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1.
Blood ; 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38717861

RESUMO

We hypothesized that fit older patients with acute myeloid leukemia (AML) treated with decitabine (DEC) would report better health-related quality of life (HRQoL) outcomes compared to those receiving intensive chemotherapy (IC). We conducted a phase 3 randomized trial to compare DEC (10-day schedule) to IC (3+7) in older fit AML patients. HRQoL was a secondary endpoint, and it was assessed with the EORTC QLQ-C30 and the QLQ-ELD14. The following scales were a priori selected for defining the primary endpoint: physical and role functioning, fatigue, pain, and burden of illness. HRQoL was assessed at baseline, at regeneration from cycle 2, and at 6 and 12 months after randomization, and also prior to allo-HSCT and 100 days after transplantation. Overall, 606 patients underwent randomization. At 2 months, the risk of HRQoL deterioration was lower in the DEC arm than in the 3+7 arm (76% [95% CI, 69 to 82] v 88% [95% CI, 82 to 93]; odds ratio, 0.43 [95% CI, 0.24 to 0.76], P=.003). No statistically significant HRQoL differences were observed between treatment arms at the long-term evaluation combining assessments at 6 and 12 months. HRQoL deteriorations between baseline and post-allo-HSCT were observed in both arms. However, these deteriorations were not clinically meaningful in patients randomized to DEC, while this was the case for those in the 3+7 arm, in four out of the five primary HRQoL scales. Our HRQoL findings suggest that lower-intensity treatment with DEC, may be preferable to current standard IC (3+7), in fit older AML patients. ClinicalTrials.gov (NCT02172872).

2.
Lancet Haematol ; 10(11): e879-e889, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37914482

RESUMO

BACKGROUND: Many older patients with acute myeloid leukaemia die or cannot undergo allogeneic haematopoietic stem-cell transplantation (HSCT) due to toxicity caused by intensive chemotherapy. We hypothesised that replacing intensive chemotherapy with decitabine monotherapy could improve outcomes. METHODS: This open-label, randomised, controlled, phase 3 trial was conducted at 54 hospitals in nine European countries. Patients aged 60 years and older who were newly diagnosed with acute myeloid leukaemia and had not yet been treated were enrolled if they had an Eastern Cooperative Oncology Group performance status of 2 or less and were eligible for intensive chemotherapy. Patients were randomly assigned (1:1) to receive decitabine or standard chemotherapy (known as 3 + 7). For the decitabine group, decitabine (20 mg/m2) was administered for the first 10 days in the first 28-day cycle, followed by 28-day cycles consisting of 5 days or 10 days of decitabine. For the 3 + 7 group, daunorubicin (60 mg/m2) was administered over the first 3 days and cytarabine (200 mg/m2) over the first 7 days, followed by 1-3 additional chemotherapy cycles. Allogeneic HSCT was strongly encouraged. Overall survival in the intention-to-treat population was the primary endpoint. Safety was assessed in all patients who received the allocated treatment. This trial is registered at ClinicalTrials.gov, NCT02172872, and is closed to new participants. FINDINGS: Between Dec 1, 2014, and Aug 20, 2019, 606 patients were randomly assigned to the decitabine (n=303) or 3 + 7 (n=303) group. Following an interim analysis which showed futility, the IDMC recommended on May 22, 2019, that the study continued as planned considering the risks and benefits for the patients participating in the study. The cutoff date for the final analysis presented here was June 30, 2021. At a median follow-up of 4·0 years (IQR 2·9-4·8), 4-year overall survival was 26% (95% CI 21-32) in the decitabine group versus 30% (24-35) in the 3 + 7 group (hazard ratio for death 1·04 [95% CI 0·86-1·26]; p=0·68). Rates of on-protocol allogeneic HSCT were similar between groups (122 [40%] of 303 patients for decitabine and 118 [39%] of 303 patients for 3+7). Rates of grade 3-5 adverse events were 254 (84%) of 302 patients in the decitabine group and 279 (94%) of 298 patients in the 3 + 7 group. The rates of grade 3-5 infections (41% [125 of 302] vs 53% [158 of 298]), oral mucositis (2% [seven of 302] vs 10% [31 of 298]) and diarrhoea (1% [three of 302] vs 8% [24 of 298]) were lower in the decitabine group than in the 3 + 7 group. Treatment-related deaths were reported for 12% (35 of 302) of patients in the decitabine group and 14% (41 of 298) in the 3 + 7 group. INTERPRETATION: 10-day decitabine did not improve overall survival but showed a better safety profile compared with 3 + 7 chemotherapy in older patients with acute myeloid leukaemia eligible for intensive chemotherapy. Decitabine could be considered a better-tolerated and sufficiently efficacious alternative to 3 + 7 induction in fit older patients with acute myeloid leukaemia without favourable genetics. FUNDING: Janssen Pharmaceuticals.


