Multiplex degenerate PCR coupled with an oligo sorbent array for human endogenous retrovirus expression profiling

Human endogenous retroviruses (HERVs) can be divided into distinct families of tens to thousands of paralogous loci. The expression of HERV elements has been detected in all tissues tested to date, particularly germ cells, embryonic tissues and neoplastic tissues. Hence, the study of HERV expression could represent added value in cancer diagnosis. We developed a quantitative assay combining a multiplex degenerate PCR (MD-PCR) amplification, based on the relative conservation of the pol genes, and a colorimetric Oligo Sorbent Array (OLISA(®)). Nine HERV families were selected and amplification primers and capture probes were designed for each family. The features required to achieve efficient amplification of most of the elements of each HERV family and balanced co-amplification of all HERV families were analyzed. We found that MD-PCR reliability, i.e. equivalence of amplification and dose-effect relationship, relied on the adjustment of three critical parameters: the primer degeneracy, the relative concentration of each primer and the total amount of primers in the amplification mixture. The analysis of tumoral versus normal tissues suggests that this assay could prove useful in tumor phenotyping

Natural history of the ERVWE1 endogenous retroviral locus

BACKGROUND: The human HERV-W multicopy family includes a unique proviral locus, termed ERVWE1, whose full-length envelope ORF was preserved through evolution by the action of a selective pressure. The encoded Env protein (Syncytin) is involved in hominoid placental physiology. RESULTS: In order to infer the natural history of this domestication process, a comparative genomic analysis of the human 7q21.2 syntenic regions in eutherians was performed. In primates, this region was progressively colonized by LTR-elements, leading to two different evolutionary pathways in Cercopithecidae and Hominidae, a genetic drift versus a domestication, respectively. CONCLUSION: The preservation in Hominoids of a genomic structure consisting in the juxtaposition of a retrotransposon-derived MaLR LTR and the ERVWE1 provirus suggests a functional link between both elements

A new role under sortilin's belt in cancer.

The neurotensin receptor-3 also known as sortilin was the first member of the small family of vacuolar protein sorting 10 protein domain (Vps10p) discovered two decades ago in the human brain. The expression of sortilin is not confined to the nervous system but sortilin is ubiquitously expressed in many tissues. Sortilin has multiple roles in the cell as a receptor or a co-receptor, in protein transport of many interacting partners to the plasma membrane, to the endocytic pathway and to the lysosomes for protein degradation. Sortilin could be considered as the cells own shuttle system. In many human diseases including neurological diseases and cancer, sortilin expression has been shown to be deregulated. In addition, some studies have highlighted that the extracellular domain of sortilin is shedded into the culture media by an unknown mechanism. Sortilin can be released in exosomes and appears to control some mechanisms of exosome biogenesis. In lung cancer cells, sortilin can associate with two receptor tyrosine kinase receptors called the TES complex found in exosomes. Exosomes carrying the TES complex can convey a microenvironment control through the activation of ErbB signaling pathways and the release of angiogenic factors. Deregulation of sortilin function is now emerging to be implicated in four major human diseases- cardiovascular disease, Type 2 diabetes mellitus, Alzheimer’s disease and cancer

Management of inflammatory bowel disease in France: a nationwide survey among private gastroenterologists

