Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 191
Filter
1.
Proc Natl Acad Sci U S A ; 119(9)2022 03 01.
Article in English | MEDLINE | ID: mdl-35217601

ABSTRACT

The natural auxin indole-3-acetic acid (IAA) is a key regulator of many aspects of plant growth and development. Synthetic auxin herbicides such as 2,4-D mimic the effects of IAA by inducing strong auxinic-signaling responses in plants. To determine the mechanism of 2,4-D resistance in a Sisymbrium orientale (Indian hedge mustard) weed population, we performed a transcriptome analysis of 2,4-D-resistant (R) and -susceptible (S) genotypes that revealed an in-frame 27-nucleotide deletion removing nine amino acids in the degron tail (DT) of the auxin coreceptor Aux/IAA2 (SoIAA2). The deletion allele cosegregated with 2,4-D resistance in recombinant inbred lines. Further, this deletion was also detected in several 2,4-D-resistant field populations of this species. Arabidopsis transgenic lines expressing the SoIAA2 mutant allele were resistant to 2,4-D and dicamba. The IAA2-DT deletion reduced binding to TIR1 in vitro with both natural and synthetic auxins, causing reduced association and increased dissociation rates. This mechanism of synthetic auxin herbicide resistance assigns an in planta function to the DT region of this Aux/IAA coreceptor for its role in synthetic auxin binding kinetics and reveals a potential biotechnological approach to produce synthetic auxin-resistant crops using gene-editing.


Subject(s)
2,4-Dichlorophenoxyacetic Acid , Brassicaceae/genetics , Herbicide Resistance/genetics , Insecticides , Plant Proteins/genetics , Receptors, Cell Surface/genetics , Sequence Deletion , Brassicaceae/metabolism , Dicamba , Molecular Docking Simulation , Plant Proteins/chemistry , Plant Proteins/metabolism , Protein Binding , Protein Conformation , RNA, Plant/genetics , Receptors, Cell Surface/metabolism , Sequence Analysis, RNA/methods
2.
J Biol Chem ; 299(11): 105267, 2023 11.
Article in English | MEDLINE | ID: mdl-37734554

ABSTRACT

Herbicides are small molecules that act by inhibiting specific molecular target sites within primary plant metabolic pathways resulting in catastrophic and lethal consequences. The stress induced by herbicides generates reactive oxygen species (ROS), but little is known about the nexus between each herbicide mode of action (MoA) and their respective ability to induce ROS formation. Indeed, some herbicides cause dramatic surges in ROS levels as part of their primary MoA, whereas other herbicides may generate some ROS as a secondary effect of the stress they imposed on plants. In this review, we discuss the types of ROS and their respective reactivity and describe their involvement for each known MoA based on the new Herbicide Resistance Action Committee classification.


Subject(s)
Herbicides , Herbicides/pharmacology , Herbicides/metabolism , Oxidative Stress , Plants/metabolism , Reactive Oxygen Species/metabolism , Animals
3.
Cancer ; 2024 May 28.
Article in English | MEDLINE | ID: mdl-38804723

ABSTRACT

BACKGROUND: Ponatinib is a third-generation BCR::ABL1 tyrosine kinase inhibitor (TKI) with robust activity in Philadelphia chromosome-positive leukemias. Herein, we report the long-term follow-up of the phase 2 trial of ponatinib in chronic myeloid leukemia in chronic phase. METHODS: Patients received ponatinib 30 to 45 mg/day. The primary end point was the rate of 6-month complete cytogenetic response (CCyR). The study was held in June 2014 because of the risk of cardiovascular toxicity, requiring patients to change TKI. RESULTS: Fifty-one patients were treated with ponatinib (median dose, 45 mg/day). Median age was 48 years (range, 21-75); 30 (59%) had baseline cardiovascular comorbidities. Median treatment duration was 13 months (range, 2-25). Fourteen patients (28%) discontinued ponatinib because of toxicities, 36 (71%) after the Food and Drug Administration warning/study closure, and one for noncompliance. Dasatinib was the most frequently chosen second-line TKI (n = 34; 66%). Among 46 patients evaluable at 6 months, 44 (96%) achieved CCyR, 37 (80%) major molecular response, 28 (61%) MR4, and 21 (46%) MR4.5. The cumulative 6-month rates of CCyR, major molecular response, MR4, and MR4.5 were 96%, 78%, 50%, and 36%, respectively. Durable MR4 ≥24 or ≥60 months was observed in 67% and 51% of patients, respectively. The 24-month event-free survival rate was 97%. After a median follow-up of 128 months, the 10-year overall survival rate was 90%. Eight patients (16%) had serious grade 2 to 3 cardiovascular adverse events, leading to permanent discontinuation in five (10%). CONCLUSION: Ponatinib yielded high cytogenetic and molecular responses in newly diagnosed chronic myeloid leukemia in chronic phase. Its use in the frontline setting is hindered by arterio-/vaso-occlusive and other severe toxicities.

