Analyse génotypique des cellules initiatrices de tumeurs exprimant CD133 dans le neuroblastome

Le neuroblastome (NB) est la tumeur solide extracranienne la plus fréquente et mortelle chez les jeunes enfants. Il se caractérise par une résistance à la chimiothérapie possiblement en partie dû à la présence de cellules initiatrices de tumeurs (TICs). Des études ont mis en évidence le rôle de CD133 comme un marqueur des TICs dans divers types de cancers. Les buts de notre travail étaient d’abord de démontrer les vertus de TICs des cellules exprimant CD133 et ensuite, en utilisant une analyse globale du génome avec des polymorphismes nucléotidiques simples (SNPs), d’effectuer une analyse différentielle entre les TICs et les autres cellules du NB afin d’en identifier les anomalies génétiques spécifiques. Des lignées cellulaires de NB ont été triées par cytométrie de flux afin d’obtenir deux populations: une enrichie en CD133 (CD133high), l’autre faible en CD133 (CD133low). Afin de déterminer si ces populations cellulaires présentent des propriétés de TICs, des essais sur les neurosphères, les colonies en agar mou et les injections orthotopiques de 500 cellules sélectionnées dans 11 souris ont été réalisées. Après une isolation de l’ADN des populations sélectionnées, nous avons effectué une analyse génotypique par SNP utilisant les puces « Affymetrix Genome-Wide Human SNP Array 6.0 ». Pour vérifier l’expression des gènes identifiés, des Western Blots ont été réalisés. Nos résultats ont démontré que la population CD133 avait des propriétés de TICs in vitro et in vivo. L’analyse génotypique différentielle a permis d’identifier deux régions communes (16p13.3 and 19p13.3) dans la population CD133high ayant des gains et deux autres régions (16q12.1 and 21q21.3) dans la population CD133low possédant des pertes d’hétérozygoties (LOH). Aucune perte n’a été observée. Parmi les gènes étudiés, l’expression protéique d’éphrine-A2 était corrélée à celle de CD133 dans 6 tumeurs et 2 lignées cellulaires de NB. De plus, l’augmentation de la concentration d’anticorps anti-éphrine-A2 dans le milieu diminue la taille des neurosphères. Ainsi, la population CD133high, qui a des vertus de TICs, possède des caractéristiques génotypiques différentes par rapport à celle CD133low. La présence d’éphrine-A2 dans les cellules exprimant CD133 souligne son importance dans le développement des TICs. Ces résultats suggèrent la présence de potentielle cible pour de nouvelles thérapeutiques ciblant les TICs mise en évidence par l’étude génomique.Neuroblastoma (NB) is the most common and deadly extracranial solid tumor of childhood characterized by a resistance to chemotherapy possibly due to the presence of tumor initiating cells (TICs). Studies showed the role of CD133 as a marker of TICs in various types of cancers. Our goals were first to demonstrate the stemness of TICs expressing CD133 and then, using a global genomic analysis with single nucleotide polymorphism (SNPs), to perform a differential analysis between TICs and other cells of NB to identify the specific genetic abnormalities. NB cell lines were sorted by flow cytometry to obtain two populations: one enriched in CD133 (CD133high), the other low in CD133 (CD133low). To determine whether these cell populations have TICs properties, we test the ability of cells to form either neurosphères or, colonies in soft agar and we also test their carcinogenic properties by orthotopic injections of 500 selected cells in 11 mice. After a DNA extraction on selected populations, a differential genotyping analysis has been made with Affymetrix Genome-Wide Human SNP Array 6.0. To verify the expression of the genes identified, Western blots had been made. Our results have demonstrated that CD133high population presented TICs properties in vitro and in vivo. The differential genotyping analysis allowed identifying two gains common regions (16p13.3 and 19p13.3) in CD133high population and two others loss of heterozygosity (LOH) (16q12.1 and 21q21.3) in CD133low population . No losses were observed. Among the genes studied, ephrin-A2 protein expression was correlated to CD133 expression in 6 NB tumors and 2 NB cell lines. Also, ephrin-A2’s increased concentration influenced the neurospheres by decreasing their size. Thereby, CD133high population, which had TICs properties, possess different genotyping characteristics compared to CD133low population. The presence of ephrine-A2 in cells expressing CD133 emphasizes its importance in the development of TICs. These results suggest the presence of potential target for new therapies targeting the TICs demonstrated by the genomic study

Expression of CD133 in differentiated thyroid cancer of young patients

CD133 expression in cancer is frequently associated with poor outcome. Thyroid carcinomas are rare in childhood and adolescence and are associated with a higher risk of recurrence and more metastases than the adult tumours. The aim of the study was to assess whether the expression of CD133 in thyroid carcinomas of children, adolescents and young adults was correlated with clinical prognostic factors

Canagliflozin and renal outcomes in type 2 diabetes and nephropathy

BACKGROUND Type 2 diabetes mellitus is the leading cause of kidney failure worldwide, but few effective long-term treatments are available. In cardiovascular trials of inhibitors of sodium–glucose cotransporter 2 (SGLT2), exploratory results have suggested that such drugs may improve renal outcomes in patients with type 2 diabetes. METHODS In this double-blind, randomized trial, we assigned patients with type 2 diabetes and albuminuric chronic kidney disease to receive canagliflozin, an oral SGLT2 inhibitor, at a dose of 100 mg daily or placebo. All the patients had an estimated glomerular filtration rate (GFR) of 30 to <90 ml per minute per 1.73 m2 of body-surface area and albuminuria (ratio of albumin [mg] to creatinine [g], >300 to 5000) and were treated with renin–angiotensin system blockade. The primary outcome was a composite of end-stage kidney disease (dialysis, transplantation, or a sustained estimated GFR of <15 ml per minute per 1.73 m2), a doubling of the serum creatinine level, or death from renal or cardiovascular causes. Prespecified secondary outcomes were tested hierarchically. RESULTS The trial was stopped early after a planned interim analysis on the recommendation of the data and safety monitoring committee. At that time, 4401 patients had undergone randomization, with a median follow-up of 2.62 years. The relative risk of the primary outcome was 30% lower in the canagliflozin group than in the placebo group, with event rates of 43.2 and 61.2 per 1000 patient-years, respectively (hazard ratio, 0.70; 95% confidence interval [CI], 0.59 to 0.82; P=0.00001). The relative risk of the renal-specific composite of end-stage kidney disease, a doubling of the creatinine level, or death from renal causes was lower by 34% (hazard ratio, 0.66; 95% CI, 0.53 to 0.81; P<0.001), and the relative risk of end-stage kidney disease was lower by 32% (hazard ratio, 0.68; 95% CI, 0.54 to 0.86; P=0.002). The canagliflozin group also had a lower risk of cardiovascular death, myocardial infarction, or stroke (hazard ratio, 0.80; 95% CI, 0.67 to 0.95; P=0.01) and hospitalization for heart failure (hazard ratio, 0.61; 95% CI, 0.47 to 0.80; P<0.001). There were no significant differences in rates of amputation or fracture. CONCLUSIONS In patients with type 2 diabetes and kidney disease, the risk of kidney failure and cardiovascular events was lower in the canagliflozin group than in the placebo group at a median follow-up of 2.62 years

Facteurs prédictifs des coûts de médicaments pour les enfants hospitalisés dans un hôpital mère–enfant universitaire

ABSTRACTThe goal of this study was to determine the drug costs for pediatric inpatients at a mother–child centre and to identify predictive factors for these costs. Data on drug costs for all hospital admissions at the Hôpital Sainte-Justine during fiscal years 2000/2001, 2001/2002, and 2002/2003 were imported from 3 computer systems and analyzed by multiple regression with blocks of variables. The variables were introduced by block, according to conceptual similarities, in a predetermined order, and their respective contributions were calculated in relation to the total variance of the model. The episodes of care in this study covered a total of 25 248 patient-years and total drug expenditures of $10,612,448 for the 3 fiscal years. The drug costs included in this analysis represented 82.5$ CA pour les trois exercices financiers. Les données de coûts en médicaments inclus dans notre analyse représentent respectivement 82,5 %, 88,2 % et 80,2 % des coûts totaux en médicaments pour chaque exercice financier. Le modèle proposé permet d’expliquer 32,9 % de la variance des coûts de médicaments par patient. De fait, deux blocs permettent à eux seuls d’expliquer 27,9 % de la variance des coûts, soit le niveau de gravité clinique (14,3 %) et les catégories majeures de diagnostic (13,6 %). Il existe peu de données publiées sur les coûts de médicaments en pédiatrie et sur les facteurs pouvant contribuer à planifier ces dépenses en établissement de santé. Notre étude présente un modèle de régression linéaire multiple permettant d’expliquer 33 % des coûts en médicaments. D’autres études sont nécessaires afin de développer un modèle permettant de prédire de façon plus complète l’évolution des coûts en médicaments pour les clientèles en établissement de santé

