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1.
Br J Haematol ; 202(2): 379-383, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37192755

RESUMO

Autologous hematopoietic stem cell transplant (ASCT) is the standard curative treatment for patients with high-risk relapsed/refractory Hodgkin lymphoma (R/R HL). The AETHERA study showed survival gain with Brentuximab Vedotin (BV) maintenance after ASCT in BV-naive patients, which was recently confirmed in the retrospective AMAHRELIS cohort, including a majority of BV-exposed patients. However, this approach has not been compared to intensive tandem auto/auto or auto/allo transplant strategies, which were used before BV approval. Here, we matched BV maintenance (AMAHRELIS) and tandem SCT (HR2009) cohorts, and observed that BV maintenance was associated with better survival outcome in patients with HR R/R HL.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Doença de Hodgkin , Imunoconjugados , Humanos , Brentuximab Vedotin , Doença de Hodgkin/tratamento farmacológico , Estudos Retrospectivos , Imunoconjugados/uso terapêutico , Transplante de Células-Tronco , Estudos de Coortes
2.
Ann Hematol ; 102(5): 1159-1169, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36991231

RESUMO

Primary central nervous system lymphomas (PCNSLs) classically remain confined within the CNS throughout their evolution for unknown reasons. Our objective was to analyse the rare extracerebral relapses of PCNSL in a nationwide population-based study. We retrospectively selected PCNSL patients who experienced extracerebral relapse during their follow-up from the French LOC database. Of the 1968 PCNSL included in the database from 2011, 30 (1.5%, median age 71 years, median KPS 70) presented an extracerebral relapse, either pure (n = 20) or mixed (both extracerebral and in the CNS) (n = 10), with a histological confirmation in 20 cases. The median delay between initial diagnosis and systemic relapse was 15.5 months [2-121 months]. We found visceral (n = 23, 77%), including testis in 5 (28%) men and breast in 3 (27%) women, lymph node (n = 12, 40%), and peripheral nervous system (PNS) (n = 7, 23%) involvement. Twenty-seven patients were treated with chemotherapy, either with only systemic targets (n = 7) or mixed systemic and CNS targets (n = 20), 4 were consolidated by HCT-ASCT. After systemic relapse, the median progression-free survival and overall survival (OS) were 7 and 12 months, respectively. KPS > 70 and pure systemic relapses were significantly associated with higher OS. Extracerebral PCNSL relapses are rare, mainly extranodal, and frequently involve the testis, breast, and PNS. The prognosis was worse in mixed relapses. Early relapses raise the question of misdiagnosed occult extracerebral lymphoma at diagnostic workup that should systematically include a PET-CT. Paired tumour analysis at diagnosis/relapse would provide a better understanding of the underlying molecular mechanisms.


Assuntos
Neoplasias do Sistema Nervoso Central , Linfoma , Masculino , Humanos , Feminino , Idoso , Estudos Retrospectivos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Recidiva Local de Neoplasia/tratamento farmacológico , Linfoma/diagnóstico , Linfoma/epidemiologia , Linfoma/terapia , Prognóstico , Neoplasias do Sistema Nervoso Central/terapia , Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica
4.
Br J Cancer ; 106(10): 1660-7, 2012 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-22510748

RESUMO

BACKGROUND: Cancer cells are frequently addicted to deregulated oncogenic protein translation. The small molecule 4EG-I selectively inhibits the cap-dependent translation of mRNAs. As multiple myeloma is an incurable disease that requires new therapeutic approaches, we investigated whether targeting the translation initiation pathway could be a target for myeloma therapy. METHODS: Six myeloma cell lines and primary samples were included in this study. The 4EGI-1 effect was determined by AnnexinV staining and caspase activation. Modification of Bcl-2 protein expression was analysed, and the significance of modified proteins was analysed by knock-down experiments. RESULTS: We demonstrated that 4EGI-1 impaired the assembly of the eIF4F complex and decreased the expression of the eIF4E-regulated proteins in myeloma cells. Furthermore, we showed that 4EGI-1 induced strong apoptosis in five out of six myeloma cell lines. Apoptosis is associated with the activation of the intrinsic mitochondrial pathway. The 4EGI-1 triggered Noxa induction only in cells undergoing apoptosis through endoplasmic reticulum (ER) stress. Furthermore, Noxa silencing prevented myeloma cells from 4EGI-1-induced apoptosis. Finally, Noxa induction led to a disruption of Mcl-1/Bim complexes in parallel to the generation of 'Mcl-1-free Noxa'. CONCLUSION: Our results suggested that the use of inhibitors that directly target the translation initiation complex eIF4F could represent a potential novel approach for multiple myeloma therapy.


