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Dive into the research topics where Barbara Petit is active.

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Featured researches published by Barbara Petit.


Blood | 2011

Efficacy of L-asparaginase with methotrexate and dexamethasone (AspaMetDex regimen) in patients with refractory or relapsing extranodal NK/T-cell lymphoma, a phase II study.

Arnaud Jaccard; Nathalie Gachard; Benoît Marin; Sylvie Rogez; Marie Audrain; Felipe Suarez; Hervé Tilly; Franck Morschhauser; Catherine Thieblemont; Loic Ysebaert; Alain Devidas; Barbara Petit; Laurence de Leval; Philippe Gaulard; Jean Feuillard; Dominique Bordessoule; Olivier Hermine

Extranodal NK/T-cell lymphoma, nasal type, is a rare and highly aggressive disease with a grim prognosis. No therapeutic strategy is currently identified in relapsing patients. We report the results of a French prospective phase II trial of an L-asparaginase-containing regimen in 19 patients with relapsed or refractory disease treated in 13 centers. Eleven patients were in relapse and 8 patients were refractory to their first line of treatment. L-Asparaginase-based treatment yielded objective responses in 14 of the 18 evaluable patients after 3 cycles. Eleven patients entered complete remission (61%), and only 4 of them relapsed. The median overall survival time was 1 year, with a median response duration of 12 months. The main adverse events were hepatitis, cytopenia, and allergy. The absence of antiasparaginase antibodies and the disappearance of Epstein-Barr virus serum DNA were significantly associated with a better outcome. These data confirm the excellent activity of L-asparaginase-containing regimens in extranodal NK/T-cell lymphoma. L-Asparaginase-based treatment should thus be considered for salvage therapy, especially in patients with disseminated disease. First-line L-asparaginase combination therapy for extranodal NK/T-cell lymphoma warrants evaluation in prospective trials. This trial is registered at www.clinicaltrials.gov as #NCT00283985.


Blood | 2010

Gene expression profiling identifies emerging oncogenic pathways operating in extranodal NK/T-cell lymphoma, nasal type

Yenlin Huang; Aurélien de Reyniès; Laurence de Leval; Bouchra Ghazi; Nadine Martin-Garcia; Marion Travert; Jacques Bosq; Josette Briere; Barbara Petit; Emilie Thomas; Paul Coppo; Teresa Marafioti; Jean-François Emile; Marie-Hélène Delfau-Larue; Christian Schmitt; Philippe Gaulard

Biopsies and cell lines of natural killer/T-cell lymphoma, nasal type (NKTCL) were subject to combined gene expression profiling and array-based comparative genomic hybridization analyses. Compared with peripheral T-cell lymphoma, not otherwise specified, NKTCL had greater transcript levels for NK-cell and cytotoxic molecules, especially granzyme H. Compared with normal NKcells, tumors were closer to activated than resting cells and overexpressed several genes related to vascular biology, Epstein-Barr Virus-induced genes, and PDGFRA. Notably, platelet-derived growth factor receptor alpha and its phosphorylated form were confirmed at the protein level, and in vitro the MEC04 NKTCL cell line was sensitive to imatinib. Deregulation of the AKT, Janus kinase-signal transducers and activators of transcription, and nuclear factor-kappaB pathways was corroborated by nuclear expression of phosphorylated AKT, signal transducers and activators of transcription 3, and RelA in NKTCL, and several deregulated genes in these pathways mapped to regions of recurrent copy number aberrations (AKT3 [1q44], IL6R [1q21.3], CCL2 [17q12], TNFRSF21 [6p12.3]). Several features of NKTCL uncovered by this analysis suggest perturbation of angiogenic pathways. Integrative analysis also evidenced deregulation of the tumor suppressor HACE1 in the frequently deleted 6q21 region. This study highlights emerging oncogenic pathways in NKTCL and identifies novel diagnostic and therapeutic targets.


