Regulation of CO2 by the sea in areas around Latin America in a context of climate change.

Anthropogenic activities are increasing the atmospheric carbon dioxide (CO2); around a third of the CO2 emitted by these activities has been taken up by the ocean. Nevertheless, this marine ecosystem service of regulation remains largely invisible to society, and not enough is known about regional differences and trends in sea-air CO2 fluxes (FCO2), especially in the Southern Hemisphere. The objectives of this work were as follows: first to put values of FCO2 integrated over the exclusive economic zones (EEZ) of five Latin-American countries (Argentina, Brazil, Mexico, Peru, and Venezuela) into perspective regarding total country-level greenhouse gases (GHG) emissions. Second, to assess the variability of two main biological factors affecting FCO2 at marine ecological time series (METS) in these areas. FCO2 over the EEZs were estimated using the NEMO model, and GHG emissions were taken from reports to the UN Framework Convention on Climate Change. For each METS, the variability in phytoplankton biomass (indexed by chlorophyll-a concentration, Chla) and abundance of different cell sizes (phy-size) were analyzed at two time periods (2000-2015 and 2007-2015). Estimates of FCO2 at the analyzed EEZs showed high variability among each other and non-negligible values in the context of greenhouse gas emissions. The trends observed at the METS indicated, in some cases, an increase in Chla (e.g., EPEA-Argentina) and a decrease in others (e.g., IMARPE-Peru). Evidence of increasing populations of small size-phytoplankton was observed (e.g., EPEA-Argentina, Ensenada-Mexico), which would affect the carbon export to the deep ocean. These results highlight the relevance of ocean health and its ecosystem service of regulation when discussing carbon net emissions and budgets.

The three α1-adrenoceptor subtypes show different spatio-temporal mechanisms of internalization and ERK1/2 phosphorylation.

We analyzed the kinetic and spatial patterns characterizing activation of the MAP kinases ERK 1 and 2 (ERK1/2) by the three α1-adrenoceptor (α1-AR) subtypes in HEK293 cells and the contribution of two different pathways to ERK1/2 phosphorylation: protein kinase C (PKC)-dependent ERK1/2 activation and internalization-dependent ERK1/2 activation. The different pathways of phenylephrine induced ERK phosphorylation were determined by western blot, using the PKC inhibitor Ro 31-8425, the receptor internalization inhibitor concanavalin A and the siRNA targeting ß-arrestin 2. Receptor internalization properties were studied using CypHer5 technology and VSV-G epitope-tagged receptors. Activation of α1A- and α1B-ARs by phenylephrine elicited rapid ERK1/2 phosphorylation that was directed to the nucleus and inhibited by Ro 31-8425. Concomitant with phenylephrine induced receptor internalization α1A-AR, but not α1B-AR, produced a maintained and PKC-independent ERK phosphorylation, which was restricted to the cytosol and inhibited by ß-arrestin 2 knockdown or concanavalin A treatment. α1D-AR displayed constitutive ERK phosphorylation, which was reduced by incubation with prazosin or the selective α1D antagonist BMY7378. Following activation by phenylephrine, α1D-AR elicited rapid, transient ERK1/2 phosphorylation that was restricted to the cytosol and not inhibited by Ro 31-8425. Internalization of the α1D-AR subtype was not observed via CypHer5 technology. The three α1-AR subtypes present different spatio-temporal patterns of receptor internalization, and only α1A-AR stimulation translates to a late, sustained ERK1/2 phosphorylation that is restricted to the cytosol and dependent on ß-arrestin 2 mediated internalization.

Spanish human proteome project: dissection of chromosome 16.