Assuntos
Apoptose/efeitos dos fármacos , Fator de Iniciação 4F em Eucariotos/antagonistas & inibidores , Mieloma Múltiplo/tratamento farmacológico , Nitrocompostos/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/fisiologia , Tiazóis/farmacologia , Proteínas Reguladoras de Apoptose/metabolismo , Proteína 11 Semelhante a Bcl-2 , Linhagem Celular Tumoral , Fator de Iniciação 4F em Eucariotos/fisiologia , Humanos , Hidrazonas , Proteínas de Membrana/metabolismo , Mieloma Múltiplo/patologia , Proteína de Sequência 1 de Leucemia de Células Mieloides , Iniciação Traducional da Cadeia Peptídica/efeitos dos fármacos , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/análise , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
5.
Dermatology ; 223(3): 200-2, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21986026

RESUMO

Primary cutaneous follicle center lymphoma (PCFCL) is the most common cutaneous B cell lymphoma. It is most often indolent and responds well to rituximab. We present a case of transient rituximab-induced edematous lesions located exclusively on tumor papules in a patient treated for PCFCL. Based on this observation and on a review of the literature, we discuss the mechanism of this edematous reaction which does not seem to be allergic. Indeed, this focal reaction observed solely during the first infusion of rituximab is more likely linked with local cytokine release induced by B cell lysis in the skin. This reaction is neither unusual nor severe and should not lead to an interruption of rituximab.


Assuntos
Anticorpos Monoclonais Murinos/efeitos adversos , Antineoplásicos/efeitos adversos , Edema/diagnóstico , Linfoma de Células B/tratamento farmacológico , Linfoma Folicular/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Acetaminofen/uso terapêutico , Adulto , Antialérgicos/uso terapêutico , Anticorpos Monoclonais Murinos/uso terapêutico , Antineoplásicos/uso terapêutico , Clorfeniramina/uso terapêutico , Quimioterapia Combinada , Edema/tratamento farmacológico , Edema/etiologia , Humanos , Masculino , Metilprednisolona/uso terapêutico , Rituximab
6.
Leukemia ; 32(3): 597-605, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28914261

RESUMO

Acute myeloid leukemia (AML) with the FLT3 internal tandem duplication (FLT3-ITD AML) accounts for 20-30% of AML cases. This subtype usually responds poorly to conventional therapies, and might become resistant to FLT3 tyrosine kinase inhibitors (TKIs) due to molecular bypass mechanisms. New therapeutic strategies focusing on resistance mechanisms are therefore urgently needed. Pim kinases are FLT3-ITD oncogenic targets that have been implicated in FLT3 TKI resistance. However, their precise biological function downstream of FLT3-ITD requires further investigation. We performed high-throughput transcriptomic and proteomic analyses in Pim2-depleted FLT3-ITD AML cells and found that Pim2 predominantly controlled apoptosis through Bax expression and mitochondria disruption. We identified ribosomal protein S6 kinase A3 (RSK2), a 90 kDa serine/threonine kinase involved in the mitogen-activated protein kinase cascade encoded by the RPS6KA3 gene, as a novel Pim2 target. Ectopic expression of an RPS6KA3 allele rescued the viability of Pim2-depleted cells, supporting the involvement of RSK2 in AML cell survival downstream of Pim2. Finally, we showed that RPS6KA3 knockdown reduced the propagation of human AML cells in vivo in mice. Our results point to RSK2 as a novel Pim2 target with translational therapeutic potential in FLT3-ITD AML.