4.
Am J Hematol ; 99(6): 1108-1118, 2024 06.
Article in English | MEDLINE | ID: mdl-38563187

ABSTRACT

We investigated using a custom NGS panel of 149 genes the mutational landscape of 64 consecutive adult patients with tyrosine kinase fusion-negative hypereosinophilia (HE)/hypereosinophilic syndrome (HES) harboring features suggestive of myeloid neoplasm. At least one mutation was reported in 50/64 (78%) patients (compared to 8/44 (18%) patients with idiopathic HE/HES/HEUS used as controls; p < .001). Thirty-five patients (54%) had at least one mutation involving the JAK-STAT pathway, including STAT5B (n = 18, among which the hotspot N642H, n = 13), JAK1 (indels in exon 13, n = 5; V658F/L, n = 2), and JAK2 (V617F, n = 6; indels in exon 13, n = 2). Other previously undescribed somatic mutations were also found in JAK2, JAK1, STAT5B, and STAT5A, including three patients who shared the same STAT5A V707fs mutation and features consistent with primary polycythemia. Nearly all JAK-STAT mutations were preceded by (or associated with) myelodysplasia-related gene mutations, especially in RNA-splicing genes or chromatin modifiers. In multivariate analysis, neurologic involvement (hazard ratio [HR] 4.95 [1.87-13.13]; p = .001), anemia (HR 5.50 [2.24-13.49]; p < .001), and the presence of a high-risk mutation (as per the molecular international prognosis scoring system: HR 6.87 [2.39-19.72]; p < .001) were independently associated with impaired overall survival. While corticosteroids were ineffective in all treated JAK-STAT-mutated patients, ruxolitinib showed positive hematological responses including in STAT5A-mutated patients. These findings emphasize the usefulness of NGS for the workup of tyrosine kinase fusion-negative HE/HES patients and support the use of JAK inhibitors in this setting. Updated classifications could consider patients with JAK-STAT mutations and eosinophilia as a new "gene mutated-entity" that could be differentiated from CEL, NOS, and idiopathic HES.


Subject(s)
Hypereosinophilic Syndrome , Mutation , STAT5 Transcription Factor , Humans , Hypereosinophilic Syndrome/genetics , Hypereosinophilic Syndrome/drug therapy , Male , Female , Middle Aged , Adult , Aged , STAT5 Transcription Factor/genetics , Janus Kinase 2/genetics , Signal Transduction , Janus Kinase 1/genetics , Aged, 80 and over , Pyrimidines/therapeutic use , Young Adult
5.
Transfus Apher Sci ; 63(3): 103899, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38402067

ABSTRACT

BACKGROUND & OBJECTIVES: The primary objective of this observational study was to perform an exhaustive description concerning patients receiving extracorporeal photopheresis (ECP) as second line treatment after steroid resistance for either acute or chronic GVHD following allo-HCT, secondary objectives were to evaluate the efficacy and long-term outcomes. STUDY DESIGN: A total of 106 patients were included, 65 (61%) males and 41 (39%) females with a median age at transplantation of 52 years (range: 20-67). ECP was initiated after transplantation either for acute GVHD [N = 25 (24%), 12 grade III and 13 grade IV] affecting skin alone (N = 5), gut alone (N = 12), gut and liver (N = 8), or chronic GVHD [N = 81 (76%), 15 (14%) limited and 66 (62%) extensive]. RESULTS: Among the 25 patients treated for acute GHVD, 67% were responders and among the 81 patients with chronic GVHD, 78% were responders. Patients with acute GVHD had a median OS of 6 months with a survival probability at 2 years of 35% [95%CI: 14-56]. Patients with chronic GVHD had a median OS of 72 months with a survival probability at 2 years of 68% [95%CI: 56-78]. There was a significant difference in terms of survival for patients responding to ECP compared to non-responders in both acute and chronic GVHD forms. Acute GVHD grade III-IV, negatively impacted on OS (HR=7.77, 95%CI: 1.7-34), p = 0.007 and on disease relapse HR= 5.88, 95%CI: 1.7-20, p = 0.005. CONCLUSION: We demonstrated that ECP is an effective treatment for GVHD in a good proportion of patients with high overall response rate.


