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Dive into the research topics where Sandrine Eimer is active.

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Featured researches published by Sandrine Eimer.


JAMA Neurology | 2012

Long-term Outcomes of CLIPPERS (Chronic Lymphocytic Inflammation With Pontine Perivascular Enhancement Responsive to Steroids) in a Consecutive Series of 12 Patients

Guillaume Taieb; Claire Duflos; Dimitri Renard; Bertrand Audoin; Elsa Kaphan; Jean Pelletier; Nadège Limousin; Christine Tranchant; Stéphane Kremer; Jérôme De Seze; Romain Lefaucheur; David Maltête; David Brassat; Michel Clanet; Patrice Desbordes; Eric Thouvenot; Laurent Magy; Thierry Vincent; Jean-Luc Faillie; Nicolas Menjot de Champfleur; Giovanni Castelnovo; Sandrine Eimer; Dominique Figarella Branger; Emmanuelle Uro-Coste; Pierre Labauge

BACKGROUND Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) is a central nervous system inflammatory disease. OBJECTIVE To describe the disease course of CLIPPERS. DESIGN A nationwide study was implemented to collect clinical, magnetic resonance imaging, cerebrospinal fluid, and brain biopsy specimen characteristics of patients with CLIPPERS. SETTING Academic research. PATIENTS Twelve patients with CLIPPERS. MAIN OUTCOME MEASURES The therapeutic management of CLIPPERS was evaluated. RESULTS Among 12 patients, 42 relapses were analyzed. Relapses lasted a mean duration of 2.5 months, manifested frequent cerebellar ataxia and diplopia, and were associated with a mean Expanded Disability Status Scale (EDSS) score of 4. Besides typical findings of CLIPPERS, magnetic resonance imaging showed brainstem mass effect in 5 patients, extensive myelitis in 3 patients, and closed ring enhancement in 1 patient. Inconstant oligoclonal bands were found on cerebrospinal fluid investigation in 4 patients, with an increased T-cell ratio of CD4 to CD8. Among 7 available brain biopsy specimens, staining was positive for perivascular CD4 T lymphocytes in 5 samples. Thirty-eight of 42 relapses were treated with pulse corticosteroid therapy, which led to improvement, with a mean residual EDSS score of 1.9 (range, 0-7). In 1 patient with untreated relapses, scores on the EDSS progressively increased to a score of 10 at death. Among 5 patients without long-term corticosteroid therapy, the mean annualized relapse rate was 0.5 (range, 0.25-2.8). Among 7 patients taking oral corticosteroids, no relapses occurred in those whose daily dose was 20 mg or higher. No progressive course of CLIPPERS was observed. Four patients with a final EDSS score of 4 or higher had experienced previous severe relapses (EDSS score, ≥5) and brainstem and spinal cord atrophy. CONCLUSIONS CLIPPERS is a relapsing-remitting disorder without progressive forms. Long-term disability is correlated with the severity of previous relapses. Further studies are needed to confirm that prolonged corticosteroid therapy prevents further relapses.


Neuro-oncology | 2014

Contrast enhancement in 1p/19q-codeleted anaplastic oligodendrogliomas is associated with 9p loss, genomic instability, and angiogenic gene expression

German Reyes-Botero; Caroline Dehais; Ahmed Idbaih; Nadine Martin-Duverneuil; Marion Lahutte; Catherine Carpentier; Eric Letouzé; Olivier Chinot; Hugues Loiseau; Jérôme Honnorat; Carole Ramirez; Elisabeth Moyal; Dominique Figarella-Branger; François Ducray; Christine Desenclos; Henri Sevestre; Philippe Menei; Sophie Michalak; Edmond Nader; Joel Godard; Gabriel Viennet; Antoine F. Carpentier; Sandrine Eimer; Phong Dam-Hieu; Isabelle Quintin-Roué; Jean-Sébastien Guillamo; Emmanuelle Lechapt-Zalcman; Jean-Louis Kemeny; Pierre Verrelle; Thierry Faillot