Annals of Oncology | 2008

L-Asparaginase-based treatment of 15 western patients with extranodal NK/T-cell lymphoma and leukemia and a review of the literature

Arnaud Jaccard; Barbara Petit; S. Girault; Felipe Suarez; R. Gressin; Jean-Marc Zini; Valérie Coiteux; C. Larroche; Alain Devidas; Catherine Thieblemont; Philippe Gaulard; Benoît Marin; Nathalie Gachard; Dominique Bordessoule; Olivier Hermine

BACKGROUND Extranodal natural killer (NK)/T-cell lymphoma, nasal type, and aggressive NK-cell leukemia are highly aggressive diseases with a poor outcome. PATIENTS AND METHODS We report a multicentric French retrospective study of 15 patients with relapsed, refractory, or disseminated disease, treated with L-asparaginase-containing regimens in seven French centers. Thirteen patients were in relapse and/or refractory and 10 patients were at stage IV. RESULTS All but two of the patients had an objective response to L-asparaginase-based treatment. Seven patients reached complete remission and only two relapsed. CONCLUSION These data, although retrospective, confirm the excellent activity of L-asparaginase-containing regimens in refractory extranodal NK/T-cell lymphoma and aggressive NK-cell leukemia. Therefore, L-asparaginase-based regimen should be considered as a salvage treatment, especially for patients with disseminated disease. First-line L-asparaginase combination therapy for extranodal NK/T-cell lymphoma and aggressive NK-cell leukemia should be tested in prospective trials.


Leukemia | 2013

IGHV gene features and MYD88 L265P mutation separate the three marginal zone lymphoma entities and Waldenström macroglobulinemia/lymphoplasmacytic lymphomas

Nathalie Gachard; M. Parrens; Isabelle Soubeyran; Barbara Petit; Abdelghafour Marfak; David Rizzo; M. Devesa; Manuela Delage-Corre; V. Coste; Marie-Pierre Laforêt; A. De Mascarel; Jean Philippe Merlio; K. Bouabdhalla; Noel-Jean Milpied; Pierre Soubeyran; A. Schmitt; Dominique Bordessoule; Michel Cogné; Jean Feuillard

To clarify the relationships between marginal zone lymphomas (MZLs) and Waldenström macroglobulinemia/lymphoplasmacytic lymphomas (WM/LPLs), immunoglobulin heavy chain variable gene (IGHV) features were analyzed and the occurrence of MYD88 L265P mutations was identified in a series of 123 patients: 53 MZLs from the spleen (SMZLs), 11 from lymph nodes (NMZLs), 28 mucosa-associated lymphatic tissue (MALT) lymphomas and 31 WM/LPLs. SMZLs were characterized by overrepresentation of IGHV1–2 gene rearrangements with a canonical motif, without selection pressure and with long CDR3 segments. NMZLs had increased frequencies of IGHV3 genes. The IGHV gene was unmutated in most cases, often with long CDR3 segments. MALT lymphomas were usually associated with a mutated IGHV gene, but with the absence of selection pressure. WM/LPLs were associated with an IGHV3–23 overrepresentation and high IGHV mutation rate, with features of selection pressure and short CDR3 segments. MYD88 L265P mutations were almost restricted exclusively to WM/LPL patients. Taken all diagnoses together, all patients with MYD88 L265P mutations had an immunoglobulin M peak and almost all patients except one had bone marrow infiltration. These results demonstrate that the history of antigen exposure of the four entities studied was different and MYD88 L265P was specifically associated with WM/LPLs. WM/LPL may thus be functionally associated with constitutive nuclear factor-κB activation.


The American Journal of Surgical Pathology | 2009

Peripheral T-cell lymphomas with a follicular growth pattern are derived from follicular helper T cells (TFH) and may show overlapping features with angioimmunoblastic T-cell lymphomas.

