RESUMEN
Dendrogenin A (DDA) is a newly discovered cholesterol metabolite with tumor suppressor properties. Here, we explored its efficacy and mechanism of cell death in melanoma and acute myeloid leukemia (AML). We found that DDA induced lethal autophagy in vitro and in vivo, including primary AML patient samples, independently of melanoma Braf status or AML molecular and cytogenetic classifications. DDA is a partial agonist on liver-X-receptor (LXR) increasing Nur77, Nor1, and LC3 expression leading to autolysosome formation. Moreover, DDA inhibited the cholesterol biosynthesizing enzyme 3ß-hydroxysterol-Δ8,7-isomerase (D8D7I) leading to sterol accumulation and cooperating in autophagy induction. This mechanism of death was not observed with other LXR ligands or D8D7I inhibitors establishing DDA selectivity. The potent anti-tumor activity of DDA, its original mechanism of action and its low toxicity support its clinical evaluation. More generally, this study reveals that DDA can direct control a nuclear receptor to trigger lethal autophagy in cancers.
Asunto(s)
Antineoplásicos/farmacología , Autofagia/efectos de los fármacos , Colestanoles/farmacología , Imidazoles/farmacología , Leucemia Mieloide Aguda , Receptores X del Hígado/efectos de los fármacos , Melanoma , Animales , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Agonismo Parcial de Drogas , Expresión Génica/efectos de los fármacos , Células HEK293 , Células HL-60 , Humanos , Técnicas In Vitro , Receptores X del Hígado/metabolismo , Melanoma Experimental , Proteínas de Transporte de Membrana/efectos de los fármacos , Proteínas de Transporte de Membrana/genética , Ratones , Proteínas Asociadas a Microtúbulos/efectos de los fármacos , Proteínas Asociadas a Microtúbulos/genética , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares/efectos de los fármacos , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares/genéticaRESUMEN
Long non-coding RNAs are defined as transcripts larger than 200 nucleotides but without protein-coding potential. There is growing evidence of the important role of long non-coding RNAs in cancer initiation, development and progression. In this study, we sought to evaluate the long non-coding RNA expression profile of patients with cytogenetically normal acute myeloid leukemia (AML). RNA-sequencing of 40 cytogenetically normal AML patients allowed us to quantify 11,036 long non-coding RNAs. Among these, more than 8000 were previously undescribed long non-coding RNAs. Using unsupervised analysis, we observed a specific long non-coding RNA expression profile dependent on the mutational status of the NPM1 gene. Statistical analysis allowed us to identify a minimal set of 12 long non-coding RNAs capable of discriminating NPM1-mutated from NPM1-wild-type patients. These results were validated by qRT-PCR on an independent cohort composed of 134 cytogenetically normal AML patients. Furthermore, we have identified one putative biomarker, the long non-coding RNA XLOC_109948 whose expression pattern predicts clinical outcome. Interestingly, low XLOC_109948 expression indicates a good prognosis especially for NPM1-mutated patients. Transient transfection of GapmeR against XLOC_109948 in NPM1-mutated OCI-AML3 cell line treated with Ara-C or ATRA enhances apoptosis suggesting XLOC_109948 plays a role in drug sensitivity. This study improves our knowledge of the long non-coding RNA transcriptome in cytogenetically normal AML patients. We observed a distinct long non-coding RNA expression profile in patients with the NPM1 mutation. The newly identified XLOC_109948 long non-coding RNA emerged as a strong prognostic factor able to better stratify NPM1-mutated patients.
Asunto(s)
Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Mutación , Proteínas Nucleares/genética , ARN Largo no Codificante/genética , Transcriptoma , Apoptosis/genética , Biomarcadores , Línea Celular Tumoral , Análisis por Conglomerados , Perfilación de la Expresión Génica , Regulación Leucémica de la Expresión Génica , Humanos , Cariotipo , Leucemia Mieloide Aguda/mortalidad , Nucleofosmina , Pronóstico , Análisis de Secuencia de ARNRESUMEN
Optimal treatment of blastic plasmacytoid dendritic cell neoplasm (BPDCN), a rare entity of dismal prognosis previously described as CD4+/CD56+ hematodermic malignancies, is not defined. We report five cases of relapsed BPDCN treated with bendamustine hydrochloride, a well-tolerated bifunctional drug acting as an alkylating and antimetabolite agent. All patients were above the age of 50 years and in advanced disease (early first relapse in two, subsequent relapse in three; multi-organ involvement in four; previous intensive chemotherapy in five; and stem cell transplantation in four). Four patients were evaluable for response. Two failed therapy, one died from tumor lysis syndrome after rapid blast clearance from blood, and one reached and maintained complete remission for 7 months. Bendamustine should be further evaluated in BPDCN. Copyright © 2015 John Wiley & Sons, Ltd.
