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International audience; Follicular lymphoma (FL) is a common non Hodgkin's lymphoma subtype in which immune escape mechanisms are implicated in resistance to chemo-immunotherapy. Although molecular studies point to qualitative and quantitative deregulation of immune checkpoints, in depth cellular analysis of FL immune escape is lacking. Here, by functional assays and in silico analyses we show that a subset of FL patients displays a 'high' immune escape phenotype. These FL cases are characterized by abundant infiltration of PD1+ CD16+ TCRVγ9Vδ2 γδ T lymphocytes. In a 3D co-culture assay (MALC), γδ T cells mediate both direct and indirect (ADCC in the presence of anti-CD20 mAbs) cytolytic activity against FL cell aggregates. Importantly, PD-1, which is expressed by most FL-infiltrating γδ T lymphocytes with ADCC capacity, impairs these functions. In conclusion, we identify a PD1-regulated γδ T cell cytolytic immune component in FL. Our data provide a treatment rational by PD-1 blockade aimed at boosting γδ T cell anti-tumor functions in FL.

AIMS: Vinflunine is a novel tubulin‐targeted inhibitor indicated as a single agent for the treatment of bladder cancers after failure of prior platinum‐based therapy. Its pharmacokinetics (PK) and pharmacodynamics (PD) have been independently characterized through several phase I and phase II studies. However, no global pharmacometric analysis had been conducted as yet. METHODS: Vinflunine concentrations and safety data from 18 phase I and phase II studies were used to conduct population PK and PK/PD analysis, using Nonmem. A four‐compartment model was used to describe vinflunine PK and several covariates were tested to explain interindividual variability. In terms of PK/PD relationship, a semiphysiological population PK/PD model was applied to describe time course of absolute neutrophil counts (ANC) after vinflunine administration and logistic regression models were used to test the relationship between vinflunine exposure and toxicities. RESULTS: Vinflunine clearance is explained by creatinine clearance, body surface area and combination with PEGylated doxorubicin, leading to a decrease from 28.2 to 25.3% of the interindividual variability. When vinflunine dose is decreased, simulations of ANC time course (via a semiphysiological model) after vinflunine administration show a risk of neutropenia grade 3–4 at cycle 2 always lower than when dose is delayed. As an example, for moderate renal impaired patients, the risk is 42.1% when vinflunine is dosed at 320 mg m(–2) once every 4 weeks vs. 23.3% for 280 mg m(–2) once every 3 weeks. CONCLUSIONS: We propose for the first time a global comprehensive clinical pharmacological analysis for intravenous vinflunine that may help drive dose adjustment.

International audience; Ca(2+) is an essential factor inducing keratinocyte differentiation due to the natural Ca(2+) gradient in the skin. However, the membrane mechanisms that mediate calcium entry and trigger keratinocyte differentiation had not previously been elucidated. In this study we demonstrate that Ca(2+)-induced differentiation up-regulates both mRNA and protein expression of a transient receptor potential highly Ca(2+)-selective channel, TRPV6. The latter mediates Ca(2+) uptake and accounts for the basal [Ca(2+)](i) in human keratinocytes. Our results show that TRPV6 is a prerequisite for keratinocyte entry into differentiation, because the silencing of TRPV6 in human primary keratinocytes led to the development of impaired differentiated phenotype triggered by Ca(2+). The expression of such differentiation markers as involucrin, transglutaminase-1, and cytokeratin-10 was significantly inhibited by small interfering RNA-TRPV6 as compared with differentiated control cells. TRPV6 silencing affected cell morphology and the development of intercellular contacts, as well as the ability of cells to stratify. 1,25-Dihydroxyvitamin D3, a cofactor of differentiation, dose-dependently increased TRPV6 mRNA and protein expression in human keratinocytes. This TRPV6 up-regulation led to a significant increase in Ca(2+) uptake in both undifferentiated and differentiated keratinocytes. We conclude that TRPV6 mediates, at least in part, the pro-differentiating effects of 1,25-dihydroxyvitamin D3 by increasing Ca(2+) entry, thereby promoting differentiation. Taken together, these data suggest that the TRPV6 channel is a key element in Ca(2+)/1,25-dihydroxyvitamin D3-induced differentiation of human keratinocytes.