Yenlin Huang; Anne Moreau; Jehan Dupuis; Berthold Streubel; Barbara Petit; Steven Le Gouill; Nadine Martin-Garcia; Christiane Copie-Bergman; Fanny Gaillard; Marwan Qubaja; Bettina Fabiani; Giovanna Roncador; Corinne Haioun; Marie-Hélène Delfau-Larue; Teresa Marafioti; Andreas Chott; Philippe Gaulard

Rare cases of peripheral T-cell lymphomas with follicular growth pattern (PTCL-F) have been recently reported, and their association with t(5;9)(q33;q22) involving ITK and SYK has been suggested. However, the clinicopathologic aspects of PTCL-F are poorly described and the normal cell counterpart of this subgroup of lymphoma is still unknown. Therefore, we analyzed the pathologic, phenotypic, and cytogenetic features of a series of 30 patients (range: 33 to 88 y) that showed histopathologic features of PTCL-F in at least 1 biopsy (n=30), either at initial presentation (n=26) or at relapse (n=4). Neoplastic cells were medium-sized clear cells that were CD4+ (24/27, 89%), CD10+ (21/29, 72%), BCL-6+ (14/19, 74%), and expressed programed death-1 (27/27, 100%), CXCL13 (23/27, 85%), and ICOS (11/11, 100%), markers of follicular helper T cells (TFH). Four of 22 patients (18%) had t(5;9)(q33;q22) detected by fluorescence in situ hybridization. Patients with clinical data available had multiple lymphadenopathies (25/28, 89%), stage III to IV diseases (17/26, 65%), B symptoms (7/27, 26%), and skin lesions (6/23, 26%). Three patients with sequential biopsies disclosed clinical and histopathologic features of angioimmunoblastic T-cell lymphoma at initial presentation. Our results show that this rare form of PTCL-F (1) has an immunophenotype indicative of derivation from TFH cells, (2) is associated with t(5;9) in a proportion of cases, and (3) shows some overlapping features with angioimmunoblastic T-cell lymphoma, raising the question of a possible relationship.


Journal of Clinical Microbiology | 2002

Real-time PCR for quantification of human herpesvirus 6 DNA from lymph nodes and saliva.

Sophie Collot; Barbara Petit; Dominique Bordessoule; Sophie Alain; Mohamed Touati; François Denis; Sylvie Ranger-Rogez

ABSTRACT A real-time quantitative PCR assay has been developed to measure human herpesvirus 6 (HHV-6) DNA in biological specimens. The assay sensitivity was 10 copies of DNA per well, with a linear dynamic range of 10 to 107 copies of HHV-6 DNA. Intra- and interassay variations were, respectively, 0.88 and 0.8% for samples containing 102 DNA copies, 0.99 and 0.96% for samples containing 104 copies, and 0.76 and 0.9% for samples containing 106 copies. Among 34 saliva samples from healthy subjects, 26 were found to contain HHV-6 DNA (76.5%; median, 23,870 copies/ml), and following a single freeze-thaw cycle, 25 of the same samples were found to be positive for HHV-6 DNA, although at a statistically significantly lower concentration (median, 3,497 copies/ml). The assay enabled detection of HHV-6 DNA in lymph node biopsies from patients with Hodgkins disease (HD) (13 of 37 patients [35.1%]), B-cell neoplasms (8 of 36 patients [22.2%]), and T- or NK-cell neoplasms (3 of 13 patients [23.1%]), with concentrations ranging from 100 to 864,640 HHV-6 copies per μg of DNA (HHV-6B being found in every case except two). All HD patients infected with HHV-6 presented clinically with the nodular sclerosis subtype of HD. The real-time quantitative PCR assay developed here was simple to perform and was sensitive over a wide range of HHV-6 concentrations. It therefore appears to be of potential value in clinical investigation or diagnosis of HHV-6 infection.


