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Dive into the research topics where Christelle Volteau is active.

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Featured researches published by Christelle Volteau.


International Journal of Cancer | 2012

HLA‐E/β2 microglobulin overexpression in colorectal cancer is associated with recruitment of inhibitory immune cells and tumor progression

Céline Bossard; Stéphane Bézieau; Tamara Matysiak-Budnik; Christelle Volteau; Christian Laboisse; Francine Jotereau; Jean-François Mosnier

The host immune response plays a major role in colorectal carcinoma (CRC) progression. A mechanism of tumor immune escape might involve expression of the human leucocyte antigen (HLA)‐E/β2m on tumor cells. The inhibitory effect of HLA‐E/β2m on CD8+ cytotoxic T lymphocytes and natural killer (NK) cells is mediated by the main HLA‐E receptor CD94/NKG2A. As the pathophysiological relevance of this mechanism in CRC remains unknown, this prompted us to examine, in situ, in a series of 80 CRC (i) the HLA‐E and β2m coexpression by tumor cells, (ii) the density of CD8+, cytotoxic, CD244+ and NKP46+ intraepithelial tumor‐infiltrating lymphocyte (IEL‐TIL) and (iii) the expression of CD94/NKG2 receptor on IEL‐TIL. These data were then correlated to patient survival. We provided (i) the in situ demonstration of HLA‐E/β2m overexpression by tumor cells in 21% of CRC characterized by an overrepresentation of signet ring cell carcinomas, mucinous carcinomas and medullary carcinomas, (ii) the significant association between HLA‐E/β2m overexpression by tumor cells and increased density of CD8+ cytotoxic, CD244+ and CD94+ IEL‐TIL and (iii) finally, the unfavorable prognosis associated with HLA‐E/β2m overexpression by tumor cells. Our findings show that HLA‐E/β2m overexpression is a surrogate marker of poor prognosis and point to a novel mechanism of tumor immune escape in CRC in restraining inhibitory IEL‐TIL.


Annals of Family Medicine | 2014

Targeted Melanoma Prevention Intervention: A Cluster Randomized Controlled Trial

Cédric Rat; G. Quereux; Christelle Riviere; Sophie Clouet; Rémy Senand; Christelle Volteau; Brigitte Dreno; Jean-Michel Nguyen

PURPOSE Targeted interventions to reduce the risk and increase the early detection of melanoma have the potential to save lives. We aimed to assess the effect of such an intervention on patient prevention behavior. METHODS We conducted a pilot clustered randomized controlled trial, comparing a targeted screening and education intervention with a conventional information-based campaign in 20 private surgeries in western France. In the intervention group, 10 general practitioners identified patients at elevated risk for melanoma with a validated assessment tool, the Self-Assessment Melanoma Risk Score (SAMScore), examined their skin, and counseled them using information leaflets. In the control group, 10 general practitioners displayed a poster and the leaflets in their waiting room and examined patients’ skin at their own discretion. The main outcome measures were sunbathing and skin self-examinations among patients at elevated risk, assessed 5 months later with a questionnaire. RESULTS Analyses were based on 173 patients. Compared with control patients, intervention patients were more likely to remember the campaign (81.4% vs 50.0%, P = .0001) and to correctly identify their elevated risk of melanoma (71.1% vs 42.1%, P = .001). Furthermore, intervention patients had higher levels of prevention behaviors: they were less likely to sunbathe in the summer (24.7% vs 40.8%, P = .048) and more likely to have performed skin self-examinations in the past year (52.6% vs 36.8%, P = .029). The intervention was not associated with any clear adverse effects, although there were trends whereby intervention patients were more likely to worry about melanoma and to consult their general practitioner again about the disease. CONCLUSIONS The combination of use of the SAMScore and general practitioner examination and counseling during consultations is an efficient way to promote patient behaviors that may reduce melanoma risk. Extending the duration of follow-up and demonstrating an impact on morbidity and mortality remain major issues for further research.


Experimental Dermatology | 2009

Cytomegalovirus: its potential role in the development of cutaneous T-cell lymphoma.

