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1.
Transplantation ; 100(8): 1732-9, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26528768

RESUMEN

BACKGROUND: The impact of antithymocyte globulin (ATG) in the setting of a myeloablative conditioning transplantation remains controversial, especially when using bone marrow (BM) as the stem cell source. METHODS: We therefore conducted a retrospective analysis to investigate the impact of ATG in patients with acute myeloid leukemia or myelodysplastic syndrome receiving myeloablative conditioning followed by a matched 10 of 10 unrelated donor transplant from BM or peripheral blood stem cells (PBSCs). Our study included 356 patients conditioned with cyclophosphamide associated with fractionated total body irradiation or busulfan. RESULTS: Median follow-up was 17.6 months (range, 0-156). The ATG and PBSCs were the only variables that independently decreased the cumulative incidence (CI) of chronic graft-versus-host disease (GvHD) (hazards ratio [HR], 0.4; 95% CI, 0.21-0.73; P < 0.01; and HR, 0.53; 95% CI, 0.30-0.90; P = 0.02, respectively). The ATG had no impact on overall survival, disease-free survival, relapse, and nonrelapse mortality. In the PBSC group (n = 139), ATG was associated with a lower CI of both grades III to IV acute GvHD (HR, 0.17; 95% CI, 0.03-0.91; P = 0.04), chronic GvHD (HR, 0.31; 95% CI, 0.11-0.87; P = 0.03), and GvHD-free/relapse-free survival (HR, 0.48; 95% CI, 0.29-0.80; P < 0.01), whereas these correlations were not significant in the group of patients (n = 217) receiving BM (HR, 0.36; 95% CI, 0.11-1.93; P = 0.06 for grade III-IV acute GvHD; HR, 0.49; 95% CI, 0.22-1.06; P = 0.08 for chronic GvHD; and HR, 0.69; 95% CI, 0.46-1.01; P = 0.06 for GvHD-free/relapse-free survival). CONCLUSIONS: Although our results confirm the recommendation for ATG to be added after PBSC transplantation, no obvious benefit was identified using this approach in the setting of BM transplantation. Only prospective studies may yield definitive answers to this question.


Asunto(s)
Suero Antilinfocítico/uso terapéutico , Trasplante de Médula Ósea , Antígenos HLA/inmunología , Inmunosupresores/uso terapéutico , Leucemia Mieloide Aguda/cirugía , Síndromes Mielodisplásicos/cirugía , Trasplante de Células Madre de Sangre Periférica , Acondicionamiento Pretrasplante/métodos , Donante no Emparentado , Adolescente , Adulto , Suero Antilinfocítico/efectos adversos , Trasplante de Médula Ósea/métodos , Trasplante de Médula Ósea/mortalidad , Busulfano/uso terapéutico , Distribución de Chi-Cuadrado , Enfermedad Crónica , Ciclofosfamida/uso terapéutico , Supervivencia sin Enfermedad , Fraccionamiento de la Dosis de Radiación , Femenino , Francia , Enfermedad Injerto contra Huésped/inmunología , Enfermedad Injerto contra Huésped/prevención & control , Histocompatibilidad , Prueba de Histocompatibilidad , Humanos , Inmunosupresores/efectos adversos , Estimación de Kaplan-Meier , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/inmunología , Leucemia Mieloide Aguda/mortalidad , Masculino , Persona de Mediana Edad , Análisis Multivariante , Agonistas Mieloablativos/uso terapéutico , Síndromes Mielodisplásicos/diagnóstico , Síndromes Mielodisplásicos/inmunología , Síndromes Mielodisplásicos/mortalidad , Trasplante de Células Madre de Sangre Periférica/efectos adversos , Trasplante de Células Madre de Sangre Periférica/métodos , Trasplante de Células Madre de Sangre Periférica/mortalidad , Modelos de Riesgos Proporcionales , Recurrencia , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Acondicionamiento Pretrasplante/efectos adversos , Acondicionamiento Pretrasplante/mortalidad , Resultado del Tratamiento , Irradiación Corporal Total , Adulto Joven
2.
J Acquir Immune Defic Syndr ; 68(2): 204-8, 2015 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-25590273

RESUMEN

BACKGROUND: Viremia copy-years (VCY) has been reported as a short-term predictor of mortality. We evaluated the association of this parameter with 10-year outcome within the APROCO-COPILOTE cohort. METHODS: Prospective data from 1281 HIV-1-infected patients who started a first protease inhibitor-containing regimen in 1997-1999 were analyzed. Patients with baseline plasma viral load (pVL) > 500 copies per milliliter and at least 2 pVL measures from the eighth month of follow-up were selected. VCY was calculated individually over the follow-up as the area under the pVL curve. Multivariate Cox models analyzed the relation between all-cause mortality and the following variables: age, sex, geographical origin, transmission group, HIV infection duration, ART-naive, pVL at baseline, time-dependent CD4 count, and VCY. RESULTS: Nine hundred seventy-nine patients were followed up for a median of 10 years (interquartile range: 5-11.5). At baseline, median (interquartile range) values for duration of HIV infection, pVL, and CD4 cell count were 43 (4-95) months, 4.6 (3.9-5.2) log10 copies per milliliter, and 278 (125-416) cells per cubic millimeter, respectively. At censoring date, 77 patients (8%) had died. VCY >1.4 log10 copies × yrs/mL was an independent predictor of death (hazard ratio: 2.0; 95% confidence interval: 1.2 to 3.5), which was no longer the case after adjustment for the latest pVL value [risk ratio (RR): 1.2 for 1 additional log10 copies per milliliter; 95% confidence interval: 1.1 to 1.4]. CONCLUSIONS: VCY was associated with mortality in HIV-infected patients under combined antiretroviral therapy but did not overweigh the predictive value of the latest pVL. VCY might be more useful as a marker of persistent viral replication than for routine clinical care.


