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1.
Blood ; 143(23): 2363-2372, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38452207

RESUMO

ABSTRACT: We previously demonstrated that a reduced-intensity chemotherapy schedule can safely replace hyper-CVAD (cyclophosphamide-vincristine-doxorubicin [Adriamycin]-dexamethasone) cycle 1 when combined with imatinib in adults with Philadelphia-positive acute lymphoblastic leukemia. In the present randomized GRAAPH-2014 trial, we used nilotinib and addressed the omission of cytarabine (Ara-C) in consolidation. The primary objective was the major molecular response (MMR) rate measured by BCR::ABL1 quantification after cycle 4 (end of consolidation). All patients were eligible for allogeneic stem cell transplant (SCT), whereas those in MMR could receive autologous SCT, followed by 2-year imatinib maintenance in both cases. After the enrollment of 156 of 265 planed patients, the data and safety monitoring board decided to hold the randomization because of an excess of relapse in the investigational arm. Among the 155 evaluable patients, 76 received Ara-C during consolidation (arm A) and 79 did not (arm B). Overall, 133 patients (85%) underwent SCT, 93 allogeneic and 40 autologous. The noninferiority end point regarding MMR was reached with 71.1% (arm A) and 77.2% (arm B) of patients reaching MMR. However, the 4-year cumulative incidence of relapse was higher in arm B compared with arm A (31.3% [95% confidence interval {CI}, 21.1%-41.9%] vs 13.2% [95% CI, 6.7%-21.9%]; P = .017), which translated to a lower relapse-free survival. With a median follow-up of 3.8 years, 4-year overall survival was 79.0% (95% CI, 70.6%-89.3%) in arm A vs 73.4% (95% CI, 63.9%-84.4%) in arm B (P = .35). Despite a noninferior rate of MMR, more relapses were observed when ARA-C was omitted without impact on survival. ClinicalTrials.gov ID, NCT02611492.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Citarabina , Leucemia-Linfoma Linfoblástico de Células Precursoras , Pirimidinas , Humanos , Citarabina/administração & dosagem , Citarabina/uso terapêutico , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Pirimidinas/uso terapêutico , Pirimidinas/administração & dosagem , Idoso , Adulto Jovem , Adolescente , Proteínas de Fusão bcr-abl/genética , Transplante de Células-Tronco Hematopoéticas
2.
Blood ; 141(2): 156-167, 2023 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-35714312

RESUMO

This open-label, randomized, phase 3 trial (NCT02577406) compared enasidenib, an oral IDH2 (isocitrate dehydrogenase 2) inhibitor, with conventional care regimens (CCRs) in patients aged ≥60 years with late-stage, mutant-IDH2 acute myeloid leukemia (AML) relapsed/refractory (R/R) to 2 or 3 prior AML-directed therapies. Patients were first preselected to a CCR (azacitidine, intermediate-dose cytarabine, low-dose cytarabine, or supportive care) and then randomized (1:1) to enasidenib 100 mg per day or CCR. The primary endpoint was overall survival (OS). Secondary endpoints included event-free survival (EFS), time to treatment failure (TTF), overall response rate (ORR), hematologic improvement (HI), and transfusion independence (TI). Overall, 319 patients were randomized to enasidenib (n = 158) or CCR (n = 161). The median age was 71 years, median (range) enasidenib exposure was 142 days (3 to 1270), and CCR was 36 days (1 to 1166). One enasidenib (0.6%) and 20 CCR (12%) patients received no randomized treatment, and 30% and 43%, respectively, received subsequent AML-directed therapies during follow-up. The median OS with enasidenib vs CCR was 6.5 vs 6.2 months (HR [hazard ratio], 0.86; P = .23); 1-year survival was 37.5% vs 26.1%. Enasidenib meaningfully improved EFS (median, 4.9 vs 2.6 months with CCR; HR, 0.68; P = .008), TTF (median, 4.9 vs 1.9 months; HR, 0.53; P < .001), ORR (40.5% vs 9.9%; P <.001), HI (42.4% vs 11.2%), and red blood cell (RBC)-TI (31.7% vs 9.3%). Enasidenib safety was consistent with prior reports. The primary study endpoint was not met, but OS was confounded by early dropout and subsequent AML-directed therapies. Enasidenib provided meaningful benefits in EFS, TTF, ORR, HI, and RBC-TI in this heavily pretreated older mutant-IDH2 R/R AML population.


