell receptor (BCR), including NF-κB signalling, p38-JNK and RAS-RAF-MEK-ERK. XPO1 mutant CLL, consistent with the chromatin accessibility changes, were enriched with transcriptomic features associated with BCR and cytokine signalling. By combining epigenomic and transcriptomic data, MIR155HG, the host gene of miR-155, and MYB, the transcription factor that positively regulates MIR155HG, were upregulated by RNA-seq and their promoters were more accessible by ATAC-seq. To evaluate the clinical impact of XPO1 mutations, we investigated a total of 957 early-stage CLL subdivided into 3 independent cohorts (N = 276, N = 286 and N = 395). Next-generation sequencing analysis identified XPO1 mutations as a novel predictor of shorter time to first treatment (TTFT) in all cohorts. Notably, XPO1 mutations maintained their prognostic value independent of the immunoglobulin heavy chain variable status and early-stage prognostic models. These data suggest that XPO1 mutations, conceivably through increased miR-155 levels, may enhance BCR signalling leading to higher proliferation and shorter TTFT in early-stage CLL.

2.
Br J Haematol ; 198(6): 1016-1022, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35829664

RESUMEN

Richter syndrome (RS) is mostly due to the direct transformation of the chronic lymphocytic leukaemia (CLL) clone, as documented by the same immunoglobulin heavy-chain variable region (IGHV) rearrangement in both CLL and RS cells. In rare cases characterized by a better outcome, the RS clone harbours a different IGHV rearrangement compared to the CLL phase. We investigated the CLL phase of clonally unrelated RS to test whether the RS clone was already identifiable prior to clinicopathologic transformation, albeit undetectable by conventional approaches. CLL cells of eight patients with unrelated RS were subjected to an ultra-deep next-generation sequencing (NGS) approach with a sensitivity of 10-6 . In 7/8 cases, the RS rearrangement was not identified in the CLL phase. In one case, the RS clone was identified at a very low frequency in the CLL phase, conceivably due to the concomitance of CLL sampling and RS diagnosis. Targeted resequencing revealed that clonally unrelated RS carries genetic lesions primarily affecting the TP53, MYC, ATM and NOTCH1 genes. Conversely, mutations frequently involved in de novo diffuse large B-cell lymphoma (DLBCL) without a history of CLL were absent. These results suggest that clonally unrelated RS is a truly de novo lymphoma with a mutational profile reminiscent, at least in part, of clonally related RS.


Asunto(s)
Leucemia Linfocítica Crónica de Células B , Linfoma de Células B Grandes Difuso , Aberraciones Cromosómicas , Humanos , Región Variable de Inmunoglobulina/genética , Leucemia Linfocítica Crónica de Células B/patología , Linfoma de Células B Grandes Difuso/genética , Linfoma de Células B Grandes Difuso/patología , Mutación
3.
Br J Haematol ; 195(1): 108-112, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34291829

RESUMEN

We aimed at molecularly dissecting the anatomical heterogeneity of small lymphocytic lymphoma (SLL), by analysing a cohort of 12 patients for whom paired DNA from a lymph node biopsy and circulating cells, as well as plasma-circulating tumour DNA (ctDNA) was available. Notably, the analyses of the lymph node biopsy and of circulating cells complement each other since a fraction of mutations (20·4% and 36·4%, respectively) are unique to each compartment. Plasma ctDNA identified two additional unique mutations. Consistently, the different synchronous sources of tumour DNA complement each other in informing on driver gene mutations in SLL harbouring potential prognostic and/or predictive value.


Asunto(s)
Aberraciones Cromosómicas , ADN de Neoplasias/sangre , Leucemia Linfocítica Crónica de Células B/patología , Ganglios Linfáticos/patología , Adenina/análogos & derivados , Adenina/uso terapéutico , Anciano , Biopsia , Deleción Cromosómica , Cromosomas Humanos Par 12 , Cromosomas Humanos Par 13/ultraestructura , Cromosomas Humanos Par 17/ultraestructura , Variaciones en el Número de Copia de ADN , ADN de Neoplasias/análisis , Femenino , Genes de Inmunoglobulinas , Humanos , Cadenas Pesadas de Inmunoglobulina/genética , Inmunoterapia , Leucemia Linfocítica Crónica de Células B/sangre , Leucemia Linfocítica Crónica de Células B/genética , Ganglios Linfáticos/química , Masculino , Persona de Mediana Edad , Mutación , Piperidinas/uso terapéutico
4.
Haematologica ; 105(2): 448-456, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31371416