Journal of Immunology | 2007

The 3′ IgH Locus Control Region Is Sufficient to Deregulate a c-myc Transgene and Promote Mature B Cell Malignancies with a Predominant Burkitt-Like Phenotype

Véronique Truffinet; Eric Pinaud; Nadine Cogné; Barbara Petit; Laurence Guglielmi; Michel Cogné; Yves Denizot

Burkitt lymphoma (BL) features translocations linking c-myc to an Ig locus. Breakpoints in the H chain locus (IgH) stand either close to JH or within switch regions and always link c-myc to the 3′ IgH locus control region (3′ LCR). To test the hypothesis that the 3′ LCR alone was sufficient to deregulate c-myc, we generated mice carrying a 3′ LCR-driven c-myc transgene and specifically up-regulating c-myc in B cells. Splenic B cells from mice proliferated exaggeratedly in response to various signals had an elevated apoptosis rate but normal B220/IgM/IgD expression. Although all Ig levels were lowered in vivo, class switching and Ig secretion proved normal in vitro. Beginning at the age of 12 wk, transgenic mice developed clonal lymphoblastic lymphomas or diffuse anaplastic plasmacytomas with an overall incidence of 80% by 40 wk. Lymphoblastic lymphomas were B220+IgM+IgD+ with the BL “starry sky” appearance. Gene expression profiles revealed broad alterations in the proliferation program and the Ras-p21 pathway. Our study demonstrates that 3′ IgH enhancers alone can deregulate c-myc and initiate the development of BL-like lymphomas. The rapid and constant occurrence of lymphoma in this model makes it valuable for the understanding and the potential therapeutic manipulation of c-myc oncogenicity in vivo.


Transplantation | 2002

Influence of host-recipient origin on clinical aspects of posttransplantation lymphoproliferative disorders in kidney transplantation

Barbara Petit; Yann Le Meur; Arnaud Jaccard; François Paraf; Claude Leroux Robert; Dominique Bordessoule; François Labrousse; Mireille Drouet

BACKGROUND Posttransplantation lymphoproliferative disorder (PTLD) is a well-known complication of immunosuppression associated with solid organ transplantation. The donor or host origin of PTLD may influence the outcome of the disease as it has been reported that a donor origin may be associated with a better prognosis. The aim of the study was to determine the origin (recipient or donor) of 12 PTLD occurring in kidney transplant recipients and to correlate the results with clinical findings. METHODS Origin of PTLD was determined using HLA DRB1 molecular typing, analysis of multiple short-tandem repeat microsatellite loci, and HLA class I antigen expression by immunohistochemistry. RESULTS Combining the three techniques, we found that eight cases originated from the recipient and four cases originated from the donor. The results of the three techniques were concordant and altogether assigned the origin of the tumors. All the donor-origin PTLD were strictly localized to the kidney graft, developed after a mean time of 5 months after transplantation, and regressed after reduction of immunosuppression. In contrast, seven of the eight recipient-origin PTLD presented as multisystemic disease, occurred a mean time of 75.7 months after the transplantation, and had a worse outcome (mortality, five deaths of eight patients, 62.5%). CONCLUSIONS These results suggest that PTLD originating from the donor arise in the first year after transplantation into the graft, and that recipient-origin PTLD develop later as an invasive disease. Because it permits simultaneously the analysis of cell morphology and tumor origin, immunohistochemistry is a more reliable technique in the case of graft tumors associated with allograft rejection. The determination of the origin of the tumors seems to be of value in the management of PTLD to predict the outcome and to adapt therapy.


Clinical Cancer Research | 2008

T Cell Receptor Genotyping and HOXA/TLX1 Expression Define Three T Lymphoblastic Lymphoma Subsets which Might Affect Clinical Outcome

Frederic Baleydier; Anne-Valerie Decouvelaere; Julie Bergeron; Philippe Gaulard; Danielle Canioni; Yves Bertrand; Stéphane Leprêtre; Barbara Petit; Hervé Dombret; Kheira Beldjord; Thierry Molina; Vahid Asnafi; Elizabeth Macintyre