Assuntos
Isocitrato Desidrogenase , Leucemia Mieloide Aguda , Idoso , Humanos , Citarabina/uso terapêutico , Isocitrato Desidrogenase/genética , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Mutação
3.
Blood ; 140(7): 756-768, 2022 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-35443031

RESUMO

DDX41 germline mutations (DDX41MutGL) are the most common genetic predisposition to myelodysplastic syndrome and acute myeloid leukemia (AML). Recent reports suggest that DDX41MutGL myeloid malignancies could be considered as a distinct entity, even if their specific presentation and outcome remain to be defined. We describe here the clinical and biological features of 191 patients with DDX41MutGL AML. Baseline characteristics and outcome of 86 of these patients, treated with intensive chemotherapy in 5 prospective Acute Leukemia French Association/French Innovative Leukemia Organization trials, were compared with those of 1604 patients with DDX41 wild-type (DDX41WT) AML, representing a prevalence of 5%. Patients with DDX41MutGL AML were mostly male (75%), in their seventh decade, and with low leukocyte count (median, 2 × 109/L), low bone marrow blast infiltration (median, 33%), normal cytogenetics (75%), and few additional somatic mutations (median, 2). A second somatic DDX41 mutation (DDX41MutSom) was found in 82% of patients, and clonal architecture inference suggested that it could be the main driver for AML progression. DDX41MutGL patients displayed higher complete remission rates (94% vs 69%; P < .0001) and longer restricted mean overall survival censored at hematopoietic stem cell transplantation (HSCT) than 2017 European LeukemiaNet intermediate/adverse (Int/Adv) DDX41WT patients (5-year difference in restricted mean survival times, 13.6 months; P < .001). Relapse rates censored at HSCT were lower at 1 year in DDX41MutGL patients (15% vs 44%) but later increased to be similar to Int/Adv DDX41WT patients at 3 years (82% vs 75%). HSCT in first complete remission was associated with prolonged relapse-free survival (hazard ratio, 0.43; 95% confidence interval, 0.21-0.88; P = .02) but not with longer overall survival (hazard ratio, 0.77; 95% confidence interval, 0.35-1.68; P = .5).


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , RNA Helicases DEAD-box/genética , Feminino , Mutação em Linhagem Germinativa , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/terapia , Masculino , Prognóstico , Estudos Prospectivos , Estudos Retrospectivos
4.
Chemistry ; 30(12): e202302731, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38227358

RESUMO

The Zr-based Metal Organic Framework (MOF) UiO-66(Zr) is widely employed owing to its good thermal and chemical stabilities. Although the long-range structure of this MOF is preserved in the presence of water during several days, little is known about the formation of defects, which cannot be detected using diffraction techniques. We apply here 17 O solid-state NMR spectroscopy at 18.8 T to investigate the reactivity of UiO-66, through the exchange of oxygen atoms between the different sites of the MOF and water. For that purpose, we have selectively enriched in 17 O isotope the carboxylate groups of UiO-66(Zr) by using it with 17 O-labeled terephthalic acid prepared using mechanochemistry. In the presence of water at 50 °C and a following dehydration at 150 °C, we observe an overall exchange of O atoms between COO- and µ3 -O2- sites. Furthermore, we demonstrate that the three distinct oxygen sites, µ3 -OH, µ3 -O2- and COO- , of UiO-66(Zr) MOF can be enriched in 17 O isotope by post-synthetic hydrothermal treatment in the presence of 17 O-enriched water. These results demonstrate the lability of Zr-O bonds and the reactivity of UiO-66(Zr) with water.