Assuntos
Duplicação Gênica , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo , Sequências de Repetição em Tandem , Tirosina Quinase 3 Semelhante a fms/genética , Animais , Apoptose , Caspases/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Leucemia Mieloide Aguda/patologia , Camundongos , Proteínas Serina-Treonina Quinases/genética , Proteínas Proto-Oncogênicas/genética , Transcriptoma , Proteína X Associada a bcl-2/metabolismo
7.
J Visc Surg ; 154(6): 421-429, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28757383

RESUMO

Splenectomy is part of the therapeutic arsenal for benign or malignant hematological disorders that constitute the main indication for elective splenectomy. With the development of minimally invasive approaches, and in particular, laparoscopy, as well as the advent of monoclonal antibody therapy, the indications and the outcomes of splenectomy for hematologic disease have changed in recent years. Nonetheless, splenectomy has its place in hemoglobinopathies and hemolytic diseases, improves thrombocytopenia in refractory immune thrombocytopenic purpura, can reverse sequelae linked to voluminous splenomegaly secondary to myelofibrosis, or can be used for diagnostic purposes or for splenomegaly in lymphoproliferative syndromes.


Assuntos
Doenças Hematológicas/cirurgia , Laparoscopia/métodos , Esplenectomia/métodos , Esplenomegalia/cirurgia , Feminino , Doenças Hematológicas/complicações , Humanos , Masculino , Prognóstico , Índice de Gravidade de Doença , Esplenomegalia/etiologia , Esplenomegalia/patologia , Resultado do Tratamento
8.
Bone Marrow Transplant ; 52(8): 1113-1119, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28436974

RESUMO

In this retrospective multicentre study, we investigated the outcomes of elderly primary central nervous system lymphoma (PCNSL) patients (⩾65 years) who underwent high-dose chemotherapy followed by autologous stem cell transplantation (HDT-ASCT) at 11 centres between 2003 and 2016. End points included remission, progression-free survival (PFS), overall survival (OS) and treatment-related mortality. We identified 52 patients (median age 68.5 years, median Karnofsky Performance Status before HDT-ASCT 80%) who all underwent thiotepa-based HDT-ASCT. Fifteen patients (28.8%) received HDT-ASCT as first-line treatment and 37 (71.2%) received it as second or subsequent line. Remission status before HDT-ASCT was: CR 34.6%, PR 51.9%, stable disease 3.8% and progressive disease 9.6%. Following completion of HDT-ASCT, 36 patients (69.2%) achieved CR (21.2% first-line setting and 48.1% second or subsequent line setting) and 9 (17.3%) PR (5.8% first-line setting and 11.5% second or subsequent line setting). With a median follow-up of 22 months after HDT-ASCT, median PFS and OS were reached after 51.1 and 122.3 months, respectively. The 2-year PFS and OS rates were 62.0% and 70.8%, respectively. We observed two HDT-ASCT-associated deaths (3.8%). In selected elderly PCNSL patients, HDT-ASCT, using thiotepa-based conditioning regimes, is feasible and effective. Further prospective and comparative studies are warranted to further evaluate the role of HDT-ASCT in elderly PCNSL patients.


Assuntos
Neoplasias do Sistema Nervoso Central/terapia , Transplante de Células-Tronco Hematopoéticas/métodos , Tiotepa/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Alquilantes/administração & dosagem , Neoplasias do Sistema Nervoso Central/mortalidade , Terapia Combinada , Intervalo Livre de Doença , Europa (Continente) , Transplante de Células-Tronco Hematopoéticas/mortalidade , Humanos , Indução de Remissão , Estudos Retrospectivos , Análise de Sobrevida , Condicionamento Pré-Transplante/métodos , Condicionamento Pré-Transplante/mortalidade , Transplante Autólogo
9.
Leukemia ; 31(11): 2326-2335, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28280275