Subject(s)
Graft vs Host Disease , Hematologic Neoplasms , Hematopoietic Stem Cell Transplantation , Photopheresis , Humans , Photopheresis/methods , Male , Female , Middle Aged , Adult , Hematopoietic Stem Cell Transplantation/methods , Aged , Hematologic Neoplasms/therapy , Chronic Disease , Transplantation, Homologous/methods , Acute Disease , Young Adult
6.
Br J Haematol ; 201(6): 1116-1124, 2023 06.
Article in English | MEDLINE | ID: mdl-37004981

ABSTRACT

Molecular recurrence (MRec) occurs in about half of all patients with chronic myeloid leukaemia (CML) who discontinue tyrosine kinase inhibitors (TKI) in sustained deep molecular response. A second TKI discontinuation has been attempted in some patients who regain the discontinuation criteria after resuming treatment. Nilotinib treatment affords faster and deeper molecular responses than imatinib as first-line therapy. We prospectively evaluated the efficacy and safety of nilotinib (300 mg twice daily) in chronic-phase CML patients who experienced MRec, after imatinib discontinuation and analysed the probability of TFR after a new attempt in patients treated for 2 years with sustained MR4.5 for at least 1 year. A total of 31 patients were included in the study between 2013 and 2018. Seven (23%) patients experienced serious adverse events after a median of 2 months of nilotinib treatment leading to discontinuation of treatment. One patient was excluded from the study for convenience. Among the 23 patients treated for 2 years with nilotinib, 22 maintained their molecular response for at least 1 year (median: 22 months) and stopped nilotinib. The TFR rates at 24 and 48 months after nilotinib discontinuation were 59.1% (95% confidence interval [CI]: 41.7%-83.7%) and 42.1% (95% CI: 25%-71%) respectively (NCT #01774630).


Subject(s)
Leukemia, Myelogenous, Chronic, BCR-ABL Positive , Protein Kinase Inhibitors , Humans , Imatinib Mesylate/adverse effects , Protein Kinase Inhibitors/adverse effects , Pyrimidines/adverse effects , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Treatment Outcome
7.
Br J Haematol ; 200(2): 175-186, 2023 01.
Article in English | MEDLINE | ID: mdl-36214090

ABSTRACT

Superior rates of deep molecular response (DMR) have been reported with the combination of tyrosine kinase inhibitors and pegylated-interferon-alpha (Peg-IFN) in patients with newly diagnosed chronic phase-chronic myeloid leukaemia (CP-CML). In this setting, this study investigated the efficacy and safety of dasatinib combined to Peg-IFN-α2b (Dasa-PegIFN, NCT01872442). A total of 79 patients (age ≤65 years) started dasatinib; 61 were eligible for Peg-IFNα-2b add-on therapy at month 3 for a maximum 21-months duration. Dasatinib was continued thereafter. The primary endpoint was the cumulative rate of molecular response 4.5 log (MR4.5 ) by 12 months. The results are reported for the 5-year duration of the study. Grade 3 neutropenia was frequent with the combination but did not induce severe infection (one of grade 3). Other adverse events were generally low grade (4% of grade 3-4) and expected. Seventy-nine per cent and 61% of patients continued the Peg-IFN until months 12 and 24, respectively. Overall, at these time points, MR4.5 rates were 25% and 38%, respectively. Thereafter, 32% and 46% of patients achieved a sustained (≥2 years) MR4.5 or MR4 , respectively. This work established the feasibility and high rates of achievement of early and sustained DMR (a prerequisite for treatment-free-remission) with dasatinib and Peg-IFNα-2b combination as initial therapy.


Subject(s)
Interferon-alpha , Leukemia, Myeloid, Chronic-Phase , Humans , Aged , Dasatinib/adverse effects , Interferon-alpha/adverse effects , Leukemia, Myeloid, Chronic-Phase/drug therapy , Polyethylene Glycols/adverse effects , Treatment Outcome
8.
Am J Hematol ; 98(11): 1762-1771, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37647134

ABSTRACT

Disease progression to accelerated/blast phase (AP/BP) in patients with chronic phase chronic myeloid leukemia (CP-CML) after treatment discontinuation (TD) has never been systematically reported in clinical trials. However, recent reports of several such cases has raised concern. To estimate the risk of AP/BP among TD-eligible patients, we conducted TFR-PRO, a cohort retro-prospective study: 870 CP-CML patients eligible for TD formed a discontinuation cohort (505 patients) and a reference one (365 patients). The primary objective was the time adjusted rate (TAR) of progression in relation to TD. Secondary endpoints included the TAR of molecular relapse, that is, loss of major molecular response (MMR). With a median follow up of 5.5 years and 5188.2 person-years available, no events occurred in the TD cohort. One event of progression was registered 55 months after the end of TD, when the patient was contributing to the reference cohort. The TAR of progression was 0.019/100 person-years (95% CI [0.003-0.138]) in the overall group; 0.0 (95% CI [0-0.163]) in the discontinuation cohort; and 0.030 (95% CI [0.004-0.215]) in the reference cohort. These differences are not statistically significant. Molecular relapses occurred in 172/505 (34.1%) patients after TD, and in 64/365 (17.5%) patients in the reference cohort, p < .0001. Similar rates were observed in TD patients in first, second or third line of treatment. CML progression in patients eligible for TD is rare and not related to TD. Fears about the risk of disease progression among patients attempting TD should be dissipated.