The Chromosome 16 Consortium forms part of the Human Proteome Project that aims to develop an entire map of the proteins encoded by the human genome following a chromosome-centric strategy (C-HPP) to make progress in the understanding of human biology in health and disease (B/D-HPP). A Spanish consortium of 16 laboratories was organized into five working groups: Protein/Antibody microarrays, protein expression and Peptide Standard, S/MRM, Protein Sequencing, Bioinformatics and Clinical healthcare, and Biobanking. The project is conceived on a multicenter configuration, assuming the standards and integration procedures already available in ProteoRed-ISCIII, which is encompassed within HUPO initiatives. The products of the 870 protein coding genes in chromosome 16 were analyzed in Jurkat T lymphocyte cells, MCF-7 epithelial cells, and the CCD18 fibroblast cell line as it is theoretically expected that most chromosome 16 protein coding genes are expressed in at least one of these. The transcriptome and proteome of these cell lines was studied using gene expression microarray and shotgun proteomics approaches, indicating an ample coverage of chromosome 16. With regard to the B/D section, the main research areas have been adopted and a biobanking initiative has been designed to optimize methods for sample collection, management, and storage under normalized conditions and to define QC standards. The general strategy of the Chr-16 HPP and the current state of the different initiatives are discussed.

Distribution of segmental chromosomal alterations in neuroblastoma.

BACKGROUND: Neuroblastoma (NB) is a heterogeneous tumor with extremely diverse prognosis according to clinical and genetic factors such as specific combinations of chromosomal imbalances. METHODS: Molecular karyotyping data from a national neuroblastic tumor database of 155 NB samples were analyzed and related to clinical data. RESULTS: Segmental chromosomal alterations (SCA) were detected in 102 NB, whereas 45 only displayed numerical alterations. Incidence of SCA was higher in stage M (92%) and MYCN amplified (MNA) NB (96%). Presence of SCA was associated with older age, especially 1q gain and 3p deletion. 96% of the deaths were observed in the SCA group and 85% of the relapsed NB contained SCA. The alteration most commonly associated with a higher number of other segmental rearrangements was 11q deletion, followed by 4p deletion. Whole-chromosome 19 gain was associated with lower stages, absence of SCA and better outcome. CONCLUSIONS: SCA are not randomly distributed and are concentrated on recurrent chromosomes. The most frequently affected chromosomes identify prognostic factors in specific risk groups. SCA are associated with older age and MNA. We have identified a small subset of patients with better outcome that share whole-chromosome 19 numeric gain, suggesting its use as a prognostic biomarker in NB.

Precision medicine in Ewing sarcoma: a translational point of view.

Ewing sarcoma is a rare tumor that arises in bones of children and teenagers but, in 15% of the patients it is presented as a primary soft tissue tumor. Balanced reciprocal chimeric translocation t(11;22)(q24;q12), which encodes an oncogenic protein fusion (EWSR1/FLI1), is the most generalized and characteristic molecular event. Using conventional treatments, (chemotherapy, surgery and radiotherapy) long-term overall survival rate is 30% for patients with disseminated disease and 65-75% for patients with localized tumors. Urgent new effective drug development is a challenge. This review summarizes the preclinical and clinical investigational knowledge about prognostic and targetable biomarkers in Ewing sarcoma, finally suggesting a workflow for precision medicine committees.

Li-Fraumeni syndrome heterogeneity.

Clinical variability is commonly seen in Li-Fraumeni syndrome. Phenotypic heterogeneity is present among different families affected by the same pathogenic variant in TP53 gene and among members of the same family. However, causes of this huge clinical spectrum have not been studied in depth. TP53 type mutation, polymorphic variants in TP53 gene or in TP53-related genes, copy number variations in particular regions, and/or epigenetic deregulation of TP53 expression might be responsible for clinical heterogeneity. In this review, recent advances in the understanding of genetic and epigenetic aspects influencing Li-Fraumeni phenotype are discussed.

Identification of TNF-alpha and MMP-9 as potential baseline predictive serum markers of sunitinib activity in patients with renal cell carcinoma using a human cytokine array.