RESUMO

Alterations in metabolic activities are cancer hallmarks that offer a wide range of new therapeutic opportunities. Here we decipher the interplay between mTORC1 activity and glucose metabolism in acute myeloid leukemia (AML). We show that mTORC1 signaling that is constantly overactivated in AML cells promotes glycolysis and leads to glucose addiction. The level of mTORC1 activity determines the sensitivity of AML cells to glycolysis inhibition as switch-off mTORC1 activity leads to glucose-independent cell survival that is sustained by an increase in mitochondrial oxidative phosphorylation. Metabolic analysis identified the pentose phosphate pathway (PPP) as an important pro-survival pathway for glucose metabolism in AML cells with high mTORC1 activity and provided a clear rational for targeting glucose-6-phosphate dehydrogenase (G6PD) in AML. Indeed, our analysis of the cancer genome atlas AML database pinpointed G6PD as a new biomarker in AML, as its overexpression correlated with an adverse prognosis in this cohort. Targeting the PPP using the G6PD inhibitor 6-aminonicotinamide induces in vitro and in vivo cytotoxicity against AML cells and synergistically sensitizes leukemic cells to chemotherapy. Our results demonstrate that high mTORC1 activity creates a specific vulnerability to G6PD inhibition that may work as a new AML therapy.


Assuntos
Glucosefosfato Desidrogenase/antagonistas & inibidores , Leucemia Mieloide Aguda/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Glucose/metabolismo , Glicólise , Humanos , Leucemia Mieloide Aguda/enzimologia , Leucemia Mieloide Aguda/patologia , Fosforilação Oxidativa
10.
Leukemia ; 19(10): 1831-4, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16121217

RESUMO

Fludarabine (FDR) therapy gives a response rate of about 30% in previously treated patients with Waldenström's macroglobulinemia (WM). The combination of FDR and cyclophosphamide (Cy) has been shown to be effective in chronic lymphoproliferative disorders. We administered the combination of FDR (30 mg/m2 i.v. D1-D3) and Cy (300 mg/m2 i.v. D1-D3) to 49 patients. Median age was 64 years. The median hemoglobin, albumin, beta 2 microglobulin and immunoglobulin M (IgM) levels were 9.9 g/100 ml, 39.6 g/l, 3 mg/l and 24.7 g/l, respectively. In all, 14 patients (29%) had not previously been treated. FDR/Cy was administered every 4 weeks for a median of four cycles. In all, 38 patients (77.6%) had partial responses, nine had stable disease and two had progressive disease. After a median of follow-up of 25 months, six patients relapsed and two patients developed large-cell lymphoma. The median time to treatment failure was 27 months. The main toxicity was hematological. In all, 12 patients died, four from progression, one from large-cell lymphoma, three from infection and four from a second malignancy. Two factors negatively influenced overall and event-free survival, age >65 years and IgM <40 g/l. The FDR/Cy combination, therefore, gives a high response rate in WM, even in previously treated patients with factors of poor prognosis.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Macroglobulinemia de Waldenstrom/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Ciclofosfamida/administração & dosagem , Progressão da Doença , Feminino , Hemoglobinas/metabolismo , Humanos , Imunoglobulina M/metabolismo , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Vidarabina/administração & dosagem , Vidarabina/análogos & derivados
11.
Cancer Res ; 46(6): 2714-9, 1986 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3084076

RESUMO

The in vitro metabolism of marcellomycin by rat tissue fractions showed conversion of marcellomycin to 7-deoxypyrromycinone, bisanhydropyrromycinone, and an as yet unidentified compound by rat liver homogenate, microsomes, cytosol, and mitochondria, and purified hepatic reduced nicotinamide adenine dinucleotide phosphate-cytochrome P-450 reductase, under anaerobic conditions and in the presence of reduced nicotinamide adenine dinucleotide phosphate. All these fractions except the purified reductase subsequently induced a progressive loss of fluorescence. Mitochondria, however, were much less active than microsomes, cytosol, and homogenate in inducing this latter phenomenon. Marcellomycin was converted to 7-deoxyaglycones only partially by nuclei. No loss of fluorescence was observed with this subcellular fraction. No loss of fluorescence was observed when doxorubicin or daunorubicin were incubated under similar conditions. The appearance of a compound with distinct spectrophotometric properties was demonstrated by absorbance spectrometry. The formation of a compound with different fluorescent characteristics was excluded, as was the binding of the aglycones to subcellular components. The activity inducing the loss of fluorescence was studied in greater detail with cytosol. It predominated in the liver and required both an electron donor and anaerobic conditions. The optimal pH for the reaction was between 7.5 and 8.0. Our results suggest the existence of an enzymatic pathway capable of converting the fluorescent nucleus of marcellomycin to a nonfluorescent metabolite.