International audience; Introduction et but de l'étude: La supplémentation orale en arginine a un effet bénéfique sur des fonctions associées au monoxyde d'azote (NO) chez des sujets avec des facteurs de risque cardiovasculaires. Cet effet semble dépendre de la dose et de l'augmentation de l'arginine plasmatique qui en résulte, mais aussi de la situation physiopathologique. Aucune donnée ne permet cependant de lier la mise à disposition de l'arginine et la synthèse de NO, en situation normale ou de risque cardiométabolique. L'objectif de cette étude était de comparer la biodisponibilité de l'arginine ingérée et son utilisation pour la synthèse de NO (1) selon qu'elle est consommée sous une forme à libération immédiate (LI) ou sous une forme à libération prolongée (LP) mimant la mise à disposition naturellement lente de l'arginine alimentaire, et (2) selon la présence de facteurs de risque du syndrome métabolique. Matériel et méthodes: Dans une étude avec répartition au hasard, selon un protocole croisé, nous avons comparé la biodisponibilité et l'utilisation pour la synthèse de NO d'arginine LP et LI (1,5g, 3 fois par jour) consommée pendant une semaine chez 15 sujets sains témoins et 12 sujets sains présentant un « tour de taille hypertriglycéridémique » (TTH). Nous avons pour cela utilisé de l'arginine marquée ([ 15 N 2-(guanido)]-arginine) et des dosages isotopiques plasmatiques et urinaires pour suivre l'apparition de l'arginine ingérée dans la circulation systémique et sa conversion spécifique en NO. Résultats et Analyse statistique: Au niveau cinétique, comme attendu, les augmentations des concentrations plasmatiques en arginine ingérée, en arginine totale et en ornithine totale étaient moins brutales et plus étalées après arginine-LP que LI. Au bilan, concernant les aires sous courbe (AUCs) plasmatiques sur 24h, l'AUC de l'arginine ingérée était moins importante après la supplémentation en arginine-LP que LI, tandis que les AUCs de l'arginine et ornithine totales étaient peu variables selon la forme (LP ou LI) et la durée (premier ou dernier jour) de la supplémentation. Par ailleurs, l'utilisation de l'arginine ingérée pour la synthèse de NO était plus élevée chez les sujets TTH que chez les témoins, et elle était plus élevée avec la forme LP qu'avec la forme LI, en particulier chez les sujets TTH (Ps

International audience; La supplémentation en L-arginine atténue la dysfonction endothéliale postprandiale lorsque l'argininémie basale est faible chez des sujets sains présentant des facteurs de risque du syndrome métabolique Veuillez choisir votre discipline: Clinique Présentation préférée: Communication orale Spécifiez votre âge

International audience; Four alkaloids named hosieines A–D were isolated from the root and stem of Ormosia hosiei. Their flat structures were established by mass spectrometry and by a combination of NMR experiments. These molecules probably share a common biosynthetic origin with the lupin alkaloids but they differ in the formation of the last ring, being here part of a rare 2-azabicyclo[3.2.1]octane system. Their absolute configuration was determined by X-ray crystallography using CuKα radiation. As has been described for cytisine, they display a remarkable affinity towards neuronal nicotinic acetylcholine α4β2 receptor.

Atrial fibrillation (AF) is a common complication of heart failure. The aim of the present study was to investigate the effects of a new pure docosahexaenoic acid derivative called F 16915 in experimental models of heart failure-induced atria dysfunction. The atrial dysfunction-induced AF was investigated (1) in a dog model of tachypacing-induced congestive heart failure and (2) in a rat model of heart failure induced by occlusion of left descending coronary artery and 2 months reperfusion. F 16915 (5 g/day for 4 weeks) significantly reduced the mean duration of AF induced by burst pacing in the dog model (989 +/- 111 s in the vehicle group to 79 +/- 59 s with F 16915, P < 0.01). This dose of F 16915 also significantly reduced the incidence of sustained AF (5/5 dogs in the vehicle group versus 1/5 with F 16915, P < 0.05). In the rat model, the percentage of shortening fraction in the F 16915 group (100 mg/kg p.o. daily) was significantly restored after 2 months (32.6 +/- 7.4 %, n = 9 vs 17.6 +/- 3.4 %, n = 9 in the vehicle group, P < 0.01). F 16915 also reduced the de-phosphorylation of connexin43 from atria tissue. The present results show that treatment with F 16915 reduced the heart dilation, resynchronized the gap junction activity, and reduced the AF duration in models of heart failure. Thus, F 16915 constitutes a promising new drug as upstream therapy for the treatment of AF in patients with heart failure.