BACKGROUND: Several drugs are available to treat metastatic renal-cell carcinoma (MRCC), and predictive markers to identify the most adequate treatment for each patient are needed. Our objective was to identify potential predictive markers of sunitinib activity in MRCC. METHODS: We collected sequential serum samples from 31 patients treated with sunitinib. Sera of six patients with extreme phenotypes of either marked responses or clear progressions were analysed with a Human Cytokine Array which evaluates 174 cytokines before and after treatment. Variations in cytokine signal intensity were compared between both groups and the most relevant cytokines were assessed by ELISA in all the patients. RESULTS: Twenty-seven of the 174 cytokines varied significantly between both groups. Five of them (TNF-alpha, MMP-9, ICAM-1, BDNF and SDF-1) were assessed by ELISA in 21 evaluable patients. TNF-alpha and MMP-9 baseline levels were significantly increased in non-responders and significantly associated with reduced overall survival and time-to-progression, respectively. The area under the ROC curves for TNF-alpha and MMP-9 as predictive markers of sunitinib activity were 0.83 and 0.77. CONCLUSION: Baseline levels of TNF-alpha and MMP-9 warrant further study as predictive markers of sunitinib activity in MRCC. Selection of patients with extreme phenotypes seems a valid method to identify potential predictive factors of response.

Quadriceps muscle characteristics and subcutaneous fat assessed by ultrasound and relationship with function in patients with knee osteoarthritis awaiting knee arthroplasty.

BACKGROUND: Patients with severe knee osteoarthritis are evaluated for total knee replacement (TKR), whose main indications are persistent pain and severe functional limitations substantially affecting mobility. However, evaluation of pain intensity and functional disability is difficult to standardize. OBJECTIVE: To evaluate the relationship between quadriceps muscle thickness (QMT) and quality; the QMT and subcutaneous fat thickness (SFT) and QMT and function in patients with knee OA on a waiting list for TKR. METHODS: Cross-sectional study in consecutively-enrolled patients. Variables: SFT, QMT and rectus femoris muscle quality, assessed by echointensity (EI). Function by the Timed Up & Go Test (TUG); sociodemographic and clinical variables and physical activity were determined. Karl Pearson correlations and multiple linear regression were used. RESULTS: 61 patients (45 female, mean age 69.7 years [SD 7.2], mean BMI 33.0 [SD 5.7], mean comorbidities 3.3 [SD 2.0], 52.5% regular physical activity) were studied. Mean TUG was 15.1 (SD 6.1). Variables retained in the regression model explained 36% of variability in the TUG. Greater muscle content (percentage) (r = -0,291) was associated with better TUG scores (p = 0.001). Greater muscle EI was negatively (r = -0,364) associated with function (p = 0.006). Older age was associated with worse TUG scores while regular physical activity was associated with better TUG scores (p = 0.001 and p = 0.008, respectively). CONCLUSIONS: A higher percentage of quadriceps muscle and better muscle quality (lower EI) was associated with better function. Age and exercise levels influenced function. Ultrasound may provide.

Retinoblastoma: towards an earlier diagnosis. / Retinoblastoma: hacia un diagnóstico más precoz.

OBJECTIVES: The number of enucleations and visual sequels due to retinoblastoma is high. The aim of this study was to evaluate the different diagnostic aspects and propose strategies that might improve the clinical management of this condition. METHOD: A retrospective study was conducted on 38 patients with retinoblastoma studied genetically (29 unilateral, 9 bilateral). The evaluation included: age of onset, clinical signs, and time since onset, number of enucleations, time to diagnosis, and survival at 5 years. RESULTS: Leukocoria was the main clinical sign (present in 90% of cases). The mean diagnostic delay was 3.2 months. Among the unilateral cases, the eyes were enucleated in 76%, and 55% in the bilateral forms. Only one death was found among the 25 patients followed-up for at least 5 years. CONCLUSIONS: Retinoblastoma diagnostic and treatment strategies need to be updated. Good coordination between paediatricians and ophthalmologists is essential for this. Its management in reference centres, which have the necessary technology and experience, should contribute to increase the rate of organ preservation.

ODZ1 allows glioblastoma to sustain invasiveness through a Myc-dependent transcriptional upregulation of RhoA.