5.
Ann Hematol ; 103(3): 759-769, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38273140

RESUMO

Very few data are available about hypomethylating agent (HMA) efficiency in core binding factor acute myeloid leukemias (CBF-AML). Our main objective was to evaluate the efficacy and safety of HMA in the specific subset of CBF-AML. Here, we report the results of a multicenter retrospective French study about efficacy of HMA monotherapy, used frontline or for R/R CBF-AML. Forty-nine patients were included, and received a median of 5 courses of azacitidine (n = 46) or decitabine (n = 3). ORR was 49% for the whole cohort with a median time to response of 112 days. After a median follow-up of 72.3 months, median OS for the total cohort was 10.6 months. In multivariate analysis, hematological relapse of CBF-AML at HMA initiation was significantly associated with a poorer OS (HR: 2.13; 95%CI: 1.04-4.36; p = 0.038). Responders had a significantly improved OS (1-year OS: 75%) compared to non-responders (1-year OS: 15.3%; p < 0.0001). Hematological improvement occurred for respectively 28%, 33% and 48% for patients who were red blood cell or platelet transfusion-dependent, or who experienced grade 3/4 neutropenia at HMA initiation. Adverse events were consistent with the known safety profile of HMA. Our study highlights that HMA is a well-tolerated therapeutic option with moderate clinical activity for R/R CBF-AML and for patients who cannot handle intensive chemotherapy.


Assuntos
Azacitidina , Leucemia Mieloide Aguda , Humanos , Estudos Retrospectivos , Decitabina/uso terapêutico , Azacitidina/efeitos adversos , Leucemia Mieloide Aguda/tratamento farmacológico , Fatores de Ligação ao Core , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Resultado do Tratamento
6.
Inorg Chem ; 63(22): 10179-10193, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38729620

RESUMO

Oxalate ligands are found in many classes of materials, including energy storage materials and biominerals. Determining their local environments at the atomic scale is thus paramount to establishing the structure and properties of numerous phases. Here, we show that high-resolution 17O solid-state NMR is a valuable asset for investigating the structure of crystalline oxalate systems. First, an efficient 17O-enrichment procedure of oxalate ligands is demonstrated using mechanochemistry. Then, 17O-enriched oxalates were used for the synthesis of the biologically relevant calcium oxalate monohydrate (COM) phase, enabling the analysis of its structure and heat-induced phase transitions by high-resolution 17O NMR. Studies of the low-temperature COM form (LT-COM), using magnetic fields from 9.4 to 35.2 T, as well as 13C-17O MQ/D-RINEPT and 17O{1H} MQ/REDOR experiments, enabled the 8 inequivalent oxygen sites of the oxalates to be resolved, and tentatively assigned. The structural changes upon heat treatment of COM were also followed by high-resolution 17O NMR, providing new insight into the structures of the high-temperature form (HT-COM) and anhydrous calcium oxalate α-phase (α-COA), including the presence of structural disorder in the latter case. Overall, this work highlights the ease associated with 17O-enrichment of oxalate oxygens, and how it enables high-resolution solid-state NMR, for "NMR crystallography" investigations.

7.
Blood ; 138(7): 507-519, 2021 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-34410352

RESUMO

To design a simple and reproducible classifier predicting the overall survival (OS) of patients with acute myeloid leukemia (AML) ≥60 years of age treated with 7 + 3, we sequenced 37 genes in 471 patients from the ALFA1200 (Acute Leukemia French Association) study (median age, 68 years). Mutation patterns and OS differed between the 84 patients with poor-risk cytogenetics and the 387 patients with good (n = 13), intermediate (n = 339), or unmeasured (n = 35) cytogenetic risk. TP53 (hazards ratio [HR], 2.49; P = .0003) and KRAS (HR, 3.60; P = .001) mutations independently worsened the OS of patients with poor-risk cytogenetics. In those without poor-risk cytogenetics, NPM1 (HR, 0.57; P = .0004), FLT3 internal tandem duplications with low (HR, 1.85; P = .0005) or high (HR, 3.51; P < 10-4) allelic ratio, DNMT3A (HR, 1.86; P < 10-4), NRAS (HR, 1.54; P = .019), and ASXL1 (HR, 1.89; P = .0003) mutations independently predicted OS. Combining cytogenetic risk and mutations in these 7 genes, 39.1% of patients could be assigned to a "go-go" tier with a 2-year OS of 66.1%, 7.6% to the "no-go" group (2-year OS 2.8%), and 3.3% of to the "slow-go" group (2-year OS of 39.1%; P < 10-5). Across 3 independent validation cohorts, 31.2% to 37.7% and 11.2% to 13.5% of patients were assigned to the go-go and the no-go tiers, respectively, with significant differences in OS between tiers in all 3 trial cohorts (HDF [Hauts-de-France], n = 141, P = .003; and SAL [Study Alliance Leukemia], n = 46; AMLSG [AML Study Group], n = 223, both P < 10-5). The ALFA decision tool is a simple, robust, and discriminant prognostic model for AML patients ≥60 years of age treated with intensive chemotherapy. This model can instruct the design of trials comparing the 7 + 3 standard of care with less intensive regimens.