International audience; The physiological status of native skin is suffering from large inter-individual variations, especially in terms of inorganic ions content. For this reason, together with the advent of ethic laws on animal experimentation, reconstructed skin or epidermis models are extensively employed nowadays in penetration studies for cosmetic or pharmacological applications. It has been already verified that reconstructed human epidermis (RHE) has similar physiological mechanisms to native human skin, but until now, there are few studies where the elemental concentrations of both skins, reconstructed and native, are compared. In this work, freeze-dried thin sections of human native skin obtained from surgery have been characterized using PIXE, RBS and STIM at the CENBG nuclear microprobe. RHE samples were treated and analyzed in the same conditions for comparison. The combination of the different imaging and analysis techniques made possible a clear delimitation and identification of skin ultrastructure. The elemental concentrations of P, S, Cl, K and Ca were measured in the different strata. For both skins, concentrations have been compared and significant differences in terms of elemental concentrations have been determined using statistical approaches. Similar physiological characteristics were pointed out in both skin models, in particular the Ca gradient presumably involved in the regulation of the barrier effect.

Bio-guided fractionation of an extract from Tanacetum parthenium showing activity as mitotic blocker allowed the isolation and identification of santin 3, jaceidin 2 and centaureidin 1. The latter two closely related flavonols, which, to the best of our knowledge, are isolated here together for the first time, form a mixture difficult to resolve and which is probably the reason for the confusion in the literature regarding their occurrence. Centaureidin 1 had an IC50 of 1 microM while jaceidin 2 and santin 3 were 200 times less active.

Introduction: In the JAVELIN Lung 200 trial, avelumab (anti-programmed death-ligand 1 [PD-L1] antibody) did not significantly prolong overall survival (OS) versus docetaxel in patients with platinum-treated PD-L1+ NSCLC. We report greater than 2-year follow-up data. Methods: Patients with stage IIIB or IV or recurrent NSCLC with disease progression after platinum-doublet chemotherapy were randomized 1:1 to avelumab 10 mg/kg every 2 weeks or docetaxel 75 mg/m(2) every 3 weeks. The primary end point was OS in patients with PD-L1+ tumors (greater than or equal to 1% tumor cell expression; IHC 73-10 pharmDx assay). Results: Of 792 patients, 529 had PD-L1+ tumors (264 versus 265 in the avelumab versus docetaxel arms, respectively). As of March 4, 2019, median duration of follow-up for OS in the PD L1+ population was 35.4 months in the avelumab arm and 34.7 months in the docetaxel arm; study treatment was ongoing in 25 (9.5%) versus 0 patients, respectively. In the PD-L1+ population, 2-year OS rates (95% confidence interval [CI]) with avelumab versus docetaxel were 29.9% (24.5%-35.5%) versus 20.5% (15.6%-25.8%); in greater than or equal to 50% PD L1+ subgroups, 2-year OS rates were 36.4% (29.1%-43.7%) versus 17.7% (11.8%-24.7%) and in the greater than or equal to 80% subgroup were 40.2% (31.3%-49.0%) versus 20.3% (12.9%-28.8%), respectively. Median duration of response (investigator assessed) was 19.1 months (95% CI: 10.8-34.8) versus 5.7 months (95% CI: 4.1-8.3). Safety profiles for both arms were consistent with the primary analysis. Conclusions: Although the JAVELIN Lung 200 primary analysis (reported previously) revealed that avelumab did not significantly prolong OS versus docetaxel in patients with platinum-treated PD-L1+ NSCLC, posthoc analyses at 2 years of follow-up revealed that 2-year OS rates were doubled with avelumab in subgroups with higher PD-L1 expression (greater than or equal to 50% and greater than or equal to 80%). (C) 2021 International Association for the Study of Lung Cancer. Published by Elsevier Inc., EMD Serono Research & Development Institute, Inc., an affiliate of Merck KGaA, Darmstadt, Germany; Pfizer; Merck KGaA, LL This study was sponsored by EMD Serono Research & Development Institute, Inc., an affiliate of Merck KGaA, Darmstadt, Germany, as part of an alliance between Merck KGaA and Pfizer. Employees of the sponsor are coauthors of this manuscript and contributed to the design, execution, and interpretation of the analyses being reported, writing the report, and the decision to submit the article for publication, along with the other coauthors. The authors thank the patients and their families; the investigators, coinvestigators, and study teams at each participating center and at Merck KGaA, Darmstadt, Germany, and EMD Serono Research & Development Institute, Inc., Billerica, MA, an affiliate of Merck KGaA, Darmstadt, Germany, and Quintiles (Durham, NC) . Medical writing support was provided by Abhijith Thippeswamy of ClinicalThinking and funded by Merck KGaA and Pfizer.