Asunto(s)
Antirretrovirales/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , Inhibidores de la Proteasa del VIH/uso terapéutico , VIH-1/aislamiento & purificación , Viremia , Adulto , Recuento de Linfocito CD4 , Estudios de Cohortes , Demografía , Femenino , Infecciones por VIH/mortalidad , Humanos , Masculino , Plasma/virología , Pronóstico , Estudios Prospectivos , Análisis de Supervivencia , Carga Viral
3.
Am J Hematol ; 88(9): 780-3, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23757315

RESUMEN

IPSS-R classifies cytogenetic abnormalities into five prognostic groups for survival. Monosomal karyotype (MK) is not a subgroup of IPSS-R. Additional prognostic information from MK in poor and very poor karyotype has been recently shown. The aim of our study was to determine the prognostic value of IPSS-R and MK for response and survival in AZA-treated high-risk MDS and AML with 20-30% of blasts patients. The study population included 154 patients who were classified according to IPSS-R. IPSS-R was not predictive of response (intermediate, 64%; poor, 44%; very poor, 56%; P = 0.28) or survival (intermediate, 25 months; poor, 12 months; very poor, 11 months; P = 0.14). Twenty-one patients (15%) presented with MK and had a median OS of 9 months. Patients with a very high IPSS-R score without MK had a median OS of 15 months, while patients with a high IPSS-R score without MK had a median OS of 13 months (P = 0.18). We reclassified patients into the following three groups to include MK status: very high (MK only; OS median: 9 months), high (very high IPSS-R without MK and high IPSS-R without MK; OS median: 14 months) and intermediate (OS median: 25 months). As in recent publication including MK prognostic, we confirmed that this classification was predictive for survival in AZA treated patients (P = 0.008). IPSS-R failed to discriminate between the prognostic subgroups. Stratification with MK has value in the prognosis of our cohort of AZA-treated patients.


Asunto(s)
Antimetabolitos Antineoplásicos/uso terapéutico , Azacitidina/uso terapéutico , Cariotipificación/clasificación , Leucemia Mieloide Aguda/tratamiento farmacológico , Monosomía , Síndromes Mielodisplásicos/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Cariotipo , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidad , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/genética , Síndromes Mielodisplásicos/mortalidad , Análisis de Supervivencia , Resultado del Tratamiento
4.
Oncotarget ; 3(12): 1557-65, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23238683

RESUMEN

The advent of tyrosine kinase inhibitor (TKI) therapy has considerably improved the survival of patients suffering chronic myelogenous leukemia (CML). Indeed, inhibition of BCR-ABL by imatinib, dasatinib or nilotinib triggers durable responses in most patients suffering from this disease. Moreover, resistance to imatinib due to kinase domain mutations can be generally circumvented using dasatinib or nilotinib, but the multi-resistant T315I mutation that is insensitive to these TKIs, remains to date a major clinical problem. In this line, ponatinib (AP24534) has emerged as a promising therapeutic option in patients with all kinds of BCR-ABL mutations, especially the T315I one. However and surprisingly, the effect of ponatinib has not been extensively studied on imatinib-resistant CML cell lines. Therefore, in the present study, we used several CML cell lines with different mechanisms of resistance to TKI to evaluate the effect of ponatinib on cell viability, apoptosis and signaling. Our results show that ponatinib is highly effective on both sensitive and resistant CML cell lines, whatever the mode of resistance and also on BaF3 murine B cells carrying native BCR-ABL or T315I mutation. We conclude that ponatinib could be effectively used for all types of TKI-resistant patients.


Asunto(s)
Antineoplásicos/farmacología , Resistencia a Antineoplásicos , Proteínas de Fusión bcr-abl/antagonistas & inhibidores , Imidazoles/farmacología , Leucemia Mielógena Crónica BCR-ABL Positiva/enzimología , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Piridazinas/farmacología , Animales , Apoptosis/efectos de los fármacos , Benzamidas/farmacología , Supervivencia Celular/efectos de los fármacos , Dasatinib , Relación Dosis-Respuesta a Droga , Resistencia a Antineoplásicos/genética , Proteínas de Fusión bcr-abl/genética , Proteínas de Fusión bcr-abl/metabolismo , Humanos , Mesilato de Imatinib , Concentración 50 Inhibidora , Células K562 , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Ratones , Mutación , Piperazinas/farmacología , Proteínas Tirosina Quinasas/genética , Proteínas Tirosina Quinasas/metabolismo , Pirimidinas/farmacología , Transducción de Señal/efectos de los fármacos , Tiazoles/farmacología , Células Tumorales Cultivadas
5.
Oncotarget ; 3(4): 490-501, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22577154