RESUMEN

BIRC3 is a recurrently mutated gene in chronic lymphocytic leukemia (CLL) but the functional implications of BIRC3 mutations are largely unexplored. Furthermore, little is known about the prognostic impact of BIRC3 mutations in CLL cohorts homogeneously treated with first-line fludarabine, cyclophosphamide, and rituximab (FCR). By immunoblotting analysis, we showed that the non-canonical nuclear factor-κB pathway is active in BIRC3-mutated cell lines and in primary CLL samples, as documented by the stabilization of MAP3K14 and by the nuclear localization of p52. In addition, BIRC3-mutated primary CLL cells are less sensitive to flu-darabine. In order to confirm in patients that BIRC3 mutations confer resistance to fludarabine-based chemoimmunotherapy, a retrospective multicenter cohort of 287 untreated patients receiving first-line FCR was analyzed by targeted next-generation sequencing of 24 recurrently mutated genes in CLL. By univariate analysis adjusted for multiple comparisons BIRC3 mutations identify a poor prognostic subgroup of patients in whom FCR treatment fails (median progression-free survival: 2.2 years, P<0.001) similar to cases harboring TP53 mutations (median progression-free survival: 2.6 years, P<0.0001). BIRC3 mutations maintained an independent association with an increased risk of progression with a hazard ratio of 2.8 (95% confidence interval 1.4-5.6, P=0.004) in multivariate analysis adjusted for TP53 mutation, 17p deletion and IGHV mutation status. If validated, BIRC3 mutations may be used as a new molecular predictor to select high-risk patients for novel frontline therapeutic approaches.


Asunto(s)
Leucemia Linfocítica Crónica de Células B , Protocolos de Quimioterapia Combinada Antineoplásica , Proteína 3 que Contiene Repeticiones IAP de Baculovirus , Ciclofosfamida/uso terapéutico , Humanos , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/genética , Mutación , Pronóstico , Estudios Retrospectivos , Rituximab/uso terapéutico
5.
Blood ; 129(14): 1947-1957, 2017 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-28096087

RESUMEN

Accessible and real-time genotyping for diagnostic, prognostic, or treatment purposes is increasingly impelling in diffuse large B-cell lymphoma (DLBCL). Cell-free DNA (cfDNA) is shed into the blood by tumor cells undergoing apoptosis and can be used as source of tumor DNA for the identification of DLBCL mutations, clonal evolution, and genetic mechanisms of resistance. In this study, we aimed at tracking the basal DLBCL genetic profile and its modification upon treatment using plasma cfDNA. Ultra-deep targeted next generation sequencing of pretreatment plasma cfDNA from DLBCL patients correctly discovered DLBCL-associated mutations that were represented in >20% of the alleles of the tumor biopsy with >90% sensitivity and ∼100% specificity. Plasma cfDNA genotyping also allowed for the recovery of mutations that were undetectable in the tissue biopsy, conceivably because, due to spatial tumor heterogeneity, they were restricted to clones that were anatomically distant from the biopsy site. Longitudinal analysis of plasma samples collected under rituximab-cyclophosphamide-doxorubicin-vincristine-prednisone (R-CHOP) chemotherapy showed a rapid clearance of DLBCL mutations from cfDNA among responding patients. Conversely, among patients who were resistant to R-CHOP, basal DLBCL mutations did not disappear from cfDNA. In addition, among treatment-resistant patients, new mutations were acquired in cfDNA that marked resistant clones selected during the clonal evolution. These results demonstrate that cfDNA genotyping of DLBCL is as accurate as genotyping of the diagnostic biopsy to detect clonally represented somatic tumor mutations and is a real-time and noninvasive approach to tracking clonal evolution and the emergence of treatment-resistant clones.


