RESUMEN
The BCL-2 inhibitor venetoclax combined with hypomethylating agents or low-dose cytarabine represents an important new therapy for older or unfit patients with acute myeloid leukemia (AML). We analyzed 81 patients receiving these venetoclax-based combinations to identify molecular correlates of durable remission, response followed by relapse (adaptive resistance), or refractory disease (primary resistance). High response rates and durable remissions were typically associated with NPM1 or IDH2 mutations, with prolonged molecular remissions prevalent for NPM1 mutations. Primary and adaptive resistance to venetoclax-based combinations was most commonly characterized by acquisition or enrichment of clones activating signaling pathways such as FLT3 or RAS or biallelically perturbing TP53. Single-cell studies highlighted the polyclonal nature of intratumoral resistance mechanisms in some cases. Among cases that were primary refractory, we identified heterogeneous and sometimes divergent interval changes in leukemic clones within a single cycle of therapy, highlighting the dynamic and rapid occurrence of therapeutic selection in AML. In functional studies, FLT3 internal tandem duplication gain or TP53 loss conferred cross-resistance to both venetoclax and cytotoxic-based therapies. Collectively, we highlight molecular determinants of outcome with clinical relevance to patients with AML receiving venetoclax-based combination therapies.
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores de Tumor , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/genética , Factores de Edad , Anciano , Anciano de 80 o más Años , Alelos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Compuestos Bicíclicos Heterocíclicos con Puentes/administración & dosificación , Compuestos Bicíclicos Heterocíclicos con Puentes/efectos adversos , Compuestos Bicíclicos Heterocíclicos con Puentes/uso terapéutico , Biología Computacional/métodos , Resistencia a Antineoplásicos , Perfilación de la Expresión Génica , Humanos , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/mortalidad , Masculino , Persona de Mediana Edad , Mutación , Nucleofosmina , Pronóstico , Retratamiento , Sulfonamidas/administración & dosificación , Sulfonamidas/efectos adversos , Sulfonamidas/uso terapéutico , Insuficiencia del Tratamiento , Resultado del TratamientoRESUMEN
The apoptosis repressor with caspase recruitment domain (ARC) protein is known to suppress both intrinsic and extrinsic apoptosis. We previously reported that ARC expression is a strong, independent adverse prognostic factor in acute myeloid leukemia (AML). Here, we investigated the regulation and role of ARC in AML. ARC expression is upregulated in AML cells co-cultured with bone marrow-derived mesenchymal stromal cells (MSCs) and suppressed by inhibition of MAPK and PI3K signaling. AML patient samples with RAS mutations (N = 64) expressed significantly higher levels of ARC than samples without RAS mutations (N = 371) (P = 0.016). ARC overexpression protected and ARC knockdown sensitized AML cells to cytarabine and to agents that selectively induce intrinsic (ABT-737) or extrinsic (TNF-related apoptosis inducing ligand) apoptosis. NOD-SCID mice harboring ARC-overexpressing KG-1 cells had significantly shorter survival than mice injected with control cells (median 84 vs 111 days) and significantly fewer leukemia cells were present when NOD/SCID IL2Rγ null mice were injected with ARC knockdown as compared to control Molm13 cells (P = 0.005 and 0.03 at 2 and 3 weeks, respectively). Together, these findings demonstrate that MSCs regulate ARC in AML through activation of MAPK and PI3K signaling pathways. ARC confers drug resistance and survival advantage to AML in vitro and in vivo, suggesting ARC as a novel target in AML therapy.
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Caspasas/metabolismo , Proteínas del Citoesqueleto/metabolismo , Leucemia Mieloide Aguda/metabolismo , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Animales , Antimetabolitos Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular , Supervivencia Celular , Citarabina/farmacología , Resistencia a Antineoplásicos , Humanos , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/patología , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Ratones , Ratones Endogámicos NOD , Ratones SCID , Trasplante de Neoplasias , Transducción de SeñalRESUMEN
Homoharringtonine is an alkaloid inhibitor of protein synthesis with activity in myeloid malignancies. We report a phase II pilot study of homoharringtonine in myelodysplastic syndrome (MDS). Induction consisted of homoharringtonine at 2.5 mg/m(2) via continuous infusion for 7 days. Maintenance was given every 4 weeks. Nine patients were enrolled: five with refractory anaemia with excess blasts, two with refractory anaemia with excess blasts in transformation, one each with refractory anaemia and chronic myelomonocytic leukaemia respectively. Median age was 70 years (55-84) and 6 (66%) were male. Per International Prognostic Scoring System (IPSS) two patients were intermediate-1, five intermediate-2 and two high-risk. Median chemotherapy courses were one (1-3). One patient (11%) responded with complete haematological and cytogenetic remission after one course. Eight patients did not respond (four had stable disease, two progressed to acute leukaemia and two died during induction - from aspergillus pneumonia and intracerebral haemorrhage respectively). Grade 3/4 myelosuppression seen in 56% (5/9). Serious non-haematological toxicities included one case of grade 4 left bundle branch heart block and one grade 3 nephrotoxicity. Median time between courses was 42 days (35-72 days). In conclusion homoharringtonine might have clinical activity in some patients with MDS.