RESUMEN

Azacitidine is the leading compound to treat patients suffering myelodysplastic syndrome (MDS) or AML with less than 30% of blasts, but a majority of patients is primary refractory or rapidly relapses under treatment. These patients have a drastically reduced life expectancy as compared to sensitive patients. Therefore identifying predictive factors for AZA resistance is of great interest to propose alternative therapeutic strategies for non-responsive patients. We generated AZA-resistant myeloid cell line (SKM1-R) that exhibited increased expression of BCL2L10 an anti-apoptotic Bcl-2 member. Importantly, BCL2L10 knockdown sensitized SKM1-R cells to AZA effect suggesting that increased BCL2L10 expression is linked to AZA resistance in SKM1-R. We next established in 77 MDS patients that resistance to AZA is significantly correlated with the percentage of MDS or AML cells expressing BCL2L10. In addition, we showed that the proportion of BCL2L10 positive bone marrow cells can predict overall survival in MDS or AML patients. We propose a convenient assay in which the percentage of BCL2L10 expressing cells as assessed by flow cytometry is predictive of whether or not a patient will become resistant to AZA. Therefore, systematic determination of BCL2L10 expression could be of great interest in newly diagnosed and AZA-treated MDS patients.


Asunto(s)
Azacitidina/uso terapéutico , Resistencia a Antineoplásicos , Leucemia Mieloide Aguda/tratamiento farmacológico , Síndromes Mielodisplásicos/tratamiento farmacológico , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Biomarcadores Farmacológicos/metabolismo , Línea Celular Tumoral , Humanos , Leucemia Mieloide Aguda/patología , Síndromes Mielodisplásicos/patología , Valor Predictivo de las Pruebas , Pronóstico , Proteínas Proto-Oncogénicas c-bcl-2/genética , ARN Interferente Pequeño/genética , Análisis de Supervivencia , Transgenes/genética
6.
J Mol Cell Biol ; 4(4): 207-20, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22467682

RESUMEN

Chronic myelogenous leukemia (CML) is a cytogenetic disorder resulting from the expression of p210BCR-ABL. Imatinib, an inhibitor of BCR-ABL, has emerged as the leading compound to treat CML patients. Despite encouraging clinical results, resistance to imatinib represents a major drawback for therapy, as a substantial proportion of patients are refractory to this treatment. Recent publications have described the existence of a small cancer cell population with the potential to exhibit the phenotypic switch responsible for chemoresistance. To investigate the existence of such a chemoresistant cellular subpopulation in CML, we used a two-step approach of pulse and continuous selection by imatinib in different CML cell lines that allowed the emergence of a subpopulation of adherent cells (IM-R Adh) displaying an epithelial-mesenchymal transition (EMT)-like phenotype. Overexpression of several EMT markers was observed in this CML subpopulation, as well as in CD34(+) CML primary cells from patients who responded poorly to imatinib treatment. In response to imatinib, this CD44(high)/CD24(low) IM-R Adh subpopulation exhibited increased adhesion, transmigration and invasion in vitro and in vivo through specific overexpression of the αVß3 receptor. FAK/Akt pathway activation following integrin ß3 (ITGß3) engagement mediated the migration and invasion of IM-R Adh cells, whereas persistent activation of ERK counteracted BCR-ABL inhibition by imatinib, promoting cell adhesion-mediated resistance.


Asunto(s)
Benzamidas/farmacología , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Mesodermo/efectos de los fármacos , Mesodermo/patología , Piperazinas/farmacología , Pirimidinas/farmacología , Animales , Adhesión Celular/efectos de los fármacos , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Transición Epitelial-Mesenquimal/efectos de los fármacos , Humanos , Mesilato de Imatinib , Integrina alfaVbeta3/metabolismo , Ratones , Fenotipo
7.
J Immunother ; 35(2): 154-8, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22306903

RESUMEN

There is now substantial evidence that imatinib may affect immune responses, especially those mediated by T lymphocytes. Fas (CD95/Apo-1), a cell death receptor, is a key regulator of the immune system. We have explored the consequences of treatment on the Fas system in chronic myeloid leukemia patients treated with imatinib. In comparison with healthy controls, we found not only a mild blood lymphopenia but also impairment of phytohemagglutinin activation in CD4Fas and CD8Fas lymphocytes of imatinib-treated patients. Moreover, these lymphocyte populations were more sensitive to FasL-induced cell death in relation to an increase in Fas expression at the cell surface. Taken together, these results reveal the role of Fas receptor in the lymphopenia observed in patients treated with imatinib, with potential deleterious consequences on antileukemic responses against this immunogenic hematological malignancy.


Asunto(s)
Antineoplásicos/efectos adversos , Apoptosis/efectos de los fármacos , Proteína Ligando Fas/inmunología , Leucemia Mielógena Crónica BCR-ABL Positiva/inmunología , Piperazinas/efectos adversos , Pirimidinas/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Apoptosis/inmunología , Benzamidas , Separación Celular , Femenino , Citometría de Flujo , Humanos , Mesilato de Imatinib , Activación de Linfocitos/efectos de los fármacos , Activación de Linfocitos/inmunología , Linfopenia/inducido químicamente , Masculino , Persona de Mediana Edad , Receptor fas/inmunología
8.
Oncotarget ; 2(11): 874-85, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22141136