Asunto(s)
Técnicas de Genotipaje , Secuenciación de Nucleótidos de Alto Rendimiento , Linfoma de Células B Grandes Difuso/genética , Mutación , Anticuerpos Monoclonales de Origen Murino/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Biopsia , Ciclofosfamida/administración & dosificación , Doxorrubicina/administración & dosificación , Femenino , Estudios de Seguimiento , Humanos , Linfoma de Células B Grandes Difuso/sangre , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Linfoma de Células B Grandes Difuso/patología , Masculino , Prednisona/administración & dosificación , Estudios Prospectivos , Rituximab , Vincristina/administración & dosificación
7.
Blood ; 123(15): 2378-88, 2014 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-24550227

RESUMEN

Fludarabine refractoriness (FR) represents an unsolved clinical problem of chronic lymphocytic leukemia (CLL) management. Although next-generation sequencing studies have led to the identification of a number of genes frequently mutated in FR-CLL, a comprehensive evaluation of the FR-CLL genome has not been reported. Toward this end, we studied 10 FR-CLLs by combining whole-exome sequencing and copy number aberration (CNA) analysis, which showed an average of 16.3 somatic mutations and 4 CNAs per sample. Screening of recurrently mutated genes in 48 additional FR-CLLs revealed that ~70% of FR-CLLs carry ≥1 mutation in genes previously associated with CLL clinical course, including TP53 (27.5%), NOTCH1 (24.1%), SF3B1 (18.9%), and BIRC3 (15.5%). In addition, this analysis showed that 10.3% of FR-CLL cases display mutations of the FAT1 gene, which encodes for a cadherin-like protein that negatively regulates Wnt signaling, consistent with a tumor suppressor role. The frequency of FAT1-mutated cases was significantly higher in FR-CLL than in unselected CLLs at diagnosis (10.3% vs 1.1%, P = .004), suggesting a role in the development of a high-risk phenotype. These findings have general implications for the mechanisms leading to FR and point to Wnt signaling as a potential therapeutic target in FR-CLL.


Asunto(s)
Cadherinas/genética , Resistencia a Antineoplásicos/genética , Leucemia Linfocítica Crónica de Células B/genética , Anciano , Análisis Mutacional de ADN , Femenino , Genotipo , Humanos , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Mutación , Transcriptoma
8.
Blood ; 123(14): 2139-47, 2014 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-24501221

RESUMEN

TP53 mutations are strong predictors of poor survival and refractoriness in chronic lymphocytic leukemia (CLL) and have direct implications for disease management. Clinical information on TP53 mutations is limited to lesions represented in >20% leukemic cells. Here, we tested the clinical impact and prediction of chemorefractoriness of very small TP53 mutated subclones. The TP53 gene underwent ultra-deep-next generation sequencing (NGS) in 309 newly diagnosed CLL. A robust bioinformatic algorithm was established for the highly sensitive detection of few TP53 mutated cells (down to 3 out of ∼1000 wild-type cells). Minor subclones were validated by independent approaches. Ultra-deep-NGS identified small TP53 mutated subclones in 28/309 (9%) untreated CLL that, due to their very low abundance (median allele frequency: 2.1%), were missed by Sanger sequencing. Patients harboring small TP53 mutated subclones showed the same clinical phenotype and poor survival (hazard ratio = 2.01; P = .0250) as those of patients carrying clonal TP53 lesions. By longitudinal analysis, small TP53 mutated subclones identified before treatment became the predominant population at the time of CLL relapse and anticipated the development of chemorefractoriness. This study provides a proof-of-principle that very minor leukemia subclones detected at diagnosis are an important driver of the subsequent disease course.


Asunto(s)
Leucemia Linfocítica Crónica de Células B/genética , Leucemia Linfocítica Crónica de Células B/mortalidad , Proteína p53 Supresora de Tumor/genética , Adulto , Anciano , Anciano de 80 o más Años , Células Clonales/metabolismo , Células Clonales/patología , Resistencia a Antineoplásicos/genética , Femenino , Humanos , Leucemia Linfocítica Crónica de Células B/patología , Masculino , Persona de Mediana Edad , Mutación , Pronóstico , Análisis de Supervivencia
9.
Blood ; 121(8): 1403-12, 2013 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-23243274

RESUMEN

The identification of new genetic lesions in chronic lymphocytic leukemia (CLL) prompts a comprehensive and dynamic prognostic algorithm including gene mutations and chromosomal abnormalities and their changes during clonal evolution. By integrating mutational and cytogenetic analysis in 1274 CLL samples and using both a training-validation and a time-dependent design, 4 CLL subgroups were hierarchically classified: (1) high-risk, harboring TP53 and/or BIRC3 abnormalities (10-year survival: 29%); (2) intermediate-risk, harboring NOTCH1 and/or SF3B1 mutations and/or del11q22-q23 (10-year survival: 37%); (3) low-risk, harboring +12 or a normal genetics (10-year survival: 57%); and (4) very low-risk, harboring del13q14 only, whose 10-year survival (69.3%) did not significantly differ from a matched general population. This integrated mutational and cytogenetic model independently predicted survival, improved CLL prognostication accuracy compared with FISH karyotype (P < .0001), and was externally validated in an independent CLL cohort. Clonal evolution from lower to higher risk implicated the emergence of NOTCH1, SF3B1, and BIRC3 abnormalities in addition to TP53 and 11q22-q23 lesions. By taking into account clonal evolution through time-dependent analysis, the genetic model maintained its prognostic relevance at any time from diagnosis. These findings may have relevant implications for the design of clinical trials aimed at assessing the use of mutational profiling to inform therapeutic decisions.