The formation of DNA photoproducts caused by solar UVR exposure needs to be investigated in-vivo and in particular in order to assess sunscreens' level of protection against solar genotoxicity. The study's purposes were: i) to evaluate if the roof of suction blisters is an appropriate sampling method for measuring photoproducts, and ii) to measure in-vivo sunscreen protection against cyclobutane pyrimidine dimers. Skin areas on the interior forearms of eight healthy volunteers were exposed in-vivo to 2 MED of simulated solar radiation (SSR) and to 15 MED on a sunscreen protected area. After irradiation, six suction blisters were induced and the blister roofs were collected. Analysis of SSR-induced CPDs was performed by two independent methods: a chromatography coupled to mass spectroscopy (HPLC-MS/MS) approach and a 3D-imaging of CPD immunostaining by multiphoton microscopy on floating epidermal sheets. HPLC-MS/MS analyses showed that SSR-unexposed skin presented no CPD dimers, whereas 2 MED SSR-exposed skin showed a significant number of TT-CPD. The sunscreen covered skin exposed to 15 MED appeared highly protected from DNA damage, as the amount of CPD-dimers remained below the detection limit. The multiphoton-immunostaining analysis consistently showed that no CPD staining was observed on the non-SSR-exposed skin. A significant increase of CPD staining intensity and number of CPD-positive cells were observed on the 2 MED SSR-exposed skin. Sunscreen protected skin presented a very low staining intensity and the number of CPD-positive cells remained very close to non-SSR-exposed skin. This study showed that suction blister samples are very appropriate for measuring CPD dimers in-vivo, and that sunscreens provide high protection against UVR-induced DNA damage.

Background In breast cancer, the epithelial to mesenchyme transition (EMT) is associated to tumour dissemination, drug resistance and high relapse risks. It is partly controlled by epigenetic modifications such as histone acetylation and methylation. The identification of genes involved in these reversible modifications represents an interesting therapeutic strategy to fight metastatic disease by inducing mesenchymal cell differentiation to an epithelial phenotype. Methods We designed a siRNA library based on chromatin modification-related to functional domains and screened it in the mesenchymal breast cancer cell line MDA-MB-231. The mesenchyme to epithelium transition (MET) activation was studied by following human E-CADHERIN (E-CAD) induction, a specific MET marker, and cell morphology. Candidate genes were validated by studying the expression of several differential marker genes and their impact on cell migration. Results The screen led to the identification of 70 gene candidates among which some are described to be, directly or indirectly, involved in EMT like ZEB1, G9a, SMAD5 and SMARCD3. We also identified the DOT1L as involved in EMT regulation in MDA-MB-231. Moreover, for the first time, KAT5 gene was linked to the maintenance of the mesenchymal phenotype. Conclusions A multi-parametric RNAi screening approach was developed to identify new EMT regulators such as KAT5 in the triple negative breast cancer cell line MDA-MB-231. Electronic supplementary material The online version of this article (doi:10.1186/s12885-016-2683-5) contains supplementary material, which is available to authorized users.

International audience; PURPOSE: The Gastro-Intestinal Working Party of the EORTC Radiation Oncology Group (GIWP-ROG) developed guidelines for target volume definition in neoadjuvant radiation of adenocarcinomas of the gastroesophageal junction (GEJ) and the stomach. METHODS AND MATERIALS: Guidelines about the definition of the clinical target volume (CTV) are based on a systematic literature review of the location and frequency of local recurrences and lymph node involvement in adenocarcinomas of the GEJ and the stomach. Therefore, MEDLINE was searched up to August 2008. Guidelines concerning prescription, planning and treatment delivery are based on a consensus between the members of the GIWP-ROG. RESULTS: In order to support a curative resection of GEJ and gastric cancer, an individualized preoperative treatment volume based on tumour location has to include the primary tumour and the draining regional lymph nodes area. Therefore we recommend to use the 2nd English Edition of the Japanese Classification of Gastric Carcinoma of the Japanese Gastric Cancer Association which developed the concept of assigning tumours of the GEJ and the stomach to anatomically defined sub-sites corresponding respectively to a distinct lymphatic spread pattern. CONCLUSION: The GIWP-ROG defined guidelines for preoperative irradiation of adenocarcinomas of the GEJ and the stomach to reduce variability in the framework of future clinical trials.