Assuntos
Leucemia Mieloide Aguda , Mutação , Proteínas de Neoplasias/genética , Idoso , Idoso de 80 Anos ou mais , Citogenética , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidade , Masculino , Pessoa de Meia-Idade , Taxa de Sobrevida
8.
Blood ; 137(20): 2827-2837, 2021 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-33881523

RESUMO

In patients with isocitrate dehydrogenase (IDH)-mutated acute myeloid leukemia (AML) treated by intensive chemotherapy (IC), prognostic significance of co-occurring genetic alterations and allogeneic hematopoietic stem cell transplantation (HSCT) are of particular interest with the advent of IDH1/2 mutant inhibitors. We retrospectively analyzed 319 patients with newly diagnosed AML (127 with IDH1, 135 with IDH2R140, and 57 with IDH2R172 mutations) treated with IC in 3 Acute Leukemia French Association prospective trials. In each IDH subgroup, we analyzed the prognostic impact of clinical and genetic covariates, and the role of HSCT. In patients with IDH1 mutations, the presence of NPM1 mutations was the only variable predicting improved overall survival (OS) in multivariate analysis (P < .0001). In IDH2R140-mutated AML, normal karyotype (P = .008) and NPM1 mutations (P = .01) predicted better OS. NPM1 mutations were associated with better disease-free survival (DFS; P = .0009), whereas the presence of DNMT3A mutations was associated with shorter DFS (P = .0006). In IDH2R172-mutated AML, platelet count was the only variable retained in the multivariate model for OS (P = .002). Among nonfavorable European LeukemiaNet 2010-eligible patients, 71 (36%) underwent HSCT in first complete remission (CR1) and had longer OS (P = .03) and DFS (P = .02) than nontransplanted patients. Future clinical trials testing frontline IDH inhibitors combined with IC may consider stratification on NPM1 mutational status, the primary prognostic factor in IDH1- or IDH2R140-mutated AML. HSCT improve OS of nonfavorable IDH1/2-mutated AML and should be fully integrated into the treatment strategy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Isocitrato Desidrogenase/genética , Leucemia Mieloide Aguda/genética , Proteínas de Neoplasias/genética , Mutação Puntual , Cariótipo Anormal , Idoso , Aberrações Cromossômicas , Ensaios Clínicos como Assunto/estatística & dados numéricos , DNA Metiltransferase 3A/genética , Intervalo Livre de Doença , Feminino , França/epidemiologia , Humanos , Hibridização in Situ Fluorescente , Isocitrato Desidrogenase/deficiência , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/mortalidade , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/deficiência , Nucleofosmina/genética , Modelos de Riscos Proporcionais , Estudos Prospectivos , Estudos Retrospectivos
9.
Blood ; 137(4): 524-532, 2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-32871585

RESUMO

A multistage model instructed by a large dataset (knowledge bank [KB] algorithm) has recently been developed to improve outcome predictions and tailor therapeutic decisions, including hematopoietic stem cell transplantation (HSCT) in acute myeloid leukemia (AML). We assessed the performance of the KB in guiding HSCT decisions in first complete remission (CR1) in 656 AML patients younger than 60 years from the ALFA-0702 trial (NCT00932412). KB predictions of overall survival (OS) were superior to those of European LeukemiaNet (ELN) 2017 risk stratification (C-index, 68.9 vs 63.0). Among patients reaching CR1, HSCT in CR1, as a time-dependent covariate, was detrimental in those with favorable ELN 2017 risk and those with negative NPM1 minimal residual disease (MRD; interaction tests, P = .01 and P = .02, respectively). Using KB simulations of survival at 5 years in a scenario without HSCT in CR1 (KB score), we identified, in a similar time-dependent analysis, a significant interaction between KB score and HSCT, with HSCT in CR1 being detrimental only in patients with a good prognosis based on KB simulations (KB score ≥40; interaction test, P = .01). We could finally integrate ELN 2017, NPM1 MRD, and KB scores to sort 545 CR1 patients into 278 (51.0%) HSCT candidates and 267 (49.0%) chemotherapy-only candidates. In both time-dependent and 6-month landmark analyses, HSCT significantly improved OS in HSCT candidates, whereas it significantly shortened OS in chemotherapy-only candidates. Integrating KB predictions with ELN 2017 and MRD may thus represent a promising approach to optimize HSCT timing in younger AML patients.