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Harringtoninas/administración & dosificación , Hematínicos/administración & dosificación , Síndromes Mielodisplásicos/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Esquema de Medicación , Femenino , Harringtoninas/efectos adversos , Hematínicos/efectos adversos , Homoharringtonina , Humanos , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Proyectos Piloto , Resultado del TratamientoRESUMEN
BACKGROUND: Acute leukemia is an epigenetically heterogeneous disease. The intensity of treatment is currently guided by cytogenetic and molecular genetic risk classifications; however these incompletely predict outcomes, requiring additional information for more accurate outcome predictions. We aimed to identify potential prognostic implications of epigenetic modification of histone proteins, with a focus on H3K4 and H3K27 methylation marks in relation to mutations in chromatin, splicing and transcriptional regulators in adult-onset acute lymphoblastic and myeloid leukemia. RESULTS: Histone 3 lysine 4 di- and trimethylation (H3K4me2, H3K4me3) and lysine 27 trimethylation (H3K27me3) mark expression was evaluated in 241 acute myeloid leukemia (AML), 114 B-cell acute lymphoblastic leukemia (B-ALL) and 14T-cell ALL (T-ALL) patient samples at time of diagnosis using reverse phase protein array. Expression levels of the marks were significantly lower in AML than in B and T-ALL in both bone marrow and peripheral blood, as well as compared to normal CD34+ cells. In AML, greater loss of H3K27me3 was associated with increased proliferative potential and shorter overall survival in the whole patient population, as well as in subsets with DNA methylation mutations. To study the prognostic impact of H3K27me3 in the context of cytogenetic aberrations and mutations, multivariate analysis was performed and identified lower H3K27me3 level as an independent unfavorable prognostic factor in all, as well as in TP53 mutated patients. AML with decreased H3K27me3 demonstrated an upregulated anti-apoptotic phenotype. In ALL, the relative quantity of histone methylation expression correlated with response to tyrosine kinase inhibitor in patients who carried the Philadelphia cytogenetic aberration and prior smoking behavior. CONCLUSION: This study shows that proteomic profiling of epigenetic modifications has clinical implications in acute leukemia and supports the idea that epigenetic patterns contribute to a more accurate picture of the leukemic state that complements cytogenetic and molecular genetic subgrouping. A combination of these variables may offer more accurate outcome prediction and we suggest that histone methylation mark measurement at time of diagnosis might be a suitable method to improve patient outcome prediction and subsequent treatment intensity stratification in selected subgroups.
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Histonas/metabolismo , Leucemia Mieloide Aguda/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Edad de Inicio , Anciano , Antígenos CD34/metabolismo , Estudios de Casos y Controles , Aberraciones Cromosómicas/estadística & datos numéricos , Metilación de ADN , Epigenómica , Femenino , Regulación Leucémica de la Expresión Génica/genética , Código de Histonas/genética , Histonas/genética , Humanos , Histona Demetilasas con Dominio de Jumonji/genética , Leucemia Mieloide Aguda/sangre , Leucemia Mieloide Aguda/patología , Masculino , Persona de Mediana Edad , Mutación , Leucemia-Linfoma Linfoblástico de Células Precursoras/sangre , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Pronóstico , Análisis por Matrices de Proteínas/métodos , Proteómica , Tasa de Supervivencia , Factores de Transcripción/genéticaRESUMEN
Acute myelogenous leukaemia (AML) is associated with risk factors that are largely unknown and with a heterogeneous response to treatment. Here, we provide a comprehensive quantitative understanding of AML proteomic heterogeneities and hallmarks by using the AML Proteome Atlas, a proteomics database that we have newly derived from MetaGalaxy analyses, for the proteomic profiling of 205 patients with AML and 111 leukaemia cell lines. The analysis of the dataset revealed 154 functional patterns based on common molecular pathways, 11 constellations of correlated functional patterns and 13 signatures that stratify the outcomes of patients. We find limited overlap between proteomics data and both cytogenetics and genetic mutations. Moreover, leukaemia cell lines show limited proteomic similarities with cells from patients with AML, suggesting that a deeper focus on patient-derived samples is needed to gain disease-relevant insights. The AML Proteome Atlas provides a knowledge base for proteomic patterns in AML, a guide to leukaemia cell line selection, and a broadly applicable computational approach for quantifying the heterogeneities of protein expression and proteomic hallmarks in AML.
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Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Proteoma/genética , Proteoma/metabolismo , Proteómica , Línea Celular Tumoral , Bases de Datos Factuales , Humanos , Leucemia , Mutación , Proteínas de Neoplasias/análisis , Pronóstico , Modelos de Riesgos Proporcionales , Análisis de Regresión , Factores de Riesgo , TranscriptomaRESUMEN
The mitogen-activated protein kinase (MAPK) pathway regulates growth and survival of many cell types, and its constitutive activation has been implicated in the pathogenesis of a variety of malignancies. In this study we demonstrate that small-molecule MEK inhibitors (PD98059 and PD184352) profoundly impair cell growth and survival of acute myeloid leukemia (AML) cell lines and primary samples with constitutive MAPK activation. These agents abrogate the clonogenicity of leukemic cells but have minimal effects on normal hematopoietic progenitors. MEK blockade also results in sensitization to spontaneous and drug-induced apoptosis. At a molecular level, these effects correlate with modulation of the expression of cyclin-dependent kinase inhibitors (p27(Kip1) and p21(Waf1/CIP1)) and antiapoptotic proteins of the inhibitor of apoptosis proteins (IAP) and Bcl-2 families. Interruption of constitutive MEK/MAPK signaling therefore represents a promising therapeutic strategy in AML.
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Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/enzimología , Quinasas de Proteína Quinasa Activadas por Mitógenos/antagonistas & inhibidores , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Proteínas Supresoras de Tumor , Apoptosis/efectos de los fármacos , Benzamidas/farmacología , Ciclo Celular/efectos de los fármacos , Proteínas de Ciclo Celular/genética , División Celular/efectos de los fármacos , Inhibidor p21 de las Quinasas Dependientes de la Ciclina , Inhibidor p27 de las Quinasas Dependientes de la Ciclina , Ciclinas/genética , Citarabina/farmacología , Inhibidores Enzimáticos/farmacología , Flavonoides/farmacología , Humanos , Leucemia Mieloide Aguda/patología , Proteínas/genética , Proteínas Proto-Oncogénicas c-bcl-2/genética , Transducción de Señal , Células Tumorales Cultivadas , Proteína Inhibidora de la Apoptosis Ligada a XRESUMEN
We analyzed the clinical factors associated with late cytomegalovirus (CMV) reactivation in a group of 269 consecutive recipients of allogeneic stem cell transplant (SCT) for hematological malignancies. Eighty-four subjects (31%) experienced late CMV reactivation, including 64 with prior early reactivation and 20 with isolated late reactivation. Multivariate analyses were conducted in patients with early CMV reactivation to identify factors associated with late recurrence. Important risk factors included lymphoid diagnosis, occurrence of graft-versus-host disease (GVHD), greater number of episodes of early reactivation, persistent day 100 lymphopenia and the use of a CMV-seronegative donor graft. We combined these risk factors in a predictive model to identify those at relatively low, intermediate and high risk. The low-risk group (15% cumulative incidence, CI) encompassed patients without early CMV reactivation, and subjects transplanted for a myeloid malignancy from a matched-related (MR) donor without subsequent acute GVHD. The high-risk patients (73% CI) met all of the following criteria: (1) received an MR graft but developed GVHD, or received a non-MR graft irrespective of GVHD; (2) had more than two episodes of early reactivation; and (3) received a CMV-seronegative graft and/or remained persistently lymphopenic at day 100 after SCT. The remaining patients had an intermediate incidence of 32%.
Asunto(s)
Infecciones por Citomegalovirus/etiología , Neoplasias Hematológicas/terapia , Trasplante de Células Madre/efectos adversos , Adolescente , Adulto , Anciano , Femenino , Enfermedad Injerto contra Huésped/etiología , Neoplasias Hematológicas/inmunología , Prueba de Histocompatibilidad , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Recurrencia , Factores de Riesgo , Linfocitos T/inmunología , Factores de Tiempo , Trasplante HomólogoRESUMEN
TP53 mutations are associated with the lowest survival rates in acute myeloid leukemia (AML). In addition to mutations, loss of p53 function can arise via aberrant expression of proteins that regulate p53 stability and function. We examined a large AML cohort using proteomics, mutational profiling and network analyses, and showed that (1) p53 stabilization is universal in mutant TP53 samples, it is frequent in samples with wild-type TP53, and in both cases portends an equally dismal prognosis; (2) the p53 negative regulator Mdm2 is frequently overexpressed in samples retaining wild-type TP53 alleles, coupled with absence of p21 expression and dismal prognosis similar to that of cases with p53 stabilization; (3) AML samples display unique patterns of p53 pathway protein expression, which segregate prognostic groups with distinct cure rates; (4) such patterns of protein activation unveil potential AML vulnerabilities that can be therapeutically exploited.
Asunto(s)
Biomarcadores de Tumor/metabolismo , Leucemia Mieloide Aguda/patología , Mutación , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Anciano , Biomarcadores de Tumor/genética , Femenino , Estudios de Seguimiento , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Fosforilación , Pronóstico , Análisis por Matrices de Proteínas , Procesamiento Proteico-Postraduccional , Estabilidad Proteica , Proteínas Proto-Oncogénicas c-mdm2/genética , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Tasa de Supervivencia , Proteína p53 Supresora de Tumor/químicaRESUMEN
Cancer metabolism differs remarkably from the metabolism of healthy surrounding tissues, and it is extremely heterogeneous across cancer types. While these metabolic differences provide promising avenues for cancer treatments, much work remains to be done in understanding how metabolism is rewired in malignant tissues. To that end, constraint-based models provide a powerful computational tool for the study of metabolism at the genome scale. To generate meaningful predictions, however, these generalized human models must first be tailored for specific cell or tissue sub-types. Here we first present two improved algorithms for (1) the generation of these context-specific metabolic models based on omics data, and (2) Monte-Carlo sampling of the metabolic model ux space. By applying these methods to generate and analyze context-specific metabolic models of diverse solid cancer cell line data, and primary leukemia pediatric patient biopsies, we demonstrate how the methodology presented in this study can generate insights into the rewiring differences across solid tumors and blood cancers.
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Modelos Biológicos , Neoplasias/metabolismo , Algoritmos , Línea Celular Tumoral , Niño , Biología Computacional , Humanos , Leucemia/metabolismo , Redes y Vías Metabólicas , Método de Montecarlo , Neoplasias/genética , ProteómicaRESUMEN
Genetic changes are infrequent in acute myeloid leukemia (AML) compared with other malignancies and often involve epigenetic regulators, suggesting that an altered epigenome may underlie AML biology and outcomes. In 96 AML cases including 65 pilot samples selected for cured/not-cured, we found higher CpG island (CGI) promoter methylation in cured patients. Expanded genome-wide digital restriction enzyme analysis of methylation data revealed a CGI methylator phenotype independent of IDH1/2 mutations we term AML-CGI methylator phenotype (CIMP) (A-CIMP+). A-CIMP was associated with longer overall survival (OS) in this data set (median OS, years: A-CIMP+=not reached, CIMP-=1.17; P=0.08). For validation we used 194 samples from The Cancer Genome Atlas interrogated with Illumina 450k methylation arrays where we confirmed longer OS in A-CIMP (median OS, years: A-CIMP+=2.34, A-CIMP-=1.00; P=0.01). Hypermethylation in A-CIMP+ favored CGIs (OR: CGI/non-CGI=5.21), and while A-CIMP+ was enriched in CEBPA (P=0.002) and WT1 mutations (P=0.02), 70% of cases lacked either mutation. Hypermethylated genes in A-CIMP+ function in pluripotency maintenance, and a gene expression signature of A-CIMP was associated with outcomes in multiple data sets. We conclude that CIMP in AML cannot be explained solely by gene mutations (for example, IDH1/2, TET2), and that curability in A-CIMP+ AML should be validated prospectively.