Assuntos
Antraciclinas , Antibióticos Antineoplásicos/metabolismo , Animais , Fluorescência , Concentração de Íons de Hidrogênio , Técnicas In Vitro , Masculino , Microssomos Hepáticos/metabolismo , NADPH-Ferri-Hemoproteína Redutase/análise , Naftacenos/metabolismo , Ratos , Ratos Endogâmicos , Especificidade por Substrato
12.
J Geriatr Oncol ; 6(5): 346-52, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26116168

RESUMO

INTRODUCTION: Limited data is available on the feasibility of high-dose chemotherapy followed by autologous hematopoietic stem cell transplantation (AHSCT) in elderly patients over 70 years of age with non-Hodgkin's lymphoma (NHL). MATERIALS AND METHODS: In the setting of the Société Française de Greffe de Moelle et de Thérapie Cellulaire (SFGM-TC) group, we retrospectively analyzed 81 consecutive patients with NHL over 70 years of age who received AHSCT. RESULTS: The median age at AHSCT was 72.3 years [70-80]. Patients' were diagnosed with diffuse large B-cell lymphoma (n=40), follicular lymphoma (n=16), mantle cell lymphoma (n=15), T-cell lymphoma (n=5), and other (n=5). Hematopoietic Cell Transplantation Comorbidity Index (HCT-CI) was 0 in 73% of patients. Main conditionings were BEAM (Carmustine-Etoposide-Cytarabine-Melphalan, n=61) and melphalan alone (n=14). Median delays to reach 0.5×109/L neutrophils and 20 × 10(9)/L platelets were of 12 [9-76] days and 12 [0-143] days, respectively. One hundred day and one year cumulative incidence of NRM was 5.4% and 8.5%, respectively. The main cause of death remains relapse. CONCLUSION: In conclusion, this study revealed that AHSCT seemed to be acceptable in patients over 70 years of age with NHL. Patient age is not a limiting factor if clinical condition is adequate.


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Linfoma não Hodgkin/terapia , Sociedades Médicas , Idoso , Idoso de 80 Anos ou mais , Transplante de Medula Óssea , Terapia Baseada em Transplante de Células e Tecidos , Intervalo Livre de Doença , Feminino , Seguimentos , França/epidemiologia , Humanos , Incidência , Linfoma não Hodgkin/epidemiologia , Masculino , Prevalência , Estudos Retrospectivos , Taxa de Sobrevida/tendências
13.
Cancer Chemother Pharmacol ; 14(1): 42-8, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3965159

RESUMO

In conjunction with two phase I clinical trials, we have investigated the pharmacokinetics of marcellomycin (MCM), a new class II anthracycline antibiotic, in nine patients with normal renal and hepatic functions and no third-space fluid accumulation. MCM was infused IV over 15 min at a dosage of 27.5, 40, or 50 mg/m2. Plasma and urine samples were collected up to 72 h. MCM and metabolites were assayed by thin-layer chromatography and quantified by specific fluorescence. The disappearance of total MCM-derived fluorescence from plasma followed first-order kinetics and lacked the rebound in total fluorescence that has been described for the structurally similar agent, aclacinomycin A. After 40-50 mg/m2, the peak MCM concentration in plasma was 1.67 +/- 0.61 microM; MCM disappeared from plasma in a triexponential fashion and was undetectable by 48 h after infusion. The area under the plasma concentration-time plot (AUC), including the infusion time, was 1.11 +/- 0.39 microM X h; plasma clearance of MCM was 1.50 +/- 0.88 l/min/m2. Five other fluorescent compounds were consistently observed in plasma. M2 was a contaminant present in the parent drug. P1 and P2 were conjugates of MCM and M2, respectively. G1 and G2 were aglycones. The peak concentrations of the metabolites were 25% or less or the peak concentration for MCM, but their persistence resulted in higher AUCs than that for MCM. For the dosage of 27.5 mg/m2, fewer data were available; but the pharmacokinetics of MCM and metabolites appeared to be similar to that at higher dosage. Urinary excretion of total fluorescence amounted to 8.0% +/- 1.6% of the total dose at 40-50 mg/m2, and to 7.0% +/- 2.3% at 27.5 mg/m2. No correlation was detected among the various pharmacokinetic parameters and toxicities encountered in these patients.