Asunto(s)
Antineoplásicos Alquilantes/uso terapéutico , Clorhidrato de Bendamustina/uso terapéutico , Células Dendríticas/patología , Neoplasias Hematológicas/tratamiento farmacológico , Anciano , Crisis Blástica , Neoplasias Hematológicas/patología , Humanos , Masculino , Persona de Mediana Edad , RecurrenciaRESUMEN
We investigated cell cycle regulation in acute myeloid leukemia cells expressing the FLT3-ITD mutated tyrosine kinase receptor, an underexplored field in this disease. Upon FLT3 inhibition, CDC25A mRNA and protein were rapidly down-regulated, while levels of other cell cycle proteins remained unchanged. This regulation was dependent on STAT5, arguing for FLT3-ITD-dependent transcriptional regulation of CDC25A. CDC25 inhibitors triggered proliferation arrest and cell death of FLT3-ITD as well as FLT3-ITD/TKD AC-220 resistant cells, but not of FLT3-wt cells. Consistently, RNA interference-mediated knock-down of CDC25A reduced the proliferation of FLT3-ITD cell lines. Finally, the clonogenic capacity of primary FLT3-ITD AML cells was reduced by the CDC25 inhibitor IRC-083864, while FLT3-wt AML and normal CD34+ myeloid cells were unaffected. In good agreement, in a cohort of 100 samples from AML patients with intermediate-risk cytogenetics, high levels of CDC25A mRNA were predictive of higher clonogenic potential in FLT3-ITD+ samples, not in FLT3-wt ones.Importantly, pharmacological inhibition as well as RNA interference-mediated knock-down of CDC25A also induced monocytic differentiation of FLT3-ITD positive cells, as judged by cell surface markers expression, morphological modifications, and C/EBPα phosphorylation. CDC25 inhibition also re-induced monocytic differentiation in primary AML blasts carrying the FLT3-ITD mutation, but not in blasts expressing wild type FLT3. Altogether, these data identify CDC25A as an early cell cycle transducer of FLT3-ITD oncogenic signaling, and as a promising target to inhibit proliferation and re-induce differentiation of FLT3-ITD AML cells.
Asunto(s)
Diferenciación Celular , Proliferación Celular , Leucemia Mieloide Aguda/enzimología , Fosfatasas cdc25/metabolismo , Tirosina Quinasa 3 Similar a fms/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos/farmacología , Benzotiazoles/farmacología , Benzoxazoles/farmacología , Puntos de Control del Ciclo Celular , Muerte Celular , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Niño , Técnicas de Cocultivo , Inhibidores Enzimáticos/farmacología , Femenino , Regulación Enzimológica de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Células HL-60 , Humanos , Células K562 , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Masculino , Persona de Mediana Edad , Mutación , Interferencia de ARN , ARN Mensajero/genética , ARN Mensajero/metabolismo , Factor de Transcripción STAT5/metabolismo , Transducción de Señal , Secuencias Repetidas en Tándem , Factores de Tiempo , Transcripción Genética , Transfección , Células Tumorales Cultivadas , Fosfatasas cdc25/antagonistas & inhibidores , Fosfatasas cdc25/genética , Tirosina Quinasa 3 Similar a fms/genéticaRESUMEN
Acute myeloid leukemias (AML) with myelodysplasia-related changes (AML-MRC) are defined by the presence of multilineage dysplasia (MLD), and/or myelodysplastic syndrome (MDS)-related cytogenetics, and/or previous MDS. The goal of this study was to identify distinct biological and prognostic subgroups based on mutations of ASXL1, RUNX1, DNMT3A, NPM1, FLT3 and TP53 in 125 AML-MRC patients according to the presence of MLD, cytogenetics and outcome. ASXL1 mutations (n=26, 21%) were associated with a higher proportion of marrow dysgranulopoiesis (mutant vs. wild-type: 75% vs. 55%, p=0.030) and were mostly found in intermediate cytogenetic AML (23/26) in which they predicted inferior 2-year overall survival (OS, mutant vs. wild-type: 14% vs. 37%, p=0.030). TP53 mutations (n=28, 22%) were mostly found in complex karyotype AML (26/28) and predicted poor outcome within unfavorable cytogenetic risk AML (mutant vs. wild-type: 9% vs. 40%, p=0.040). In multivariate analysis, the presence of either ASXL1 or TP53 mutation was the only independent factor associated with shorter OS (HR, 95%CI: 2.53, 1.40-4.60, p=0.002) while MLD, MDS-related cytogenetics and previous MDS history did not influence OS. We conclude that ASXL1 and TP53 mutations identify two molecular subgroups among AML-MRCs, with specific poor prognosis. This could be useful for future diagnostic and prognostic classifications.