Distribution des bactéries pathogènes dans les sols évaluée par PCR quantitative en temps réel

National audienc

A web-based tailored nursing intervention to support illness management in patients hospitalized for an acute coronary syndrome : a pilot study

Background: Illness management after an acute coronary syndrome (ACS) is crucial to prevent cardiac complications, to foster participation in a cardiac rehabilitation (CR) program, and to optimize recovery. Web-based tailored interventions have the potential to provide individualized information and counseling to optimize patient’s illness management after hospital discharge. Objective: We aimed to assess the feasibility and acceptability of a Web-based tailored intervention (TAVIE@COEUR) designed to improve illness management in patients hospitalized for an ACS. Illness management outcomes were operationalized by self-care, medication adherence, anxiety management, cardiac risk factors reduction, and enrollment in a CR program. Methods: This posttest pilot study was conducted with one group (N=30) of patients hospitalized for an ACS on the coronary care unit of a tertiary cardiology center. TAVIE@COEUR comprises three Web-based sessions, with a duration ranging from 10 to 45 min and is structured around an algorithm to allow the tailoring of the intervention to different pathways according to patients’ responses to questions. TAVIE@COEUR includes 90 pages, 85 videos, and 47 PDF documents divided across session 1 (S1), session 2 (S2), and session 3 (S3). These sessions concern self-care and self-observation skills related to medication-taking (S1), emotional control and problem-solving skills (S2), and social skills and interacting with health professionals (S3). Throughout the videos, a virtual nurse (providing the intervention virtually) guides the participants in the acquisition of self-care skills. Patients completed S1 of TAVIE@COEUR before hospital discharge and were asked to complete S2 and S3 within 2 weeks after discharge. Feasibility indicators were extracted from the TAVIE@COEUR system. Data regarding acceptability (satisfaction and appreciation of the platform) and preliminary effect (self-care, medication adherence, anxiety management, risk factor reduction, and CR enrollment) were assessed through questionnaires at 1 month following discharge. Preliminary effect was assessed by comparing baseline and 1-month illness management variables. Results: Of the 30 participants, 20 completed S1, 10 completed S2, and 5 completed S3. Good acceptability scores were observed for ease of navigation (mean=3.58, standard deviation [SD]=0.70; scale=0-4), ease of understanding (mean=3.46, SD=0.63; scale=0-4), and applicability (mean=3.55, SD=0.74; scale=0-4). The lowest acceptability scores were observed for information tailoring (mean=2.93, SD=0.68; scale=0-4) and individual relevance (mean=2.56, SD=0.96; scale=0-4). With regard to preliminary effect, we observed an overall self-care at 1 month following discharge score higher than at baseline (mean at 1 month=54.07, SD=3.99 vs mean at baseline=49.09, SD=6.92; scale-0-60). Conclusions: Although participants reported general satisfaction and appreciation of TAVIE@COEUR, acceptability and feasibility results show the need for further development of the Web-based intervention to enhance its tailoring before undertaking a full-fledged randomized controlled trial. This may be accomplished by optimizing the adaptability of TAVIE@COEUR to patients’ knowledge, needs, interests, individual capabilities, and emotional and cognitive responses during session completion

Additional file 4: Figure S4. of Autophagy is associated with chemoresistance in neuroblastoma

Effect of ATG5 knockdown xenografts on tumor growth. (11/12) NSG Mice developed xenograft tumor from s.c injection of 5.106 sheGFP cells and only (3/12) from shATG5 cells (Table A). When tumor reached 200 mm3, mice were administered vincristine (0.4 mg/kg/day) or vehicle (saline) for 5 days. Progression of tumor volume was followed in each group. Each data point represents the mean 6 ± SE tumor volume for sheGFP cells and 1 or 2 for shAtg5 cells. At day 6, Tumors size from shATG5 cells were reduced compared with tumors from eGFP (B). Also, tumors from shATG5 cells were more sensitive to vincristine comparing to control cells. Immunohistochemistry was performed on the sections of tumors developed in the mouse model. with LC3 antibody and showed a high expression of LC3 II in control cells and a very low in cells ATG5 knockdown as well as treated (b, d) or not treated (a, c) (C). (PDF 259 kb