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Caye A.,UF de Genetique Moleculaire | Beldjord K.,University Paris Diderot | Mass-Malo K.,UF de Genetique Moleculaire | Drunat S.,UF de Genetique Moleculaire | And 6 more authors.
Haematologica | Year: 2013

Deletion of the Ikaros (IKZF1) gene is an oncogenic lesion frequently associated with BCR-ABL1-positive acute lymphoblastic leukemias. It is also found in a fraction of BCR-ABL1-negative B-cell precursor acute lymphoblastic leukemias, and early studies showed it was associated with a higher risk of relapse. Therefore, screening tools are needed for evaluation in treatment protocols and possible inclusion in risk stratification. Besides monosomy 7 and large 7p abnormalities encompassing IKZF1, most IKZF1 alterations are short, intragenic deletions. Based on cohorts of patients, we mapped the microdeletion breakpoints and developed a breakpoint-specific fluorescent multiplex polymerase chain reaction that allows detection of recurrent intragenic deletions. This sensitive test could also detect IKZF1 sub-clonal deletions, whose prognostic significance should be evaluated. Moreover, we show that consensus breakpoint sequences can be used as clonal markers to monitor minimal residual disease. This paper could be useful for translational studies and in clinical management of BCP-ALL. (ClinicalTrials.gov Identifier: NCT00003728) © 2013 Ferrata Storti Foundation. Source

Herbrecht R.,Pole doncologie et dhematologie | Caillot D.,Service dHematologie Clinique | Cordonnier C.,University Paris Est Creteil | Auvrignon A.,Service dHematologie et Oncologie Pediatrique | And 9 more authors.
Journal of Antimicrobial Chemotherapy | Year: 2012

Objectives: Invasive fungal disease (IFD) remains a major concern in patients with haematological conditions. We describe diagnoses, therapeutic management and outcomes in unselected consecutive patients from haematological facilities treated for suspected or documented IFD. Methods: In this observational prospective study, children/adults with haematological conditions or haematopoietic stem cell transplantation (HSCT) were recruited upon start of non-prophylactic systemic antifungal treatment in 37 French haematological facilities (December 2007 to December 2008). IFD episodes were classified according to the 2008 EORTC/MSG criteria. Results: The cohort included 419 patients (298 adults and 121 children): 88% haematological malignancies, 28% HSCT recipients and 68% neutropenic. Patients had 423 IFD episodes: 21% mycologically documented (59% probable/proven aspergillosis, 32% proven candidiasis and 9% probable/proven other IFD) and 20% classified as possible IFD. The remaining cases were assigned to two groups: febrile neutropenia (34%) and unclassified (25%), 9% of which were classified as possible/probable/proven IFD by day 7. Treatment was thus initiated early in 59% of patients; liposomal amphotericin B and caspofungin were the most common single-agent therapies. The 12 week mortality was 18% for probable/proven aspergillosis, 15% for proven candidiasis, 10% for probable/proven other IFD, 9% for possible IFD, 3% for febrile neutropenia and 12% for unclassified episodes (log rank P = 0.016); it was dependent on age, complete remission of underlying haematological disease and mechanical ventilation. Conclusions: In this comprehensive sample of haematological patients receiving antifungal treatment, we observe a widespread resort to early therapy and a low mortality rate, including in patients with probable or proven IFD. © The Author 2012. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. Source

Ducimetiere F.,University of Lyon | Lurkin A.,University of Lyon | Ranchere-Vince D.,University of Lyon | Decouvelaere A.-V.,University of Lyon | And 12 more authors.
PLoS ONE | Year: 2011

Background: The exact overall incidence of sarcoma and sarcoma subtypes is not known. The objective of the present population-based study was to determine this incidence in a European region (Rhone-Alpes) of six million inhabitants, based on a central pathological review of the cases. Methodology/Principal Findings: From March 2005 to February 2007, pathology reports and tumor blocks were prospectively collected from the 158 pathologists of the Rhone-Alpes region. All diagnosed or suspected cases of sarcoma were collected, reviewed centrally, examined for molecular alterations and classified according to the 2002 World Health Organization classification. Of the 1287 patients screened during the study period, 748 met the criteria for inclusion in the study. The overall crude and world age-standardized incidence rates were respectively 6.2 and 4.8 per 100,000/year. Incidence rates for soft tissue, visceral and bone sarcomas were respectively 3.6, 2.0 and 0.6 per 100,000. The most frequent histological subtypes were gastrointestinal stromal tumor (18%; 1.1/100,000), unclassified sarcoma (16%; 1/100,000), liposarcoma (15%; 0.9/100,000) and leiomyosarcoma (11%; 0.7/100,000). Conclusions/Significance: The observed incidence of sarcomas was higher than expected. This study is the first detailed investigation of the crude incidence of histological and molecular subtypes of sarcomas. © 2011 Ducimetiere et al. Source