Asunto(s)
Leucemia Mieloide Aguda/genética , Mutación , Síndromes Mielodisplásicos/genética , Proteínas Represoras/genética , Proteína p53 Supresora de Tumor/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Leucemia Mieloide Aguda/clasificación , Leucemia Mieloide Aguda/patología , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/clasificación , Síndromes Mielodisplásicos/patología , Nucleofosmina , Pronóstico , Proteínas Represoras/metabolismo , Análisis de Supervivencia , Proteína p53 Supresora de Tumor/metabolismo , Adulto JovenRESUMEN
Hemophagocytic lymphohistiocytosis is a condition of immune dysregulation characterized by severe organ damage induced by a hyperinflammatory response and uncontrolled T-cell and macrophage activation. Secondary hemophagocytic lymphohistiocytosis typically occurs in association with severe infections or malignancies. Patients with acute myeloid leukemia may be prone to develop hemophagocytic lymphohistiocytosis because of an impaired immune response and a high susceptibility to severe infections. In a series of 343 patients treated by intensive chemotherapy over a 5-year period in our center, we identified 32 patients (9.3%) with fever, very high ferritin levels, and marrow hemophagocytosis (i.e. patients with hemophagocytic lymphohistiocytosis). Compared to patients without hemophagocytic lymphohistiocytosis, these 32 patients had hepatomegaly, pulmonary or neurological symptoms, liver abnormalities, lower platelet count and higher levels of C-reactive protein as well as prolonged pancytopenia. A microbial etiology for the hemophagocytosis was documented in 24 patients: 14 bacterial infections, 9 Herpesviridae infections and 11 fungal infections. The treatment of hemophagocytic lymphohistiocytosis consisted of corticosteroids and/or intravenous immunoglobulins along with adapted antimicrobial therapy. Patients with hemophagocytic lymphohistiocytosis had a median overall survival of 14.9 months, which was significantly shorter than that of patients without hemophagocytic lymphohistiocytosis (22.1 months) (P=0.0016). Hemophagocytic lymphohistiocytosis was significantly associated with a higher rate of induction failure, mainly due to deaths in aplasia. Hemophagocytic lymphohistiocytosis can be diagnosed in up to 10% of patients with acute myeloid leukemia undergoing intensive chemotherapy and is associated with early mortality. Fever, very high ferritin levels and marrow hemophagocytosis represent the cornerstone of the diagnosis. Further biological studies are needed to better characterize and recognize this syndrome in patients with acute myeloid leukemia.
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Leucemia Mieloide Aguda/complicaciones , Leucemia Mieloide Aguda/tratamiento farmacológico , Linfohistiocitosis Hemofagocítica/etiología , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Médula Ósea/metabolismo , Médula Ósea/patología , Femenino , Ferritinas/metabolismo , Humanos , Inmunoglobulinas Intravenosas/uso terapéutico , Inmunosupresores/uso terapéutico , Leucemia Mieloide Aguda/diagnóstico , Linfohistiocitosis Hemofagocítica/diagnóstico , Linfohistiocitosis Hemofagocítica/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Resultado del TratamientoRESUMEN
In acute myeloid leukemia (AML), new strategies assess the potential benefit of genetically targeted therapy at diagnosis. This implies waiting for laboratory tests and therefore a delay in initiation of chemotherapy. We studied the impact of time from diagnosis to treatment (TDT) on overall survival, early death, and response rate in a retrospective series of 599 newly diagnosed AML patients treated by induction chemotherapy between 2000 and 2009. The effect of TDT was assessed using multivariate analysis. TDT was analyzed as a continuous variable using a specific polynomial function to model the shape and form of the relationship. The median TDT was 8 days (interquartile range, 4-16) and was significantly longer in patients with a white blood cell count (WBC) <50 Giga per liter (G/L) (P < .0001) and in older patients (P = .0004). In multivariate analysis, TDT had no impact on overall survival (P = .4095) compared with age >60 years, secondary AML, WBC >50 G/L, European LeukemiaNet risk groups, and Eastern Cooperative Oncology Group performance status. Furthermore, TDT was not associated with response rate and early death. Thus, waiting a short period of time for laboratory tests to characterize leukemias better and design adapted therapeutic strategies at diagnosis seems possible.
Asunto(s)
Citarabina/uso terapéutico , Daunorrubicina/uso terapéutico , Idarrubicina/uso terapéutico , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/mortalidad , Tiempo de Tratamiento/estadística & datos numéricos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antibióticos Antineoplásicos/uso terapéutico , Antimetabolitos Antineoplásicos/uso terapéutico , Femenino , Estudios de Seguimiento , Humanos , Estimación de Kaplan-Meier , Leucemia Mieloide Aguda/diagnóstico , Masculino , Persona de Mediana Edad , Análisis Multivariante , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento , Adulto JovenRESUMEN
SAR103168, a tyrosine kinase inhibitor of the pyrido [2,3-d] pyridimidine subclass, inhibited the kinase activities of the entire Src kinase family, Abl kinase, angiogenic receptor kinases (vascular endothelial growth factor receptor [VEGFR] 1 and 2), Tie2, platelet derived growth factor (PDGF), fibroblast growth factor receptor (FGFR) 1 and 3, and epidermal growth factor receptor (EGFR). SAR103168 was a potent Src inhibitor, with 50% inhibitory concentration (IC50) = 0.65 ± 0.02 nM (at 100 µM ATP), targeting the auto-phosphorylation of the kinase domain (Src(260-535)) and activity of the phosphorylated kinase. Phosphorylation of Src, Lyn and Src downstream signaling pathways (PYK2, P-130CAS, FAK, JNK and MAPK) were inhibited in a dose-dependent manner. SAR103168 inhibited the phosphorylation of STAT5 in KG1 cells and fresh cells from patients with acute myeloid leukemia (AML). SAR103168 inhibited proliferation and induced apoptosis in acute and chronic myeloid leukemic cells at nanomolar IC50. SAR103168 induced anti-proliferation of leukemic progenitors (CFU-L) from 29 patients with AML, and > 85% of AML patient samples were sensitive to SAR103168. These antagonist activities of SAR103168 were independent of FLT3 expression. SAR103168 treatment was effective in 50% of high-risk patient samples carrying chromosome 7 abnormalities or complex rearrangement. SAR103168 administration (intravenous or oral) impaired tumor growth and induced tumor regression in animals bearing human AML leukemic cells, correlating with potent inhibition of Src downstream signaling pathways in AML tumors. SAR103168 showed potent anti-tumor activity in SCID (severe combined immunodeficiency) mice bearing AML (KG1, EOL-1, Kasumi-1, CTV1) and chronic myeloid leukemia (CML) (K562) tumors. The combination of cytarabine and SAR103168 showed synergistic activity in AML and CML tumor models. These results highlight the therapeutic potential of SAR103168 in myeloid leukemias and support the rationale for clinical investigations.
Asunto(s)
Antineoplásicos/farmacología , Leucemia Mieloide/enzimología , Inhibidores de Proteínas Quinasas/farmacología , Piridinas/uso terapéutico , Pirimidinas/uso terapéutico , Animales , Antineoplásicos/uso terapéutico , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Leucemia Mieloide/tratamiento farmacológico , Leucemia Mieloide/metabolismo , Ratones , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/metabolismo , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Transducción de Señal/efectos de los fármacos , Ensayo de Tumor de Célula Madre , Ensayos Antitumor por Modelo de Xenoinjerto , Familia-src Quinasas/antagonistas & inhibidoresRESUMEN
BACKGROUND: The assessment of anticancer agents to treat leukemia needs to have animal models closer to the human pathology such as implantation in immunodeficient mice of leukemic cells from patient samples. A sensitive and early detection of tumor cells in these orthotopic models is a prerequisite for monitoring engraftment of leukemic cells and their dissemination in mice. Therefore, we developed a fluorescent antibody based strategy to detect leukemic foci in mice bearing patient-derived leukemic cells using fluorescence reflectance imaging (FRI) to determine when to start treatments with novel antitumor agents. METHODS: Two mAbs against the CD44 human myeloid marker or the CD45 human leukocyte marker were labeled with Alexa Fluor 750 and administered to leukemia-bearing mice after having verified the immunoreactivity in vitro. Bioluminescent leukemic cells (HL60-Luc) were used to compare the colocalization of the fluorescent mAb with these cells. The impact of the labeled antibodies on disease progression was further determined. Finally, the fluorescent hCD45 mAb was tested in mice engrafted with human leukemic cells. RESULTS: The probe labeling did not modify the immunoreactivity of the mAbs. There was a satisfactory correlation between bioluminescence imaging (BLI) and FRI and low doses of mAb were sufficient to detect leukemic foci. However, anti-hCD44 mAb had a strong impact on the tumor proliferation contrary to anti-hCD45 mAb. The use of anti-hCD45 mAb allowed the detection of leukemic patient cells engrafted onto NOD/SCID mice. CONCLUSIONS: A mAb labeled with a near infrared fluorochrome is useful to detect leukemic foci in disseminated models provided that its potential impact on tumor proliferation has been thoroughly documented.