International audience; BACKGROUND: Use of cetuximab, a monoclonal antibody targeting the epidermal growth factor receptor (EGFR), has the potential to increase survival in patients with advanced non-small-cell lung cancer. We therefore compared chemotherapy plus cetuximab with chemotherapy alone in patients with advanced EGFR-positive non-small-cell lung cancer. METHODS: In a multinational, multicentre, open-label, phase III trial, chemotherapy-naive patients (>or=18 years) with advanced EGFR-expressing histologically or cytologically proven stage wet IIIB or stage IV non-small-cell lung cancer were randomly assigned in a 1:1 ratio to chemotherapy plus cetuximab or just chemotherapy. Chemotherapy was cisplatin 80 mg/m(2) intravenous infusion on day 1, and vinorelbine 25 mg/m(2) intravenous infusion on days 1 and 8 of every 3-week cycle) for up to six cycles. Cetuximab-at a starting dose of 400 mg/m(2) intravenous infusion over 2 h on day 1, and from day 8 onwards at 250 mg/m(2) over 1 h per week-was continued after the end of chemotherapy until disease progression or unacceptable toxicity had occurred. The primary endpoint was overall survival. Analysis was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00148798. FINDINGS: Between October, 2004, and January, 2006, 1125 patients were randomly assigned to chemotherapy plus cetuximab (n=557) or chemotherapy alone (n=568). Patients given chemotherapy plus cetuximab survived longer than those in the chemotherapy-alone group (median 11.3 months vs 10.1 months; hazard ratio for death 0.871 [95% CI 0.762-0.996]; p=0.044). The main cetuximab-related adverse event was acne-like rash (57 [10%] of 548, grade 3). INTERPRETATION: Addition of cetuximab to platinum-based chemotherapy represents a new treatment option for patients with advanced non-small-cell lung cancer. FUNDING: Merck KGaA.

International audience; Induction of skin cancer is the most deleterious effect of excessive exposure to sunlight. Accurate evaluation of sunscreens to protect the genome is thus of major importance. In particular, the ability. of suncare products to prevent the formation of DNA damage should be evaluated more directly since the Sun Protection Factor is only related to erythema induction. For this purpose, we developed an in vitro approach using a recently characterized reconstituted human epidermis (RHE) model engineered from hair follicle. The relevance of this skin substitute in terms of UV-induced genotoxicity was compared to ex vivo explants exposed to solar-simulated radiation (SSR). The yield of bipyrimidine photoproducts, their rate of repair, and the induction of apoptosis were very similar in both types of skin samples. In order to evaluate the protection afforded by sunscreen against DNA damage, bipyrimidine photoproducts were quantified in tissue models following SSR exposure in the presence or absence of a SPF50+ formula. A rather high DNA protection factor of approximately 20 was found in RHE, very similar to that determined for explants. Thus, RHE is a good surrogate to human skin, and also a convenient and useful tool for investigation of the genoprotection of sunscreens. (C) 2015 Elsevier B.V. All rights reserved.

Summary Background Early diagnosis and rapid surgical excision are essential for improving the prognosis of patients with melanoma. Reflectance confocal microscopy has been validated as a feasible procedure for in vivo diagnosis of melanoma but cannot be used to measure tumour thickness. However, ultrasonography and optical coherence tomography may allow melanoma thickness to be measured in vivo. Objectives To validate the accuracy and reliability of high-frequency ultrasonography (HFUS) and optical coherence tomography for assessing melanoma thickness in vivo. Methods We conducted a prospective study on 131 patients with at least one equivocal melanocytic lesion. Each lesion underwent optical coherence tomography and HFUS assessment, followed by excision and pathological examination. Histopathology was considered to be the gold standard for assessing melanoma thickness. Repeatability, inter- and intrarater reproducibility and reliability were evaluated for each imaging procedure. Results Ultrasonography showed a good level of agreement with histology [intraclass correlation coefficient (ICC) 0·807; 95% confidence interval (CI) 0·703–0·877] and excellent inter-rater reproducibility (G = 0·97), resulting in reliable in vivo assessment of melanoma thickness. The 930-nm optical coherence tomography showed a poor level of agreement with histopathology (ICC 0·0; 95% CI −0·2–0·2) and the inter-rater reproducibility was null (G = 0·00). Conclusions HFUS is a reliable and reproducible noninvasive method for assessing melanoma thickness. Routine use of HFUS may allow single-step excision of equivocal melanocytic lesions, with surgical margins determined by in vivo assessment of tumour thickness.