9.
Clin Gerontol ; 46(3): 433-445, 2023.
Article in English | MEDLINE | ID: mdl-36255289

ABSTRACT

OBJECTIVES: Gender has been identified as an important social determinant for health. This study investigates gender-specific characteristics for alcohol use (AU) among community-dwelling older adults. METHODS: This is a retrospective cross-sectional study in 1,406 community-dwelling older adults. We used standardized questionnaires to collect self-reported data on alcohol use behavior, mental health, drinking motives and resilience by using, respectively, the Alcohol Use Identification Test (AUDIT), the Brief Symptom Inventory (BSI), the Drinking Motives Questionnaire (DMQ), and the Connor-Davidson Resilience Scale (CD-RISC). Multiple linear regression was used to identify the joint contribution of those factors on AU. Hierarchical regression was used to investigate the influence of the interaction between gender and those factors on AU. RESULTS: Linear regression analyses showed different associations with AU in men and women. Hierarchical regression analyses showed that gender presented a two-way interaction effect with enhancement and anxiety variables related to AU. CONCLUSIONS: Different characteristics were found as predictors for AU among older men and women. CLINICAL IMPLICATIONS: Clinicians and health-care providers should be aware of these differences in order to provide tailored screening and intervention programs to reduce AU in older adults.


Subject(s)
Alcohol Drinking , Independent Living , Male , Humans , Female , Aged , Alcohol Drinking/epidemiology , Alcohol Drinking/psychology , Belgium/epidemiology , Cross-Sectional Studies , Retrospective Studies
10.
Haematologica ; 107(12): 2859-2869, 2022 12 01.
Article in English | MEDLINE | ID: mdl-35615931

ABSTRACT

Discontinuation of tyrosine kinase inhibitors in chronic phase chronic myeloid leukemia is feasible in clinical practice based on recently published international recommendations. Nevertheless, factors predictive of molecular recurrence have not been fully elucidated and long-term follow-up of patients enrolled in clinical studies are required in order to update knowledge on discontinuation attempts particularly in terms of the safety and durability of treatment-free remission (TFR). In the current study, we updated results from the STIM2 study in the light of the consensual criterion of molecular recurrence reported in different international recommendations. Among the 199 patients included in the perprotocol study, 108 patients lost a major molecular response. With a median follow-up of 40.8 months (5.5-111 months), the probability of treatment-free remission was 43.4% [36.3-50.4] at 5 years, 40.9% [32.8-47.3] at 7 years and 34.5% [25.6- 43.3] at 9 years. Molecular recurrence occurred between 0 to 6 months, 6 to 24 months and after 24 months in 75 patients (69%), 15 patients (14%) and 18 patients (17%), respectively. Notably, the kinetics of molecular recurrence differed significantly between these three subgroups with a median time from loss of MR4 (BCR::ABL1 IS≤0.01%) to loss of major molecular response of 1, 7 and 22 months, respectively. Predictive factors of molecular recurrence differed according to the time of occurrence of the molecular recurrence. Durations of imatinib treatment and deep molecular response as well as BCR::ABL1/ABL1 levels at cessation of tyrosine kinase inhibitor treatment, as quantified by reverse transcriptase droplet digital polymerase chain reaction, are involved in molecular recurrence occurring up to 24 months but not beyond. (ClinicalTrial. gov Identifier NCT#0134373).


Subject(s)
Leukemia, Myelogenous, Chronic, BCR-ABL Positive , Leukemia, Myeloid, Chronic-Phase , Humans , Fusion Proteins, bcr-abl/genetics , Imatinib Mesylate/therapeutic use , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics , Leukemia, Myeloid, Chronic-Phase/drug therapy , Protein Kinase Inhibitors/therapeutic use , Remission Induction , Stromal Interaction Molecule 2 , Treatment Outcome
11.
Am J Hematol ; 97(11): 1419-1426, 2022 11.
Article in English | MEDLINE | ID: mdl-36054756

ABSTRACT

Ponatinib, the only third-generation pan-BCR::ABL1 inhibitor with activity against all known BCR::ABL1 mutations including T315I, has demonstrated deep and durable responses in patients with chronic-phase chronic myeloid leukemia (CP-CML) resistant to prior second-generation (2G) TKI treatment. We present efficacy and safety outcomes from the Ponatinib Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL) and CML Evaluation (PACE) and Optimizing Ponatinib Treatment in CP-CML (OPTIC) trials for this patient population. PACE (NCT01207440) evaluated ponatinib 45 mg/day in CML patients with resistance to prior TKI or T315I. In OPTIC (NCT02467270), patients with CP-CML and resistance to ≥2 prior TKIs or T315I receiving 45 or 30 mg/day reduced their doses to 15 mg/day upon achieving ≤1% BCR::ABL1IS or received 15 mg/day continuously. Efficacy and safety outcomes from patients with CP-CML treated with ≥1 2G TKI (PACE, n = 257) and OPTIC (n = 93), 45-mg starting dose cohort, were analyzed for BCR::ABL1IS response rates, overall survival (OS), progression-free survival (PFS), and safety. By 24 months, the percentages of patients with ≤1% BCR::ABL1IS response, PFS, and OS were 46%, 68%, and 85%, respectively, in PACE and 57%, 80%, and 91%, respectively, in OPTIC. Serious treatment-emergent adverse events and serious treatment-emergent arterial occlusive event rates were 63% and 18% in PACE and 34% and 4% in OPTIC. Ponatinib shows high response rates and robust survival outcomes in patients whose disease failed prior to 2G TKIs, including patients with T315I mutation. The response-based dosing in OPTIC led to improved safety and similar efficacy outcomes compared with PACE.