Asunto(s)
Anticuerpos Monoclonales/inmunología , Colorantes Fluorescentes/metabolismo , Imagenología Tridimensional/métodos , Leucemia/diagnóstico , Leucemia/patología , Espectroscopía Infrarroja Corta/métodos , Animales , Anticuerpos Monoclonales/administración & dosificación , Línea Celular Tumoral , Transformación Celular Neoplásica/patología , Modelos Animales de Enfermedad , Citometría de Flujo , Humanos , Inyecciones Intravenosas , Leucemia Mieloide Aguda/patología , Antígenos Comunes de Leucocito/metabolismo , Longevidad , Mediciones Luminiscentes , Ratones , Ratones SCID , Reproducibilidad de los ResultadosRESUMEN
There has been considerable interest in targeting cell cycle checkpoints particularly in emerging and alternative anticancer strategies. Here, we show that checkpoint abrogation by AZD7762, a potent and selective CHK1/2 kinase inhibitor enhances genotoxic treatment efficacy in immature KG1a leukemic cell line and in AML patient samples, particularly those with a complex karyotype, which display major genomic instability and chemoresistance. Furthermore, these data suggest that constitutive DNA-damage level might be useful markers to select AML patients susceptible to receive checkpoint inhibitor in combination with conventional chemotherapy. Moreover, this study demonstrates for the first time that AZD7762 inhibitor targets the CD34(+)CD38(-)CD123(+) primitive leukemic progenitors, which are responsible for the majority of AML patients relapse. Finally, CHK1 inhibition does not seem to affect clonogenic potential of normal hematopoietic progenitors.
Asunto(s)
Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/enzimología , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Quinasas/metabolismo , Tiofenos/farmacología , Urea/análogos & derivados , Anciano , Apoptosis/efectos de los fármacos , Apoptosis/genética , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1) , Humanos , Cariotipo , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Persona de Mediana Edad , Terapia Molecular Dirigida , Proteínas Quinasas/genética , Urea/farmacologíaRESUMEN
The JAK2(V617F) mutation is present in the majority of patients with polycythemia vera and one-half of those with essential thrombocythemia and primary myelofibrosis. JAK2(V617F) is a gain-of-function mutation resulting in constitutive JAK2 signaling involved in the pathogenesis of these diseases. JAK2(V617F) has been shown to promote S-phase entry. Here, we demonstrate that the CDC25A phosphatase, a key regulator of the G1/S cell-cycle transition, is constitutively overexpressed in JAK2(V617F)-positive cell lines, JAK2-mutated patient CD36(+) progenitors, and in vitro-differentiated proerythroblasts. Accordingly, CDC25A is overexpressed in BM and spleen of Jak2(V617F) knock-in mice compared with wild-type littermates. By using murine FDC-P1-EPOR and human HEL and SET-2 cell lines, we found that JAK2(V617F)-induced CDC25A up-regulation was caused neither by increased CDC25A transcription or stability nor by the involvement of its upstream regulators Akt and MAPK. Instead, our results suggest that CDC25A is regulated at the translational level through STAT5 and the translational initiation factor eIF2α. CDC25A inhibition reduces the clonogenic and proliferative potential of JAK2(V617F)-expressing cell lines and erythroid progenitors while moderately affecting normal erythroid differentiation. These results suggest that CDC25A deregulation may be involved in hematopoietic cells expansion in JAK2(V617F) patients, making this protein an attracting potential therapeutic target.
Asunto(s)
Janus Quinasa 2/genética , Fosfatasas cdc25/genética , Sustitución de Aminoácidos/fisiología , Animales , Ciclo Celular/genética , Células Cultivadas , Activación Enzimática/genética , Regulación Leucémica de la Expresión Génica/genética , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/patología , Células Madre Hematopoyéticas/metabolismo , Humanos , Janus Quinasa 2/metabolismo , Ratones , Proteínas Mutantes/genética , Oncogenes/genética , Fenilalanina/genética , Regulación hacia Arriba , Valina/genética , Fosfatasas cdc25/metabolismoRESUMEN
Mutations in DNMT3A encoding DNA methyltransferase 3A were recently described in patients with acute myeloid leukemia. To assess their prognostic significance, we determined the mutational status of DNMT3A exon 23 in 288 patients with AML excluding acute promyelocytic leukemia, aged from 18 to 65 years and treated in Toulouse University Hospital. A mutation was detected in 39 patients (13.5%). All DNMT3A exon 23+ patients had intermediate-risk cytogenetics. Mutations significantly correlated with a higher WBC count (p less than 0.001), NPM1 and FLT3-ITD mutations (p=0.027). DNMT3A mutations were conserved through xenotransplantation in immunodeficient mice. No difference in outcome between DNMT3A exon 23+ and DNMT3A exon 23- patients was found even if the results were stratified by NPM1 or FLT3-ITD status. However, DNMT3A exon 23+ patients had better median DFS (not reached vs 11.6 months, p=0.009) and OS (not reached vs 14.3 months, p=0.005) as compared to DNMT3A exon 23- patients when treated with idarubicin, whereas patients treated with daunorubicin had similar outcome regardless the DNMT3A status. This study shows that DNMT3A mutations have no impact on outcome but could be a predictive factor for response to idarubicin and thus, could have a direct influence in the way AML patients should be managed.
Asunto(s)
Antibióticos Antineoplásicos/uso terapéutico , ADN (Citosina-5-)-Metiltransferasas/genética , Daunorrubicina/uso terapéutico , Idarrubicina/uso terapéutico , Leucemia Mieloide Aguda/genética , Adolescente , Adulto , Anciano , Animales , ADN Metiltransferasa 3A , Análisis Mutacional de ADN , Supervivencia sin Enfermedad , Resistencia a Antineoplásicos/genética , Exones , Femenino , Humanos , Estimación de Kaplan-Meier , Leucemia Mieloide Aguda/tratamiento farmacológico , Masculino , Ratones , Ratones SCID , Persona de Mediana Edad , Mutación , Nucleofosmina , Pronóstico , Resultado del Tratamiento , Ensayos Antitumor por Modelo de Xenoinjerto , Adulto JovenRESUMEN
BACKGROUND: Acute myeloid leukemias arise from a rare population of leukemic cells, known as leukemic stem cells, which initiate the disease and contribute to frequent relapses. Although the phenotype of these cells remains unclear in most patients, these cells are enriched within the CD34(+)CD38(low/-) compartment expressing the interleukin-3 alpha chain receptor, CD123. The aim of this study was to determine the prognostic value of the percentage of blasts with the CD34(+)CD38(low/-)CD123(+) phenotype. DESIGN AND METHODS: The percentage of CD34(+)CD38(low/-)CD123(+) cells in the blast population was determined at diagnosis using flow cytometry. One hundred and eleven patients under 65 years of age with de novo acute myeloid leukemia and treated with intensive chemotherapy were retrospectively included in the study. Correlations with complete response, disease-free survival and overall survival were evaluated with univariate and multivariate analyses. RESULTS: A proportion of CD34(+)CD38(low/-)CD123(+) cells greater than 15% at diagnosis and an unfavorable karyotype were significantly correlated with a lack of complete response. By logistic regression analysis, a percentage of CD34(+)CD38(low/-)CD123(+) higher than 15% retained significance with an odds ratio of 0.33 (0.1-0.97; P=0.044). A greater than 1% population of CD34(+)CD38(low/-)CD123(+) cells negatively affected disease-free survival (0.9 versus 4.7 years; P<0.0001) and overall survival (1.25 years versus median not reached; P<0.0001). A greater than 1% population of CD34(+)CD38(low/-)CD123(+) cells retained prognostic significance for both parameters after multivariate analysis. CONCLUSIONS: The percentage of CD34(+)CD38(low/-)CD123(+) leukemic cells at diagnosis was significantly correlated with response to treatment and survival. This prognostic marker might be easily adopted in clinical practice to rapidly identify patients at risk of treatment failure.
Asunto(s)
ADP-Ribosil Ciclasa 1/sangre , Antígenos CD34/sangre , Antígenos de Neoplasias/sangre , Crisis Blástica/sangre , Crisis Blástica/diagnóstico , Subunidad alfa del Receptor de Interleucina-3/sangre , Leucemia Mieloide Aguda/sangre , Leucemia Mieloide Aguda/diagnóstico , Glicoproteínas de Membrana/sangre , Adulto , Anciano , Crisis Blástica/mortalidad , Crisis Blástica/terapia , Femenino , Humanos , Leucemia Mieloide Aguda/mortalidad , Leucemia Mieloide Aguda/terapia , Recuento de Leucocitos , Masculino , Persona de Mediana Edad , PronósticoRESUMEN
Acute basophilic leukemia (ABL) is a rare subtype of acute leukemia with clinical features and symptoms related to hyperhistaminemia because of excessive growth of basophils. No known recurrent cytogenetic abnormality is associated with this leukemia. Rare cases of t(X;6)(p11;q23) translocation have been described but these were sporadic. We report here 4 cases of ABL with a t(X;6)(p11;q23) translocation occurring in male infants. Because of its location on chromosome 6q23, MYB was a good candidate gene. Our molecular investigations, based on fluorescence in situ hybridization and rapid amplification of cDNA ends, revealed that the translocation generated a MYB-GATA1 fusion gene. Expression of MYB-GATA1 in mouse lineage-negative cells committed them to the granulocyte lineage and blocked at an early stage of differentiation. Taken together, these results establish, for the first time, a link between a recurrent chromosomal translocation and the development of this particular subtype of infant leukemia.
Asunto(s)
Factor de Transcripción GATA1/genética , Leucemia Basofílica Aguda/genética , Proteínas de Fusión Oncogénica/genética , Oncogenes/genética , Proteínas Proto-Oncogénicas c-myb/genética , Animales , Western Blotting , Cromosomas Humanos Par 6/genética , Cromosomas Humanos X/genética , Femenino , Humanos , Hibridación Fluorescente in Situ , Lactante , Cariotipificación , Masculino , Ratones , Ratones Endogámicos C57BL , Pronóstico , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Translocación Genética , Ensayo de Tumor de Célula MadreRESUMEN
In search for compounds able to reduce cell adhesion-mediated drug resistance (CAM-DR), we studied effects of Hammada scoparia extracts on leukemic cells adherent or in suspension. We show that H. scoparia flavonoidic fraction and its compound rutin induce apoptosis specifically in adherent leukemic cells and abolish CAM-DR. Importantly, rutin inhibited survival of adherent leukemic progenitors (CD34(+)38(-)123(+)) but spared normal progenitors (CD34(+)38(-)). The pro-apoptotic effects of rutin were correlated with a decrease of active GSK3ß and inhibitors of GSK3ß reproduced rutin-induced cytotoxicity. This study uncovers the potential of H. scoparia flavonoids and rutin to overcome CAM-DR in acute myeloid leukemia.
Asunto(s)
Apoptosis/efectos de los fármacos , Adhesión Celular/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/patología , Fitoterapia , Rutina/farmacología , Scoparia/química , Antígenos CD34/metabolismo , Western Blotting , Células Cultivadas , Flavonoides/farmacología , Citometría de Flujo , Glucógeno Sintasa Quinasa 3/antagonistas & inhibidores , Glucógeno Sintasa Quinasa 3/metabolismo , Glucógeno Sintasa Quinasa 3 beta , Células Madre Hematopoyéticas/efectos de los fármacos , Células Madre Hematopoyéticas/metabolismo , Humanos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización DesorciónRESUMEN
Despite substantial progress in the treatment of AML, a proportion of patients do not achieve first complete remission (1(st) CR) with the induction chemotherapy, and, among patients achieving it, a majority is expected to relapse within three years. As allogeneic hematopoietic stem cell transplantation has been established as the most effective form of antileukemic therapy in patients with AML in remission, many studies have focused on the reconstitution and the functionality of the innate immune system in this context, especially regarding cytotoxic effectors such as natural killer (NK) cells. On the contrary, very few data are available concerning the innate immune system of patients in 1st CR. Herein we investigated the phenotype of autologous NK cells of AML patients in 1st CR. We showed that immature NK cells were pre-eminent in the blood of these patients and that this immature phenotype was persistent during the first months after 1st CR.