Long-term survival remains low for most patients with glioblastoma (GBM), which reveals the need for markers of disease outcome and novel therapeutic targets. We describe that ODZ1 (also known as TENM1), a type II transmembrane protein involved in fetal brain development, plays a crucial role in the invasion of GBM cells. Differentiation of glioblastoma stem-like cells drives the nuclear translocation of an intracellular fragment of ODZ1 through proteolytic cleavage by signal peptide peptidase-like 2a. The intracellular fragment of ODZ1 promotes cytoskeletal remodelling of GBM cells and invasion of the surrounding environment both in vitro and in vivo. Absence of ODZ1 by gene deletion or downregulation of ODZ1 by small interfering RNAs drastically reduces the invasive capacity of GBM cells. This activity is mediated by an ODZ1-triggered transcriptional pathway, through the E-box binding Myc protein, that promotes the expression and activation of Ras homolog family member A (RhoA) and subsequent activation of Rho-associated, coiled-coil containing protein kinase (ROCK). Overexpression of ODZ1 in GBM cells reduced survival of xenografted mice. Consistently, analysis of 122 GBM tumour samples revealed that the number of ODZ1-positive cells inversely correlated with overall and progression-free survival. Our findings establish a novel marker of invading GBM cells and consequently a potential marker of disease progression and a therapeutic target in GBM.

Metastatic neuroblastoma in infants: are survival rates excellent only within the stringent framework of clinical trials?

INTRODUCTION: SIOPEN INES protocol yielded excellent 5-year survival rates for MYCN-non-amplified metastatic neuroblastoma. Patients deemed ineligible due to lack or delay of MYCN status or late registration were treated, but not included in the study. Our goal was to analyse survival at 10 years among the whole population. MATERIALS AND METHODS: Italian and Spanish metastatic INES patients' data are reported. SPSS 20.0 was used for statistical analysis. RESULTS: Among 98 infants, 27 had events and 19 died, while 79 were disease free. Five- and 10-year event-free survival (EFS) were 73 and 70 %, and overall survival (OS) was 81 and 74 %, respectively. MYCN status was significant for EFS, but not for OS in multivariate analysis. CONCLUSIONS: The survival rates of patients who complied with all the inclusion criteria for INES trials are higher compared to those that included also not registered patients. Five-year EFS and OS for INES 99.2 were 87.8 and 95.7 %, while our stage 4s population obtained 78 and 87 %. Concerning 99.3, 5-year EFS and OS were 86.7 and 95.6 %, while for stage 4 we registered 61 and 68 %. MYCN amplification had a strong impact on prognosis and therefore we consider it unacceptable that many patients were not studied for MYCN and probably inadequately treated. Ten-year survival rates were shown to decrease: EFS from 73 to 70 % and OS from 81 to 74 %, indicating a risk of late events, particularly in stage 4s. Population-based registries like European ENCCA WP 11-task 11 will possibly clarify these data.

Paediatric tumour boards in Spain: a national survey.

PURPOSE: Multidisciplinary tumour boards (MDTs) are conducted worldwide for the management of patients with cancer, and they deliver a higher standard of care by simultaneously involving different specialists in diagnosis and treatment planning. However, information of paediatric MDTs functioning is scarce. A pilot study was conducted in Spain in the frame of the European Expert Paediatric Oncology Reference Network for Diagnostics and Treatment (ExPO-r-Net). METHODS: A specific questionnaire was designed regarding various features of MDT practice. Data collected included information on the centres and the team, infrastructure for meetings, MDT organization/logistics and clinical decision-making. The survey was distributed to all Paediatric Oncology Units that register patients in the Spanish Registry of Childhood Tumours (RETI-SEHOP). RESULTS: 32 out of 43 contacted centres responded the questionnaire (74 % response rate; 88 % response rate for centres with >25 new patients/year). All units with >25 new patients/year have a dedicated Paediatric MDT compared to 76 % of units with ≤25 new patients/year. MDTs should be improved at institutional level by clear protected time in service planning for all specialists involved, incentives for attendance and attendance registration. Clinical decision-making process and follow-up of recommendation adherence should be assessed and potential legal responsibilities for physicians participating in Tumour Board defined. Network collaboration through virtual MDTs, using available videoconferencing tools, is an opportunity to share expertise among centres.

New resources for genetic studies in Populus nigra: genome-wide SNP discovery and development of a 12k Infinium array.