RESUMEN

AXL is a receptor tyrosine kinase of the TAM family, the function of which is poorly understood. We previously identified AXL overexpression in Imatinib (IM)-resistant CML cell lines and patients. The present study was conducted to investigate the role of AXL and the mechanisms underlying AXL overexpression in Tyrosine Kinase Inhibitor (TKI)-resistant CML cells. We present evidence that high AXL expression level is a feature of TKI-resistant CML cells and knockdown of AXL sensitized TKI-resistant cells to IM. In addition, expression of wild-type AXL but not a dominant negative form of AXL confers IM-sensitive CML cells the capacity to resist IM effect. AXL overexpression required PKCα and ß and constitutive activation of ERK1/2. Accordingly, GF109203X a PKC inhibitor, U0126 a MEK1 inhibitor and PKCα/ß knockdown restore sensitivity to IM while PKCα or PKCß overexpression in CML cells promotes protection against IM-induced cell death. Finally, using luciferase promoter activity assays we established that AXL is regulated transcriptionally through the AP1 transcription factor. Our findings reveal an unexpected role of AXL in resistance to TKI in CML cells, identify the molecular mechanisms involved in its overexpression and support the notion that AXL is a new marker of resistance to TKI in CML.


Asunto(s)
Resistencia a Antineoplásicos/fisiología , Leucemia Mielógena Crónica BCR-ABL Positiva/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Antineoplásicos/farmacología , Apoptosis/fisiología , Benzamidas , Western Blotting , Línea Celular Tumoral , Separación Celular , Citometría de Flujo , Humanos , Mesilato de Imatinib , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Piperazinas/farmacología , Pirimidinas/farmacología , Interferencia de ARN , Transducción de Señal/fisiología , Transfección , Regulación hacia Arriba , Tirosina Quinasa del Receptor Axl
9.
Cell Cycle ; 10(23): 4138-48, 2011 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-22101270

RESUMEN

Mitotic catastrophe (MC) is induced when stressed cells enter prematurely or inappropriately into mitosis and can be caused by ionizing radiation and anticancer drugs. Foretinib is a multikinase inhibitor whose mechanism of action is incompletely understood. We investigated here the effect of Foretinib on chronic myelogenous leukemia (CML) cell lines either sensitive (IM-S) or resistant (IM-R) to the tyrosine kinase inhibitor Imatinib. Foretinib decreased viability and clonogenic potential of IM-S and IM-R CML cells as well. Foretinib-treated cells exhibited increased size, spindle assembly checkpoint anomalies and enhanced ploidy that collectively evoked mitotic catastrophe (MC). Accordingly, Foretinib-stimulated CML cells displayed decreased expression of Cdk1, Cyclin B1 and Plk1. In addition, Foretinib triggered caspase-2 activation that precedes mitochondrial membrane permeabilization. Accordingly, z-VAD-fmk and a caspase-2 siRNA abolished Foretinib-mediated cell death but failed to affect MC, indicating that Foretinib-mediated apoptosis and MC are two independent events. Anisomycin, a JNK activator, impaired Foretinib-induced MC and inhibition or knockdown of JNK phenotyped its effect on MC. Moreover, we found that Foretinib acted as a potent inhibitor of JNK. Importantly, Foretinib exhibited no or very little effect on normal peripheral blood mononuclear cells, monocytes or melanocytes cells but efficiently inhibited the clonogenic potential of CD34+ cell from CML patients. Collectively, our data show that the multikinase inhibitor Foretinib induces MC in CML cells and other cell lines via JNK-dependent inhibition of Plk1 expression and triggered apoptosis by a caspase 2-mediated mechanism. This unusual mechanism of action may have important implications for the treatment of cancer.


Asunto(s)
Anilidas/farmacología , Muerte Celular , Sistema de Señalización de MAP Quinasas , Inhibidores de Proteínas Quinasas/farmacología , Quinolinas/farmacología , Clorometilcetonas de Aminoácidos/farmacología , Anisomicina/farmacología , Antígenos CD34/metabolismo , Antineoplásicos/farmacología , Benzamidas , Proteína Quinasa CDC2/genética , Proteína Quinasa CDC2/metabolismo , Caspasa 2/genética , Caspasa 2/metabolismo , Inhibidores de Caspasas , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Tamaño de la Célula , Supervivencia Celular , Ciclina B1/genética , Ciclina B1/metabolismo , Cisteína Endopeptidasas/genética , Cisteína Endopeptidasas/metabolismo , Activación Enzimática , Pruebas de Enzimas , Humanos , Mesilato de Imatinib , Células K562/efectos de los fármacos , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/metabolismo , Puntos de Control de la Fase M del Ciclo Celular , Melanocitos/efectos de los fármacos , Melanocitos/metabolismo , Mitosis/efectos de los fármacos , Fenotipo , Piperazinas/farmacología , Ploidias , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , Pirimidinas/farmacología , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Transfección , Quinasa Tipo Polo 1
10.
Cell Cycle ; 10(14): 2339-43, 2011 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-21654192

RESUMEN

Azacitidine (AZA) is the current treatment for patients with high-risk myelodysplastic syndrome, but resistance is a common feature of AZA-treated patients. To investigate the mechanisms associated with AZA resistance in vitro, we generated AZA-resistant SKM1 myeloid cells, called hereafter AZA-R. AZA-R cells exhibit impaired mitochondrial membrane permeabilization and caspase activation in response to AZA compared to their AZA-sensitive (AZA-S) counterpart. AZA induced LC3-II accumulation and cathepsin B activity in AZA-S cells, two hallmarks of autophagy. AZA-R cells displayed increased basal autophagy but are resistant to AZA-mediated autophagy. Inhibition of autophagy using LC3 siRNA revealed that autophagy is protective in AZA-S cells and AZA-R cells in basal conditions. By contrast, AZA-R cells exhibited impaired autophagy in response to AZA. Collectively, our findings indicate that AZA promotes apoptosis and autophagy in SKM1 cells, and that AZA-R cells are resistant to both apoptosis and autophagy induced by AZA.