Assuntos
Algoritmos , Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda/terapia , Medicina de Precisão , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Tomada de Decisão Clínica , Ensaios Clínicos Fase II como Assunto/estatística & dados numéricos , Terapia Combinada , Conjuntos de Dados como Assunto , Feminino , Transplante de Células-Tronco Hematopoéticas/normas , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Estudos Multicêntricos como Assunto/estatística & dados numéricos , Neoplasia Residual , Proteínas Nucleares/genética , Nucleofosmina , Prognóstico , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Indução de Remissão , Medição de Risco , Transplante Homólogo , Adulto Jovem
10.
Haematologica ; 108(12): 3287-3297, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36891751

RESUMO

Whereas the prognosis of adult patients with Philadelphia-negative acute lymphoblastic leukemia (ALL) has greatly improved since the advent of pediatric-inspired regimens, the impact of initial central nervous system (CNS) involvement has not been formerly re-evaluated. We report here the outcome of patients with initial CNS involvement included in the pediatric-inspired prospective randomized GRAALL-2005 study. Between 2006 and 2014, 784 adult patients (aged 18-59 years) with newly diagnosed Philadelphia-negative ALL were included, of whom 55 (7%) had CNS involvement. In CNSpositive patients, overall survival was shorter (median 1.9 years vs. not reached, HR=1.8 [1.3-2.6], P<0.001). While there was no statistical difference in cumulative incidence of relapse between CNS+ and CNS- patients (HR=1.5 [0.9-2.5], P=0.11), non-relapse mortality was significantly higher in those with initial CNS disease (HR=2.1 [1.2-3.5], P=0.01). This increase in toxicity was mostly observed in patients randomized to the high-dose cyclophosphamide arm and in those who received allogeneic stem cell transplantation. Exploratory landmark analyses did not show any association between either cranial irradiation or allogeneic stem cell transplantation and outcome. Despite improved outcome in young adult ALL patients with pediatric-inspired protocols, CNS involvement is associated with a worse outcome mainly due to excess toxicity, without improved outcome with allogeneic SCT.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia-Linfoma Linfoblástico de Células Precursoras , Adulto Jovem , Humanos , Estudos Prospectivos , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Ciclofosfamida , Sistema Nervoso Central , Resultado do Tratamento
11.
Chemistry ; 29(10): e202203014, 2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36333272

RESUMO

17 O NMR spectroscopy is a powerful technique, which can provide unique information regarding the structure and reactivity of biomolecules. However, the low natural abundance of 17 O (0.04 %) generally requires working with enriched samples, which are not easily accessible. Here, we present simple, fast and cost-efficient 17 O-enrichment strategies for amino acids and peptides by using mechanochemistry. First, five unprotected amino acids were enriched under ambient conditions, consuming only microliter amounts of costly labeled water, and producing pure molecules with enrichment levels up to ∼40 %, yields ∼60-85 %, and no loss of optical purity. Subsequently, 17 O-enriched Fmoc/tBu-protected amino acids were produced on a 1 g/day scale with high enrichment levels. Lastly, a site-selective 17 O-labeling of carboxylic functions in peptide side-chains was achieved for RGD and GRGDS peptides, with ∼28 % enrichment level. For all molecules, 17 O ssNMR spectra were recorded at 14.1 T in reasonable times, making this an important step forward for future NMR studies of biomolecules.