Bleyzac N.,Institute Dhematologie Et Doncologie Pediatrique | Bleyzac N.,University Claude Bernard Lyon 1 | Kebaili K.,Institute Dhematologie Et Doncologie Pediatrique | Mialou V.,Etablissement Francais du Sang Rhone Alpes | And 3 more authors.
Therapeutic Drug Monitoring | Year: 2014

BACKGROUND:: Previous reports have suggested that imatinib may increase cyclosporine exposure by CYP3A4 inhibition. However, the magnitude of this drug interaction remains unclear. At present, quantitative information about the interaction profile of imatinib is scarce. METHODS:: The authors report the effect of imatinib on cyclosporine exposure in 6 pediatric patients with Philadelphia chromosome-positive acute lymphoblastic leukemia who received cyclosporine after hematopoietic stem-cell transplantation. Dose-normalized cyclosporine trough blood concentrations (TBC) were obtained before and after imatinib introduction. In addition, a validated model-based approach was used to derive quantitative predictions of CYP3A4-mediated drug interactions with imatinib as a victim or precipitant drug. RESULTS:: The mean dose-normalized cyclosporine TBC significantly increased after 3 to 7 days of imatinib therapy. The modeling approach predicted weak-to-moderate effect of major CYP3A4 inhibitors on imatinib exposure. However, the inhibitory potency of imatinib was found to be similar to that of verapamil, suggesting significant influence of imatinib on the pharmacokinetics of drugs highly metabolized by CYP3A4. Observed increases in cyclosporine dose-normalized TBC of the 6 patients were compatible with model predictions. The observations and predictions suggest that imatinib may substantially increase cyclosporine exposure. CONCLUSIONS:: Cyclosporine dose reduction may be necessary to avoid excessive immunosuppressive effect in case of coadministration of imatinib. © 2014 by Lippincott Williams & Wilkins. Source

Touzot F.,French Institute of Health and Medical Research | Touzot F.,University of Paris Descartes | Gaillard L.,French Institute of Health and Medical Research | Gaillard L.,University of Paris Descartes | And 14 more authors.
Journal of Allergy and Clinical Immunology | Year: 2012

Background: Telomeres represent the tips of linear chromosomes. In human subjects telomere maintenance deficiency leads to dyskeratosis congenita (DC), a rare genetic disorder characterized by progressive bone marrow failure, accelerated aging, and cancer predisposition. Hoyeraal-Hreidarsson syndrome (HH) is a severe variant of DC in which an early onset of bone marrow failure leading to combined immunodeficiency is associated with microcephaly, cerebellar hypoplasia, and growth retardation. Objectives: Limited information is available on the cellular and molecular phenotypes of cells from patients with HH. We analyzed fibroblasts and whole blood cells from 5 patients with HH, 3 of them of unknown molecular origin. Methods: Telomere length, cellular senescence rate, telomerase activity, telomeric aberration, and DNA repair pathways were investigated. Results: Although patients' cells exhibit dysfunctional telomeres, sharp differences in the telomeric aberrations and telomere lengths were noted among these patients. In some patients the dysfunctional telomere phenotype was unprecedented and associated with either normal telomere length or with telomeric aberrations akin to fragile telomeres. This result is of particular importance because the molecular diagnosis of these patients is primarily based on telomere length, which therefore misses a subset of patients with telomere dysfunction. Conclusion: These observations provide the notions that (1) various telomere defects can lead to similar clinical features, (2) telomere dysfunction in cells from patients with DC/HH is not always associated with short telomeres, and (3) additional factors, likely involved in telomere protection rather than in length regulation, are responsible for a subset of DC/HH. © 2012 American Academy of Allergy, Asthma & Immunology. Source

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