International audience; BACKGROUND: A previously published study of temozolomide concurrent with whole-brain radiation therapy (WBRT) reported significant improvement in response rates and a nonsignificant trend toward improved overall survival compared with WBRT alone in patients with brain metastases primarily from lung cancer. This study sought to confirm the benefit of adding temozolomide to WBRT in patients with non-small-cell lung cancer (NSCLC) with brain metastases. PATIENTS AND METHODS: This planned phase III study (target = 380 events) was converted to a phase II study (target = 70 events) because of poor enrollment. Patients with NSCLC and > or = 1 newly diagnosed brain lesion were randomized to WBRT (30 Gy in 10 fractions) alone or combined with temozolomide (75 mg/m2/day) for 21 or 28 days. Endpoints included overall survival and time to central nervous system (CNS) progression. RESULTS: Median overall survival and median time to CNS progression was 4.4 and 3.1 months in the WBRT + temozolomide arm (n = 47) versus 5.7 and 3.8 months in the WBRT arm (n = 48). However, there were imbalances in the percentages of patients receiving previous chemotherapy and with synchronous brain metastases. Adding temozolomide to WBRT increased the frequency of nausea, vomiting, alopecia, fatigue, anorexia, and constipation. Most adverse events were mild to moderate. CONCLUSION: The benefit of adding temozolomide to WBRT was not confirmed; however, the accrual goal for the planned phase III trial was not reached, and the study regimen differed from regimens used previously. Therefore, the role of temozolomide in treating brain metastases remains unresolved.

This study was conducted to retrospectively compare the area under the curve (AUC) and the total clearance of busulfan (Bu) following oral and intravenous (IV) administrations and to determine which intravenous dose generated equivalent exposure to that of the oral form that has been marketed for decades. Patient pharmacokinetics were assessed at dose 9 during a conditioning regimen for stem-cell transplantation and included data from 277 patients for oral Bu (71 from fixed-dose studies and 206 from studies with dose adjustment allowed) and 120 patients for IV Bu (fixed dose). AUCs were compared between patients with fixed dose of oral Bu (n = 71, 1 mg/kg) and those of IV Bu (n = 120, 0.8 mg/kg). Total clearances were calculated for all 277 patients with oral Bu and compared to those with IV Bu, with the ratio of IV-to-oral clearance representing the absolute bioavailability of the oral form. Oral and IV populations differed on disease-type distribution but presented comparable demography parameters. IV Bu dosing was mostly based on the ideal body weight index while actual body weight or adjusted ideal body weight indexes were mostly used for oral. When normalised to comparable indexes, bioequivalent AUCs were achieved between oral and IV populations. Oral Bu bioavailability was about 80% when calculated from the ratio of IV-to-oral total clearances. This retrospective study carried out on a large set of data showed that similar plasma exposures were achieved with 1.0 mg/kg oral Bu or 0.8 mg/kg IV Bu.

Purpose Oral mucositis is a common side effect induced by radio/chemotherapy in patients with head and neck cancer. Although it dramatically impairs patient quality of life, no efficient and safe therapeutic solution is available today. Therefore, we investigated the protective efficacy of a new heparan mimetic biopolymer, RGTA-OTR4131, used alone or in combination with amifostine, for oral mucositis and simultaneously evaluated its effect on tumor growth in vitro and in vivo . Methods and Materials A single dose of 16.5 Gy was selectively delivered to the snout of mice, and the effects of OTR4131 or amifostine-OTR4131 were analyzed by macroscopic scoring and histology. The effect of OTR4131 administration on tumor growth was then investigated in vitro and in xenograft models using two cell lines (HEP-2 and HT-29). Results Amifostine and OTR4131 significantly decreased the severity and duration of lip mucosal reactions. However, amifostine has to be administered before irradiation, whereas the most impressive protection was obtained when OTR4131 was injected 24 h after irradiation. In addition, OTR4131 was well tolerated, and the combination of amifostine and OTR4131 further enhanced mucosal protection. At the tumor level, OTR4131 did not modify HEP-2 cell line clonogenic survival in vitro or protect xenografted tumor cells from radiotherapy. Of interest, high doses of OTR4131 significantly decreased clonogenic survival of HT-29 cells. Conclusions RGTAs-OTR4131 is a well-tolerated, natural agent that effectively reduces radio-induced mucositis without affecting tumor sensitivity to irradiation. This suggests a possible transfer into the clinic for patients' benefit.