Assuntos
Aminoácidos , Peptídeos , Aminoácidos/química , Peptídeos/química , Aminas , Espectroscopia de Ressonância Magnética , Marcação por Isótopo/métodos
12.
Ann Hematol ; 102(7): 1657-1667, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37269388

RESUMO

Population-based studies and case reports suggest that there may be an increased risk of acute leukemia associated with sickle cell disease (SCD). Following the description of a new case report, an extensive review of the literature identified 51 previously described cases. Most cases study showed myelodysplastic features confirmed, when available, by genetic markers such as chromosome 5 and/or chromosome 7 abnormalities and TP53 gene mutations. The increased risk of leukemogenesis is certainly multifactorial and related to the pathophysiologic mechanisms of the clinical manifestations of SCD. Chronic hemolysis and secondary hemochromatosis may cause increased chronic inflammation, resulting in persistent marrow stress, which could potentially compromise the genomic stability of the hematopoietic stem cells generating genomic damage and somatic mutations over the course of SCD and its treatment, resulting in a clone that led to acute myeloid leukemia.


Assuntos
Anemia Falciforme , Leucemia Mieloide Aguda , Síndromes Mielodisplásicas , Humanos , Síndromes Mielodisplásicas/genética , Leucemia Mieloide Aguda/genética , Aberrações Cromossômicas , Medula Óssea , Anemia Falciforme/complicações
13.
Faraday Discuss ; 241(0): 250-265, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-36134444

RESUMO

The possibility of enriching in 17O the water molecules within hydrated biominerals belonging to the Ca-pyrophosphate family was investigated, using liquid assisted grinding (LAG) in the presence of 17O-labelled water. Two phases with different hydration levels, namely triclinic calcium pyrophosphate dihydrate (Ca2P2O7·2H2O, denoted t-CPPD) and monoclinic calcium pyrophosphate tetrahydrate (Ca2P2O7·4H2O, denoted m-CPPT ß) were enriched in 17O using a "post-enrichment" strategy, in which the non-labelled precursors were ground under gentle milling conditions in the presence of stoichiometric quantities of 17O-enriched water (introduced here in very small volumes ∼10 µL). Using high-resolution 17O solid-state NMR (ssNMR) analyses at multiple magnetic fields, and dynamic nuclear polarisation (DNP)-enhanced 17O NMR, it was possible to show that the labelled water molecules are mainly located at the core of the crystal structures, but that they can enter the lattice in different ways, namely by dissolution/recrystallisation or by diffusion. Overall, this work sheds light on the importance of high-resolution 17O NMR to help decipher the different roles that water can play as a liquid-assisted grinding agent and as a reagent for 17O-isotopic enrichment.


Assuntos
Pirofosfato de Cálcio , Difosfatos , Cristalização , Pirofosfato de Cálcio/química , Água/química
14.
Phys Chem Chem Phys ; 25(35): 23435-23447, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37655593

RESUMO

While ball-milling is becoming one of the common tools used by synthetic chemists, an increasing number of studies highlight that it is possible to further expand the nature and number of products which can be synthesized, by heating the reaction media during mechanochemical reactions. Hence, developing set-ups enabling heating and milling to be combined is an important target, which has been looked into in both academic and industrial laboratories. Here, we report a new approach for heating up reaction media during ball-milling reactions, using induction heating (referred to as i-BM). Our set-up is attractive not only because it enables a very fast heating of the milling medium (reaching ≈80 °C in just 15 s), and that it is directly adaptable to commercially-available milling equipment, but also because it enables heating either the walls of the milling jars or the beads themselves, depending on the choice of the materials which compose them. Importantly, the possibility to heat a milling medium "from the inside" (when using for example a PMMA jar and stainless steel beads) is a unique feature compared to previously proposed systems. Through numerical simulations, we then show that it is possible to finely tune the properties of this heating system (e.g. heating rate and maximum temperature reached), by playing with the characteristics of the milling system and/or the induction heating conditions used. Lastly, examples of applications of i-BM are given, showing how it can be used to help elucidate reaction mechanisms in ball-milling, to synthesize new molecules, and to control the physical nature of milling media.