BACKGROUND The aim of this study was to correlate MRI features and molecular characteristics in anaplastic oligodendrogliomas (AOs). METHODS The MRI characteristics of 50 AO patients enrolled in the French national network for high-grade oligodendroglial tumors were analyzed. The genomic profiles and IDH mutational statuses were assessed using high-resolution single-nucleotide polymorphism arrays and direct sequencing, respectively. The gene expression profiles of 25 1p/19q-codeleted AOs were studied on Affymetrix expression arrays. RESULTS Most of the cases were frontal lobe contrast-enhanced tumors (52%), but the radiological presentations of these cases were heterogeneous, ranging from low-grade glioma-like aspects (26%) to glioblastoma-like aspects (22%). The 1p/19q codeletion (n = 39) was associated with locations in the frontal lobe (P = .001), with heterogeneous intratumoral signal intensities (P = .003) and with no or nonmeasurable contrast enhancements (P = .01). The IDH wild-type AOs (n = 7) more frequently displayed ringlike contrast enhancements (P = .03) and were more frequently located outside of the frontal lobe (P = .01). However, no specific imaging pattern could be identified for the 1p/19q-codeleted AO or the IDH-mutated AO. Within the 1p/19q-codeleted AO, the contrast enhancement was associated with larger tumor volumes (P = .001), chromosome 9p loss and CDKN2A loss (P = .006), genomic instability (P = .03), and angiogenesis-related gene expression (P < .001), particularly for vascular endothelial growth factor A and angiopoietin 2. CONCLUSION In AOs, the 1p/19q codeletion and the IDH mutation are associated with preferential (but not with specific) imaging characteristics. Within 1p/19q-codeleted AO, imaging heterogeneity is related to additional molecular alterations, especially chromosome 9p loss, which is associated with contrast enhancement and larger tumor volume.


Neuro-oncology | 2012

Cyclopamine cooperates with EGFR inhibition to deplete stem-like cancer cells in glioblastoma-derived spheroid cultures

Sandrine Eimer; Frédéric Dugay; Kelly Airiau; Tony Avril; Véronique Quillien; Marc-Antoine Belaud-Rotureau; Francis Belloc

Putative cancer stem cells have been identified in glioblastoma (GBM), associated with resistance to conventional therapies. Overcoming this resistance is a major challenge to manage this deadly brain tumor. Epidermal growth factor receptor (EGFR) is commonly amplified, over-expressed, and/or mutated in GBM, making it a compelling target for therapy. This study investigates the behavior of 3 primary neurosphere (NS) cell lines and their adherent counterparts originated from human GBM resections, when treated with EGFR-tyrosine kinase inhibitor erlotinib, associated or not with cyclopamine, a hedgehog pathway inhibitor. Adherent cells cultured in the presence of serum expressed the glial fibrillary acidic protein, whereas NS-forming cells cultured in serum-free medium expressed CD133, nestin, and Oct-4, markers of neural stem and progenitor cells. For the 3 adherent cell lines, erlotinib has a moderate effect (50% inhibitory concentration [IC50], >10 µM). Conversely, erlotinib induced a strong cell growth inhibition (IC50, <1 µM) on NS-forming cells, related to the EGFR gene amplification and EGFR protein expression. A short exposure to erlotinib reduced nestin-positive cell proliferation, but NS-initiating activity and self-renewal were not altered. EGFR pathway seems essential for GBM progenitor cell proliferation but dispensable for cancer stem-like cell self-renewal. Inhibition of hedgehog pathway with cyclopamine was evaluated in association with erlotinib on NS growth. Although each drug separately had no effect on sphere initiation, their combination significantly decreased the sphere number (P < .001). Our findings show synergic efficiency for erlotinib-cyclopamine association and provide a suitable in vitro model to explore drug combinations on GBM cells.


PLOS ONE | 2012

SNP Array Analysis Reveals Novel Genomic Abnormalities Including Copy Neutral Loss of Heterozygosity in Anaplastic Oligodendrogliomas

Ahmed Idbaih; François Ducray; Caroline Dehais; Célia Courdy; Catherine Carpentier; Simon de Bernard; Emmanuelle Uro-Coste; Karima Mokhtari; Anne Jouvet; Jérôme Honnorat; Olivier Chinot; Carole Ramirez; Patrick Beauchesne; Alexandra Benouaich-Amiel; Joel Godard; Sandrine Eimer; Fabrice Parker; Emmanuelle Lechapt-Zalcman; Philippe Colin; Delphine Loussouarn; Thierry Faillot; Phong Dam-Hieu; Selma Elouadhani-Hamdi; Luc Bauchet; Olivier Langlois; Caroline Le Guerinel; Denys Fontaine; Elodie Vauleon; Philippe Menei; Marie Janette Motsuo Fotso