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Islas de CpG , Metilación de ADN , Leucemia Mieloide Aguda/genética , Adolescente , Adulto , Anciano , ADN de Neoplasias/genética , Conjuntos de Datos como Asunto , Femenino , Humanos , Isocitrato Deshidrogenasa/genética , Leucemia Mieloide Aguda/mortalidad , Masculino , Persona de Mediana Edad , Mutación , Fenotipo , Proyectos Piloto , Pronóstico , Estudios Retrospectivos , Riesgo , Análisis de Supervivencia , Adulto JovenRESUMEN
Partial tandem duplication of MLL (MLL-PTD) characterizes acute myeloid leukemia (AML) patients often with a poor prognosis. To understand the order of occurrence of MLL-PTD in relation to other major AML mutations and to identify novel mutations that may be present in this unique AML molecular subtype, exome and targeted sequencing was performed on 85 MLL-PTD AML samples using HiSeq-2000. Genes involved in the cohesin complex (STAG2), a splicing factor (U2AF1) and a poorly studied gene, MGA were recurrently mutated, whereas NPM1, one of the most frequently mutated AML gene, was not mutated in MLL-PTD patients. Interestingly, clonality analysis suggests that IDH2/1, DNMT3A, U2AF1 and TET2 mutations are clonal and occur early, and MLL-PTD likely arises after these initial mutations. Conversely, proliferative mutations (FLT3, RAS), typically appear later, are largely subclonal and tend to be unstable. This study provides important insights for understanding the relative importance of different mutations for defining a targeted therapeutic strategy for MLL-PTD AML patients.
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N-Metiltransferasa de Histona-Lisina/genética , Leucemia Mieloide Aguda/genética , Mutación , Proteína de la Leucemia Mieloide-Linfoide/genética , Proliferación Celular/genética , Células Clonales , Exoma , Humanos , Tasa de Mutación , Nucleofosmina , Secuencias Repetidas en Tándem , Factores de TiempoAsunto(s)
Genes Virales , Marcadores Genéticos , Vectores Genéticos/efectos adversos , Receptor de Factor de Crecimiento Nervioso/análisis , Retroviridae/genética , Animales , Trasplante de Médula Ósea , Perros , Humanos , Leucemia/etiología , Leucemia/prevención & control , Ratones , Ratas , Transducción GenéticaRESUMEN
Numerous studies have analyzed the expression and prognostic importance of various proteins in acute myelogenous leukemia (AML). We sought to determine whether the sample source and methodology used to measure protein expression affect the results obtained. To determine the importance of sample source, we used Western blotting to compare the expression of eight proteins and phosphoproteins in the leukemia blast-enriched fraction of 118 blood- and 108 marrow-derived samples, including 37 paired samples. To determine the importance of methodology, the expression of five proteins was measured in 20 paired samples by Western blotting, laser scanning cytometry (LSC), and flow cytometry. The mean expression and range of expression in blood- and marrow-derived samples were statistically identical for all eight proteins. Expression measurements for the 37 paired blood and marrow samples also had very high statistical correlation. The LSC and flow cytometry data had the highest concordance when compared using Kolmogorov-Smirnoff D-stats (range of R values, 0.8-1.0). High concordance was also observed between the LSC and flow cytometry results when the percentage of cells positive for expression was dichotomized into positive or negative expression. However, there was less correlation between LSC and flow cytometry when the actual percentages of positive cells were compared. The majority of discordant situations involved samples that were positive by flow cytometry but negative by LSC. The correlation between Western blotting signal intensity and the percentage of expression-positive cells measured by LSC or flow cytometry varied by protein but was limited when there was little heterogeneity in expression by either method. In conclusion, provided that leukemia blast-enriched fractions were analyzed, the blood- and marrow-derived samples had identical protein expression. There was good concordance of results between flow cytometry and LSC, which share similar technology, but more limited correlation between these methods and Western blotting.