15.
Blood ; 135(8): 542-546, 2020 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-31880804

RESUMO

Acute myeloid leukemia (AML) is a highly heterogeneous disease both in terms of genetic background and response to chemotherapy. Although molecular aberrations are routinely used to stratify AML patients into prognostic subgroups when receiving standard chemotherapy, the predictive value of the genetic background and co-occurring mutations remains to be assessed when using newly approved antileukemic drugs. In the present study, we retrospectively addressed the question of the predictive value of molecular events on the benefit of the addition of gemtuzumab ozogamicin (GO) to standard front-line chemotherapy. Using the more recent European LeukemiaNet (ELN) 2017 risk classification, we confirmed that the benefit of GO was restricted to the favorable (hazard ratio [HR], 0.54, 95% confidence interval [CI], 0.30-0.98) and intermediate (HR, 0.57; 95% CI, 0.33-1.00) risk categories, whereas it did not influence the outcome of patients within the adverse risk subgroup (HR, 0.93; 95% CI, 0.61-1.43). Interestingly, the benefit of GO was significant for patients with activating signaling mutations (HR, 0.43; 95% CI, 0.28-0.65), which correlated with higher CD33 expression levels. These results suggest that molecular aberrations could be critical for future differentially tailored treatments based on integrated genetic profiles that are able to predict the benefit of GO on outcome.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Gemtuzumab/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Mutação , Idoso , Antineoplásicos Imunológicos/efeitos adversos , Gemtuzumab/efeitos adversos , Regulação Leucêmica da Expressão Gênica , Humanos , Leucemia Mieloide Aguda/genética , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Lectina 3 Semelhante a Ig de Ligação ao Ácido Siálico/genética
16.
Expert Opin Emerg Drugs ; 27(2): 169-185, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35749672

RESUMO

INTRODUCTION: Despite recent advances in the treatment of adult acute myeloid leukemia (AML), the clinical outcome of patients continues to be unsatisfactory especially among older patients, those with a high-risk profile, and in the relapsed/refractory setting. For this reason, recent clinical trials have explored novel therapeutic agents either used alone or in combination with intensive chemotherapy or low-intensity treatments. AREAS COVERED: The current paper reviews the clinical development of monoclonal antibody-based therapies in AML, their current status and phases 2 and 3 prospective trials. EXPERT OPINION: Monoclonal antibody-based therapies demonstrated efficacy and tolerability in several clinical trials, especially when used in combination either with '3 + 7' chemotherapy or with low-intensity treatments. Additional studies are needed to determine new antigens for antibody-based therapies that target leukemia stem cells and spare normal hematopoiesis. Phase 2 and 3 additional clinical trial data are needed to assess the promise of first trials, especially regarding chimeric antigen receptor T cells redirected against myeloid antigens and immune checkpoint inhibitor therapies.


Assuntos
Leucemia Mieloide Aguda , Adulto , Anticorpos Monoclonais/efeitos adversos , Ensaios Clínicos Fase II como Assunto , Humanos , Imunoterapia , Leucemia Mieloide Aguda/tratamento farmacológico , Estudos Prospectivos
17.
Cancer ; 127(23): 4421-4431, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34424530