Anaplastic oligodendrogliomas (AOD) are rare glial tumors in adults with relative homogeneous clinical, radiological and histological features at the time of diagnosis but dramatically various clinical courses. Studies have identified several molecular abnormalities with clinical or biological relevance to AOD (e.g. t(1;19)(q10;p10), IDH1, IDH2, CIC and FUBP1 mutations). To better characterize the clinical and biological behavior of this tumor type, the creation of a national multicentric network, named “Prise en charge des OLigodendrogliomes Anaplasiques (POLA),” has been supported by the Institut National du Cancer (InCA). Newly diagnosed and centrally validated AOD patients and their related biological material (tumor and blood samples) were prospectively included in the POLA clinical database and tissue bank, respectively. At the molecular level, we have conducted a high-resolution single nucleotide polymorphism array analysis, which included 83 patients. Despite a careful central pathological review, AOD have been found to exhibit heterogeneous genomic features. A total of 82% of the tumors exhibited a 1p/19q-co-deletion, while 18% harbor a distinct chromosome pattern. Novel focal abnormalities, including homozygously deleted, amplified and disrupted regions, have been identified. Recurring copy neutral losses of heterozygosity (CNLOH) inducing the modulation of gene expression have also been discovered. CNLOH in the CDKN2A locus was associated with protein silencing in 1/3 of the cases. In addition, FUBP1 homozygous deletion was detected in one case suggesting a putative tumor suppressor role of FUBP1 in AOD. Our study showed that the genomic and pathological analyses of AOD are synergistic in detecting relevant clinical and biological subgroups of AOD.


Nature Communications | 2016

Integrated multi-omics analysis of oligodendroglial tumours identifies three subgroups of 1p/19q co-deleted gliomas

Aurélie Kamoun; Ahmed Idbaih; Caroline Dehais; Nabila Elarouci; Catherine Carpentier; Eric Letouzé; Carole Colin; Karima Mokhtari; Anne Jouvet; Emmanuelle Uro-Coste; Nadine Martin-Duverneuil; Marc Sanson; Jean-Yves Delattre; Dominique Figarella-Branger; Aurélien de Reyniès; François Ducray; Clovis Adam; Marie Andraud; Marie-Hélène Aubriot-Lorton; Luc Bauchet; Patrick Beauchesne; Franck Bielle; Claire Blechet; Mario Campone; Antoine F. Carpentier; Ioana Carpiuc; Dominique Cazals-Hatem; Marie-Pierre Chenard; Danchristian Chiforeanu; Olivier Chinot

Oligodendroglial tumours (OT) are a heterogeneous group of gliomas. Three molecular subgroups are currently distinguished on the basis of the IDH mutation and 1p/19q co-deletion. Here we present an integrated analysis of the transcriptome, genome and methylome of 156 OT. Not only does our multi-omics classification match the current classification but also reveals three subgroups within 1p/19q co-deleted tumours, associated with specific expression patterns of nervous system cell types: oligodendrocyte, oligodendrocyte precursor cell (OPC) and neuronal lineage. We confirm the validity of these three subgroups using public datasets. Importantly, the OPC-like group is associated with more aggressive clinical and molecular patterns, including MYC activation. We show that the MYC activation occurs through various alterations, including MYC genomic gain, MAX genomic loss, MYC hypomethylation and microRNA-34b/c down-regulation. In the lower grade glioma TCGA dataset, the OPC-like group is associated with a poorer outcome independently of histological grade. Our study reveals previously unrecognized heterogeneity among 1p/19q co-deleted tumours.


PLOS ONE | 2015

Accumulation of an endogenous tryptophan-derived metabolite in colorectal and breast cancers.

Paolo Puccetti; Francesca Fallarino; Antoine Italiano; Isabelle Soubeyran; Gaëtan MacGrogan; Marc Debled; Valérie Velasco; D. Bodet; Sandrine Eimer; Marc Veldhoen; Georges C. Prendergast; Michael Platten; Alban Bessede; Gilles J. Guillemin

Tumor immune escape mechanisms are being regarded as suitable targets for tumor therapy. Among these, tryptophan catabolism plays a central role in creating an immunosuppressive environment, leading to tolerance to potentially immunogenic tumor antigens. Tryptophan catabolism is initiated by either indoleamine 2,3-dioxygenase (IDO-1/-2) or tryptophan 2,3-dioxygenase 2 (TDO2), resulting in biostatic tryptophan starvation and l-kynurenine production, which participates in shaping the dynamic relationship of the host’s immune system with tumor cells. Current immunotherapy strategies include blockade of IDO-1/-2 or TDO2, to restore efficient antitumor responses. Patients who might benefit from this approach are currently identified based on expression analyses of IDO-1/-2 or TDO2 in tumor tissue and/or enzymatic activity assessed by kynurenine/tryptophan ratios in the serum. We developed a monoclonal antibody targeting l-kynurenine as an in situ biomarker of IDO-1/-2 or TDO2 activity. Using Tissue Micro Array technology and immunostaining, colorectal and breast cancer patients were phenotyped based on l-kynurenine production. In colorectal cancer l-kynurenine was not unequivocally associated with IDO-1 expression, suggesting that the mere expression of tryptophan catabolic enzymes is not sufficiently informative for optimal immunotherapy.


American Journal of Otolaryngology | 2012

Unique case of malignant transformation of a vestibular schwannoma after fractionated radiotherapy.