Assuntos
Leucemia Mieloide Aguda , Humanos , Pessoa de Meia-Idade , Idoso , Decitabina/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/diagnóstico , Citarabina/uso terapêutico , Daunorrubicina/uso terapêutico , Transplante Homólogo , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
3.
J Clin Oncol ; 39(36): 4009-4019, 2021 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-34752136

RESUMO

PURPOSE: Early-onset (EO) colorectal cancer (CRC, age < 50 years) incidence is increasing. Decisions on optimal adjuvant therapy should consider treatment adherence, adverse events, and expected outcomes in a population with life expectancy longer than later-onset (LO) CRC (age ≥ 50 years). MATERIALS AND METHODS: Individual patient data from six trials in the International Duration Evaluation of Adjuvant Chemotherapy database were analyzed. Characteristics, treatment adherence, and adverse events in stage II or III EO-CRC and LO-CRC were compared. To reduce confounders of non-cancer-related deaths because of age or comorbidities, time to recurrence (3-year relapse-free rate) and cancer-specific survival (5-year cancer-specific mortality rate) were considered. RESULTS: Out of 16,349 patients, 1,564 (9.6%) had EO-CRC. Compared with LO-CRC, EO-CRC had better performance status (86% v 80%, P < .01), similar T stage (% T1-3/T4: 76/24 v 77/23, P = .97), higher N2 disease rate (24% v 22%, P < .01), more likely to complete the planned treatment duration (83.2% v 78.2%, P < .01), and received a higher treatment dose intensity, especially with 6-month regimens. Gastrointestinal toxicity was more common in EO-CRC; hematologic toxicity was more frequent in LO-CRC. Compared with LO-CRC, significantly worse cancer-specific outcomes were demonstrated especially in high-risk stage III EO-CRC: lower 3-year relapse-free rate (54% v 65%; hazard ratio [HR] 1.33; 95% CI, 1.14 to 1.55; P value < .001) and higher 5-year cancer-specific mortality rate (24% v 20%; HR 1.21; 95% CI, 1.00 to 1.47; P value < .06). In this subgroup, no difference was observed with 3 or 6 months of therapy, with equally poor disease-free survival rates (57% v 56%; HR 0.97; 95% CI, 0.73 to 1.29; P value = .85). CONCLUSION: Young age is negatively prognostic in high-risk stage III CRC and associated with significantly higher relapse rate; this is despite better treatment adherence and higher administered treatment intensity, suggesting more aggressive disease biology.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimioterapia Adjuvante/métodos , Neoplasias Colorretais/complicações , Neoplasias Colorretais/tratamento farmacológico , Fluoruracila/efeitos adversos , Fluoruracila/uso terapêutico , Oxaliplatina/efeitos adversos , Oxaliplatina/uso terapêutico , Adenocarcinoma/complicações , Adenocarcinoma/mortalidade , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias Colorretais/mortalidade , Feminino , Fluoruracila/farmacologia , Humanos , Masculino , Pessoa de Meia-Idade , Oxaliplatina/farmacologia , Prognóstico , Taxa de Sobrevida , Fatores de Tempo
4.
Front Oncol ; 9: 1320, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32083013