Whole genome resequencing of 51 Populus nigra (L.) individuals from across Western Europe was performed using Illumina platforms. A total number of 1 878 727 SNPs distributed along the P. nigra reference sequence were identified. The SNP calling accuracy was validated with Sanger sequencing. SNPs were selected within 14 previously identified QTL regions, 2916 expressional candidate genes related to rust resistance, wood properties, water-use efficiency and bud phenology and 1732 genes randomly spread across the genome. Over 10 000 SNPs were selected for the construction of a 12k Infinium Bead-Chip array dedicated to association mapping. The SNP genotyping assay was performed with 888 P. nigra individuals. The genotyping success rate was 91%. Our high success rate was due to the discovery panel design and the stringent parameters applied for SNP calling and selection. In the same set of P. nigra genotypes, linkage disequilibrium throughout the genome decayed on average within 5-7 kb to half of its maximum value. As an application test, ADMIXTURE analysis was performed with a selection of 600 SNPs spread throughout the genome and 706 individuals collected along 12 river basins. The admixture pattern was consistent with genetic diversity revealed by neutral markers and the geographical distribution of the populations. These newly developed SNP resources and genotyping array provide a valuable tool for population genetic studies and identification of QTLs through natural-population based genetic association studies in P. nigra.

Concomitant histone deacetylase and phosphodiesterase 5 inhibition synergistically prevents the disruption in synaptic plasticity and it reverses cognitive impairment in a mouse model of Alzheimer's disease.

BACKGROUND: Given the implication of histone acetylation in memory processes, histone deacetylase inhibitors (HDACIs) have been postulated as potential modulators of cognitive impairment in Alzheimer's disease (AD). However, dose-dependent side effects have been described in patients with the currently available broad-spectrum HDACIs, explaining why their therapeutic potential has not been realized for chronic diseases. Here, by simultaneously targeting two independent enzyme activities, histone deacetylase (HDAC) and phosphodiesterase-5 (PDE5), we propose a novel mode of inhibitory action that might increase the therapeutic specificity of HDACIs. RESULTS: The combination of vorinostat, a pan-HDACI, and tadalafil, a PDE5 inhibitor, rescued the long-term potentiation impaired in slices from APP/PS1 mice. When administered in vivo, the combination of these drugs alleviated the cognitive deficits in AD mice, as well as the amyloid and tau pathology, and it reversed the reduced dendritic spine density on hippocampal neurons. Significantly, the combination of vorinostat and tadalafil was more effective than each drug alone, both against the symptoms and in terms of disease modification, and importantly, these effects persisted after a 4-week washout period. CONCLUSIONS: The results highlight the pharmacological potential of a combination of molecules that inhibit HDAC and PDE5 as a therapeutic approach for AD treatment.

Frequency, causes, and outcome of home ventilator failure.

STUDY OBJECTIVES: The safety of home ventilators has been questioned. We collected data to study the following: frequency of home ventilator failure, apparent causes for the failure or malfunction, and adverse consequences following the failure. STUDY DESIGN: Information on all requests to correct home ventilator failures reported to a home respiratory equipment vendor was collected prospectively between November 1991, and November 1992. PATIENTS: There were 150 ventilator-assisted patients aged 2 to 77 years; 44 were < or = 18 years. They received 841,234 h of home mechanical ventilation (average, 15.4 h/d per ventilator-assisted patient). RESULTS: There were 189 reports of home ventilator failure. Defective equipment or mechanical failure was found in only 39% (73 reports), equivalent to one home ventilator failure for every 1.25 years of continuous use. Other causes of ventilator failure included the following: improper care, damage, or tampering with the ventilator by caregivers (13%), functional equipment improperly used by caregivers (30%), and equipment functional but the patient's condition changed, mimicking ventilator failure (3%). No problem could be identified in 16%. The following actions were required: ventilator replacement (44%), repair of a defective part (6%), replacement of a functioning ventilator for psychological comfort (14%), ventilator adjustments made (21%), caregiver reeducation (7%), caregiver anxiety or distress reduced (3%), and no action required (4%). Hospitalization was required only in two cases (1%). No adverse outcomes, deaths, or serious injuries were associated with home ventilator failure. CONCLUSIONS: We conclude that in 150 patients requiring home mechanical ventilation, ventilator failure occurred relatively infrequently, and there were no adverse outcomes as a result of equipment failure at home. We speculate that equipment failure is not a frequent or serious problem for ventilator-assisted patients treated at home.