F. Ballanger; C. Bressollette; Christelle Volteau; L. Planche; B. Dréno

Abstract:  To investigate the potential role of CMV in cutaneous T‐cell lymphoma (CTCL), we studied cytomegalovirus (CMV) seroprevalence in parapsoriasis (PP), mycosis fungoides (MF) and Sézary syndrome (SS) compared with healthy control patients. In cases where CMV seropositivity was observed, CMV PCR analyses were performed on skin biopsies. CMV seroprevalence was 37.1% in the control group, 50.68% in the PP + MF + SS group (P = 0.08), 56.2% in the MF + SS group (P = 0.07), 40% in the PP group (P = 0.9), 66.67% in the MF group (P = 0.009), 42.86% in the SS group (P = 0.9). CMV PCR in initial skin biopsies were all negative. However, PCR CMV was positive in two SS skin biopsies realized at an advanced stage. Our results show that latent CMV infection may play a role in the susceptibility of MF in predisposed subjects by inducing T‐cell proliferation and resistance to apoptosis. Concerning SS, an immunosuppressive state may be responsible for CMV reactivation that in turn may interfere with evolution of the disease.


European Journal of Cancer Prevention | 2010

Creation and test of a questionnaire for self-assessment of melanoma risk factors.

G. Quereux; Jean-Michel Nguyen; Christelle Volteau; Yves Lequeux; Brigitte Dreno

The objective of this study was to create a self-administrated questionnaire for people to enable them to assess their own melanoma risk factors. To test the validity of this questionnaire in a large prospective study, the answers given by the patient were systematically checked by his or her general practitioner. In this prospective study, the choice of questions was based on a review of the literature. The validity of the questionnaire was assessed by testing 1500 consecutive patients attending a consultation with their general practitioner. Considerable variations concerning the prevalence of different melanoma risk factors were noticed in the population: 44.1% had a phototype I or II, 41% had severe sunburn during infancy, 29.9% had freckling tendency, 22% had more than 50 naevi and 1.4% a personal history of melanoma. In total, 45% had more than one melanoma risk factor. The accuracy of the answers given by the patients was assured by the correction given by their general practitioners. The percentage of correct answers given by the patients was 79.9% for the phototype, 90.6% for freckling tendency, 86.6% for the number of naevi, 96.5% for severe sunburn during infancy and 98.1 and 95.8% for personal and familial history of melanoma. This study confirms that individuals with multiple risk factors for melanoma are common among patients consulting their general practitioners. Furthermore, self-screening with the self-assessment questionnaire is easily feasible and is accurate for identifying high-risk individuals. This tool might be useful for carrying out melanoma-targeted screening.


European Journal of Cancer Prevention | 2009

Prospective trial on a school-based skin cancer prevention project.

G. Quereux; Jean-Michel Nguyen; Christelle Volteau; Brigitte Dreno

The objective of this study was to assess the impact of an educational programme on both childrens knowledge and behaviour towards the sun. The study included 282 children aged between 8 and 11 years in their third year of primary school coming from 13 schools in the Nantes area (located in the west of France). It was a two-arm opened control trial, with group A in which the children were taught by their teacher about their skin and sun protection, according to the programme called ‘to live with the sun’ and a control group (B) in which the children did not receive any educational programme about sun protection. Self-administrated questionnaires at the baseline, posttest and follow-up were used to assess knowledge and behaviour of the students. The data were paired to follow the evolution of each child and a knowledge score and a sun protection habits score were calculated. At the baseline there was no significant difference in knowledge and sun protection habits scores between the two groups. Six months after the educational prevention programme we observed a knowledge score significantly higher in group A (mean: 7.66) compared with group B (mean: 6.77) (P<0.00001), but concerning the sun protection habits score there was no significant difference between the two groups. The programme had a beneficial effect on the childrens knowledge persisting for at least a few months but had no impact on their behaviour towards the sun.


Clinical Neurology and Neurosurgery | 2016

Randomized placebo-controlled trial of sodium valproate in progressive supranuclear palsy

Laurène Leclair-Visonneau; Tiphaine Rouaud; Bérangère Debilly; Franck Durif; Jean-Luc Houeto; Alexandre Kreisler; Luc Defebvre; E. Lamy; Christelle Volteau; Jean-Michel Nguyen; Séverine Le Dily; Philippe Damier; Claire Boutoleau-Bretonnière; Pascal Lejeune; Pascal Derkinderen

OBJECTIVES Results from preclinical studies suggest that inhibition of glycogen synthase kinase (GSK-3) is a therapeutic option for tauopathies. The aim of the present study was therefore to determine the effects of sodium valproate (VPA), a GSK-3 inhibitor, on disease progression in progressive supranuclear palsy (PSP). PATIENTS AND METHODS We performed a double-blind, randomized, placebo-controlled trial, in 28 PSP patients who received VPA (1500mg/day) or matching placebo for 24 months. The primary endpoint was the change from baseline in Progressive Supranuclear Palsy Rating Scale (PSPRS) at 12 and 24 months. Secondary endpoints evaluated the effects of VPA on cognitive and behavioral status (MMSE, Mattis Dementia Rating Scale, Wisconsin Card Sorting, Gröber and Buschke and Oral Denomination 80 tests), tolerability of treatment, and patient compliance. RESULTS There were no baseline differences between active treatment and placebo groups in age and clinical rating scores. PSPRS score at 12 months was significantly higher in the VPA than in the placebo group (60.8±20 versus 46.9±18.6 respectively, p=0.01), but was similar between the two groups at 24 months. No significant differences were observed between VPA and placebo groups for the secondary endpoints. CONCLUSION Our results suggest that VPA is not effective as a disease-modifying agent in PSP.


Acta Odontologica Scandinavica | 2013

A recall program for the outcome of conventional root canal treatment performed in a teaching hospital

Bénédicte Castelot-Enkel; Jean-Michel Nguyen; Valérie Armengol; Christelle Volteau; Olivier Laboux; Pierre Lombrail; Pierre Weiss

Abstract Objectives: This study investigated the long-term survival and the prognostic factors of endodontic treatments performed in a dental teaching hospital. The aim was to calculate the probabilities of success or failure according to the follow-up extent and to assess the time allowed for a complete periapical healing. Materials and methods. A cohort of 185 teeth were re-examined 1–4 years after treatment. The outcome was assessed on the basis of radiographic and clinical criteria as success, uncertain or failure. A survival analysis using the Cox model was used (i) to explore tooth survival and periapical healing over the time and (ii) to highlight the predictive factors of treatment outcome. Results. After 2 years, the appearance of an apical periodontitis remained lower than 3.5%, whereas only 22.8% of periapical healed cases were notified. The prognosis factors are: (i) for teeth with initial healthy periapical conditions, coronal leakage (p = 0.002) with the higher risk of failure (RR = 19.77), absence of correspondence filling length/shaping = 0.026), type of teeth (p = 0.041) and (ii) for teeth with apical periodontitis, number of root canals (p = 0.000,91), correspondence filling length/shaping length (p = 0.017) and over-filling (p = 0.09). New periapical lesions or tooth loss were recorded after 2 years. Half of the successful cases of periapical healing were observed during the follow-up from 2–4 years. Conclusions. This longitudinal study shows that coronal leakage is responsible for late failure and that periapical healing is long to achieve. Therefore, endodontic treatments may require a follow-up of over 2 years.


Experimental Dermatology | 2008

Absence of amplification of CD4+CD25high regulatory T cells during in vitro expansion of tumor‐infiltrating lymphocytes in melanoma patients

Anne Chantal Knol; Fabrice Lemaître; Marie Christine Pandolfino; Christelle Volteau; G. Quereux; Soraya Saiagh; Amir Khammari; Manuelle Viguier; Brigette Dréno

Abstract:  The exact role of CD4+CD25high regulatory T cells (Treg) in adoptive immunotherapy of melanoma is still to be determined, and an association between an expansion of Treg cells and the expansion of therapeutic tumor‐infiltrating lymphocytes (TIL) remains unelucidated. In this context, the aim of our study was to determine whether functional Treg cells were detectable and amplified among in vitro‐expanded TIL from 10 metastatic melanoma lymph nodes (LNs). In this study, we investigated the expression of forkhead/winged helix transcription factor 3 (Foxp3) in melanoma‐invaded LNs and determined proportion and functionality of Treg cells among TIL extracted from these 10 metastatic melanoma LNs at different steps of their in vitro expansion. We found that metastatic melanoma LNs expressed very heterogeneous levels of Foxp3 and that CD4+CD25high Treg cells extracted from these LNs were detectable at each step of the in vitro culture of TIL but decreasing during the culture. In addition, functional assays demonstrated that these CD4+CD25high T cells were capable of suppressing autologous CD8+ and CD4+CD25‐ T cell proliferation. These cells were indeed Treg cells as they expressed Foxp3. In conclusion, our work suggests that CD4+CD25high Foxp3 expressing T cells are not expanded during in vitro amplification of TIL obtained from melanoma‐invaded LNs.


Endoscopy International Open | 2016

Antireflux versus conventional self-expanding metallic Stents (SEMS) for distal esophageal cancer: results of a multicenter randomized trial.

Emmanuel Coron; G. David; S Lecleire; J. Jacques; A Le Sidaner; Thierry Barrioz; Dimitri Coumaros; Christelle Volteau; Bertrand Vedrenne; Philippe Bichard; C. Boustière; Yann Touchefeu; J. Brégeon; Frédéric Prat; M. Le Rhun

Introduction: Self-expanding metal stents (SEMS) are commonly used in the palliation of dysphagia in patients with inoperable esophageal carcinoma. However, they predispose to gastroesophageal reflux when deployed across the gastroesophageal junction. The aims of this study were to: 1) assess the influence of the antireflux valve on trans-prosthetic reflux (primary outcome); and 2) compare the results of SEMS with and without antireflux valve in terms of reflux symptoms, quality of life (QOL), improvement of dysphagia and adverse events (secondary outcomes). Patients and methods: Thirty-eight patients were enrolled in nine centers. Carcinomas were locally advanced (47 %) or metastatic. After randomization, patients received either a covered SEMS with antireflux valve (n = 20) or a similar type of SEMS with no antireflux device but assigned to standard proton pump inhibitor therapy and postural advice (n = 18). Trans-prosthetic reflux was assessed at day 2 using a radiological score based on barium esophagography performed after Trendelenburg maneuver and graded from 0 (no reflux) to 12 (maximum). Monthly telephone interviews were conducted for Organisation Mondiale de la Santé (OMS) scoring from 0 (excellent) to 5 (poor), QOL assessment (based on the Reflux-Qual Simplifié scoring system) from 0 (poor) to 100 (excellent), dysphagia scoring from 0 (no dysphagia) to 5 (complete dysphagia) and regurgitation scoring from 0 (no regurgitation) to 16 (maximum). Results: No difference was noted in terms of age, sex, size of lesion, prosthesis length or need for dilation prior to SEMS placement. No difficulty in placing SEMS nor complications were noted. Radiological scores of reflux were found to be significantly lower in patients with an antireflux stent compared to the conventional stent and associated measures. The regurgitation scores were significantly decreased in patients with antireflux stents during the first 2 months after stent placement and thereafter, they were similar in the two groups. QOL and dysphagia were improved in both groups. Survival rates were comparable in the two groups. Conclusions: No difference was observed between the two types of SEMS regarding the palliation of dysphagia and improvement of QOL. However, SEMS with an antireflux valve were more effective in preventing trans-prosthetic gastroesophageal reflux but at the cost of an increased likehood of minor adverse events (migrations and/or obstruction of the SEMS).


Laboratory Investigation | 2015

Heterogeneity of subordination of the IL-18/IFN-γ axis to caspase-1 among patients with Crohn's disease.

Anne Jarry; Céline Bossard; Laure Droy-Dupré; Christelle Volteau; Arnaud Bourreille; Guillaume Meurette; Jean-François Mosnier; Christian L. Laboisse

In Crohn’s disease (CD), hierarchical architecture of the inflammatory network, including subordination of IL-18, an IFN-γ-inducing cytokine, to the inflammasome, have remained undeciphered. Heterogeneity among patients of such a subordination cannot be evaluated by animal models, monofactorial in their etiology and homogenous in disease progression. To address these issues, we set up an ex vivo model of inflamed mucosa explant cultures from patients with active long-standing CD. Th1 cytokine production, especially IFN-γ and IL-18, was assessed in relation with inflammation intensity. Subordination of the Th1 response to caspase-1, effector of the inflammasome, was determined in explant cultures subjected to pharmacological inhibition of caspase-1 by YVAD. We showed a correlation between secreted IFN-γ/IL-18 levels, and caspase-1 activation, with inflammation intensity of intestinal CD mucosa explants. Inhibition of caspase-1 activation using the specific inhibitor YVAD identified a homogenous non responder group featuring a caspase-1-independent IL-18/IFN-γ response, and a heterogenous responder group, in which both IL-18 and IFN-γ responses were caspase-1-dependent, with a 40–70% range of inhibition by YVAD. These findings bring out the concept of heterogeneity of subordination of the Th1 response to inflammasome activation among CD patients. This ex vivo model should have therapeutic relevance in allowing to determine eligibility of CD patients for new targeted therapies.

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E Coron

University of Nantes

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Christian L. Laboisse

Case Western Reserve University

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