RESUMO

Background: Perioperative chemotherapy plus surgery is one recommended standard treatment for patients with resectable gastric and esophageal cancer. Even with a multimodality treatment more than half of patients will relapse following surgical resection. Patients who have a poor response to neoadjuvant chemotherapy and have an incomplete (R1) resection or have metastatic lymph nodes in the resection specimen (N+) are especially at risk of recurrence. Current clinical practice is to continue with the same chemotherapy in the adjuvant setting as before surgery. In the phase II randomized EORTC VESTIGE trial (NCT03443856), patients with high risk resected gastric or esophageal adenocarcinoma will be randomized to either adjuvant chemotherapy (as before surgery) or to immunotherapy with nivolumab and low dose ipilimumab (nivolumab 3 mg/kg IV Q2W plus Ipilimumab 1 mg/kg IV Q6W for 1 year). The primary endpoint of the study is disease free survival, with secondary endpoints of overall survival, safety and toxicity, and quality of life. This is an open label randomized controlled multi-center phase-2 superiority trial. Patients will be randomized in a 1:1 ratio to study arms. The trial will recruit 240 patients; recruitment commenced July 2019 and is anticipated to take 30 months. Detailed inclusion/exclusion criteria, toxicity management guidelines, and statistical plans for EORTC VESTIGE are described in the manuscript. Clinical Trial Registration: The trial is registered with www.ClinicalTrials.gov, identifier: NCT03443856.

5.
PLoS Biol ; 12(12): e1002011, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25460167

RESUMO

In eukaryotic cells, surface expression of most type I transmembrane proteins requires translation and simultaneous insertion of the precursor protein into the endoplasmic reticulum (ER) membrane for subsequent routing to the cell surface. This co-translational translocation pathway is initiated when a hydrophobic N-terminal signal peptide (SP) on the nascent protein emerges from the ribosome, binds the cytosolic signal recognition particle (SRP), and targets the ribosome-nascent chain complex to the Sec61 translocon, a universally conserved protein-conducting channel in the ER-membrane. Despite their common function in Sec61 targeting and ER translocation, SPs have diverse but unique primary sequences. Thus, drugs that recognise SPs could be exploited to inhibit translocation of specific proteins into the ER. Here, through flow cytometric analysis the small-molecule macrocycle cyclotriazadisulfonamide (CADA) is identified as a highly selective human CD4 (hCD4) down-modulator. We show that CADA inhibits CD4 biogenesis and that this is due to its ability to inhibit co-translational translocation of CD4 into the lumen of the ER, both in cells as in a cell-free in vitro translation/translocation system. The activity of CADA maps to the cleavable N-terminal SP of hCD4. Moreover, through surface plasmon resonance analysis we were able to show direct binding of CADA to the SP of hCD4 and identify this SP as the target of our drug. Furthermore, CADA locks the SP in the translocon during a post-targeting step, possibly in a folded state, and prevents the translocation of the associated protein into the ER lumen. Instead, the precursor protein is routed to the cytosol for degradation. These findings demonstrate that a synthetic, cell-permeable small-molecule can be developed as a SP-binding drug to selectively inhibit protein translocation and to reversibly regulate the expression of specific target proteins.


Assuntos
Biossíntese de Proteínas/efeitos dos fármacos , Sinais Direcionadores de Proteínas , Inibidores da Síntese de Proteínas/farmacologia , Sequência de Aminoácidos , Antígenos CD4/química , Antígenos CD4/metabolismo , Regulação para Baixo/efeitos dos fármacos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Dados de Sequência Molecular , Conformação Proteica , Transporte Proteico/efeitos dos fármacos , Sulfonamidas/química , Sulfonamidas/farmacologia
6.
Chembiochem ; 13(16): 2439-44, 2012 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-23023962

RESUMO

Thermostable bacterial polymerases like Taq, Therminator and Vent exo(-) are able to perform DNA synthesis by using modified DNA precursors, a property that is exploited in several therapeutic and biotechnological applications. Viral polymerases are also known to accept modified substrates, and this has proven crucial in the development of antiviral therapies. However, non-thermostable polymerases of bacterial origin, or engineered variants, that have similar substrate tolerance and could be used for synthetic biology purposes remain to be identified. We have identified the α subunit of Escherichia coli polymerase III (Pol III α) as a bacterial polymerase that is able to recognise and process as substrates several pyrophosphate-modified dATP analogues in place of its natural substrate dATP for template-directed DNA synthesis. A number of dATP analogues featuring a modified pyrophosphate group were able to serve as substrates during enzymatic DNA synthesis by Pol III α. Features such as the presence of potentially chelating chemical groups and the size and spatial flexibility of the chemical structure seem to be of major importance for the modified leaving group to play its role during the enzymatic reaction. In addition, we could establish that if the pyrophosphate group is altered, deoxynucleotide incorporation proceeds with an efficiency varying with the nature of the nucleobase. Our results represent a great step towards the achievement of a system of artificial DNA synthesis hosted by E. coli and involving the use of altered nucleotide precursors for nucleic acid synthesis.