Asunto(s)
Proteínas Inhibidoras de la Apoptosis/genética , Leucemia Linfocítica Crónica de Células B/genética , Leucemia Linfocítica Crónica de Células B/mortalidad , Fosfoproteínas/genética , Receptor Notch1/genética , Ribonucleoproteína Nuclear Pequeña U2/genética , Proteína p53 Supresora de Tumor/genética , Algoritmos , Proteína 3 que Contiene Repeticiones IAP de Baculovirus , Análisis Mutacional de ADN , Educación Médica Continua , Femenino , Pruebas Genéticas , Humanos , Estimación de Kaplan-Meier , Leucemia Linfocítica Crónica de Células B/diagnóstico , Masculino , Modelos Genéticos , Factor 88 de Diferenciación Mieloide/genética , Pronóstico , Factores de Empalme de ARN , Factores de Riesgo , Ubiquitina-Proteína Ligasas
10.
Blood ; 121(24): 4902-5, 2013 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-23637131

RESUMEN

Genetic lesions and B-cell receptor (BCR) signaling are both oncogenic drivers in chronic lymphocytic leukemia (CLL). However, scant data are available on preferential associations between specific genetic alterations and stereotyped BCR subsets. By analyzing 1419 cases, 2 CLL subsets (2 and 8) harboring stereotyped BCR are enriched in specific molecular alterations influencing disease course. SF3B1 mutations are the genetic hallmark of IGHV3-21-CLL belonging to subset 2 (52%) but are evenly represented in nonstereotyped IGHV3-21-CLL. Trisomy 12 (87%) and NOTCH1 mutations (62%) characterize IGHV4-39-CLL belonging to subset 8 but occur with the expected frequency in IGHV4-39-CLL with heterogeneous BCR. Clinically, co-occurrence of SF3B1 mutations and subset 2 BCR configuration prompts disease progression in IGHV3-21-CLL, whereas cooperation between NOTCH1 mutations, +12, and subset 8 BCR configuration invariably primes CLL transformation into Richter syndrome. These findings provide a proof of concept that specific stereotyped BCR may promote or select molecular lesions influencing outcome.


Asunto(s)
Subgrupos de Linfocitos B , Leucemia Linfocítica Crónica de Células B , Fosfoproteínas/genética , Mutación Puntual , Receptor Notch1/genética , Receptores de Antígenos de Linfocitos B/genética , Ribonucleoproteína Nuclear Pequeña U2/genética , Adulto , Anciano , Subgrupos de Linfocitos B/metabolismo , Subgrupos de Linfocitos B/patología , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Leucemia Linfocítica Crónica de Células B/genética , Leucemia Linfocítica Crónica de Células B/mortalidad , Leucemia Linfocítica Crónica de Células B/patología , Leucemia Linfocítica Crónica de Células B/terapia , Masculino , Persona de Mediana Edad , Factores de Empalme de ARN , Estudios Retrospectivos , Tasa de Supervivencia
11.
Blood ; 119(2): 521-9, 2012 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-22077063

RESUMEN

Analysis of the chronic lymphocytic leukemia (CLL) coding genome has recently disclosed that the NOTCH1 proto-oncogene is recurrently mutated at CLL presentation. Here, we assessed the prognostic role of NOTCH1 mutations in CLL. Two series of newly diagnosed CLL were used as training (n = 309) and validation (n = 230) cohorts. NOTCH1 mutations occurred in 11.0% and 11.3% CLL of the training and validation series, respectively. In the training series, NOTCH1 mutations led to a 3.77-fold increase in the hazard of death and to shorter overall survival (OS; P < .001). Multivariate analysis selected NOTCH1 mutations as an independent predictor of OS after controlling for confounding clinical and biologic variables. The independent prognostic value of NOTCH1 mutations was externally confirmed in the validation series. The poor prognosis conferred by NOTCH1 mutations was attributable, at least in part, to shorter treatment-free survival and higher risk of Richter transformation. Although NOTCH1 mutated patients were devoid of TP53 disruption in more than 90% cases in both training and validation series, the OS predicted by NOTCH1 mutations was similar to that of TP53 mutated/deleted CLL. NOTCH1 mutations are an independent predictor of CLL OS, tend to be mutually exclusive with TP53 abnormalities, and identify cases with a dismal prognosis.


Asunto(s)
Leucemia Linfocítica Crónica de Células B/genética , Leucemia Linfocítica Crónica de Células B/mortalidad , Mutación/genética , Receptor Notch1/genética , Anciano , Transformación Celular Neoplásica , Cromosomas Humanos Par 12/genética , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Cadenas Pesadas de Inmunoglobulina/genética , Región Variable de Inmunoglobulina/genética , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Proto-Oncogenes Mas , Factores de Riesgo , Tasa de Supervivencia , Proteína p53 Supresora de Tumor/genética
12.
Blood ; 119(12): 2854-62, 2012 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-22308293

RESUMEN

The genetic lesions identified to date do not fully recapitulate the molecular pathogenesis of chronic lymphocytic leukemia (CLL) and do not entirely explain the development of severe complications such as chemorefractoriness. In the present study, BIRC3, a negative regulator of noncanonical NF-κB signaling, was investigated in different CLL clinical phases. BIRC3 lesions were absent in monoclonal B-cell lymphocytosis (0 of 63) and were rare in CLL at diagnosis (13 of 306, 4%). Conversely, BIRC3 disruption selectively affected 12 of 49 (24%) fludarabine-refractory CLL cases by inactivating mutations and/or gene deletions that distributed in a mutually exclusive fashion with TP53 abnormalities. In contrast to fludarabine-refractory CLL, progressive but fludarabine-sensitive patients were consistently devoid of BIRC3 abnormalities, suggesting that BIRC3 genetic lesions associate specifically with a chemorefractory phenotype. By actuarial analysis in newly diagnosed CLL (n = 306), BIRC3 disruption identified patients with a poor outcome similar to that associated with TP53 abnormalities and exerted a prognostic role that was independent of widely accepted clinical and genetic risk factors. Consistent with the role of BIRC3 as a negative regulator of NF-κB, biochemical studies revealed the presence of constitutive noncanonical NF-κB activation in fludarabine-refractory CLL patients harboring molecular lesions of BIRC3. These data identify BIRC3 disruption as a recurrent genetic lesion of high-risk CLL devoid of TP53 abnormalities.


Asunto(s)
Antineoplásicos/uso terapéutico , Resistencia a Antineoplásicos/genética , Proteínas Inhibidoras de la Apoptosis/genética , Leucemia Linfocítica Crónica de Células B/genética , Proteína p53 Supresora de Tumor/genética , Vidarabina/análogos & derivados , Anciano , Proteína 3 que Contiene Repeticiones IAP de Baculovirus , Western Blotting , Análisis Mutacional de ADN , Femenino , Humanos , Hibridación Fluorescente in Situ , Proteínas Inhibidoras de la Apoptosis/metabolismo , Estimación de Kaplan-Meier , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/mortalidad , Masculino , Persona de Mediana Edad , FN-kappa B/metabolismo , Pronóstico , Modelos de Riesgos Proporcionales , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Ubiquitina-Proteína Ligasas , Vidarabina/uso terapéutico
13.
Blood ; 117(12): 3391-401, 2011 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-21266718

RESUMEN

Richter syndrome (RS) represents the development of diffuse large B-cell lymphoma in the context of chronic lymphocytic leukemia. The scarcity of biologic information about RS has hampered the identification of molecular predictors of RS outcome. We addressed this issue by performing a comprehensive molecular characterization of 86 pathologically proven RS. TP53 disruption (47.1%) and c-MYC abnormalities (26.2%) were the most frequent alterations, whereas common genetic lesions of de novo diffuse large B-cell lymphoma were rare or absent. By multivariate analysis, lack of TP53 disruption (hazard ratio, 0.43; P = .003) translated into significant survival advantage with 57% reduction in risk of death. An algorithm based on TP53 disruption, response to RS treatment, and Eastern Cooperative Oncology Group performance status had 80.9% probability of correctly discriminating RS survival (c-index = .809). RS that were clonally unrelated to the paired chronic lymphocytic leukemia phase were clinically and biologically different from clonally related RS because of significantly longer survival (median, 62.5 months vs 14.2 months; P = .017) and lower prevalence of TP53 disruption (23.1% vs 60.0%; P = .018) and B-cell receptor stereotypy (7.6% vs 50.0%; P = .009). The molecular dissection of RS into biologically distinct categories highlights the genetic heterogeneity of this disorder and provides clinically relevant information for refining the prognostic stratification of patients.


