Brevican knockdown reduces late-stage glioma tumor aggressiveness

Growing evidence supports the important role of the tumor microenvironment (TME) in cancer biology. A defining aspect of the glioma TME is the unique composition and structure of its extracellular matrix (ECM), which enables tumor cells to overcome the inhibitory barriers of the adult central nervous system (CNS). In this way, the TME plays a role in glioma invasion and the cellular heterogeneity that distinguishes these tumors. Brain Enriched Hyaluronan Binding (BEHAB)/brevican (B/b), is a CNS-specific ECM constituent and is upregulated in the glioma TME. Previous studies have shown B/b exerts a pro-invasive function, suggesting it may represent a target to reduce glioma pathogenesis. Herein, we also provide evidence that B/b expression is enriched in the glioma initiating cell (GIC) niche. We demonstrate that B/b plays roles in the pathological progression, aggressiveness, and lethality of tumors derived from human GICs and traditional glioma cell lines. Interestingly, we found that B/b is not required to maintain the defining phenotypic properties of GICs and thereby acts primarily in late stages of glioma progression. This study suggests that the increased expression of B/b in the TME is a valuable therapeutic target for glioma.     

From neural signatures of emotional modulation to social cognition: individual differences in healthy volunteers and psychiatric participants

It is commonly assumed that early emotional signals provide relevant information for social cognition tasks. The goal of this study was to test the association between (a) cortical markers of face emotional processing and (b) social-cognitive measures, and also to build a model which can predict this association (a and b) in healthy volunteers as well as in different groups of psychiatric patients. Thus, we investigated the early cortical processing of emotional stimuli (N170, using a face and word valence task) and their relationship with the social-cognitive profiles (SCPs, indexed by measures of theory of mind, fluid intelligence, speed processing and executive functions). Group comparisons and individual differences were assessed among schizophrenia (SCZ) patients and their relatives, individuals with attention deficit hyperactivity disorder (ADHD), individuals with euthymic bipolar disorder (BD) and healthy participants (educational level, handedness, age and gender matched). Our results provide evidence of emotional N170 impairments in the affected groups (SCZ and relatives, ADHD and BD) as well as subtle group differences. Importantly, cortical processing of emotional stimuli predicted the SCP, as evidenced by a structural equation model analysis. This is the first study to report an association model of brain markers of emotional processing and SCP.     

Effects of early and late adverse experiences on morpho-quantitative characteristics of Sprague-Dawley rat spleen subjected to stress during adulthood

Morpho-quantitative studies of the spleen indicate that the proportions of the compartments and sub-compartments are stable in normal conditions. However, disorders due to stress can influence the number and function of the immune cells in this organ. The aim of this study was to determine, through the model of altering the early mother-infant bond and altering the late social bond through isolation, the effect on the morpho-quantitative characteristics of the spleen in adult Sprague-Dawley rats subjected to intermittent chronic stress in adulthood. Twenty-five newborn female rats were used, kept under the standardized lactation and feeding conditions. The rats were assigned randomly to 2 control groups (C1 and C2) and 3 experimental groups, exposed to early (E1), late (E2) or early-late (E3) adverse experiences and then subjected to intermittent chronic stress in adulthood (C2, E1, E2 and E3). The spleen of each animal was isolated and its morphometric characteristics were determined: volume density (Vv) of the red pulp, white pulp, marginal zone, splenic lymph nodule, periarterial lymphatic sheath and germinal center; areal number density (Na), surface density (Sv), number density (Nv), diameter (D) and total number of splenic lymph nodules. The mass of each compartment was also determined. A one-way analysis of variance (ANOVA) and Scheffé’s post hoc test were used for the statistical analysis. The p values were considered significant when they were less than 0.05 (*) and very significant at less than 0.025 (**). There were significant differences in the Vv of the red pulp, white pulp and their sub-compartments between the control and experimental groups. The white pulp increased significantly (P = 0.000) in E1, E2 and E3 compared to C1 and C2. The average Na and D values of the splenic lymph nodules were also higher in the experimental groups. The ANOVA for the mass of the spleen and the red pulp revealed no differences between the groups. The mass of the white pulp and its subcompartments was greater in the experimental groups. A higher proportion of white pulp in the experimental groups could be associated with an increase in spleen immune activity, with alterations depending on certain cell subsets. The chronic stress produced morpho-quantitative changes in the rat spleen, and these depended on the animal’s history of stress, whether it had been previously stressed or not, with further exposure to stress in adulthood.     

Melatonin down‐regulates MDM2 gene expression and enhances p53 acetylation in MCF‐7 cells

Compelling evidence demonstrated that melatonin increases p53 activity in cancer cells. p53 undergoes acetylation to be stabilized and activated for driving cells destined for apoptosis/growth inhibition. Over‐expression of p300 induces p53 acetylation, leading to cell growth arrest by increasing p21 expression. In turn, p53 activation is mainly regulated in the nucleus by MDM2. MDM2 also acts as E3 ubiquitin ligase, promoting the proteasome‐dependent p53 degradation. MDM2 entry into the nucleus is finely tuned by two different modulations: the ribosomal protein L11, acts by sequestering MDM2 in the cytosol, whereas the PI3K‐AkT‐dependent MDM2 phosphorylation is mandatory for MDM2 translocation across the nuclear membrane. In addition, MDM2‐dependent targeting of p53 is regulated in a nonlinear fashion by MDM2/MDMX interplay. Melatonin induces both cell growth inhibition and apoptosis in MCF7 breast cancer cells. We previously reported that this effect is associated with reduced MDM2 levels and increased p53 activity. Herein, we demonstrated that melatonin drastically down‐regulates MDM2 gene expression and inhibits MDM2 shuttling into the nucleus, given that melatonin increases L11 and inhibits Akt‐PI3K‐dependent MDM2 phosphorylation. Melatonin induces a 3‐fold increase in both MDMX and p300 levels, decreasing simultaneously Sirt1, a specific inhibitor of p300 activity. Consequently, melatonin‐treated cells display significantly higher values of both p53 and acetylated p53. Thus, a 15‐fold increase in p21 levels was observed in melatonin‐treated cancer cells. Our results provide evidence that melatonin enhances p53 acetylation by modulating the MDM2/MDMX/p300 pathway, disclosing new insights for understanding its anticancer effect.     

Evaluación formativa mediante el portafolio de 4 promociones de residentes de medicina de familia y comunitaria de la Unidad Docente de Murcia

ObjectiveTo evaluate the performance and quality of the 10 groups of training tasks envisaged in the portfolio training model undertaken by all residents of the Primary Care Teaching Unit in Murcia.DesignA cross-sectional study was conducted on the portfolios provided and completed by all residents in May 2011.ParticipantsAll residents who were in training at that time (131).MethodTen groups of training tasks were established from those recommended by the National Commission for the specialty. The performance of each one in each of the portfolios was evaluated, and the compliance for each training task was calculated. The quality of the performance of each of the tasks was given a score, 0 points (very poor) to 10 points (excellent).ResultsAs regards compliance, the tasks that were most performed were: filling in the Resident book correctly and using the resident skills guide, both with 99.24%, followed by reflection reports on the training visits. All tasks had a compliance rate higher than 67%. The mean percentage of compliance was 86.49%. All tasks obtained an average score greater than 7 (outstanding). The overall mean score was 7,8 points.ConclusionsThe level of perfomance of the tasks set out in the portfolio by the residents was very satisfying. It is necessary to continue working on improving the performance of the portfolio.