Introduction : Les données sur la gestion actuelle des patients atteints de maladie inflammatoire chronique intestinale (MICI) sont rares. Matériel et méthodes : Il s’agissait d’une enquête nationale sur internet réalisée auprès de gastro-entérologues libéraux sous forme de questions à choix multiples en Juin 2012. Résultats : 375 patients atteints de MICI ont été inclus : 48 % d’entre eux avaient une rectocolite hémorragique (RCH). Un antécédent d’hospitalisation concernait un tiers des patients atteints de MICI, et un antécédent de chirurgie 40 % des patients atteints de maladies de Crohn (MC). Deux tiers des patients avaient une maladie active le jour de la consultation (l’activité de la maladie était jugée par le médecin sans score). Soixante pour cent des patients atteints de RCH étaient traités par 5-aminosalicylés contre 18,5 % de MC (p<0,001). Parmi les patients traités par anti-TNF, seulement 4,5 % recevaient un traitement concomitant par immunomodulateur. La moitié des patients avaient eu une coloscopie dans l’année. Concernant le dépistage du cancer colorectal, des biopsies étagées et la chromoendoscopie étaient réalisées dans respectivement 75 % et 40 % des cas. Un score endoscopique d’activité n’était utilisé que chez 10 % des patients. Environ un tiers des patients ayant une MICI avait eu une imagerie dans l’année : l’entéro-IRM représentait environ la moitié de ces prescriptions. Le scanner a été prescrit chez 12 % des patients et l’échographie chez seulement 7 %. Conclusion : De nombreux patients ont encore une maladie active à l’ère des biothérapies, et la proportion de patients recevant une association anti-TNF et azathioprine reste faible en médecine libérale. La coloscopie est toujours la référence pour évaluer l’activité des MICI même si l’IRM est de plus en plus pratiquée. La chromoendoscopie et les scores endoscopiques sont encore sous-utilisés.Background: Data on the current management of inflammatory bowel disease (IBD) are scarce. Materials and Methods: This was a web-based nationwide survey consisting of multiple-choice questions among private gastroenterologists in France in June 2012. Results: 375 IBD patients were analyzed: 48% had ulcerative colitis (UC). History of hospitalization concerned one third of IBD patients, and history of surgery 40% of Crohn’s disease patients (CD). Two thirds of IBD patients had active disease (disease activity was judged by the physician without using a validated tool or a score). The proportion of patients treated with anti-TNF therapy was significantly lower in UC (18.9%) than in CD (38.9 %; p<0.0001). Sixty per cent of UC patients were treated with 5-aminosalicylates as compared with 18.5% of in CD (p<0.0001). Among anti-TNF treated patients, only 4.5% were receiving concomitant immunomodulator. Half of IBD patients had a colonoscopy within the past year. Regarding colorectal cancer screening, random biopsies and chromoendoscopy were performed in 75% and 40% of cases, respectively. An endoscopic score was used for only 10% of IBD patients. About one third of IBD patients had imaging studies within the past year, MRI enterography representing about half of them. Abdominal CT was prescribed for 12% of IBD patients and abdominal ultrasound for only 7% of them. Conclusions: Many patients still have active disease in the biologics era despite an increasing use of immunosuppressive therapy, and the number of patients receiving combination therapy is low in private practice. Colonoscopy remains the gold standard to assess IBD even though MRI is increasingly used in these patients. Chromoendoscopy and endoscopy scores are not often used

Custom human endogenous retroviruses dedicated microarray identifies self-induced HERV-W family elements reactivated in testicular cancer upon methylation control

Endogenous retroviruses (ERVs) are an inherited part of the eukaryotic genomes, and represent ∼400 000 loci in the human genome. Human endogenous retroviruses (HERVs) can be divided into distinct families, composed of phylogenetically related but structurally heterogeneous elements. The majority of HERVs are silent in most physiological contexts, whereas a significant expression is observed in pathological contexts, such as cancers. Owing to their repetitive nature, few of the active HERV elements have been accurately identified. In addition, there are no criteria defining the active promoters among HERV long-terminal repeats (LTRs). Hence, it is difficult to understand the HERV (de)regulation mechanisms and their implication on the physiopathology of the host. We developed a microarray to specifically detect the LTR-containing transcripts from the HERV-H, HERV-E, HERV-W and HERV-K(HML-2) families. HERV transcriptome was analyzed in the placenta and seven normal/tumoral match-pair samples. We identified six HERV-W loci overexpressed in testicular cancer, including a usually placenta-restricted transcript of ERVWE1. For each locus, specific overexpression was confirmed by quantitative RT-PCR, and comparison of the activity of U3 versus U5 regions suggested a U3-promoted transcription coupled with 5′R initiation. The analysis of DNA from tumoral versus normal tissue revealed that hypomethylation of U3 promoters in tumors is a prerequisite for their activation