Asunto(s)
Transformación Celular Neoplásica/genética , Heterogeneidad Genética , Síndromes de Inmunodeficiencia/genética , Síndromes de Inmunodeficiencia/mortalidad , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Estudios de Cohortes , Femenino , Genes p53/genética , Humanos , Síndromes de Inmunodeficiencia/complicaciones , Síndromes de Inmunodeficiencia/diagnóstico , Masculino , Persona de Mediana Edad , Técnicas de Diagnóstico Molecular , Estudios Multicéntricos como Asunto , Mutación/fisiología , Pronóstico , Análisis de Supervivencia
14.
Blood ; 118(18): 4930-4, 2011 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-21881048

RESUMEN

Splenic marginal zone lymphoma (SMZL) is one of the few B-cell lymphoma types that remain orphan of molecular lesions in cancer-related genes. Detection of active NF-κB signaling in 14 (58%) of 24 SMZLs prompted the investigation of NF-κB molecular alterations in 101 SMZLs. Mutations and copy number abnormalities of NF-κB genes occurred in 36 (36%) of 101 SMZLs and targeted both canonical (TNFAIP3 and IKBKB) and noncanonical (BIRC3, TRAF3, MAP3K14) NF-κB pathways. Most alterations were mutually exclusive, documenting the existence of multiple independent mechanisms affecting NF-κB in SMZL. BIRC3 inactivation in SMZL recurred because of somatic mutations that disrupted the same RING domain that in extranodal marginal zone lymphoma is removed by the t(11;18) translocation, which points to BIRC3 disruption as a common mechanism across marginal zone B-cell lymphomagenesis. Genetic lesions of NF-κB provide a molecular basis for the pathogenesis of more than 30% of SMZLs and offer a suitable target for NF-κB therapeutic approaches in this lymphoma.


Asunto(s)
Proteínas Inhibidoras de la Apoptosis/genética , Linfoma de Células B de la Zona Marginal/genética , FN-kappa B/metabolismo , Neoplasias del Bazo/genética , Proteína 3 que Contiene Repeticiones IAP de Baculovirus , Estudios de Casos y Controles , Análisis por Conglomerados , Análisis Mutacional de ADN , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Proteínas Inhibidoras de la Apoptosis/metabolismo , Análisis por Micromatrices , Modelos Biológicos , FN-kappa B/genética , Transducción de Señal/genética , Ubiquitina-Proteína Ligasas
15.
Blood ; 118(26): 6904-8, 2011 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-22039264

RESUMEN

The genetic lesions identified in chronic lymphocytic leukemia (CLL) do not entirely recapitulate the disease pathogenesis and the development of serious complications, such as chemorefractoriness. While investigating the coding genome of fludarabine-refractory CLL, we observed that mutations of SF3B1, encoding a splicing factor and representing a critical component of the cell spliceosome, were recurrent in 10 of 59 (17%) fludarabine-refractory cases, with a frequency significantly greater than that observed in a consecutive CLL cohort sampled at diagnosis (17/301, 5%; P = .002). Mutations were somatically acquired, were generally represented by missense nucleotide changes, clustered in selected HEAT repeats of the SF3B1 protein, recurrently targeted 3 hotspots (codons 662, 666, and 700), and were predictive of a poor prognosis. In fludarabine-refractory CLL, SF3B1 mutations and TP53 disruption distributed in a mutually exclusive fashion (P = .046). The identification of SF3B1 mutations points to splicing regulation as a novel pathogenetic mechanism of potential clinical relevance in CLL.