Asunto(s)
Antimetabolitos Antineoplásicos/farmacología , Apoptosis , Autofagia , Azacitidina/farmacología , Mitocondrias/efectos de los fármacos , Línea Celular Tumoral , Humanos , Proteínas Asociadas a Microtúbulos/antagonistas & inhibidores , Proteínas Asociadas a Microtúbulos/genética , Proteínas Asociadas a Microtúbulos/metabolismo , Síndromes Mielodisplásicos/patología , Interferencia de ARN , ARN Interferente Pequeño
12.
Mol Cancer Ther ; 10(1): 37-46, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21220490

RESUMEN

FOXO proteins are Akt-regulated transcription factors involved in the control of cell cycle, DNA repair, stress defense, apoptosis, and tumor suppression. We reported that plasmid-based overexpression of constitutively active FOXO3 in cells from chronic lymphocytic leukemia (CLL) reduced their survival, suggesting that increasing FOXO3 activity in hematologic malignancies may represent a promising therapeutic strategy. The transactivating transcription factor (TAT) protein transduction domain (PTD) derived from the HIV TAT protein was shown to efficiently deliver macromolecular cargo in various cell types. In this study, wild-type FOXO3 and FOXO3 mutated on Akt sites [FOXO3 T32A/S253A/S315A or TM (triple mutant)] were fused to the TAT-PTD. Using biochemical techniques, flow cytometry, and microscopy analysis, we found a rapid and dose-dependent cell penetration into leukemic cells of unlabeled and fluorescein isothiocyanate-labeled TAT-FOXO3 fusion proteins followed by their accumulation within nuclear and cytoplasmic compartments. Treatment with TAT-FOXO3 TM-but not wild-type TAT-FOXO3-proteins induced Jurkat and K562 leukemic cell death and affected cell viability of other hematologic malignancies including primary cells from CLL. Cell transduction with TAT-FOXO3 TM induced apoptotic cell death as shown by morphologic changes, Annexin V/7-AAD (7-amino-actinomycin D) staining, activation of effector caspases, and PARP cleavage, caspase blockade through the use of the inhibitor Z-VAD, and expression of Bim and p27(KIP1). By contrast, TAT-FOXO3 TM blocked cell proliferation of primary T cells, without affecting their viability. Together, our data show that cell penetrating TAT-FOXO3 TM fusion proteins constitute novel potential therapeutic agents in the treatment of lymphoproliferative disorders and hematologic malignancies.


Asunto(s)
Factores de Transcripción Forkhead/farmacología , Productos del Gen tat/farmacología , Leucemia/tratamiento farmacológico , Proteínas de Fusión Oncogénica/farmacología , Apoptosis/efectos de los fármacos , Procesos de Crecimiento Celular/efectos de los fármacos , Línea Celular Tumoral , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/biosíntesis , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/inmunología , Relación Dosis-Respuesta a Droga , Fluoresceína-5-Isotiocianato/farmacocinética , Proteína Forkhead Box O3 , Factores de Transcripción Forkhead/genética , Factores de Transcripción Forkhead/farmacocinética , Productos del Gen tat/genética , Productos del Gen tat/farmacocinética , Humanos , Proteínas I-kappa B/biosíntesis , Proteínas I-kappa B/inmunología , Células Jurkat , Células K562 , Leucemia/genética , Leucemia/metabolismo , Leucemia/patología , Activación de Linfocitos/efectos de los fármacos , Proteína Oncogénica v-akt/metabolismo , Proteínas de Fusión Oncogénica/genética , Proteínas de Fusión Oncogénica/farmacocinética , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología , Transducción Genética , Células U937
13.
Cancer Res ; 70(23): 9659-70, 2010 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-21098700

RESUMEN

SPARC is an extracellular matrix protein that exerts pleiotropic effects on extracellular matrix organization, growth factor availability, cell adhesion, differentiation, and immunity in cancer. Chronic myelogenous leukemia (CML) cells resistant to the BCR-ABL inhibitor imatinib (IM-R cells) were found to overexpress SPARC mRNA. In this study, we show that imatinib triggers SPARC accumulation in a variety of tyrosine kinase inhibitor (TKI)-resistant CML cell lines. SPARC silencing in IM-R cells restored imatinib sensitivity, whereas enforced SPARC expression in imatinib-sensitive cells promoted viability as well as protection against imatinib-mediated apoptosis. Notably, we found that the protective effect of SPARC required intracellular retention inside cells. Accordingly, SPARC was not secreted into the culture medium of IM-R cells. Increased SPARC expression was intimately linked to persistent activation of the Fyn/ERK kinase signaling axis. Pharmacologic inhibition of this pathway or siRNA-mediated knockdown of Fyn kinase resensitized IM-R cells to imatinib. In support of our findings, increased levels of SPARC mRNA were documented in blood cells from CML patients after 1 year of imatinib therapy compared with initial diagnosis. Taken together, our results highlight an important role for the Fyn/ERK signaling pathway in imatinib-resistant cells that is driven by accumulation of intracellular SPARC.


Asunto(s)
Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Osteonectina/metabolismo , Piperazinas/farmacología , Proteínas Proto-Oncogénicas c-fyn/metabolismo , Pirimidinas/farmacología , Transducción de Señal/efectos de los fármacos , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Benzamidas , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Resistencia a Antineoplásicos , Quinasas MAP Reguladas por Señal Extracelular/genética , Regulación Leucémica de la Expresión Génica/efectos de los fármacos , Humanos , Mesilato de Imatinib , Immunoblotting , Espacio Intracelular/metabolismo , Células K562 , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Leucemia Mielógena Crónica BCR-ABL Positiva/metabolismo , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Osteonectina/genética , Proteínas Proto-Oncogénicas c-fyn/genética , Interferencia de ARN , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células Tumorales Cultivadas , Regulación hacia Arriba
14.
Cancer Res ; 70(3): 1042-52, 2010 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-20103647

RESUMEN

Autophagy that is induced by starvation or cellular stress can enable cancer cell survival by sustaining energy homeostasis and eliminating damaged organelles and proteins. In response to stress, cancer cells have been reported to accumulate the protein p62/SQSTM1 (p62), but its role in the regulation of autophagy is controversial. Here, we report that the plant phytoalexin resveratrol (RSV) triggers autophagy in imatinib-sensitive and imatinib-resistant chronic myelogenous leukemia (CML) cells via JNK-dependent accumulation of p62. JNK inhibition or p62 knockdown prevented RSV-mediated autophagy and antileukemic effects. RSV also stimulated AMPK, thereby inhibiting the mTOR pathway. AMPK knockdown or mTOR overexpression impaired RSV-induced autophagy but not JNK activation. Lastly, p62 expression and autophagy in CD34+ progenitors from patients with CML was induced by RSV, and disrupting autophagy protected CD34+ CML cells from RSV-mediated cell death. We concluded that RSV triggered autophagic cell death in CML cells via both JNK-mediated p62 overexpression and AMPK activation. Our findings show that the JNK and AMPK pathways can cooperate to eliminate CML cells via autophagy.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Autofagia/efectos de los fármacos , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Estilbenos/farmacología , Proteínas Quinasas Activadas por AMP/genética , Proteínas Adaptadoras Transductoras de Señales/genética , Clorometilcetonas de Aminoácidos/farmacología , Antineoplásicos/farmacología , Antineoplásicos Fitogénicos/farmacología , Benzamidas , Western Blotting , Inhibidores de Caspasas , Caspasas/metabolismo , Supervivencia Celular/efectos de los fármacos , Resistencia a Antineoplásicos , Humanos , Mesilato de Imatinib , Proteínas Quinasas JNK Activadas por Mitógenos/genética , Células K562 , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Leucemia Mielógena Crónica BCR-ABL Positiva/metabolismo , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Macrólidos/farmacología , Microscopía Confocal , Microscopía Electrónica , Piperazinas/farmacología , Pirimidinas/farmacología , Interferencia de ARN , Resveratrol , Proteína Sequestosoma-1 , Células Tumorales Cultivadas , ATPasas de Translocación de Protón Vacuolares/antagonistas & inhibidores , ATPasas de Translocación de Protón Vacuolares/metabolismo
15.
PLoS One ; 4(11): e7889, 2009 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-19924252

RESUMEN

CML is an hematopoietic stem cell disease characterized by the t(9;22) (q34;q11) translocation encoding the oncoprotein p210BCR-ABL. The effect of acadesine (AICAR, 5-Aminoimidazole-4-carboxamide-1-beta-D-ribofuranoside) a compound with known antileukemic effect on B cell chronic lymphoblastic leukemia (B-CLL) was investigated in different CML cell lines. Acadesine triggered loss of cell metabolism in K562, LAMA-84 and JURL-MK1 and was also effective in killing imatinib-resistant K562 cells and Ba/F3 cells carrying the T315I-BCR-ABL mutation. The anti-leukemic effect of acadesine did not involve apoptosis but required rather induction of autophagic cell death. AMPK knock-down by Sh-RNA failed to prevent the effect of acadesine, indicating an AMPK-independent mechanism. The effect of acadesine was abrogated by GF109203X and Ro-32-0432, both inhibitor of classical and new PKCs and accordingly, acadesine triggered relocation and activation of several PKC isoforms in K562 cells. In addition, this compound exhibited a potent anti-leukemic effect in clonogenic assays of CML cells in methyl cellulose and in a xenograft model of K562 cells in nude mice. In conclusion, our work identifies an original and unexpected mechanism by which acadesine triggers autophagic cell death through PKC activation. Therefore, in addition to its promising effects in B-CLL, acadesine might also be beneficial for Imatinib-resistant CML patients.


Asunto(s)
Aminoimidazol Carboxamida/análogos & derivados , Autofagia , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Ribonucleósidos/farmacología , Proteínas Quinasas Activadas por AMP/metabolismo , Aminoimidazol Carboxamida/farmacología , Animales , Apoptosis , Línea Celular Tumoral , Proliferación Celular , Humanos , Células K562 , Ratones , Ratones Desnudos , Proteína Quinasa C/metabolismo , ARN Interferente Pequeño/metabolismo , Translocación Genética
16.
Autophagy ; 5(8): 1092-8, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19786835

RESUMEN

Autophagy is a highly conserved catabolic process for the elimination and recycling of organelles and macromolecules, characterized by the formation of double-membrane vesicles called autophagosomes. To date, the function of autophagy in cell differentiation is poorly documented. Here, we investigated the possibility that megakaryocytic differentiation of the Chronic Myelogenous Leukemia (CML) cell line K562, a process known to be accompanied by accumulation of vacuoles inside the cells, might involve autophagy. Using various complementary approaches, we show that the combination of the phorbol ester PMA and the p38(MAPK) inhibitor SB202190 (SB), which engaged a majority of K562 cells towards the megakaryocytic lineage, also triggered vacuolization and autophagy. The combination of PMA + SB appears to induce both increase in autophagic fluxes and an autophagic degradation blockage. Induction of autophagy was accompanied also by increased expression of Beclin 1 and p62/SQSTM1 and was found to precede the onset of megakaryocytic differentiation. Moreover, knockdown of LC3 and Beclin 1 by specific siRNAs impaired PMA + SB-mediated vacuolization, LC3-II accumulation and megakaryocytic differentiation, as well. To the best of our knowledge, this is the first description that induction of autophagy is involved in megakaryocytic differentiation of K562 CML cells.


Asunto(s)
Autofagia , Diferenciación Celular , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Megacariocitos/citología , Diferenciación Celular/efectos de los fármacos , Humanos , Imidazoles/farmacología , Células K562 , Megacariocitos/efectos de los fármacos , Megacariocitos/ultraestructura , Piridinas/farmacología , Acetato de Tetradecanoilforbol/farmacología , Vacuolas/efectos de los fármacos , Vacuolas/metabolismo
17.
Mol Cancer Ther ; 8(7): 1924-33, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19567819

RESUMEN

Imatinib is used to treat chronic myelogenous leukemia (CML), but resistance develops in all phases of this disease. The purpose of the present study was to identify the mode of resistance of newly derived imatinib-resistant (IM-R) and PD166326-resistant (PD-R) CML cells. IM-R and PD-R clones exhibited an increase in viability and a decrease in caspase activation in response to various doses of imatinib and PD166326, respectively, as compared with parental K562 cells. Resistance involved neither mutations in BCR-ABL nor increased BCR-ABL, MDR1 or Lyn expression, all known modes of resistance. To gain insight into the resistance mechanisms, we used pangenomic microarrays and identified 281 genes modulated in parental versus IM-R and PD-R cells. The gene signature was similar for IM-R and PD-R cells, accordingly with the cross-sensitivity observed for both inhibitors. These genes were functionally associated with pathways linked to development, cell adhesion, cell growth, and the JAK-STAT cascade. Especially relevant were the increased expression of the tyrosine kinases AXL and Fyn as well as CD44 and HMGA2. Small interfering RNA experiments and pharmacologic approaches identified FYN as a candidate for resistance to imatinib. Our findings provide a comprehensive picture of the transcriptional events associated with imatinib and PD166326 resistance and identify Fyn as a new potential target for therapeutic intervention in CML.


Asunto(s)
Resistencia a Antineoplásicos , Proteínas de Fusión bcr-abl/antagonistas & inhibidores , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Piperazinas/farmacología , Proteínas Proto-Oncogénicas c-fyn/genética , Piridinas/farmacología , Pirimidinas/farmacología , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Benzamidas , Caspasas/metabolismo , Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Citometría de Flujo , Perfilación de la Expresión Génica , Humanos , Mesilato de Imatinib , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Análisis por Micromatrices , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-fyn/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-fyn/metabolismo , ARN Interferente Pequeño/farmacología , Células Tumorales Cultivadas
18.
FASEB J ; 22(6): 1894-904, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18245170

RESUMEN

Imatinib is successfully used in the treatment of chronic myelogenous leukemia (CML), and the main mechanisms of resistance in refractory patients are now partially understood. In the present study, we investigated the mechanism of action of resveratrol in imatinib-sensitive (IM-S) and -resistant (IM-R) CML cell lines. Resveratrol induced loss of viability and apoptosis in IM-S and IM-R in a time- and dose-dependent fashion. Inhibition of cell viability was detected for concentrations of resveratrol as low as 5 microM, and the IC(50) values for viability, clonogenic assays, apoptosis, and erythroid differentiation were in the 10-25 microM range. The effect of imatinib and resveratrol was additive in IM-S but not in IM-R clones in which the resveratrol effect was already maximal. The effect of resveratrol on apoptosis was partially rescued by zVAD-fmk, suggesting a caspase-independent contribution. Resveratrol action was independent of BCR-ABL expression and phosphorylation, and in agreement was additive to BCR-ABL silencing. Finally, phytoalexin inhibited the growth of BaF3 cells expressing mutant BCR-ABL proteins found in resistant patients, including the multiresistant T315I mutation. Our findings show that resveratrol induces apoptosis, caspase-independent death, and differentiation that collectively contribute to the specific elimination of CML cells. Resveratrol should provide therapeutic benefits in IM-R patients and in other hematopoietic malignancies.


Asunto(s)
Resistencia a Antineoplásicos , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Piperazinas/farmacología , Pirimidinas/farmacología , Estilbenos/farmacología , Antineoplásicos Fitogénicos , Apoptosis/efectos de los fármacos , Benzamidas , Caspasas , Diferenciación Celular/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Humanos , Mesilato de Imatinib , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Resveratrol
19.
Haematologica ; 92(5): 627-34, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17488686

RESUMEN

BACKGROUND AND OBJECTIVES: High-dose chemotherapy with allogeneic stem cell transplantation (SCT) has proven to be a successful treatment for low-grade lymphoma (LGL), but is associated with considerable transplant-related mortality (TRM). In an effort to reduce toxic mortality while maintaining the graft-versus-leukemia effect, allogeneic SCT has been combined with a reduced-intensity conditioning (RIC) regimen. The aim of this study was to determine the outcome of patients with LGL treated with RIC allogeneic SCT. DESIGN AND METHODS: This retrospective multicenter study included 73 patients with relapsed or refractory LGL allografted after a RIC regimen between 1998 and 2005 whose data were recorded in a French registry. RESULTS: Patients received a median of three lines of therapy prior to RIC allogeneic SCT. The most widely used conditioning regimens were fludarabine + busulfan + antithymocyte globulin (n=43) and fludarabine + total body irradiation (n=21). Prior to allografting, patients were in complete response (CR; n=21), partial response (PR; n=33) or had chemoresistant disease (n=19). The median follow-up was 37 months (range, 16 to 77 months). In patients in CR, PR and chemoresistant disease, the 3-year overall survival rates were 66%, 64% and 32%, respectively, while the 3-year event-free survival rates were 66%, 52% and 32%, respectively. The 3-year cumulative incidences of TRM were 32%, 28% and 63%, respectively. The incidence of relapse was 9.6%. INTERPRETATION AND CONCLUSIONS: Although associated with significant TRM, RIC allogeneic SCT in advanced chemosensitive disease leads to long-term survival.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas/estadística & datos numéricos , Linfoma no Hodgkin/cirugía , Acondicionamiento Pretrasplante/métodos , Adulto , Anciano , Anticuerpos Monoclonales/uso terapéutico , Suero Antilinfocítico/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Busulfano/administración & dosificación , Carmustina/administración & dosificación , Terapia Combinada , Ciclofosfamida/administración & dosificación , Citarabina/administración & dosificación , Recolección de Datos , Supervivencia sin Enfermedad , Etopósido/administración & dosificación , Femenino , Francia , Enfermedad Injerto contra Huésped/epidemiología , Enfermedad Injerto contra Huésped/etiología , Efecto Injerto vs Leucemia , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Humanos , Estimación de Kaplan-Meier , Linfoma no Hodgkin/tratamiento farmacológico , Linfoma no Hodgkin/mortalidad , Masculino , Melfalán/administración & dosificación , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Inducción de Remisión , Estudios Retrospectivos , Terapia Recuperativa , Análisis de Supervivencia , Tasa de Supervivencia , Linfocitos T , Acondicionamiento Pretrasplante/efectos adversos , Trasplante Homólogo , Resultado del Tratamiento , Vidarabina/administración & dosificación , Vidarabina/análogos & derivados , Irradiación Corporal Total
20.
Clin Infect Dis ; 42(12): 1790-9, 2006 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-16705588

RESUMEN

BACKGROUND: Efavirenz (EFV) is a highly active antiretroviral drug, use of which is associated with frequent (although transient) neurosensorial adverse reactions. Whether the use of EFV is associated with the risk of depression or suicide remains controversial. METHODS: ALIZE-ANRS (Agence Nationale de Recherches sur le SIDA et les Hepatites Virales) 099 was a 48-week randomized trial involving virologically suppressed, human immunodeficiency virus (HIV)-infected patients that compared the maintenance of a treatment regimen that contained protease inhibitors (177 subjects) with a switch to a once-daily combination of EFV, didanosine, and emtricitabine (178 subjects). We used the trial's adverse events reporting system and a self-administered Center for Epidemiologic Studies-Depression Scale questionnaire to assess depressive disorders. Determinants were studied using a multivariate proportional hazards model adjusted for antiretroviral treatment, sex, age, HIV risk factor, history of depression, hepatic disorder, alcohol abuse, and HIV-related or non-HIV-related events. RESULTS: Thirty cases of depressive disorder (26 cases of depression and 4 suicide attempts) occurred during treatment in 27 patients (12 patients [7%] and 15 patients [8%] in the protease inhibitor-based and EFV-based treatment arms, respectively; P = .56). In the proportional hazards model, only age (hazard ratio, 1.6 per 10 years younger; 95% confidence interval, 1.0-2.6) and a history of depressive disorder (hazard ratio, 5.0; 95% confidence interval, 2.1-12.0) were associated with a risk of depressive disorders. The proportion of depressive patients (24%), as determined on the basis of the Center for Epidemiologic Studies-Depression Scale data, was stable during the follow-up period, without difference between treatment groups. Patients with a history of depressive disorder were more frequently depressed (53%) than were those without such history (22%; P = .03). CONCLUSIONS: The frequency of depressive disorders was high in this population, but the disorders were not related to EFV treatment. Younger age and a history of depression are important determinants for depression and should be considered for early detection and case management.


Asunto(s)
Fármacos Anti-VIH/efectos adversos , Trastorno Depresivo/inducido químicamente , Oxazinas/efectos adversos , Adulto , Envejecimiento , Alquinos , Benzoxazinas , Ciclopropanos , Femenino , Inhibidores de la Proteasa del VIH/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Suicidio
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