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Western Blotting/métodos , Citometría de Flujo/métodos , Citometría de Barrido por Láser/métodos , Leucemia Mieloide Aguda/metabolismo , Proteínas/análisis , Proteínas/metabolismo , Humanos , Fosfoproteínas/análisis , Fosfoproteínas/metabolismo , FosforilaciónRESUMEN
Suicidal lymphocytes could greatly expand the role of allogeneic transplantation by reducing graft-versus-host disease (GVHD) as a barrier to transplantation, but optimization of their use is hindered by the lack of adequate animal models. To develop an animal model that used retrovirally transduced suicidal lymphocytes in a GVHD setting, a well-characterized MHC-matched murine transplant model (B10.BR-->AKR/J) was adapted. B10.BR splenic lymphocytes stimulated with concanavalin A and interleukin 2 were infected with a retrovirus containing the low-affinity nerve growth factor receptor (LNGFR) and the HSV-TK gene and immunomagnetically selected; these LNGFR+/TK+ allogeneic lymphocytes were then cotransplanted with 1 x 10(7) bone marrow cells into lethally irradiated AKR/J recipients. The LNGFR+/TK+ donor lymphocytes persisted in the peripheral circulation for 6 months in both syngeneic and allogeneic settings. Doses of 2 x 10(6) TK+ allogeneic lymphocytes produced GVHD with a severity and time course similar to that induced by naive lymphocytes. Survival of TK+ allogeneic lymphocyte-bearing mice was significantly improved (P = 0.01) when ganciclovir (GCV; 2 mg/day) was administered on days 7-13 post transplant by i.p. injection, demonstrating that GVHD could be prevented. Fluorescence-activated cell sorting analysis demonstrated 4-fold reduction but persistent circulation of LNGFR+ lymphocytes in mice treated with GCV at various time points 1-3 months after transplantation, demonstrating selective killing of GVHD-reactive cells. We conclude that retrovirally transduced LNGFR+/TK+ murine lymphocytes can be produced, persist after transplant, remain alloreactive, and can be killed by GCV administration, resulting in reduced GVHD.
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Trasplante de Médula Ósea/inmunología , Enfermedad Injerto contra Huésped/prevención & control , Linfocitos T/fisiología , Linfocitos T/trasplante , Animales , Muerte Celular , División Celular/fisiología , Supervivencia Celular/fisiología , Modelos Animales de Enfermedad , Ganciclovir/farmacocinética , Ganciclovir/farmacología , Enfermedad Injerto contra Huésped/inmunología , Ratones , Ratones Endogámicos AKR , Receptor de Factor de Crecimiento Nervioso/genética , Retroviridae/genética , Simplexvirus/enzimología , Simplexvirus/genética , Linfocitos T/inmunología , Timidina Quinasa/genética , Transducción Genética , Quimera por TrasplanteRESUMEN
The detection of abnormalities at the retinoblastoma (RB) locus by cytogenetics, Southern blot, and fluorescence in situ hybridization studies suggests that the RB gene has a role in chronic lymphocytic leukemia (CLL). To further study this role, we determined the level of RB protein present in the mononuclear cell fraction derived from peripheral blood or bone marrow samples from 74 patients with CLL, by Western blotting. Compared to similarly prepared samples from the peripheral blood of normal individuals, the level of RB in CLL cells was less than normal in 42% of patients, equal to normal in 22% of patients, and in excess of normal in 36% of patients. Regardless of whether the source of the sample was blood or marrow or if the patients were untreated or previously treated, similar rates of low, normal, and elevated RB levels were observed. RB protein in the CLL patient samples was never phosphorylated. RB levels showed no correlation with the lymphocyte doubling time or with proliferating cell nuclear antigen levels. Low RB levels could arise from genetic alterations of the RB gene or altered regulation of expression. To determine which was occurring, we stimulated the cells from 27 CLL patients in culture with either phytohemagglutinin or pokeweed mitogen in an attempt to induce RB expression and phosphorylation. Among patients with low levels of RB, expression was induced in 46% (6 of 13), and phosphorylation of RB was seen in 31% (4 of 13). Increased expression of phosphorylated RB was induced in 80% (4 of 5) of patients with normal levels of RB and in 78% (7 of 9) of patients with high levels of RB. This study demonstrates that absent RB expression occurs commonly in patients with CLL. Intrinsic abnormalities of the RB gene may be present in those patients with low levels of RB that could not be stimulated by mitogens, while regulatory abnormalities located in trans to the RB gene may occur in the other half. Given the importance that RB levels play in other cancers, the prognostic implication of low RB levels should be studied in CLL.
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Médula Ósea/química , Leucemia Linfocítica Crónica de Células B , Proteína de Retinoblastoma/análisis , Western Blotting , Femenino , Humanos , Leucemia Linfocítica Crónica de Células B/sangre , Linfocitos/química , Masculino , Persona de Mediana EdadRESUMEN
The retinoblastoma (RB) protein levels in blast-enriched mononuclear fractions from the peripheral blood of 33 newly diagnosed patients with acute myelogenous leukemia were studied. Ten patients who had previously been treated were also analyzed, nine of whom had achieved prior complete remission. Low RB protein expression was found in 13 of 43 (30%) of the acute myelogenous leukemia patients as determined by Western blotting and immunochemical analysis. Of particular interest among the 20 newly diagnosed patients treated with the same therapeutic regimen, the median survival was 39 days for those with low RB protein expression compared to 333 days for those with high levels of RB protein expression in their leukemic cells (P less than or equal to 0.02). This preliminary study suggests that decreases of RB protein expression in peripheral blood of myeloid leukemic cells occur frequently and may be associated with shortened survival of acute myelogenous leukemia patients.