Assuntos
DNA Polimerase III/metabolismo , Desoxirribonucleotídeos/química , Escherichia coli/enzimologia , DNA/biossíntese , DNA Polimerase III/química , DNA Polimerase III/isolamento & purificação , Desoxirribonucleotídeos/metabolismo , Cinética , Especificidade por Substrato
7.
Org Biomol Chem ; 10(1): 146-53, 2012 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-22069085

RESUMO

The anti-HIV activity of nucleoside analogues is highly related to their substrate specificity for cellular and viral kinase and, as triphosphate, for HIV-RT. A series of phosphoramidate d4T derivatives have been synthesized and evaluated as substrates for HIV-1 RT, and also tested for their in vitro anti-HIV activity. Compounds 2 and 4 are able to inhibit HIV-1 replication to the same extent as d4T and d4TMP in MT-4 cells as well as in CEM/0 cells and CEM/TK(-) cells. The data suggests that these phosphoramidates are hydrolysed to d4T before exerting their antiviral activity.


Assuntos
Amidas/farmacologia , Fármacos Anti-HIV/farmacologia , Ácidos Fosfóricos/farmacologia , Amidas/síntese química , Amidas/química , Fármacos Anti-HIV/síntese química , Fármacos Anti-HIV/química , Linhagem Celular , HIV-1/efeitos dos fármacos , HIV-1/fisiologia , Humanos , Testes de Sensibilidade Microbiana , Ácidos Fosfóricos/síntese química , Ácidos Fosfóricos/química , Replicação Viral/efeitos dos fármacos
8.
Chembiochem ; 11(10): 1399-403, 2010 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-20533494

RESUMO

An amino acid deoxyadenosine phosphoramidate and the corresponding phosphodiester congener have been synthesized and tested for primer extension by HIV-1 reverse transcriptase. Replacement of the phosphoramidate linkage of L-histidine-dAMP by a phosphodiester linkage was found to have a beneficial influence on the affinity of this substrate towards HIV-1 reverse transcriptase and on the velocity of the nucleotide incorporation reaction. Modifications of the nature of the P--X bond can be useful to fine-tune the substrate properties of nucleoside triphosphate analogues. Our results also demonstrate that polymerization pausing observed during the incorporation of leaving group modified dNTPs is not caused by the nature of the linkage.


Assuntos
DNA/metabolismo , Transcriptase Reversa do HIV/metabolismo , Nucleosídeos/metabolismo , Amidas/metabolismo , Biocatálise , Nucleotídeos de Desoxiadenina/metabolismo , Histidina/metabolismo , Humanos , Cinética , Ácidos Fosfóricos/metabolismo , Especificidade por Substrato
9.
Nucleic Acids Res ; 38(8): 2541-50, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20097909

RESUMO

Previous studies in our laboratory proved that certain functional groups are able to mimic the pyrophosphate moiety and act as leaving groups in the enzymatic polymerization of deoxyribonucleic acids by HIV-1 reverse transcriptase. When the potential leaving group possesses two carboxylic acid moieties linked to the nucleoside via a phosphoramidate bond, it is efficiently recognized by this error-prone enzyme, resulting in nucleotide incorporation into DNA. Here, we present a new efficient alternative leaving group, iminodiacetic acid, which displays enhanced kinetics and an enhanced elongation capacity compared to previous results obtained with amino acid deoxyadenosine phosphoramidates. Iminodiacetic acid phosphoramidate of deoxyadenosine monophosphate (IDA-dAMP) is processed by HIV-1 RT as a substrate for single nucleotide incorporation and displays a typical Michaelis-Menten kinetic profile. This novel substrate also proved to be successful in primer strand elongation of a seven-base template overhang. Modelling of this new substrate in the active site of the enzyme revealed that the interactions formed between the triphosphate moiety, magnesium ions and enzyme's residues could be different from those of the natural triphosphate substrate and is likely to involve additional amino acid residues. Preliminary testing for a potential metabolic accessibility lets us to envision its possible use in an orthogonal system for nucleic acid synthesis that would not influence or be influenced by genetic information from the outside.