Purpose: T lymphoblastic lymphomas (T-LBL) are rare disorders of immature T cells which predominantly involve the mediastinum. Their oncogenic pathways and prognostic variables are not clear. Experimental Design: We undertook a retrospective study of 41 cytoplasmic CD3+ T-LBL (nine cases aged <16 years) by assessing stage of maturation arrest based on T cell receptor (TCR) immunogenotyping, immunohistochemistry, and quantification of the oncogenes thought to be important in immature T cell malignancies. Results: Application of a TCR-based immunogenetic classification allowed the identification of three subcategories: 11 immature IM0/D-LBL showed no TCR or only incomplete TCRD DJ rearrangement and corresponded to cytoplasmic CD3+ precursors of uncertain lineage. Sixteen mature TCRDdel-LBL showed biallelic TCRD deletion and both TCRG and TCRB rearrangement, consistent with TCRαβ lineage restriction. Fourteen intermediate LBL (Int-LBL) showed complete TCRD VDJ and TCRG VJ rearrangement, with TCRB VDJ rearrangement in the majority. All Int-LBL expressed HOX11/TLX1 or HOXA9 transcripts and a proportion of the latter were associated with CALM-AF10 or NUP214-ABL fusion transcripts. IM0/D-LBL were restricted to adults with extrathymic disease and bone marrow involvement, whereas Int-LBL and TCRDdel-LBL were found in children and adults with predominantly thymic disease. In adults, the Int-LBL subgroup was associated with a significantly superior clinical outcome. This subgroup can be identified either by TCR immunogenotyping or HOXA9/TLX1 transcript quantification. Conclusion: Application of this molecular classification will allow the prospective evaluation of prognostic effects within pediatric and adult protocols.


Clinical Cancer Research | 2010

Involvement of Human Herpesvirus-6 Variant B in Classic Hodgkin's Lymphoma via DR7 Oncoprotein

Aurélie Lacroix; Sophie Collot-Teixeira; Laurent Mardivirin; Arnaud Jaccard; Barbara Petit; Christophe Piguet; Franck Sturtz; Pierre-Marie Preux; Dominique Bordessoule; Sylvie Ranger-Rogez

Purpose: Hodgkins lymphoma (HL) is associated with the presence of EBV in Reed-Sternberg (RS) cells in ∼40% of cases. Here, we studied the presence of human herpesvirus type 6 (HHV-6) variant B in RS cells of HL patients and correlated results with clinical parameters. We then examined the implication of HHV-6 DR7B protein in cell deregulation. Experimental Design: HHV-6 DR7B protein was produced in a Semliki Forest virus system. Polyclonal antibodies were then generated and used for immunochemical HHV-6 localization in HL biopsies. Binding between DR7B and p53 was studied using a double-hybrid system. Transactivation of NFκB was observed after transient transfection using reporter gene assays. We looked for Id2 factor expression after stable transfection of the BJAB cell line by reverse transcription-PCR and Western blot analysis. Results: HHV-6 was more common in nodular sclerosis subtype HL, and DR7B oncoprotein was detected in RS cells for 73.7% of EBV-negative patients. Colocalization of EBV and HHV-6 was observed in RS cells of doubly infected patients. DR7B protein bound to human p53 protein. p105-p50/p65 mRNA expression and activation of the NFκB complex were increased when DR7B was expressed. Stable expression of DR7B exhibited a strong and uniform expression of Id2. A slightly higher percentage of remission was observed in patients with RS cells testing positive for DR7B than in those testing negative. Conclusions: Collectively, these data provide evidence for the implication of a novel agent, HHV-6, in cases of nodular sclerosis HL. Clin Cancer Res; 16(19); 4711–21. ©2010 AACR.

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Dive into the Barbara Petit's collaboration.

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Dominique Bordessoule

Centre national de la recherche scientifique

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François Labrousse

Centre national de la recherche scientifique

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Jean Feuillard

Centre national de la recherche scientifique

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Nathalie Gachard

Centre national de la recherche scientifique

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Michel Cogné

Centre national de la recherche scientifique

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Abdelghafour Marfak

Centre national de la recherche scientifique

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Felipe Suarez

Paris Descartes University

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