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Leucemia Mieloide Aguda/metabolismo , Proteína de Retinoblastoma/metabolismo , Western Blotting , Humanos , Pronóstico , Análisis de SupervivenciaRESUMEN
Acute promyelocytic leukemia (APL) is a subtype of myeloid leukemia characterized by differentiation block at the promyelocyte stage. Besides the presence of chromosomal rearrangement t(15;17), leading to the formation of PML-RARA (promyelocytic leukemia-retinoic acid receptor alpha) fusion, other genetic alterations have also been implicated in APL. Here, we performed comprehensive mutational analysis of primary and relapse APL to identify somatic alterations, which cooperate with PML-RARA in the pathogenesis of APL. We explored the mutational landscape using whole-exome (n=12) and subsequent targeted sequencing of 398 genes in 153 primary and 69 relapse APL. Both primary and relapse APL harbored an average of eight non-silent somatic mutations per exome. We observed recurrent alterations of FLT3, WT1, NRAS and KRAS in the newly diagnosed APL, whereas mutations in other genes commonly mutated in myeloid leukemia were rarely detected. The molecular signature of APL relapse was characterized by emergence of frequent mutations in PML and RARA genes. Our sequencing data also demonstrates incidence of loss-of-function mutations in previously unidentified genes, ARID1B and ARID1A, both of which encode for key components of the SWI/SNF complex. We show that knockdown of ARID1B in APL cell line, NB4, results in large-scale activation of gene expression and reduced in vitro differentiation potential.
Asunto(s)
Análisis Mutacional de ADN/métodos , Leucemia Promielocítica Aguda/genética , Diferenciación Celular , Proteínas de Unión al ADN/genética , Exoma/genética , Perfilación de la Expresión Génica , Humanos , Proteínas Nucleares/genética , Recurrencia , Factores de Transcripción/genéticaRESUMEN
PURPOSE: To determine whether granulocyte colony-stimulating factor (G-CSF) administered before, during, and after fludarabine plus cytarabine (ara-C; FA) chemotherapy affected complete response (CR) rate, infection rate, blood count recovery, or survival in patients with newly diagnosed acute myelogenous leukemia (AML) or myelodysplastic syndromes (MDS). PATIENTS AND METHODS: A total of 112 patients with newly diagnosed AML (n = 69) or MDS (n = 43) received G-CSF 400 micrograms/m2/d 1 day before (presenting WBC count < 50,000/microL) and/or during (all patients) fludarabine 30 mg/m2/d and ara-C 2 g/m2/d for 5 days (FLAG). G-CSF continued until a CR was achieved. Results were compared with those in 85 newly diagnosed patients (54 AML, 31 MDS) previously treated with FA without G-CSF. RESULTS: Patients in both groups were relatively old (median age of all patients, 63 years), and were likely to have prognostically unfavorable cytogenetic abnormalities (36% had abnormalities of chromosomes 5 and 7 [-5/-7]). G-CSF accelerated recovery to > or = 1,000 neutrophils (P < .0001; median, 34 days for FA, 21 days for FLAG), but logistic regression provided no evidence that the CR rate was higher with FLAG than with FA (P = .50), with unadjusted CR rates of 63% and 53%, respectively. This may reflect relatively high rates of death before neutrophil recovery in both groups. Rates of infection were similar in both groups. The follow-up duration in remission is short, and much of these data remain censored. To date, survival is similar with FA and FLAG. CONCLUSION: On average, G-CSF before, during, and after FA had no effect on CR or infection rates in this population, in which elderly patients and poor prognostic factors were prevalent. The use of FA and laminar airflow rooms rather than more usual therapy needs to be considered when analyzing the results.
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Enfermedades de la Médula Ósea/tratamiento farmacológico , Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Leucemia Mieloide Aguda/tratamiento farmacológico , Síndromes Mielodisplásicos/tratamiento farmacológico , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Enfermedades de la Médula Ósea/inducido químicamente , Citarabina/efectos adversos , Esquema de Medicación , Femenino , Humanos , Incidencia , Infecciones/epidemiología , Masculino , Persona de Mediana Edad , Neutrófilos/efectos de los fármacos , Análisis de Regresión , Inducción de Remisión , Análisis de Supervivencia , Resultado del Tratamiento , Vidarabina/efectos adversos , Vidarabina/análogos & derivadosRESUMEN
PURPOSE: To estimate the incidence of idarubicin (IDA)-related cardiomyopathy in acute myeloid leukemia (AML) and myelodysplasia (MDS). PATIENTS AND METHODS: We analyzed a group of 127 AML/MDS patients who received IDA-based induction and postremission or salvage therapy and achieved a complete remission (CR) that lasted > or = 12 weeks for the development of IDA-related congestive heart failure (CHF). CHF was defined as definite if a resting left ventricular ejection fraction (LVEF) of < or = 45% measured by radionuclide ventriculogram (RV) accompanied the clinical diagnosis of CHF, which had to be made during or within 6 months of receiving IDA and for which no other cause was apparent; without RV confirmation, the diagnosis was considered probable. Patients who had RVs performed were evaluated for decreasing LVEF. Older age (> or = 70 years), prior/sequential anthracycline/mitoxantrone (anthraquinone) therapy, and cardiac disease/hypertension were evaluated as risk factors for the development of CHF. RESULTS: One hundred fifteen patients were assessable (median age, 40 years; median dose, 96 mg/m2). Sixty-five had RVs performed during therapy; 43 had risk factors. The probability of IDA-related cardiomyopathy was 5% at a cumulative IDA dose of 150 to 290 mg/m2, with 18 patients receiving doses greater than 150 mg/m2. At a cumulative IDA dose of 150 mg/m2, the probability of a mild or greater asymptomatic decrease probability of a mild or greater asymptomatic decrease in LVEF (> or = 10% to a level < or = 50%) was 18%, whereas the probability of a moderate or greater asymptomatic decrease in LVEF (> or = 15% to a level < or = 45%) was 7%. No patient with asymptomatic LVEF decreases developed CHF. CHF was more frequent in patients with prior/sequential exposure to anthracyclines/mitoxantrone (P = .01). CONCLUSION: In this patient group, IDA-related cardiomyopathy was uncommon with cumulative IDA doses of up to 290 mg/m2. Asymptomatic LVEF decreases were more frequent, but their predictive value for the development of CHF is unclear.
Asunto(s)
Antibióticos Antineoplásicos/efectos adversos , Insuficiencia Cardíaca/inducido químicamente , Corazón/efectos de los fármacos , Idarrubicina/efectos adversos , Leucemia Mieloide Aguda/tratamiento farmacológico , Síndromes Mielodisplásicos/tratamiento farmacológico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antibióticos Antineoplásicos/administración & dosificación , Femenino , Corazón/fisiopatología , Insuficiencia Cardíaca/fisiopatología , Humanos , Idarrubicina/administración & dosificación , Masculino , Persona de Mediana Edad , Inducción de Remisión , Estudios Retrospectivos , Factores de Riesgo , Volumen Sistólico/efectos de los fármacosRESUMEN
PURPOSE: Management of chemotherapy-induced diarrhea (CID) has customarily involved symptomatic treatment with opioids in conjunction with supportive care. Alternatively, patients refractory to conventional therapy have been given octreotide, a somatostatin analogue. Although this agent has been effective against CID, no widely accepted treatment guidelines that incorporate its use currently exist. An expert multidisciplinary panel was convened to formulate clinical practice guidelines for the treatment of CID. METHODS: The panel reviewed clinical data on the management of CID reported in the literature and analyzed currently available tools used to assess CID. Expert consensus was applied when published data were insufficient. Panel members also considered the effect of CID on quality of life and the cost-effectiveness and efficacy of different pharmacologic approaches. Effective resolution of CID and decreases in the need for supportive care or hospitalization were considered to be primary goals in the formulation of the guidelines. RESULTS: The panel formulated suggested practice guidelines for the management of CID that detail recommendations for the assessment and evaluation of diarrhea and the sequence and duration of administration of specific pharmacologic agents. CONCLUSION: The consensus of the panel was that standardized assessment and management of diarrhea is required to effectively control CID. The panel agreed that further data from a National Cancer Institute (NCI)-sponsored intergroup trial is required to determine the optimal dosage of octreotide and its cost in the treatment of cancer. The panel also agreed that further clinical research is warranted to address significant questions about the most effective way to assess and treat CID.