Konstantinos Markou; Sandrine Eimer; Clotilde Perret; Aymeri Huchet; John K. Goudakos; Dominique Liguoro; Valérie Franco-Vidal; Jean-Philippe Maire; Vincent Darrouzet

OBJECTIVE Malignant transformation of vestibular schwannoma is considered a rare clinical entity. Radiotherapy, as a treatment option for vestibular schwannoma, is regarded as a potential risk factor for secondary malignancy. Recently, radiotherapy with dose fractionation has been proposed, intended to diminish the risk of radiation-induced neuropathy. CASE PRESENTATION The aim of the present study is to report the first case, to the best of our knowledge, of malignant transformation of a residual vestibular schwannoma 19 years after fractionated radiotherapy, describing its characteristics with regard to those previously reported in the literature. CONCLUSIONS The main purpose of the present work is to state that the knowledge of the iatrogenic potential pitfalls of any technique of radiotherapy in clinical oncology is becoming a necessity. Finally, our report demonstrates that the irradiated patients must be monitored for life because a secondary malignancy may appear after a very long delay.


Clinical Neurology and Neurosurgery | 2007

Intraorbital apocrine hidrocystoma.

Jean-Rodolphe Vignes; Valérie Franco-Vidal; Sandrine Eimer; Dominique Liguoro

A 33-year-old man reported an 18 months history of a progressive right eyelid swelling, a sensation of eye pain and headaches. He noted a visual discomfort. Physical examination showed right eyelid edema, without skin lesion. The patients acuity was unchanged from the baseline; neither exophthalmia nor deficit in the visual field was noted. Magnetic resonance image showed an intraorbital, extraconal cystic lesion. Histopathologic examination revealed apocrine hidrocystoma.


Case reports in otolaryngology | 2013

Inflammatory Myofibroblastic Tumour of the Skull Base

Jean-Philippe Maire; Sandrine Eimer; François San Galli; Valérie Franco-Vidal; Sigolène Galland-Girodet; Aymeri Huchet; Vincent Darrouzet

Inflammatory myofibroblastic tumors (IMTs) are rare benign clinical and pathological entities. IMTs have been described in the lungs, abdomen, retroperitoneum, and extremities but rarely in the head and neck region. A 38-year-old man presented with headache, right exophthalmia, and right 6th nerve palsy. A CT scan revealed enlargement of the right cavernous sinus and osteolytic lesions of the right sphenoid and clivus. MR imaging showed a large tumor of the skull base which was invading the sella turcica, right cavernous sinus, and sphenoidal sinus. A biopsy was performed and revealed an IMT. Corticosteroids were given for 3 months but were inefficient. In the framework of our pluridisciplinary consultation, fractionated conformal radiotherapy (FRT) was indicated at a low dose; 20 Gy in 10 fractions of 2 Gy over 12 days were delivered. Clinical response was complete 3 months after FRT. Radiological response was subtotal 6 months after FRT. Two years later, the patient is well.


Acta Neuropathologica | 2015

TERT promoter mutations in primary central nervous system lymphoma are associated with spatial distribution in the splenium

Aurélie Bruno; Agusti Alentorn; Mailys Daniau; Marianne Labussière; Amithys Rahimian; Emeline Tabouret; Marc Polivka; Anne Jouvet; Clovis Adam; Dominique Figarella-Branger; Fabrice Chrétien; Sandrine Eimer; Caroline Houillier; Carole Soussain; Karima Mokhtari; Khê Hoang-Xuan

prognostic impact of these mutations has been described in several tumor types; moreover, the TERT polymorphism rs2853669 may influence the effect of TERT mutations on outcome [3]. To investigate the potential role of TERT promoter mutations (TERTp-mut) and/or rs2853669 genotype in the pathogenesis of PCNSL, we sequenced 49 paired bloodtumor DNA from newly diagnosed PCNSL immunocompetent patients using Sanger sequencing (for details see Supplementary material 1). We identified 8 cases (16 %) harboring somatic TERTp-mut, including 5 cases (10 %) with C250T and 4 cases (8 %) with C228T. One case harbored co-occurrence of the C228T and C250T mutations (Supplementary material 2, 3). Twenty-eight cases (57 %) Primary central nervous system lymphoma (PCNSL) is a rare and aggressive extranodal non-Hodgkin lymphoma. Its management remains a matter of debate and little is known about its tumorigenesis [4]. Novel somatic mutations in the promoter of TERT (telomerase reverse transcriptase) gene have been recently identified in a wide range of cancers including brain malignancies. The two hotspot mutations, −124C>T (C228T) and −146C>T (C250T), generate binding sites for ETS/TCF transcription factors leading to an increased transcriptional activity. Interestingly, an adverse

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Dominique Figarella-Branger

French Institute of Health and Medical Research

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Carole Colin

Aix-Marseille University

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