Purpose: The precise determination of skin's mechanical properties is still an open question. When performing an in vivo test, the piece of skin tested is not as well defined as it is in material testing. Moreover, the body zone and the body posture imply an initial stress on the skin. Consequently, a precise mechanical analysis needs a precise measurement of the natural skin tension. Methods: A new method and the relative device are presented. It is based on an extensiometry test. Skin is tested not only in traction but also in compression. The tested skin sample is well defined and protected from surrounding effects by follower tabs. The size and shape of the device have been optimised by a finite element modelisation. Results: The method was tested with elastomers pre-tensioned at different loads. It is shown that the initial tension can be retrieved with good precision. Tests were then performed in vivo on the forearm for different arm positions. It is shown that initial tension could be only clearly determined for the highest skin tension, although the skin presented very different traction behaviour with different arm positions. Conclusion: It is shown how body posture influences measurements. An innovative method for easily determining initial tension is presented. Nevertheless, further tests and device improvements are needed to apply this skin tension measurement for different body zones and body postures.

International audience; The mechanical properties of the skin are of potential interest in the identification of certain diseases, for assessing therapeutic intervention, or for predicting the effect of trauma. Due to its unusual structure, the skin presents a nonlinear viscoelastic anisotropic quasi incompressible mechanical behaviour which has to be studied in vivo. In this paper, a new method to identify the viscoelastic parameters of the human skin in vivo is presented. It lies in an inverse approach which compares experimental and finite element numerical results. Current works generally propose different approaches and hypotheses which consequently give results difficult to analyze. In this paper, two types of experimental tests are performed on the same subjects so as to compare the results obtained and to underline the advantages of the proposed method.; L'analyse des composantes mécaniques de la peau est d'une importance primordiale pour divers domaines tels la dermatologie, la chirurgie et la cosmétique. En raison de sa structure particulière, le tissu cutané présente un comportement complexe viscoélastique non linéaire anisotrope et quasi-incompressible, qui doit de surcroît être étudié de manière in vivo. Nous proposons dans cet article une méthode innovante d'analyse des caractéristiques viscoélastiques de la peau. Cette dernière repose sur une approche inverse du problème, couplant résultats expérimentaux et simulations numériques par éléments finis. Deux essais mécaniques effectués sur un même individu sont considérés. Une comparaison des résultats obtenus est ainsi possible afin de mener une discussion relative, d'une part aux phénomènes induits par chacun de ces tests, et, d'autre part, à l'originalité de l'approche.

In a previous study, we have described that UVB induces granzyme B (GrB) in human keratinocyte cells, and that confers potent cellular cytotoxicity against various cellular models, including immune cells (Hernandez-Pigeon, H., Jean, C., Charruyer, A., Haure, M. J., Titeux, M., Tonasso, L., Quillet-Mary, A., Baudouin, C., Charveron, M., and Laurent, G. (2006) J. Biol. Chem. 281, 13525-13532). Herein, we have found that, in contrast to UVB, UVA failed to enhance keratinocyte cellular cytotoxicity but was still able to trigger GrB production. We show that GrB is accumulated through a p38 MAPK-dependent transcriptional mechanism stimulated by redox-dependent migration inhibitory factor release. Moreover, GrB purified from UVA-treated cellular extracts was found to degrade fibronectin in vitro. Treatment with antisense oligonucleotide directed against GrB resulted in the inhibition of UVA-induced cell detachment and cell death and facilitated cell migration through fibronectin and vitronectin matrix upon UVA exposure. Altogether, these results suggest another function for GrB in the context of the UV response. Indeed, combined with our previous study, it appears that, whereas this enzyme mediates keratinocyte cellular cytotoxicity following UVB irradiation, GrB supports the capacity of keratinocyte to degrade extracellular matrix components following UVA irradiation. UV-mediated GrB production may thus have important consequences in photoaging and photocarcinogenesis.