Assuntos
Antraciclinas , Antibióticos Antineoplásicos/metabolismo , Adulto , Idoso , Feminino , Fluorescência , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , Naftacenos/efeitos adversos , Naftacenos/metabolismo
14.
Cancer Chemother Pharmacol ; 15(2): 153-60, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3860304

RESUMO

The metabolism and tissue distribution of aclacinomycin A (ACL), marcellomycin (MCM), and musettamycin (MST), three new anthracycline antibiotics, were compared after IV administration to mice. In plasma, total MCM- and ACL-derived fluorescence declined according to first-order kinetics, whereas an initial decline followed by a rebound was observed for MST. In plasma, MCM remained the predominant compound. ACL was eliminated more quickly, and was replaced by two metabolites, the reduced glycoside M1, and an aglycone. In the case of MST, two unidentified metabolites were observed in concentrations equivalent to that of the parent drug. The three drugs were distributed widely to organs, but only ACL achieved measurable concentrations in the brain. Initially, high concentrations of all three drugs were present in the lungs, but these decreased quickly to values similar to those present in the liver and kidneys. Intermediate concentrations of the three drugs were measured in heart and skeletal muscle. Splenic concentrations of all three drugs rose progressively, reaching a maximum at 8 h after injection in the case of ACL and MST, and at 24 h after injection in the case of MCM. Concentrations of the metabolites of MCM and MST were low in all organs except liver and kidney, where the aglycones 7-deoxypyrromycinone and bisanhydropyrromycinone were seen. The metabolism of ACL was extensive. Aglycones were dominant in the liver and kidneys, whereas reduced glycosides predominated in the spleen. These observations indicate that the murine pharmacology of these three structurally similar drugs differs markedly.


Assuntos
Aclarubicina/análogos & derivados , Antraciclinas , Antibióticos Antineoplásicos/metabolismo , Animais , Antibióticos Antineoplásicos/sangue , Cromatografia Líquida de Alta Pressão , Computadores , Masculino , Camundongos , Naftacenos/sangue , Naftacenos/metabolismo , Espectrometria de Fluorescência , Distribuição Tecidual
15.
Leukemia ; 28(2): 293-301, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23748345

RESUMO

Phosphorylation by Akt on Ser 280 was reported to induce cytoplasmic retention and inactivation of CHK1 with consequent genetic instability in PTEN-/- cells. In acute myeloid leukemia cells carrying the FLT3-internal tandem duplication (ITD) mutation, we observed high rates of FLT3-ITD-dependent CHK1 Ser 280 phosphorylation. Pharmacological inhibition and RNA interference identified Pim1/2, not Akt, as effectors of this phosphorylation. Pim1 catalyzed Ser 280 phosphorylation in vitro and ectopic expression of Pim1/2-induced CHK1 phosphorylation. Ser 280 phosphorylation did not modify CHK1 localization, but facilitated its cell cycle and resistance functions in leukemic cells. FLT3, PIM or CHK1 inhibitors synergized with DNA-damaging agents to induce apoptosis, allowing cells to bypass the etoposide-induced G2/M arrest. Consistently, etoposide-induced CHK1-dependent phosphorylations of CDC25C on Ser 216 and histone H3 on Thr11 were decreased upon FLT3 inhibition. Accordingly, ectopic expression of CHK1 improved the resistance of FLT3-ITD cells and maintained histone H3 phosphorylation in response to DNA damage, whereas expression of unphosphorylated Ser 280Ala mutant did not. Finally, FLT3- and Pim-dependent phosphorylation of CHK1 on Ser 280 was confirmed in primary blasts from patients. These results identify a new pathway involved in the resistance of FLT3-ITD leukemic cells to genotoxic agents, and they constitute the first report of CHK1 Ser 280 regulation in myeloid malignancies.