Asunto(s)
Leucemia Linfocítica Crónica de Células B/genética , Mutación , Fosfoproteínas/genética , Ribonucleoproteína Nuclear Pequeña U2/genética , Secuencia de Aminoácidos , Antineoplásicos/uso terapéutico , Análisis Mutacional de ADN , Progresión de la Enfermedad , Resistencia a Antineoplásicos , Perfilación de la Expresión Génica , Regulación Leucémica de la Expresión Génica , Humanos , Hibridación Fluorescente in Situ , Cariotipificación , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/patología , Datos de Secuencia Molecular , Análisis de Secuencia por Matrices de Oligonucleótidos , Polimorfismo de Nucleótido Simple , Factores de Empalme de ARN , Homología de Secuencia de Aminoácido , Empalmosomas/genética , Proteína p53 Supresora de Tumor/genética , Vidarabina/análogos & derivados , Vidarabina/uso terapéutico
16.
Blood ; 117(8): 2405-13, 2011 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-21156845

RESUMEN

Several drugs used for diffuse large B-cell lymphoma (DLBCL) treatment rely on DNA damage for tumor cell killing. We verified the prognostic impact of the host DNA repair genotype in 2 independent cohorts of DLBCL treated with R-CHOP21 (training cohort, 163 cases; validation cohort, 145 cases). Among 35 single nucleotide polymorphisms analyzed in the training series, MLH1 rs1799977 was the sole predicting overall survival. DLBCL carrying the MLH1 AG/GG genotype displayed an increased death risk (hazard ratio [HR] = 3.23; P < .001; q =0 .009) compared with patients carrying the AA genotype. Multivariate analysis adjusted for International Prognostic Index identified MLH1 AG/GG as an independent OS predictor (P < .001). The poor prognosis of MLH1 AG/GG was the result of an increased risk of failing both R-CHOP21 (HR = 2.02; P = .007) and platinum-based second-line (HR = 2.26; P = .044) treatment. Survival analysis in the validation series confirmed all outcomes predicted by MLH1 rs1799977. The effect on OS of MLH1, a component of the DNA mismatch repair system, is consistent with its role in regulating the genotoxic effects of doxorubicin and platinum compounds, which are a mainstay of DLBCL first- and second-line treatment.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Reparación del ADN/genética , Linfoma de Células B Grandes Difuso/genética , Linfoma de Células B Grandes Difuso/mortalidad , Proteínas Nucleares/genética , Farmacogenética/métodos , Polimorfismo de Nucleótido Simple , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Inteligencia Artificial , Ciclofosfamida/uso terapéutico , Doxorrubicina/uso terapéutico , Genotipo , Humanos , Homólogo 1 de la Proteína MutL , Compuestos de Platino , Medicina de Precisión , Valor Predictivo de las Pruebas , Prednisona/uso terapéutico , Pronóstico , Medición de Riesgo , Tasa de Supervivencia , Vincristina/uso terapéutico
17.
Int J Cancer ; 130(12): 3006-10, 2012 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-21796624

RESUMEN

Richter syndrome (RS) represents the transformation of chronic lymphocytic leukemia to aggressive lymphoma. We explored intraclonal diversification (ID) of immunoglobulin genes in order to (i) follow the evolutionary history of the RS clone (ii) compare the role of ID in clonally related RS vs. clonally unrelated cases. Most (10/11, 90.9%) clonally related RS stem from the predominant clone observed at CLL diagnosis. One single RS had a transformation pattern compatible with sequential evolution from a secondary CLL subclone. Once RS transformation had occurred, all secondary CLL subclones disappeared and were substituted by the dominant RS clone with its own descendants. These observations suggest that genetic lesions associated with RS transformation are acquired by a cell belonging to the original CLL clone, rather than being progressively accumulated by later CLL subclones. Accordingly, most (9/11, 81.1%) clonally related RS harbored a genetic lesion disrupting TP53 that was already present, though at subclonal levels, in 5/11 (45.5%) samples of the paired CLL phase. A fraction of clonally related RS switched off ID (4/11, 36.4%) or reduced the levels of ID (5/11, 45.4%) at transformation. Conversely, all clonally unrelated RS harbored ID and were characterized by a significantly higher mutation frequency compared to clonally related RS (median: 1.18 × 10(-3) vs. 0.13 × 10(-3); p =0.002). These data indicate that (i) clonally related RS stems from a cell that is already present within the initial CLL clone and (ii) clonally unrelated and clonally related RS are biologically distinct disorders also in terms of antigen affinity maturation.