Subject(s)
Imidazoles , Leukemia, Myelogenous, Chronic, BCR-ABL Positive , Leukemia, Myeloid, Chronic-Phase , Pyridazines , Clinical Trials as Topic , Drug Resistance, Neoplasm/genetics , Fusion Proteins, bcr-abl/genetics , Humans , Imidazoles/adverse effects , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics , Leukemia, Myeloid, Chronic-Phase/drug therapy , Leukemia, Myeloid, Chronic-Phase/genetics , Protein Kinase Inhibitors/adverse effects , Pyridazines/adverse effects
12.
Aging Ment Health ; 26(1): 56-64, 2022 01.
Article in English | MEDLINE | ID: mdl-33445980

ABSTRACT

INTRODUCTION: We examined the psychometric properties of the CD-RISC, including factor structure. Secondly, we examined if resilience factors moderate the association between negative affect and hazardous alcohol use. METHOD: The sample population consisted of 1,368 community-dwelling older adults. We used standardized questionnaires to collect self-reported data on alcohol use behaviour, depression and anxiety and resilience by using respectively the Alcohol Use Identification Test (AUDIT), the Brief Symptom Inventory (BSI) and the Connor-Davidson Resilience Scale (CD-RISC). RESULTS: Of the total sample (N 1.368), 80.1% reported using alcohol. The total sample and the drinking sample reported, respectively, a mean of 65.75 (SD 15.40) and 65.79 (SD 15.90) on the CD-RISC. Concerning the CD-RISC, exploratory factor analysis presents four factors of which three with a good reliability. Moderation analyses reflects that older adults with higher levels of resilient characteristics didn't report an association between negative affect and hazardous drinking. Alternatively, low resilient older adults did report an positive and significant association between negative affect and hazardous drinking. CONCLUSION: The CD-RISC appeared to be a reliable instrument, containing three factors. In our sample, high resilience moderated the association between negative affect and hazardous drinking and may serve as a buffer against hazardous drinking.


Subject(s)
Independent Living , Resilience, Psychological , Aged , Anxiety/epidemiology , Depression/epidemiology , Humans , Psychometrics , Reproducibility of Results , Surveys and Questionnaires
13.
J Biol Chem ; 295(30): 10307-10330, 2020 07 24.
Article in English | MEDLINE | ID: mdl-32430396

ABSTRACT

The widely successful use of synthetic herbicides over the past 70 years has imposed strong and widespread selection pressure, leading to the evolution of herbicide resistance in hundreds of weed species. Both target-site resistance (TSR) and nontarget-site resistance (NTSR) mechanisms have evolved to most herbicide classes. TSR often involves mutations in genes encoding the protein targets of herbicides, affecting the binding of the herbicide either at or near catalytic domains or in regions affecting access to them. Most of these mutations are nonsynonymous SNPs, but polymorphisms in more than one codon or entire codon deletions have also evolved. Some herbicides bind multiple proteins, making the evolution of TSR mechanisms more difficult. Increased amounts of protein target, by increased gene expression or by gene duplication, are an important, albeit less common, TSR mechanism. NTSR mechanisms include reduced absorption or translocation and increased sequestration or metabolic degradation. The mechanisms that can contribute to NTSR are complex and often involve genes that are members of large gene families. For example, enzymes involved in herbicide metabolism-based resistances include cytochromes P450, GSH S-transferases, glucosyl and other transferases, aryl acylamidase, and others. Both TSR and NTSR mechanisms can combine at the individual level to produce higher resistance levels. The vast array of herbicide-resistance mechanisms for generalist (NTSR) and specialist (TSR and some NTSR) adaptations that have evolved over a few decades illustrate the evolutionary resilience of weed populations to extreme selection pressures. These evolutionary processes drive herbicide and herbicide-resistant crop development and resistance management strategies.


Subject(s)
Cytochrome P-450 Enzyme System/biosynthesis , Gene Expression Regulation, Enzymologic/drug effects , Gene Expression Regulation, Plant/drug effects , Herbicide Resistance/physiology , Herbicides/pharmacology , Plant Proteins/biosynthesis , Plants/enzymology , Acclimatization , Herbicides/metabolism
14.
Br J Haematol ; 194(2): 393-402, 2021 07.
Article in English | MEDLINE | ID: mdl-34195988

ABSTRACT

Dasatinib is a second-generation BCR-ABL1 tyrosine kinase inhibitor approved for patients with chronic myeloid leukaemia (CML). Dasatinib 100 mg per day is associated with an increased risk of pleural effusion (PlEff). We randomly evaluated whether therapeutic drug monitoring (TDM) may reduce dasatinib-associated significant adverse events (AEs) by 12 months (primary endpoint). Eligible patients started dasatinib at 100 mg per day followed by dasatinib (C)min assessment. Patients considered overdosed [(C)min ≥ 3 nmol/l) were randomised between a dose-reduction strategy (TDM arm) and standard of care (control arm). Out of 287 evaluable patients, 80 patients were randomised. The primary endpoint was not met due to early haematological AEs occurring before effective dose reduction. However, a major reduction in the cumulative incidence of PlEff was observed in the TDM arm compared to the control arm (4% vs. 15%; 11% vs. 35% and 12% vs. 39% at one, two and three years, respectively (P = 0·0094)). Molecular responses were superimposable in all arms. Dasatinib TDM during treatment initiation was feasible and resulted in a significant reduction of the incidence of PlEff in the long run, without impairing molecular responses. (NCT01916785; https://clinicaltrials.gov).


Subject(s)
Antineoplastic Agents/therapeutic use , Dasatinib/therapeutic use , Drug Monitoring , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Pleural Effusion/chemically induced , Protein Kinase Inhibitors/therapeutic use , Adolescent , Adult , Aged , Aged, 80 and over , Antineoplastic Agents/administration & dosage , Antineoplastic Agents/adverse effects , Dasatinib/administration & dosage , Dasatinib/adverse effects , Dose-Response Relationship, Drug , Female , Humans , Male , Middle Aged , Pleural Effusion/prevention & control , Prospective Studies , Protein Kinase Inhibitors/administration & dosage , Protein Kinase Inhibitors/adverse effects , Treatment Outcome , Young Adult
15.
Photosynth Res ; 144(3): 361-372, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32372199

ABSTRACT

Glufosinate targets glutamine synthetase (GS), but its fast herbicidal action is triggered by reactive oxygen species (ROS). The relationship between GS inhibition and ROS accumulation was investigated in Amaranthus palmeri. Glufosinate's fast action is light-dependent with no visual symptoms or ROS formation in the dark. Inhibition of GS leads to accumulation of ammonia and metabolites of the photorespiration pathway, such as glycolate and glyoxylate, as well as depletion of other intermediates such as glycine, serine, hydroxypyruvate, and glycerate. Exogenous supply of glycolate to glufosinate-treated plants enhanced herbicidal activity and dramatically increased hydrogen peroxide accumulation (possibly from peroxisomal glycolate oxidase activity). Glufosinate affected the balance between ROS generation and scavenging. The activity of superoxide dismutase, catalase, ascorbate peroxidase, and glutathione reductase increased after glufosinate treatment in an attempt to quench the nascent ROS burst. Low doses of atrazine and dinoseb were used to investigate the sources of ROS by manipulating photosynthetic electron transport and oxygen (O2) evolution. ROS formation depended on electron flow and O2 evolution in photosystem II (PSII). Inhibition of GS disrupted photorespiration, carbon assimilation, and linear electron flow in the light reactions. Consequently, the antioxidant machinery and the water-water cycle are overwhelmed in the presence of light and glufosinate. The O2 generated by the splitting of water in PSII becomes the acceptor of electrons, generating ROS. The cascade of events leads to lipid peroxidation and forms the basis for the fast action of glufosinate.


Subject(s)
Aminobutyrates/pharmacology , Electron Transport , Glycolates/pharmacology , Herbicides/pharmacology , Photosynthesis/drug effects , Reactive Oxygen Species/metabolism , Antioxidants/metabolism , Ascorbate Peroxidases/metabolism , Catalase/metabolism , Glutamate-Ammonia Ligase/metabolism , Glycine/metabolism , Oxygen/metabolism , Photosystem II Protein Complex/metabolism , Plant Proteins/metabolism , Superoxide Dismutase/metabolism
16.
Blood ; 132(4): 393-404, 2018 07 26.
Article in English | MEDLINE | ID: mdl-29567798