Microarray-Based Sketches of the HERV Transcriptome Landscape

Human endogenous retroviruses (HERVs) are spread throughout the genome and their long terminal repeats (LTRs) constitute a wide collection of putative regulatory sequences. Phylogenetic similarities and the profusion of integration sites, two inherent characteristics of transposable elements, make it difficult to study individual locus expression in a large-scale approach, and historically apart from some placental and testis-regulated elements, it was generally accepted that HERVs are silent due to epigenetic control. Herein, we have introduced a generic method aiming to optimally characterize individual loci associated with 25-mer probes by minimizing cross-hybridization risks. We therefore set up a microarray dedicated to a collection of 5,573 HERVs that can reasonably be assigned to a unique genomic position. We obtained a first view of the HERV transcriptome by using a composite panel of 40 normal and 39 tumor samples. The experiment showed that almost one third of the HERV repertoire is indeed transcribed. The HERV transcriptome follows tropism rules, is sensitive to the state of differentiation and, unexpectedly, seems not to correlate with the age of the HERV families. The probeset definition within the U3 and U5 regions was used to assign a function to some LTRs (i.e. promoter or polyA) and revealed that (i) autonomous active LTRs are broadly subjected to operational determinism (ii) the cellular gene density is substantially higher in the surrounding environment of active LTRs compared to silent LTRs and (iii) the configuration of neighboring cellular genes differs between active and silent LTRs, showing an approximately 8 kb zone upstream of promoter LTRs characterized by a drastic reduction in sense cellular genes. These gathered observations are discussed in terms of virus/host adaptive strategies, and together with the methods and tools developed for this purpose, this work paves the way for further HERV transcriptome projects

Propagation et rétrodiffusion d'un faisceau laser lissé dans un plasma de fusion thermonucléaire

PALAISEAU-Polytechnique (914772301) / SudocSudocFranceF

Le radon (environnement et santé)

Le radon et ses descendants constituent un facteur de risque important en matière de cancérogenèse pulmonaire. Les différents travaux effectués au Laboratoire de Pathologie Pulmonaire Expérimentale de Razès ont permis de démontrer que l'inhalation de radon et de ses produits de filiation sont à l'origine de cancers pulmonaires chez le rat. L'expérimentation animale a fourni également un modèle qui permet d'étudier la synergie avec d'autres cancérigènes pulmonaires et qui peut collaborer à l'études de molécules à visée anti-cancéreuses. Sur le plan épidémiologique, l'ensemble des données actuellement disponible confirme que le risque de cancer bronchique chez les mineurs s'accroît de façon linéaire avec l'exposition cumulée au radon. Le risque lié à l'exposition domestique existe, reste faible et inférieur à celui induit par le tabagisme actif mais est comparable au risque auquel expose le tabagisme passif. Il est indispensable de poursuivre les campagnes de réduction de l'exposition au radon dans les habitations existantes et à venir par des moyens simples, peu onéreux et efficaces telles que l'aération par ouverture des fenêtres et la vérification de l'état de la ventilation.LIMOGES-BU Médecine pharmacie (870852108) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Peut-on manger sans risques ? Acteurs et instruments de la sécurité sanitaire

International audienceL’ adoption, en 2002, de la General Food Law Regulation par l’Union européenne entendait tirer les conséquences des crises des années 1990, en particulier celle de la « vache folle » qui avait provoqué des morts et mis à mal la filière de la viande bovine en Europe.Près de vingt ans après la réorganisation de l’ensemble du dispositif de sécurité sanitaire des aliments, on peut se demander comment les acteurs publics et privés de ce secteur ont modifié leurs pratiques et leurs métiers, dans quelle mesure les consommateurs ont fait évoluer leurs comportements, et pour quelles raisons les crises sanitaires et les fraudes alimentaires se sont poursuivies. Ces questions restent un impensé des analyses sociologiques, une lacune que ce dossier contribue à combler

Intérêt du greffon graisseux ethmoïdal après nasalisation des cavités sinusiennes de la face lors du traitement chirurgical de la polypose naso-sinusienne

La polypose naso-sinusienne est une pathologie connue depuis l'antiquité. Pourtant sa physiopathologie et son traitement sont toujours sujets à controverse. Notre travail a consisté à étudier l'intérêt de la mise en place d'un greffon graisseux intra-ethmoïdal en fin de nasalisation des cavités sinusiennes de la face au travers d'une étude rétrospective sur 19 patients pris en charge au CHU de Limoges par le même praticien entre 1998 et 2006. Nous avons comparé nos résultats à ceux de la littérature ainsi qu'à ceux obtenus sur un groupe témoin traité dans la même période, par le même praticien, sans la mise en place d'un greffon graisseux.LIMOGES-BU Médecine pharmacie (870852108) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF