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1.
Ann Oncol ; 27(1): 62-8, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26504152

RESUMEN

The treatment of patients with myelodysplastic syndromes (MDS) begins with assessment of karyotype and risk. Lenalidomide is approved for the treatment of patients who have transfusion-dependent anemia due to lower-risk MDS with chromosome 5q deletion (del(5q)) with or without additional cytogenetic abnormalities, and isolated del(5q) only in the European Union. Mounting evidence suggests that lenalidomide is effective not only in reducing red blood cell (RBC) transfusion burden, but also in modifying the disease natural history by suppressing the malignant clone. Data discussed here from the pivotal phase 2 (MDS-003) and phase 3 (MDS-004) studies of lenalidomide demonstrate that lenalidomide treatment was associated with both short- and long-term benefits. These clinical benefits included high rates of RBC-transfusion independence (TI) with prolonged durations of response, high rates of cytogenetic response (CyR) associated with achievement of durable RBC-TI, no significant difference in rates of progression to acute myeloid leukemia (AML), and improvements in health-related quality of life (HRQOL). Achievement of RBC-TI and CyR with lenalidomide treatment was associated with extended survival and time to AML progression. Achievement of RBC-TI and hemoglobin response was additionally associated with HRQOL benefits. Recent data describing the impact of TP53 mutations and p53 expression on the prognosis of patients with del(5q) and the impact on response to lenalidomide are also discussed. The authors provide practical recommendations for the use of lenalidomide in patients with lower-risk del(5q) MDS.


Asunto(s)
Inhibidores de la Angiogénesis/uso terapéutico , Síndromes Mielodisplásicos/tratamiento farmacológico , Talidomida/análogos & derivados , Deleción Cromosómica , Humanos , Lenalidomida , Síndromes Mielodisplásicos/genética , Riesgo , Talidomida/uso terapéutico , Resultado del Tratamiento
2.
Leukemia ; 35(3): 835-849, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32595214

RESUMEN

In the current World Health Organization (WHO)-classification, therapy-related myelodysplastic syndromes (t-MDS) are categorized together with therapy-related acute myeloid leukemia (AML) and t-myelodysplastic/myeloproliferative neoplasms into one subgroup independent of morphologic or prognostic features. Analyzing data of 2087 t-MDS patients from different international MDS groups to evaluate classification and prognostication tools we found that applying the WHO classification for p-MDS successfully predicts time to transformation and survival (both p < 0.001). The results regarding carefully reviewed cytogenetic data, classifications, and prognostic scores confirmed that t-MDS are similarly heterogeneous as p-MDS and therefore deserve the same careful differentiation regarding risk. As reference, these results were compared with 4593 primary MDS (p-MDS) patients represented in the International Working Group for Prognosis in MDS database (IWG-PM). Although a less favorable clinical outcome occurred in each t-MDS subset compared with p-MDS subgroups, FAB and WHO-classification, IPSS-R, and WPSS-R separated t-MDS patients into differing risk groups effectively, indicating that all established risk factors for p-MDS maintained relevance in t-MDS, with cytogenetic features having enhanced predictive power. These data strongly argue to classify t-MDS as a separate entity distinct from other WHO-classified t-myeloid neoplasms, which would enhance treatment decisions and facilitate the inclusion of t-MDS patients into clinical studies.


Asunto(s)
Biomarcadores de Tumor/análisis , Síndromes Mielodisplásicos/clasificación , Síndromes Mielodisplásicos/diagnóstico , Neoplasias Primarias Secundarias/clasificación , Neoplasias Primarias Secundarias/diagnóstico , Medición de Riesgo/métodos , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/terapia , Neoplasias Primarias Secundarias/terapia , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia
3.
Cancer Invest ; 27(9): 932-6, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19832041