ABSTRACT

Ponatinib has potent activity against native and mutant BCR-ABL1, including BCR-ABL1T315I The pivotal phase 2 Ponatinib Ph+ ALL and CML Evaluation (PACE) trial evaluated efficacy and safety of ponatinib at a starting dose of 45 mg once daily in 449 patients with chronic myeloid leukemia (CML) or Philadelphia chromosome-positive acute lymphoblastic leukemia (ALL) resistant/intolerant to dasatinib or nilotinib, or with BCR-ABL1T315I This analysis focuses on chronic-phase CML (CP-CML) patients (n = 270) with 56.8-month median follow-up. Among 267 evaluable patients, 60%, 40%, and 24% achieved major cytogenetic response (MCyR), major molecular response (MMR), and 4.5-log molecular response, respectively. The probability of maintaining MCyR for 5 years was 82% among responders. Dose reductions were implemented in October 2013 to decrease the risk of arterial occlusive events (AOEs); ≥90% of CP-CML patients who had achieved MCyR or MMR maintained response 40 months after elective dose reductions. Estimated 5-year overall survival was 73%. In CP-CML patients, the most common treatment-emergent adverse events were rash (47%), abdominal pain (46%), thrombocytopenia (46%), headache (43%), dry skin (42%), and constipation (41%). The cumulative incidence of AOEs in CP-CML patients increased over time to 31%, while the exposure-adjusted incidence of new AOEs (15.8 and 4.9 per 100 patient-years in years 1 and 5, respectively) did not increase over time. These final PACE results demonstrate ponatinib provides durable and clinically meaningful responses, irrespective of dose reductions, in this population of heavily pretreated CP-CML patients. This trial was registered at www.clinicaltrials.gov as #NCT01207440.


Subject(s)
Antineoplastic Agents/therapeutic use , Drug Resistance, Neoplasm/drug effects , Imidazoles/therapeutic use , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Philadelphia Chromosome , Pyridazines/therapeutic use , Salvage Therapy , Adult , Aged , Aged, 80 and over , Drug Resistance, Neoplasm/genetics , Female , Follow-Up Studies , Humans , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology , Male , Middle Aged , Prognosis , Safety , Survival Rate , Time Factors , Young Adult
17.
Am J Hematol ; 95(11): 1314-1323, 2020 11.
Article in English | MEDLINE | ID: mdl-32720700

ABSTRACT

FIP1L1-PDGFRA-positive myeloid neoplasm with eosinophilia (F/P+ MN-eo) is a rare disease: robust epidemiological data are lacking and reported issues are scarce, of low sample-size and limited follow-up. Imatinib mesylate (IM) is highly efficient but no predictive factor of relapse after discontinuation has yet been identified. One hundred and fifty-one patients with F/P+ MN-eo (143 males; mean age at diagnosis 49 years; mean annual incidence: 0.18 case per million population) were included in this retrospective nationwide study involving all French laboratories who perform the search of F/P fusion gene (study period: 2003-2019). The main organs involved included the spleen (44%), skin (32%), lungs (30%), heart (19%) and central nervous system (9%). Serum vitamin B12 and tryptase levels were elevated in 74/79 (94%) and 45/57 (79%) patients, respectively, and none of the 31 patients initially treated with corticosteroids achieved complete hematologic remission. All 148 (98%) IM-treated patients achieved complete hematologic and molecular (when tested, n = 84) responses. Forty-six patients eventually discontinued IM, among whom 20 (57%) relapsed. In multivariate analysis, time to IM initiation (continuous HR: 1,01 [0.99-1,03]; P = .05) and duration of IM treatment (continuous HR: 0,97 [0,95-0,99]; P = .004) were independent factors of relapse after discontinuation of IM. After a mean follow-up of 80 (56) months, the 1, 5- and 10-year overall survival rates in IM-treated patients were 99%, 95% and 84% respectively. In F/P+ MN-eo, prompt initiation of IM and longer treatment durations may prevent relapses after discontinuation of IM.


Subject(s)
Adrenal Cortex Hormones/administration & dosage , Eosinophilia , Hematologic Neoplasms , Myeloproliferative Disorders , Oncogene Proteins, Fusion , Receptor, Platelet-Derived Growth Factor alpha , mRNA Cleavage and Polyadenylation Factors , Adult , Disease-Free Survival , Eosinophilia/blood , Eosinophilia/drug therapy , Eosinophilia/genetics , Eosinophilia/mortality , Female , France/epidemiology , Hematologic Neoplasms/blood , Hematologic Neoplasms/drug therapy , Hematologic Neoplasms/genetics , Hematologic Neoplasms/mortality , Humans , Incidence , Male , Middle Aged , Myeloproliferative Disorders/blood , Myeloproliferative Disorders/drug therapy , Myeloproliferative Disorders/genetics , Myeloproliferative Disorders/mortality , Oncogene Proteins, Fusion/blood , Oncogene Proteins, Fusion/genetics , Receptor, Platelet-Derived Growth Factor alpha/blood , Receptor, Platelet-Derived Growth Factor alpha/genetics , Retrospective Studies , Survival Rate , Tryptases/blood , Vitamin B 12/blood , mRNA Cleavage and Polyadenylation Factors/blood , mRNA Cleavage and Polyadenylation Factors/genetics
18.
J Nat Prod ; 83(4): 843-851, 2020 04 24.
Article in English | MEDLINE | ID: mdl-32091209