[Intracranial hemorrhage following second thrombolytic treatment of myocardial reinfarction]. / Hemorragia intracraneal tras un segundo tratamiento trombolítico por reinfarto de miocardio.

Intracranial hemorrhage was observed in a man, aged 66, after a second thrombolytic treatment due to myocardial reinfarction. The patient presented no potential risk factors which have often been associated to intracranial hemorrhage whereas no complications had occurred when thrombolytic therapy was given some months before because of the first infarction. This report emphasizes that a previous thrombolytic treatment with no secondary effects involves no lack of intracranial hemorrhage risk for a second thrombolysis. More research is needed in order to elucidate intracranial hemorrhage mechanisms associated to thrombolytic therapy.

[Inflammation study in unstable angina and myocardial infarction without ST segment elevation. Value of ultra-sensitive C-reactive protein]. / Estado inflamatorio en el angor inestable e infarto de miocardio sin elevación del segmento ST. Valor de la proteína C-reactiva ultrasensible.

OBJECTIVES: To analyse the inflammatory state in Acute Coronary Syndromes without ST-segment elevation by means of the value of the High-sensitivity C-reactive protein and other markers of inflammation. To assess if there are differences between unstable angina and myocardial infarction and if it has prognostic value of cardiovascular complications during one year follow up. METHODS: 61 patients diagnosed of Acute Coronary Syndrome without ST-segment elevation were studied: mean age of 67 +/- 11 years old, 26% women. The value of high-sensitivity C-reactive protein and other inflammatory markers (leukocytes and fibrinogen) were analysed and were compared in those patients with unstable angina versus myocardial infarction without ST elevation. Follow up during one year of cardiovascular complications (death with cardiac origin, infarction, refractory ischemia or rehospitalization because of cardiovascular cause) and its relation with the inflammatory markers. RESULTS: 75% of the patients showed increased levels of High-sensitivity C-reactive protein (> 2 mg/l). 47 patients (77%) were diagnosed of Infarction without ST elevation and the remainders of Unstable Angina. There were no statistically significant differences between subgroups, neither in the median value of the C-reactive protein: 4.49 mg/l in infarction versus 4.5 mg/l in Angina (p = ns) nor in the percentage of patients with high levels of C-reactive protein (77% in infarction versus 71% in Angina). With regard to the other inflammatory markers (fibrinogen and leukocytes) no differences between subgroups were found. None of the inflammatory markers showed predictive value about the appearance of the composite end-point during one year follow up. CONCLUSIONS: The high-sensitivity C-reactive protein is elevated in patients with Acute coronary syndromes without ST-segment elevation, but no difference in the inflammatory state of patients with unstable angina versus myocardial infarction without ST elevation was found. In our series, these markers were not related with the risk of cardiovascular complications.

Different ß-adrenoceptor subtypes coupling to cAMP or NO/cGMP pathways: implications in the relaxant response of rat conductance and resistance vessels.

BACKGROUND AND PURPOSE: To analyse the relative contribution of ß1 -, ß2 - and ß3 -adrenoceptors (Adrb) to vasodilatation in conductance and resistance vessels, assessing the role of cAMP and/or NO/cGMP signalling pathways. EXPERIMENTAL APPROACH: Rat mesenteric resistance artery (MRA) and aorta were used to analyse the Adrb expression by real-time-PCR and immunohistochemistry, and for the pharmacological characterization of Adrb-mediated activity by wire myography and tissue nucleotide accumulation. KEY RESULTS: The mRNAs and protein for all Adrb were identified in endothelium and/or smooth muscle cells (SMCs) in both vessels. In MRA, Adrb1 signalled through cAMP, Adrb3 through both cAMP and cGMP, but Adrb2, did not activate nucleotide formation; isoprenaline relaxation was inhibited by propranolol (ß1 , ß2 ), CGP20712A (ß1 ), and SQ22536 (adenylyl cyclase inhibitor), but not by ICI118,551 (ß2 ), SR59230A (ß3 ), ODQ (soluble guanylyl cyclase inhibitor), L-NAME or endothelium removal. In aorta, Adrb1 signalled through cAMP, while ß2 - and ß3 -subtypes through cGMP; isoprenaline relaxation was inhibited by propranolol, ICI118,551, ODQ, L-NAME, and to a lesser extent, by endothelium removal. CL316243 (ß3 -agonist) relaxed aorta, but not MRA. CONCLUSION AND IMPLICATION: Despite all three Adrb subtypes being found in both vessels, Adrb1, located in SMCs and acting through the adenylyl cyclase/cAMP pathway, are primarily responsible for vasodilatation in MRA. However, Adrb-mediated vasodilatation in aorta is driven by endothelial Adrb2 and Adrb3, but also by the Adrb2 present in SMCs, and is coupled to the NO/cGMP pathway. These results could help to understand the different physiological roles played by Adrb signalling in regulating conductance and resistance vessels.