RESUMO

BACKGROUND: Acute myeloid leukemia (AML) is fatal in elderly patients who are unfit for standard induction chemotherapy. The objective of this study was to evaluate the survival benefit of administering sapacitabine, an oral nucleoside analogue, in alternating cycles with decitabine, a low-intensity therapy, to elderly patients with newly diagnosed AML. METHODS: This randomized, open-label, phase 3 study (SEAMLESS) was conducted at 87 sites in 11 countries. Patients aged ≥70 years who were not candidates for or chose not to receive standard induction chemotherapy were randomized 1:1 to arm A (decitabine in alternating cycles with sapacitabine) received 1-hour intravenous infusions of decitabine 20 mg/m2 once daily for 5 consecutive days every 8 weeks (first cycle and subsequent odd cycles) and sapacitabine 300 mg twice daily on 3 consecutive days per week for 2 weeks every 8 weeks (second cycle and subsequent even cycles) or to control arm C who received 1-hour infusions of decitabine 20 mg/m2 once daily for 5 consecutive days every 4 weeks. Prior hypomethylating agent therapy for preexisting myelodysplastic syndromes or myeloproliferative neoplasms was an exclusion criterion. Randomization was stratified by antecedent myelodysplastic syndromes or myeloproliferative neoplasms, white blood cell count (<10 × 109 /L and ≥10 × 109 /L), and bone marrow blast percentage (≥50% vs <50%). The primary end point was overall survival (OS). Secondary end points were the rates of complete remission (CR), CR with incomplete platelet count recovery, partial remission, hematologic improvement, and stable disease along with the corresponding durations, transfusion requirements, number of hospitalized days, and 1-year survival. The trial is registered at ClinicalTrials.gov (NCT01303796). RESULTS: Between October 2011 and December 2014, 482 patients were enrolled and randomized to receive decitabine administered in alternating cycles with sapacitabine (study arm, n = 241) or decitabine monotherapy (control arm, n = 241). The median OS was 5.9 months on the study arm versus 5.7 months on the control arm (P = .8902). The CR rate was 16.6% on the study arm and 10.8% on the control arm (P = .1468). In patients with white blood cell counts <10 × 109 /L (n = 321), the median OS was higher on the study arm versus the control arm (8.0 vs 5.8 months; P = .145), as was the CR rate (21.5% vs 8.6%; P = .0017). CONCLUSIONS: The regimen of decitabine administered in alternating cycles with sapacitabine was active but did not significantly improve OS compared with decitabine monotherapy. Subgroup analyses suggest that patients with baseline white blood cell counts <10 × 109 /L might benefit from decitabine alternating with sapacitabine, with an improved CR rate and the convenience of an oral drug. These findings should be prospectively confirmed.


Assuntos
Arabinonucleosídeos , Leucemia Mieloide Aguda , Idoso , Azacitidina , Citosina/análogos & derivados , Citosina/uso terapêutico , Decitabina , Humanos , Resultado do Tratamento
19.
Chemistry ; 27(49): 12574-12588, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34131984

RESUMO

In recent years, there has been increasing interest in developing cost-efficient, fast, and user-friendly 17 O enrichment protocols to help to understand the structure and reactivity of materials by using 17 O NMR spectroscopy. Here, we show for the first time how ball milling (BM) can be used to selectively and efficiently enrich the surface of fumed silica, which is widely used at industrial scale. Short milling times (up to 15 min) allowed modulation of the enrichment level (up to ca. 5 %) without significantly changing the nature of the material. High-precision 17 O compositions were measured at different milling times by using large-geometry secondary-ion mass spectrometry (LG-SIMS). High-resolution 17 O NMR analyses (including at 35.2 T) allowed clear identification of the signals from siloxane (Si-O-Si) and silanols (Si-OH), while DNP analyses, performed by using direct 17 O polarization and indirect 17 O{1 H} CP excitation, agreed with selective labeling of the surface. Information on the distribution of Si-OH environments at the surface was obtained from 2D 1 H-17 O D-HMQC correlations. Finally, the surface-labeled silica was reacted with titania and using 17 O DNP, their common interface was probed and Si-O-Ti bonds identified.

20.
Chem Rev ; 119(12): 7529-7609, 2019 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-31059243

RESUMO

Organometallic complexes: these two words jump to the mind of the chemist and are directly associated with their utility in catalysis or as a pharmaceutical. Nevertheless, to be able to use them, it is necessary to synthesize them, and it is not always a small matter. Typically, synthesis is via solution chemistry, using a round-bottom flask and a magnetic or mechanical stirrer. This review takes stock of alternative technologies currently available in laboratories that facilitate the synthesis of such complexes. We highlight five such technologies: mechanochemistry, also known as solvent-free chemistry, uses a mortar and pestle or a ball mill; microwave activation can drastically reduce reaction times; ultrasonic activation promotes chemical reactions because of cavitation phenomena; photochemistry, which uses light radiation to initiate reactions; and continuous flow chemistry, which is increasingly used to simplify scale-up. While facilitating the synthesis of organometallic compounds, these enabling technologies also allow access to compounds that cannot be obtained in any other way. This shows how the paradigm is changing and evolving toward new technologies, without necessarily abandoning the round-bottom flask. A bright future is ahead of the organometallic chemist, thanks to these novel technologies.

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