RESUMEN

This study aim was to determine the efficacy and safety of the combination of Gemcitabine 1000 mg/m(2) day 1 & 8 and Irinotecan 100 mg/m(2) day 1 & 8 with escalating dose of thalidomide in chemonaive patients with advanced non-small cell lung cancer. Among the 20 patients who met eligibility criteria and received treatment, two patients (10%) experienced partial response and 14 (70%) experienced stable disease. The median time to disease progression was 4 months (95% CI: 2.8-6.6). The 1 year and 2 year survival rates were 36% and 27%, respectively. This combination is active in advanced NSCLC with manageable toxicity profile.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Camptotecina/administración & dosificación , Camptotecina/análogos & derivados , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/patología , Desoxicitidina/administración & dosificación , Desoxicitidina/análogos & derivados , Femenino , Humanos , Irinotecán , Estimación de Kaplan-Meier , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Talidomida/administración & dosificación , Factores de Tiempo , Resultado del Tratamiento , Gemcitabina
4.
Curr Oncol ; 15(6): 271-8, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19079627

RESUMEN

OBJECTIVES: Locally advanced breast cancer (LABC) poses a difficult clinical challenge with an overall poor long-term prognosis. The strength of the association between tumour characteristics, treatment response, and outcome is not well defined. In the present study, we attempted to gain further insight into LABC by reviewing tumour characteristics of patients treated with neoadjuvant chemotherapy and by studying the association of those characteristics with outcome. We calculated the residual cancer burden (RCB) score obtained at surgery and attempted to study its correlation with event-free survival (EFS) and overall survival (OS). METHODS: We studied patients diagnosed primarily with LABC (n = 45). Pathologic and clinical responses were determined. Pathology slides were reviewed. RESULTS: Of the 45 study patients, 9% had stage IIB disease; 29%, stage IIIA; 51%, stage IIIB; and 11%, stage IIIC. Inflammatory breast cancer (IBC) was found in 16%. Pathologic complete response (pCR) was achieved in 22% of all patients. None of the patients with ibc achieved pcr. Patients with estrogen receptor-negative (ER-)/progesterone receptor-negative (PR-) tumours were more likely to achieve pcr than were those with ER+/PR+ tumours. Among patients with tumours that overexpressed human epidermal growth factor receptor 2 (HER2/neu), 17% achieved pCR as compared with 25% of patients with non-overexpressing tumours; only 1 patient had received trastuzumab. The RCB scores were calculated in 32 patients and ranged between 0 and 4.6. CONCLUSIONS: The present study examined practical issues related to the classification and management of LABC and IBC. The RCB, defined from routine pathology materials, was easily quantifiable. It appears to be a better predictor than pCR of outcome following neoadjuvant chemotherapy in LABC. Higher RCB scores were associated with lower efs and a lower rate of os. A continual quest for reliable predictive and correlative prognostic markers, and for better surrogate endpoints for outcome, is essential to advance our understanding of LABC and to improve treatment outcomes.

5.
Leukemia ; 32(2): 532-538, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28694526

RESUMEN

The interplay between tumor heterogeneity and microenvironmental factors is a critical mechanism for clonal selection in leukemia. Evidence of unique clonal capacities to engraft within patient-derived xenograft (PDX) models suggests that intrapatient genetic architecture may be defined by functional differences at the clonal level. However, methods to detect functional differences assigned to genetically defined clones remain limited. Here, we describe a scalable method to directly measure the functional properties of clones within the same leukemia patient by coupling intracellular flow cytometry and next-generation sequencing (NGS). We provide proof of concept utilizing primary chronic myelmonocytic leukemia (CMML) samples and granulocyte-macrophage colony stimulating factor (GM-CSF) to elucidate the interaction between tumor heterogeneity and microenvironmental factors. Mixtures of human leukemia cell lines, with known response to GM-CSF, were used to validate the accuracy of our methodology. Using this approach, we confirm that our method is capable of discriminating GM-CSF sensitive cell lines, identifies somatic variants in primary leukemia samples, and resolves functional clonal architecture in an illustrative patient. Taken together, our data describes a novel method to determine intrapatient functional clonal heterogeneity and provides proof-of-concept for future investigation aimed at elucidating the clinical relevance of functional clonal differences.


Asunto(s)
Citometría de Flujo/métodos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Leucemia/genética , Leucemia/patología , Factor Estimulante de Colonias de Granulocitos y Macrófagos/genética , Humanos , Células K562 , Células Tumorales Cultivadas
6.
Leukemia ; 31(10): 2172-2180, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28096534

RESUMEN

We recently reported that the accumulation of myeloid-derived suppressor cells (MDSC), defined as CD33+HLA-DR-Lin-, has a direct role in the pathogenesis of myelodysplastic syndrome (MDS). In particular, CD33 is strongly expressed in MDSC isolated from patients with MDS where it has an important role in MDSC-mediated hematopoietic suppressive function through its activation by S100A9. Therefore, we tested whether blocking this interaction with a fully human, Fc-engineered monoclonal antibody against CD33 (BI 836858) suppresses CD33-mediated signal transduction and improves the bone marrow microenvironment in MDS. We observed that BI 836858 can reduce MDSC by antibody-dependent cellular cytotoxicity, which correlated with increases in granule mobilization and cell death. BI 836858 can also block CD33 downstream signaling preventing immune-suppressive cytokine secretion, which correlates with a significant increase in the formation of CFU-GM and BFU-E colonies. Activation of the CD33 pathway can cause reactive oxygen species (ROS)-induced genomic instability but BI 836858 reduced both ROS and the levels of double strand breaks and adducts (measured by comet assay and γH2AX). This work provides the ground for the development of a novel group of therapies for MDS aimed at MDSC and their disease-promoting properties with the goal of improving hematopoiesis in patients.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Hematopoyesis/efectos de los fármacos , Fragmentos Fc de Inmunoglobulinas/uso terapéutico , Terapia Molecular Dirigida , Síndromes Mielodisplásicos/terapia , Células Supresoras de Origen Mieloide/efectos de los fármacos , Lectina 3 Similar a Ig de Unión al Ácido Siálico/inmunología , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales Humanizados , Citotoxicidad Celular Dependiente de Anticuerpos , Médula Ósea/patología , Femenino , Ingeniería Genética , Inestabilidad Genómica , Humanos , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/sangre , Síndromes Mielodisplásicos/inmunología , Síndromes Mielodisplásicos/patología , Células Supresoras de Origen Mieloide/inmunología , Especies Reactivas de Oxígeno , Transducción de Señal/efectos de los fármacos , Transducción de Señal/inmunología , Nicho de Células Madre
7.
Leukemia ; 31(6): 1391-1397, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28111463

RESUMEN

While therapy-related (t)-myelodysplastic syndromes (MDS) have worse outcomes than de novo MDS (d-MDS), some t-MDS patients have an indolent course. Most MDS prognostic models excluded t-MDS patients during development. The performances of the International Prognostic Scoring System (IPSS), revised IPSS (IPSS-R), MD Anderson Global Prognostic System (MPSS), WHO Prognostic Scoring System (WPSS) and t-MDS Prognostic System (TPSS) were compared among patients with t-MDS. Akaike information criteria (AIC) assessed the relative goodness of fit of the models. We identified 370 t-MDS patients (19%) among 1950 MDS patients. Prior therapy included chemotherapy alone (48%), chemoradiation (31%), and radiation alone in 21%. Median survival for t-MDS patients was significantly shorter than for d-MDS (19 vs 46 months, P<0.005). All models discriminated survival in t-MDS (P<0.005 for each model). Patients with t-MDS had a significantly higher hazard of death relative to d-MDS in every risk model, and had inferior survival compared to patients with d-MDS within all risk group categories. AIC Scores (lower is better) were 2316 (MPSS), 2343 (TPSS), 2343 (IPSS-R), 2361 (WPSS) and 2364 (IPSS). In conclusion, subsets of t-MDS patients with varying clinical outcomes can be identified using conventional risk stratification models. The MPSS, TPSS and IPSS-R provide the best predictive power.


Asunto(s)
Investigación Biomédica , Síndromes Mielodisplásicos/diagnóstico , Síndromes Mielodisplásicos/mortalidad , Medición de Riesgo/métodos , Terapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/terapia , Estadificación de Neoplasias , Pronóstico , Factores de Riesgo , Tasa de Supervivencia
8.
Leukemia ; 31(12): 2726-2731, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28561069

RESUMEN

Polycythemia vera (PV) and essential thrombocythemia (ET) are myeloproliferative neoplasms with variable risk of evolution into post-PV and post-ET myelofibrosis, from now on referred to as secondary myelofibrosis (SMF). No specific tools have been defined for risk stratification in SMF. To develop a prognostic model for predicting survival, we studied 685 JAK2, CALR, and MPL annotated patients with SMF. Median survival of the whole cohort was 9.3 years (95% CI: 8-not reached-NR-). Through penalized Cox regressions we identified negative predictors of survival and according to beta risk coefficients we assigned 2 points to hemoglobin level <11 g/dl, to circulating blasts ⩾3%, and to CALR-unmutated genotype, 1 point to platelet count <150 × 109/l and to constitutional symptoms, and 0.15 points to any year of age. Myelofibrosis Secondary to PV and ET-Prognostic Model (MYSEC-PM) allocated SMF patients into four risk categories with different survival (P<0.0001): low (median survival NR; 133 patients), intermediate-1 (9.3 years, 95% CI: 8.1-NR; 245 patients), intermediate-2 (4.4 years, 95% CI: 3.2-7.9; 126 patients), and high risk (2 years, 95% CI: 1.7-3.9; 75 patients). Finally, we found that the MYSEC-PM represents the most appropriate tool for SMF decision-making to be used in clinical and trial settings.


Asunto(s)
Policitemia Vera/genética , Policitemia Vera/mortalidad , Mielofibrosis Primaria/genética , Mielofibrosis Primaria/mortalidad , Trombocitemia Esencial/genética , Trombocitemia Esencial/mortalidad , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Mutación , Policitemia Vera/diagnóstico , Mielofibrosis Primaria/diagnóstico , Pronóstico , Factores de Riesgo , Análisis de Supervivencia , Trombocitemia Esencial/diagnóstico
9.
Leukemia ; 30(3): 666-73, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26514544

RESUMEN

Although next-generation sequencing has allowed for the detection of somatic mutations in myelodysplastic syndromes (MDS), the clinical relevance of variant allele frequency (VAF) for the majority of mutations is unknown. We profiled TP53 and 20 additional genes in our training set of 219 patients with MDS or secondary acute myeloid leukemia with findings confirmed in a validation cohort. When parsed by VAF, TP53 VAF predicted for complex cytogenetics in both the training (P=0.001) and validation set (P<0.0001). MDS patients with a TP53 VAF > 40% had a median overall survival (OS) of 124 days versus an OS that was not reached in patients with VAF <20% (hazard ratio (HR), 3.52; P=0.01) with validation in an independent cohort (HR, 4.94, P=0.01). TP53 VAF further stratified distinct prognostic groups independent of clinical prognostic scoring systems (P=0.0005). In multivariate analysis, only a TP53 VAF >40% was an independent covariate (HR, 1.61; P<0.0001). In addition, SRSF2 VAF predicted for monocytosis (P=0.003), RUNX1 VAF with thrombocytopenia (P=0.01) and SF3B1 with ringed sideroblasts (P=0.001). Together, our study indicates that VAF should be incorporated in patient management and risk stratification in MDS.


Asunto(s)
Frecuencia de los Genes , Leucemia Mieloide Aguda/diagnóstico , Mutación , Síndromes Mielodisplásicos/diagnóstico , Fenotipo , Proteína p53 Supresora de Tumor/genética , Anciano , Anciano de 80 o más Años , Alelos , Subunidad alfa 2 del Factor de Unión al Sitio Principal/genética , Análisis Citogenético , Femenino , Estudios de Seguimiento , Expresión Génica , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidad , Leucemia Mieloide Aguda/patología , Masculino , Persona de Mediana Edad , Análisis Multivariante , Síndromes Mielodisplásicos/genética , Síndromes Mielodisplásicos/mortalidad , Síndromes Mielodisplásicos/patología , Proteínas Nucleares/genética , Fosfoproteínas/genética , Pronóstico , Factores de Empalme de ARN , Ribonucleoproteína Nuclear Pequeña U2/genética , Ribonucleoproteínas/genética , Factores de Empalme Serina-Arginina , Análisis de Supervivencia
10.
Leukemia ; 30(3): 649-57, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26464171

RESUMEN

Established prognostic tools in patients with myelodysplastic syndromes (MDS) were largely derived from untreated patient cohorts. Although azanucleosides are standard therapies for higher-risk (HR)-MDS, the relative prognostic performance of existing prognostic tools among patients with HR-MDS receiving azanucleoside therapy is unknown. In the MDS Clinical Research Consortium database, we compared the prognostic utility of the International Prognostic Scoring System (IPSS), revised IPSS (IPSS-R), MD Anderson Prognostic Scoring System (MDAPSS), World Health Organization-based Prognostic Scoring System (WPSS) and the French Prognostic Scoring System (FPSS) among 632 patients who presented with HR-MDS and were treated with azanucleosides as the first-line therapy. Median follow-up from diagnosis was 15.7 months. No prognostic tool predicted the probability of achieving an objective response. Nonetheless, all five tools were associated with overall survival (OS, P=0.025 for the IPSS, P=0.011 for WPSS and P<0.001 for the other three tools). The corrected Akaike Information Criteria, which were used to compare OS with the different prognostic scoring systems as covariates (lower is better) were 4138 (MDAPSS), 4156 (FPSS), 4196 (IPSS-R), 4186 (WPSS) and 4196 (IPSS). Patients in the highest-risk groups of the prognostic tools had a median OS from diagnosis of 11-16 months and should be considered for up-front transplantation or experimental approaches.


Asunto(s)
Antineoplásicos/uso terapéutico , Azacitidina/análogos & derivados , Azacitidina/uso terapéutico , Síndromes Mielodisplásicos/diagnóstico , Síndromes Mielodisplásicos/tratamiento farmacológico , Anciano , Bases de Datos Factuales , Decitabina , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/mortalidad , Síndromes Mielodisplásicos/patología , Pronóstico , Proyectos de Investigación , Factores de Riesgo , Análisis de Supervivencia
11.
Blood Cancer J ; 5: e270, 2015 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-25555161

RESUMEN

In patients with chronic myelomonocytic leukemia (CMML), age>65 years is an adverse prognostic factor. Our objective in the current study was to examine risk factors for survival and treatment outcome in 261 'young' adults with CMML, as defined by age ⩽65 years. In multivariable analysis, lower HB (P=0.01), higher circulating blast % (P=0.002), ASXL1 (P=0.0007) and SRSF2 mutations (P=0.008) and Mayo-French cytogenetic stratification (P=0.04) negatively impacted survival. Similarly, leukemia-free survival was independently affected by higher circulating blast % (P<0.0001), higher bone marrow blast % (P=0.0007) and the presence of circulating immature myeloid cells (P=0.0002). Seventy-five (29%) patients received hypomethylating agents (HMA), with the median number of cycles being 5, and the median duration of therapy being 5 months. The over-all response rate was 40% for azacitidine and 30% for decitabine. Fifty-three (24%) patients underwent an allogeneic hematopoietic stem cell transplant (AHSCT), with a response rate of 56% and a non-relapse mortality of 19%. Survival in young adults with CMML, although higher than in older patients, is poor and even worse in the presence of ASXL1 and SRSF2 mutations. Treatment outcome was more impressive with AHSCT than with HMA and neither was influenced by ASXL1/SRSF2 mutations or karyotype.


Asunto(s)
Leucemia Mielomonocítica Crónica/tratamiento farmacológico , Leucemia Mielomonocítica Crónica/genética , Proteínas Nucleares/genética , Pronóstico , Ribonucleoproteínas/genética , Adulto , Supervivencia sin Enfermedad , Femenino , Humanos , Leucemia Mielomonocítica Crónica/epidemiología , Leucemia Mielomonocítica Crónica/patología , Masculino , Persona de Mediana Edad , Mutación , Factores de Empalme Serina-Arginina , Resultado del Tratamiento , Adulto Joven
12.
Blood Cancer J ; 5: e333, 2015 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-26230957

RESUMEN

Since its reclassification as a distinct disease entity, clinical research efforts have attempted to establish baseline characteristics and prognostic scoring systems for chronic myelomonocytic leukemia (CMML). Although existing data for baseline characteristics and CMML prognostication have been robustly developed and externally validated, these results have been limited by the small size of single-institution cohorts. We developed an international CMML data set that included 1832 cases across eight centers to establish the frequency of key clinical characteristics. Of note, we found that the majority of CMML patients were classified as World Health Organization CMML-1 and that a 7.5% bone marrow blast cut-point may discriminate prognosis with higher resolution in comparison with the existing 10%. We additionally interrogated existing CMML prognostic models and found that they are all valid and have comparable performance but are vulnerable to upstaging. Using random forest survival analysis for variable discovery, we demonstrated that the prognostic power of clinical variables alone is limited. Last, we confirmed the independent prognostic relevance of ASXL1 gene mutations and identified the novel adverse prognostic impact imparted by CBL mutations. Our data suggest that combinations of clinical and molecular information may be required to improve the accuracy of current CMML prognostication.


Asunto(s)
Leucemia Mielomonocítica Crónica/diagnóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Conjuntos de Datos como Asunto , Árboles de Decisión , Femenino , Predisposición Genética a la Enfermedad , Humanos , Cooperación Internacional , Estimación de Kaplan-Meier , Leucemia Mielomonocítica Crónica/genética , Leucemia Mielomonocítica Crónica/mortalidad , Masculino , Persona de Mediana Edad , Mutación , Pronóstico , Curva ROC , Adulto Joven
13.
Leukemia ; 27(7): 1504-10, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23531518

RESUMEN

We evaluated the prognostic relevance of several clinical and laboratory parameters in 226 Mayo Clinic patients with chronic myelomonocytic leukemia (CMML): 152 (67%) males and median age 71 years. At a median follow-up of 15 months, 166 (73%) deaths and 33 (14.5%) leukemic transformations were documented. In univariate analysis, significant risk factors for survival included anemia, thrombocytopenia, increased levels of white blood cells, absolute neutrophils, absolute monocyte count (AMC), absolute lymphocytes, peripheral blood and bone marrow blasts, and presence of circulating immature myeloid cells (IMCs). Spliceosome component (P=0.4) and ASXL1 mutations (P=0.37) had no impact survival. On multivariable analysis, increased AMC (>10 × 10(9)/l, relative risk (RR) 2.5, 95% confidence interval (CI) 1.7-3.8), presence of circulating IMC (RR 2.0, 95% CI 1.4-2.7), decreased hemoglobin (<10 g/dl, RR 1.6, 99% CI 1.2-2.2) and decreased platelet count (<100 × 10(9)/l, RR 1.4, 99% CI 1.0-1.9) remained significant. Using these four risk factors, a new prognostic model for overall (high risk, RR 4.4, 95% CI 2.9-6.7; intermediate risk, RR 2.0, 95% CI 1.4-2.9) and leukemia-free survival (high risk, RR 4.9, 95% CI 1.9-12.8; intermediate risk, RR 2.6, 95% CI 1.1-5.9) performed better than other conventional risk models and was validated in an independent cohort of 268 CMML patients.


Asunto(s)
Leucemia Mielomonocítica Crónica/genética , Leucemia Mielomonocítica Crónica/mortalidad , Proteínas Represoras/genética , Empalmosomas/genética , Adulto , Anciano , Anciano de 80 o más Años , Anemia/mortalidad , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Recuento de Linfocitos , Masculino , Persona de Mediana Edad , Modelos Estadísticos , Proteínas Nucleares/genética , Fosfoproteínas/genética , Pronóstico , Factores de Empalme de ARN , Ribonucleoproteína Nuclear Pequeña U2/genética , Ribonucleoproteínas/genética , Factores de Riesgo , Factores de Empalme Serina-Arginina , Factor de Empalme U2AF , Análisis de Supervivencia , Trombocitopenia/mortalidad , Organización Mundial de la Salud , Adulto Joven
14.
Leukemia ; 27(4): 897-906, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23072779

RESUMEN

Telomeres are specialized structures providing chromosome integrity during cellular division along with protection against premature senescence and apoptosis. Accelerated telomere attrition in patients with myelodysplastic syndrome (MDS) occurs by an undefined mechanism. Although the MDS clone originates within the myeloid compartment, T-lymphocytes display repertoire contraction and loss of naive T-cells. The replicative lifespan of T-cells is stringently regulated by telomerase activity. In MDS cases, we show that purified CD3+ T-cells have significantly shorter telomere length and reduced proliferative capacity upon stimulation compared with controls. To understand the mechanism, telomerase enzymatic activity and telomerase reverse transcriptase (hTERT), gene expression were compared in MDS cases (n=35) and healthy controls (n=42) within different T-cell compartments. Telomerase activity is greatest in naive T-cells illustrating the importance of telomere repair in homeostatic repertoire regulation. Compared with healthy controls, MDS cases had lower telomerase induction (P<0.0001) that correlated with significantly lower hTERT mRNA (P<0.0001), independent of age and disease stratification. hTERT mRNA deficiency affected naive but not memory T-cells, and telomere erosion in MDS occurred without evidence of an hTERT-promoter mutation, copy number variation or deletion. Telomerase insufficiency may undermine homeostatic control within the hematopoietic compartment and promote a change in the T-cell repertoire in MDS.


Asunto(s)
Síndromes Mielodisplásicos/inmunología , Linfocitos T/inmunología , Telomerasa/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Bromodesoxiuridina , Estudios de Casos y Controles , Proliferación Celular , Femenino , Humanos , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/enzimología , Síndromes Mielodisplásicos/genética , Telomerasa/metabolismo , Telómero , Adulto Joven
15.
Oncogene ; 32(9): 1110-20, 2013 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-22525275

RESUMEN

Allelic deletion of the RPS14 gene is a key effector of the hypoplastic anemia in patients with myelodysplastic syndrome (MDS) and chromosome 5q deletion (del(5q)). Disruption of ribosome integrity liberates free ribosomal proteins to bind to and trigger degradation of mouse double minute 2 protein (MDM2), with consequent p53 transactivation. Herein we show that p53 is overexpressed in erythroid precursors of primary bone marrow del(5q) MDS specimens accompanied by reduced cellular MDM2. More importantly, we show that lenalidomide (Len) acts to stabilize MDM2, thereby accelerating p53 degradation. Biochemical and molecular analyses showed that Len inhibits the haplodeficient protein phosphatase 2A catalytic domain alpha (PP2Acα) phosphatase resulting in hyperphosphorylation of inhibitory serine-166 and serine-186 residues on MDM2, and displaces binding of RPS14 to suppress MDM2 autoubiquitination whereas PP2Acα overexpression promotes drug resistance. Bone marrow specimens from del(5q) MDS patients resistant to Len overexpressed PP2Acα accompanied by restored accumulation of p53 in erythroid precursors. Our findings indicate that Len restores MDM2 functionality in the 5q- syndrome to overcome p53 activation in response to nucleolar stress, and therefore may warrant investigation in other disorders of ribosomal biogenesis.


Asunto(s)
Cromosomas Humanos Par 5 , Síndromes Mielodisplásicos/genética , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Talidomida/análogos & derivados , Proteína p53 Supresora de Tumor/metabolismo , Animales , Deleción Cromosómica , Humanos , Lenalidomida , Ratones , Talidomida/farmacología , Ubiquitinación
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