ABSTRACT

The culture broth of Burkholderia rinojensis strain A396 is herbicidal to a number of weed species with greater observed efficacy against broadleaf than grass weeds. A portion of this activity is attributed to romidepsin, a 16-membered cyclic depsipeptide bridged by a 15-membered macrocyclic disulfide. Romidepsin, which is present in small amounts in the broth (18 to 25 µg mL-1), was isolated and purified using standard chromatographic techniques. It was established that romidepsin is a natural proherbicide that targets the activity of plant histone deacetylases (HDAC). Assays to measure plant HDAC activity were optimized by testing a number of HDAC substrates. The activity of romidepsin was greater when its macrocyclic-forming disulfide bridge was reduced to liberate a highly reactive free butenyl thiol side chain. Reduction was achieved using 200 mM tris(2-carboxyethyl)phosphine hydrochloride. A similar bioactivation of the proherbicide via reduction of the disulfide bridge of romidepsin was observed in plant-cell-free extracts. Molecular dynamic simulation of the binding of romidepsin to Arabidopsis thaliana HDAC19 indicated the reduced form of the compound could reach deep inside the catalytic domain and interact with an associated zinc atom required for enzyme activity.


Subject(s)
Biological Control Agents/chemistry , Biological Control Agents/pharmacology , Burkholderia/chemistry , Depsipeptides/chemistry , Depsipeptides/pharmacology , Herbicides/chemistry , Herbicides/pharmacology , Arabidopsis , Chromatography, High Pressure Liquid , Cucumis sativus/chemistry , Culture Media/chemistry , Disulfides , Histone Deacetylase Inhibitors/pharmacology , Molecular Dynamics Simulation , Molecular Structure , Plant Extracts/chemistry , Plant Extracts/pharmacology , Plant Leaves/chemistry , Substrate Specificity
19.
Clin J Sport Med ; 30(1): e8-e10, 2020 01.
Article in English | MEDLINE | ID: mdl-30383546

ABSTRACT

For high-level athletes, most experts consider that 1-level arthrodesis in cervical spine surgery does not prevent return to play. Nevertheless, return remains controversial in cases of 2-level fusions. We report the case of a 27-year-old professional rugby player. He had had a double cervical fusion C5C6 and C6C7 for cervical hernia and was allowed to continue rugby activities afterward. Four years after this surgery, his neck was forced in hyperflexion during a match and complete tetraplegia occurred. A computed tomography scan showed a C3C4 unilateral facet dislocation. The patient was rapidly operated on. At follow-up, 2 years after the accident, the patient remained tetraplegic with no neurologic improvement. If no definitive conclusion can be established on this first observation, many precautions must be taken before a return-to-play decision, especially in contact sports.


Subject(s)
Arthrodesis/methods , Cervical Vertebrae/injuries , Cervical Vertebrae/surgery , Football/injuries , Intervertebral Disc Displacement/surgery , Postoperative Complications , Quadriplegia/etiology , Adult , Humans , Joint Dislocations/etiology , Male , Return to Sport , Spinal Cord Injuries/etiology
20.
Pestic Biochem Physiol ; 164: 1-6, 2020 Mar.
Article in English | MEDLINE | ID: mdl-32284114

ABSTRACT

Sourgrass (Digitaria insularis) is one of the most problematic weeds in South America because glyphosate resistance is widespread across most crop production regions. Acetyl coenzyme A carboxylase (ACCase)-inhibiting herbicides have been intensively used to manage D. insularis, which substantially increased selection pressure for this class of herbicides. We confirmed resistance to ACCase herbicides in a D. insularis population from Brazil and characterized its molecular basis. Resistant plants showed high level of resistance to haloxyfop (resistance factor, RF = 613-fold), low level of resistance to pinoxaden (RF = 3.6-fold), and no resistance to clethodim. A target-site mutation, Trp2027Cys, was found in the ACCase sequence from resistant plants. A protein homology model shows that the Trp2027Cys mutation is near the herbicide-binding pocket formed between two ACCase chains, and is predicted to obstruct the access of aryloxyphenoxypropionates (FOP) herbicides to the binding site. A qPCR-based single nucleotide polymorphism genotyping method was validated to discriminate susceptible (wild-type Trp2027) and resistant (mutant Cys2027) alleles. All resistant plants were homozygous for the mutation and the assay could be used for early detection of resistance in D. insularis field samples with suspected resistance to ACCase inhibitors.


Subject(s)
Digitaria , Herbicides , Acetyl-CoA Carboxylase , Brazil , Herbicide Resistance , Mutation , Poaceae
SELECTION OF CITATIONS
SEARCH DETAIL