Assuntos
Monofosfato de Adenosina/análogos & derivados , DNA/biossíntese , Glicina/análogos & derivados , Monofosfato de Adenosina/síntese química , Monofosfato de Adenosina/química , Monofosfato de Adenosina/metabolismo , DNA/química , Glicina/síntese química , Glicina/química , Glicina/metabolismo , Transcriptase Reversa do HIV/química , Transcriptase Reversa do HIV/metabolismo , Cinética , Modelos Moleculares
10.
Bioorg Med Chem ; 17(19): 7008-14, 2009 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-19716707

RESUMO

The replacement of the pyrophosphate moiety of 2'-deoxynucleoside triphosphates by non natural delta-dicarboxylic butyl amino acid allows incorporation of natural 2'-deoxycytidine into DNA using HIV-1 reverse transcriptase (RT) as enzyme. In contrast, the 3'-deoxycytidine analogue was not a substrate of the HIV-1 RT.


Assuntos
Amidas/química , Aminoácidos Dicarboxílicos/química , Desoxicitidina Monofosfato/análogos & derivados , Transcriptase Reversa do HIV/metabolismo , Ácidos Fosfóricos/química , Replicação do DNA , Desoxicitidina Monofosfato/metabolismo , Especificidade por Substrato
11.
Chembiochem ; 10(13): 2246-52, 2009 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-19637144

RESUMO

In previous research we demonstrated that some amino acid derivatives of deoxyadenosine 5'-O-monophosphate act as substrates for incorporation into DNA by HIV-1 reverse transcriptase while retaining the canonical base-pair selectivity for all natural bases. Thus, some amino acids mimic the pyrophosphate group in the polymerization process with this enzyme. Herein we extended this study to the evaluation of a range of potential new leaving groups with aromatic and aliphatic structures carrying one or two carboxylic acid functions. Out of this series, the isophthalic acid derivative of deoxyadenosine 5'-O-monophosphate gave single-nucleotide incorporation results similar to those obtained with the L-aspartic acid phosphoramidate of deoxyadenosine monophosphate. The glycolic acid analogue is a better substrate than the glycine congener, supporting the good leaving group properties of a phosphodiester linkage. These investigations provide new insight into the structural requirements for leaving groups that can mimic the pyrophosphate moiety of nucleoside triphosphates.


Assuntos
DNA/metabolismo , Transcriptase Reversa do HIV/metabolismo , Nucleotídeos/metabolismo , Amidas/química , Amidas/metabolismo , Nucleotídeos de Desoxiadenina/química , Nucleotídeos de Desoxiadenina/metabolismo , Humanos , Ácidos Fosfóricos/química , Ácidos Fosfóricos/metabolismo
12.
Nucleic Acids Symp Ser (Oxf) ; (52): 405-6, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18776425

RESUMO

We developed a new strategy for labeling oligonucleotides. Labels bearing an acceptor substituted azide moiety, e.g. a sulfonyl azide substituent are used during oligonucleotide synthesis instead of conventional dye phosphoramidites. Azides are well known to react with trivalent phosphor compounds to phosphor amidates and therefore they could be used instead of an oxidizer during oligonucleotide synthesis. Because N-Alkyl or N-Aryl phosphor amidates are hydrolyzed especially under acidic conditions, we used acceptor substituted azides as reactants, which results in remarkable stabilization of the corresponding amidates. This method is suitable to introduce labels at any internucleosidic linkage of an oligonucleotide and could be used for synthesis of any kind of labeled or polylabeled detection probes. Probes synthesized with these new labeling reagents are evaluated in Real Time PCR. They show the same performance like probes synthesized by conventional means. Since the labeling reagents could be easily synthesized and since excess reagent could be recycled and used for further labeling reactions, this method represents a very cost effective way for the synthesis of labeled oligonucleotides.


Assuntos
Azidas/química , Sondas de Oligonucleotídeos/síntese química , Bioquímica/métodos , Desnaturação de Ácido Nucleico , Sondas de Oligonucleotídeos/química , Reação em Cadeia da Polimerase , Ácidos Sulfínicos/química
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