Asunto(s)
Inmunidad Innata , Células Asesinas Naturales/inmunología , Leucemia Mieloide Aguda/inmunología , Células Progenitoras Linfoides/inmunología , Receptores de Células Asesinas Naturales/metabolismo , Antígeno CD56/metabolismo , Estudios de Seguimiento , Humanos , Células Asesinas Naturales/metabolismo , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/terapia , Recuento de Linfocitos , Células Progenitoras Linfoides/metabolismo , Persona de Mediana Edad , Subfamília C de Receptores Similares a Lectina de Células NK/metabolismo , Receptores KIR/metabolismo , Inducción de RemisiónRESUMEN
NPM-ALK (nucleophosmin-anaplastic lymphoma kinase) and TPM3-ALK (nonmuscular tropomyosin 3-anaplastic lymphoma kinase) are oncogenic tyrosine kinases implicated in the pathogenesis of human ALK-positive lymphoma. We report here the development of novel conditional mouse models for ALK-induced lymphomagenesis, with the use of the tetracycline regulatory system under the control of the EmuSRalpha enhancer/promoter. The expression of either oncogene resulted in the arrest of the differentiation of early B cells and lymphomagenesis. We also observed the development of skin keratoacanthoma lesions, probably because of aberrant ALK expression in keratinocytes. The inactivation of the ALK oncogene on doxycycline treatment was sufficient to induce sustained regression of both hematopoietic tumors and skin disease. Importantly, treatment with the specific ALK inhibitor (PF-2341066) also reversed the pathologic states, showing the value of these mouse models for the validation of ALK tyrosine kinase inhibitors. Thus, our results show (1) that NPM-ALK and TPM3-ALK oncogenes are sufficient for lymphoma/leukemia development and required for tumor maintenance, hence validating ALK as potentially effective therapeutic target; and (2) for the first time, in vivo, the equal tumorigenic potential of the NPM-ALK and TPM3-ALK oncogenic tyrosine kinases. Our models offer a new tool to investigate in vivo the molecular mechanisms associated with ALK-induced lymphoproliferative disorders.
Asunto(s)
Leucemia de Células B/patología , Linfoma de Células B/patología , Proteínas Tirosina Quinasas/genética , Tropomiosina/genética , Quinasa de Linfoma Anaplásico , Animales , Apoptosis , Western Blotting , Diferenciación Celular , Proliferación Celular , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Humanos , Immunoblotting , Técnicas para Inmunoenzimas , Integrasas/metabolismo , Leucemia de Células B/genética , Leucemia de Células B/metabolismo , Linfoma de Células B/genética , Linfoma de Células B/metabolismo , Ratones , Ratones Transgénicos , Proteínas Tirosina Quinasas/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Proteínas Tirosina Quinasas Receptoras , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Tropomiosina/metabolismoAsunto(s)
Enfermedades de la Aorta/etiología , Leucemia Mieloide Aguda/complicaciones , Sarcoma Mieloide/diagnóstico , Trombosis/etiología , Neoplasias Uterinas/diagnóstico , Adulto , Femenino , Humanos , Leucemia Mieloide Aguda/genética , Proteínas de Ensamble de Clatrina Monoméricas/genética , Factores de Riesgo , Sarcoma Mieloide/complicaciones , Factores de Transcripción/genética , Neoplasias Uterinas/complicacionesRESUMEN
Genomic instability in solid tumors participates in the oncogenetic process and is associated with the activation of the DNA damage response pathway. Here, we report the activation of the constitutive DNA damage and checkpoint pathway associated with complex karyotypes in samples from patients with acute myeloid leukemia (AML). We show that antagonizing CHK1 kinase with a small inhibitory compound or by RNA interference strongly reduces the clonogenic properties of high-DNA damage level AML samples, particularly those with complex karyotypes. Moreover, we observe a beneficial effect of CHK1 inhibition in high-DNA damage level AML samples treated with 1-beta-d-arabinofuranosylcytosine. In contrast, CHK1 inhibition has no effect on the clonogenic properties of normal hematopoietic progenitors. All together, our results indicate that CHK1 inhibition may represent an attractive therapeutic opportunity in AML with complex karyotype.
Asunto(s)
Aberraciones Cromosómicas , Daño del ADN/fisiología , Leucemia Mieloide Aguda/genética , Proteínas Quinasas/metabolismo , Transducción de Señal/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos/farmacología , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1) , Niño , Citometría de Flujo , Técnica del Anticuerpo Fluorescente , Células Madre Hematopoyéticas/efectos de los fármacos , Humanos , Persona de Mediana Edad , Interferencia de ARN , Transducción de Señal/efectos de los fármacos , Estaurosporina/análogos & derivados , Estaurosporina/farmacologíaRESUMEN
Polo-Kinase 1 (PLK1) is a key cell cycle regulator that is necessary for checkpoint recovery after DNA damage-induced G2 arrest. We have examined the effects of PLK inhibition in Acute Myelocytic Leukaemia (AML) cells, whose resistance to genotoxic agents is thought to be associated with checkpoint reinforcement. We report that in U937 AML cells, PLK1 participates in checkpoint recovery, and that inhibition of PLK by the GW843682X compound results in mitotic accumulation and apoptosis. We also found that when challenged with VP-16, inhibition of PLK1 prevented U937 cells from checkpoint exit. Finally, we found that treatment with GW843682X slightly reduced genotoxic-induced inhibition of colony formation efficiency of primary leukaemia cells (CFU-L) from AML patients.