Asunto(s)
Genes de Inmunoglobulinas , Inmunoglobulinas/genética , Leucemia Linfocítica Crónica de Células B/genética , Linfoma/genética , Linfoma/patología , Transformación Celular Neoplásica/genética , Genes p53 , Humanos , Leucemia Linfocítica Crónica de Células B/diagnóstico , Leucemia Linfocítica Crónica de Células B/patología , Linfoma/etiología , Mutación , Tasa de Mutación , Proteína p53 Supresora de Tumor/genética
18.
Haematologica ; 97(3): 437-41, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22207691

RESUMEN

Trisomy 12, the third most frequent chromosomal aberration in chronic lymphocytic leukemia (CLL), confers an intermediate prognosis. In our cohort of 104 untreated patients carrying +12, NOTCH1 mutations occurred in 24% of cases and were associated to unmutated IGHV genes (P=0.003) and +12 as a sole cytogenetic abnormality (P=0.008). NOTCH1 mutations in +12 CLL associated with an approximately 2.4 fold increase in the risk of death, a significant shortening of survival (P<0.01) and proved to be an independent predictor of survival in multivariate analysis. Analogous to +12 CLL with TP53 disruption or del(11q), NOTCH1 mutations in +12 CLL conferred a significantly worse survival compared to that of +12 CLL with del(13q) or +12 only. The overrepresentation of cell cycle/proliferation related genes of +12 CLL with NOTCH1 mutations suggests the biological contribution of NOTCH1 mutations to determine a poor outcome. NOTCH1 mutations refine the intermediate prognosis of +12 CLL.


Asunto(s)
Cromosomas Humanos Par 12 , Perfilación de la Expresión Génica , Leucemia Linfocítica Crónica de Células B/genética , Mutación , Receptor Notch1/genética , Transcripción Genética , Trisomía , Anciano , Femenino , Humanos , Leucemia Linfocítica Crónica de Células B/mortalidad , Masculino , Persona de Mediana Edad , Tasa de Mutación , Pronóstico , Análisis de Supervivencia
19.
ACS Appl Mater Interfaces ; 14(43): 48582-48597, 2022 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-36269760

RESUMEN

Research involved in developing alternative energy sources has become a necessity to face global warming. In this context, superconductivity is an appealing solution to enhance clean electrical energy provided that lower production costs can be attained. By implementation of chemical solution deposition techniques and high-throughput growth methods, low-cost nanostructured epitaxial cuprate superconductors are timely candidates. Here, we present a versatile and tunable solution method suitable for the preparation of high-performance epitaxial cuprate superconducting films. Disregarding the renowned trifluoroacetate route, we center our focus on the transient liquid-assisted growth (TLAG) that meets the requirement of being a greener chemical process together with ultrafast growth rates beyond 100 nm/s. We developed a facile, fast, and cost-effective method, starting from the synthesis of metal-propionate powders of Y, Ba, and Cu of high purity and high yields, being the precursors of the fluorine-free solutions, which enable the chemical and microstructural nanoscale homogeneity of YBa2Cu3O7-x (YBCO) precursor films. These solutions present endured stability and enable precise tunability of the composition, concentration, porosity, and film thickness. Homogeneous precursor films up to thicknesses of 2.7 µm through eight layer multidepositions are demonstrated, thus establishing the correct basis for epitaxial growth using the fast kinetics of the TLAG process. YBCO films of 500 nm thickness with a critical current density of 2.6 MA/cm2 at 77 K were obtained, showing the correlation of precursor film homogeneity to the final YBCO physical properties.

20.
Adv Sci (Weinh) ; 9(32): e2203834, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36116124

RESUMEN

Transient liquid assisted growth (TLAG) is an ultrafast non-equilibrium growth process mainly governed by kinetic parameters, which are only accessible through fast in situ characterizations. In situ synchrotron X-ray diffraction (XRD) analysis and in situ electrical resistivity measurements are used to derive kinetic diagrams of YBa2 Cu3 O7- x (YBCO) superconducting films prepared via TLAG and to reveal the unique peculiarities of the process. In particular, diagrams for the phase evolution and the YBCO growth rates have been built for the two TLAG routes. It is shown that TLAG transient liquids can be obtained upon the melting of two barium cuprate phases (and not just one), differentiated by their copper oxidation state. This knowledge serves as a guide to determine the processing conditions to reach high performance films at high growth rates. With proper control of these kinetic parameters, films with critical current densities of 2-2.6 MA cm-2 at 77 K and growth rates between 100-2000 nm s-1 are reached. These growth rates are 1.5-3 orders of magnitude higher than those of conventional methods.

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