December 9-13; International audience

The quality control of chiral drugs requires the determination of their enantiomeric purity. Nowadays, circular dichroism (CD) spectroscopy is gaining increasing importance in pharmaceutical analysis because of the commercially available CD detector in liquid chromatography. The separation of the two enantiomers of a basic drug (efaroxan) was achieved by high performance liquid chromatography using an amylose-derivated column with both UV and CD detections. A baseline-resolved separation (resolution: 5) was obtained after optimization of the mobile phase composition with hexane-ethanol-diethylamine (90:10:0.05; v/v/v). The use of a commercial low-pass electronic noise filter of the CD signal has improved the signal-to-noise ratio by a factor twelve and allowed the quantitation of each enantiomer in the 1.25-300 microg ml(-1) concentration range. The CD linear calibration curve, expressed in terms of stereoisomer height ratio versus concentration ratio, was plotted over the 0.4-6% range. A correlation coefficient greater than 0.999 was obtained by least-squares regression and the limit of detection for the distomer/eutomer ratio was estimated at 0.14%. Although the method validation showed good repeatability on the retention times (RSD0.9%), on the peak height ratios (RSD8.7%) of each enantiomer only up to 99.2% enantiomeric purity was achieved.

As part of our search for new antimalarial drugs, we have screened for inhibitors of Pfnek-1, a protein kinase of Plasmodium falciparum, in south Pacific marine sponges. On the basis of a preliminary screening, the ethanolic crude extract of a new species of Xestospongia collected in Vanuatu was selected for its promising activity. A bioassay-guided fractionation led us to isolate xestoquinone which inhibits Pfnek-1 with an IC50 around 1 mu M. Among a small panel of plasmodial protein kinases, xestoquinone showed modest protein kinase inhibitory activity toward PfPK5 and no activity toward PfPK7 and PfGSK-3. Xestoquinone showed in vitro antiplasmodial activity against a FCB1 P. falciparum strain with an IC50 of 3 mu M and a weak selectivity index (SI 7). Xestoquinone exhibited a weak in vivo activity at 5 mg/kg in Plasmodium berghei NK65 infected mice and was toxic at higher doses. (c) 2006 Elsevier Ltd. All rights reserved.

Ultraviolet (UV) radiation from the sun is widely considered as a major cause of human skin photoaging and skin cancer. Granzyme B (GrB) and perforin (PFN) are two proteins contained in granules and implicated in one of the mechanisms by which cytotoxic lymphocytes and natural killer cells exert their cytotoxicity against virus-infected, alloreactive, or transformed cells. The distribution of GrB and PFN in the skin has received little attention. However, Berthou and co-workers (Berthou, C., Michel, L., Soulie, A., Jean-Louis, F., Flageul, B., Dubertret, L., Sigaux, F., Zhang, Y., and Sasportes, M. (1997) J. Immunol. 159, 5293-5300) described that, whereas freshly isolated epidermal cells did not express GrB or PFN, keratinocyte growth to confluence was associated with GrB and PFN mRNA and protein synthesis. In this work, we have investigated the possible role of UV-B on GrB and PFN expression in keratinocytes. We found that UV-B induces GrB and PFN expression in these cells through redox-, epidermal growth factor receptor-, and mitogen-activated protein kinase-dependent signaling. Furthermore, under UV irradiation, keratinocytes acquire a significant cytotoxicity, which is GrB and PFN dependent, toward a variety of cellular targets including transformed T-lymphocytes, melanocytes, and keratinocytes. This phenomenon may have important functional consequences in the regulation of skin inflammatory response and in the emergence of cancer skin.

18-21 avril

International audience

International audience; To determine whether compounds are able to reach the neural microenvironment, a blood-brain barrier (BBB) co-culture model has been recently developed with bovine brain capillary endothelial cells and newborn rat astrocytes. In this study, the permeability of confluent endothelial cells to various compounds and the functional activity of P-glycoprotein (P-gp), an ATP-dependent pump known to efflux drugs from multidrug-resistant tumoral cells, was assessed. The permeability of the lipophilic compounds imipramine and sulpiride differed in relation to their structure. A good correlation was observed with in vivo brain extraction levels. P-gp activity was estimated by measuring the uptake of [3H]vinblastine by the endothelial cells, with or without verapamil, which is known to reverse drug resistance. Intracellular accumulation of the vinca alkaloid was strongly increased after addition of verapamil, suggesting that P-gp is active in these cells. These results provide further support for the use of the co-culture model of bovine brain endothelial cells and rat astrocytes to screen new centrally active drugs.