Preclinical activity of LBH589 alone or in combination with chemotherapy in a xenogeneic mouse model of human acute lymphoblastic leukemia.

Histone deacetylases (HDACs) have been identified as therapeutic targets due to their regulatory function in chromatin structure and organization. Here, we analyzed the therapeutic effect of LBH589, a class I-II HDAC inhibitor, in acute lymphoblastic leukemia (ALL). In vitro, LBH589 induced dose-dependent antiproliferative and apoptotic effects, which were associated with increased H3 and H4 histone acetylation. Intravenous administration of LBH589 in immunodeficient BALB/c-RAG2(-/-)γc(-/-) mice in which human-derived T and B-ALL cell lines were injected induced a significant reduction in tumor growth. Using primary ALL cells, a xenograft model of human leukemia in BALB/c-RAG2(-/-)γc(-/-) mice was established, allowing continuous passages of transplanted cells to several mouse generations. Treatment of mice engrafted with T or B-ALL cells with LBH589 induced an in vivo increase in the acetylation of H3 and H4, which was accompanied with prolonged survival of LBH589-treated mice in comparison with those receiving vincristine and dexamethasone. Notably, the therapeutic efficacy of LBH589 was significantly enhanced in combination with vincristine and dexamethasone. Our results show the therapeutic activity of LBH589 in combination with standard chemotherapy in pre-clinical models of ALL and suggest that this combination may be of clinical value in the treatment of patients with ALL.

Chronic stress and impaired glutamate function elicit a depressive-like phenotype and common changes in gene expression in the mouse frontal cortex.

Major depression might originate from both environmental and genetic risk factors. The environmental chronic mild stress (CMS) model mimics some environmental factors contributing to human depression and induces anhedonia and helplessness. Mice heterozygous for the synaptic vesicle protein (SVP) vesicular glutamate transporter 1 (VGLUT1) have been proposed as a genetic model of deficient glutamate function linked to depressive-like behaviour. Here, we aimed to identify, in these two experimental models, gene expression changes in the frontal cortex, common to stress and impaired glutamate function. Both VGLUT1(+/-) and CMS mice showed helpless and anhedonic-like behavior. Microarray studies in VGLUT1(+/-) mice revealed regulation of genes involved in apoptosis, neurogenesis, synaptic transmission, protein metabolic process or learning and memory. In addition, RT-PCR studies confirmed gene expression changes in several glutamate, GABA, dopamine and serotonin neurotransmitter receptors. On the other hand, CMS affected the regulation of 147 transcripts, some of them involved in response to stress and oxidoreductase activity. Interestingly, 52 genes were similarly regulated in both models. Specifically, a dowregulation in genes that promote cell proliferation (Anapc7), cell growth (CsnK1g1), cell survival (Hdac3), and inhibition of apoptosis (Dido1) was observed. Genes linked to cytoskeleton (Hspg2, Invs), psychiatric disorders (Grin1, MapK12) or an antioxidant enzyme (Gpx2) were also downregulated. Moreover, genes that inhibit the MAPK pathways (Dusp14), stimulate oxidative metabolism (Eif4a2) and enhance glutamate transmission (Rab8b) were upregulated. We suggest that these genes could form part of the altered "molecular context" underlying depressive-like behaviour in animal models. The clinical relevance of these findings is discussed.