Assuntos
Leucemia Mieloide Aguda/metabolismo , Proteínas Quinases/metabolismo , Proteínas Proto-Oncogênicas c-pim-1/metabolismo , Linhagem Celular Tumoral , Quinase 1 do Ponto de Checagem , Duplicação Gênica , Humanos , Espaço Intracelular/metabolismo , Leucemia Mieloide Aguda/genética , Fosforilação , Transporte Proteico , Serina/metabolismo , Transdução de Sinais , Tirosina Quinase 3 Semelhante a fms/metabolismo
17.
Leukemia ; 27(7): 1479-86, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23321953

RESUMO

The mTORC1 signaling pathway is constitutively activated in almost all acute myelogenous leukemia (AML) patients. We conducted a phase Ib trial combining RAD001 (everolimus), an allosteric inhibitor of mTORC1, and conventional chemotherapy, in AML patients under 65 years of age at first relapse (clinical trial NCT 01074086). Increasing doses of RAD001 from 10-70 mg were administrated orally on days 1 and 7 (d1 and d7) of a 3+7 daunorubicin+cytarabine conventional induction chemotherapy regimen. Twenty-eight patients were enrolled in this trial. The treatment was well tolerated with <10% toxicity, mainly involving the gastrointestinal tract and lungs. In this phase Ib trial, the RAD001 maximum tolerated dose was not reached at 70 mg. Sixty-eight percent of patients achieved CR, of which 14 received a double induction. Eight subsequently were intensified with allogeneic-stem cell transplant. Strong plasma inhibition of P-p70S6K was observed after RAD001 administration, still detectable at d7 (d7)at the 70 mg dosage. CR rates in patients with RAD001 areas under or above the curve median were 53% versus 85%. A 70 mg dose of RAD001 at d1 and d7 of an induction chemotherapy regimen for AML has acceptable toxicity and may improve treatment.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Citarabina/administração & dosagem , Daunorrubicina/administração & dosagem , Leucemia Mieloide Aguda/tratamento farmacológico , Sirolimo/análogos & derivados , Serina-Treonina Quinases TOR/antagonistas & inibidores , Adulto , Idoso , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/efeitos adversos , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Citarabina/efeitos adversos , Daunorrubicina/efeitos adversos , Everolimo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Transdução de Sinais/efeitos dos fármacos , Sirolimo/administração & dosagem , Sirolimo/efeitos adversos , Resultado do Tratamento , Adulto Jovem
20.
Leukemia ; 26(6): 1195-202, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22143671

RESUMO

The serine/threonine kinase mammalian target of rapamycin (mTOR) is crucial for cell growth and proliferation, and is constitutively activated in primary acute myeloid leukemia (AML) cells, therefore representing a major target for drug development in this disease. We show here that the specific mTOR kinase inhibitor AZD8055 blocked mTORC1 and mTORC2 signaling in AML. Particularly, AZD8055 fully inhibited multisite eIF4E-binding protein 1 phosphorylation, subsequently blocking protein translation, which was in contrast to the effects of rapamycin. In addition, the mTORC1-dependent PI3K/Akt feedback activation was fully abrogated in AZD8055-treated AML cells. Significantly, AZD8055 decreased AML blast cell proliferation and cell cycle progression, reduced the clonogenic growth of leukemic progenitors and induced caspase-dependent apoptosis in leukemic cells but not in normal immature CD34+ cells. Interestingly, AZD8055 strongly induced autophagy, which may be either protective or cell death inducing, depending on concentration. Finally, AZD8055 markedly increased the survival of AML transplanted mice through a significant reduction of tumor growth, without apparent toxicity. Our current results strongly suggest that AZD8055 should be tested in AML patients in clinical trials.


Assuntos
Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/prevenção & controle , Morfolinas/farmacologia , Proteínas/antagonistas & inibidores , Fatores de Transcrição/antagonistas & inibidores , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Western Blotting , Ciclo Celular/efeitos dos fármacos , Proteínas de Ciclo Celular , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Humanos , Técnicas Imunoenzimáticas , Imunoprecipitação , Leucemia Mieloide Aguda/mortalidade , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Camundongos Nus , Complexos Multiproteicos , Fosfatidilinositol 3-Quinases/metabolismo , Fosfoproteínas/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas/metabolismo , Taxa de Sobrevida , Serina-Treonina Quinases TOR , Fatores de Transcrição/metabolismo , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto
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