Molecular neurobiology of loss: a role for basolateral amygdala extracellular matrix.

Psychological loss is a common experience that erodes well-being and negatively impacts quality of life. The molecular underpinnings of loss are poorly understood. Here, we investigate the mechanisms of loss using an environmental enrichment removal (ER) paradigm in male rats. The basolateral amygdala (BLA) was identified as a region of interest, demonstrating differential Fos responsivity to ER and having an established role in stress processing and adaptation. A comprehensive multi-omics investigation of the BLA, spanning multiple cohorts, platforms, and analyses, revealed alterations in microglia and the extracellular matrix (ECM). Follow-up studies indicated that ER decreased microglia size, complexity, and phagocytosis, suggesting reduced immune surveillance. Loss also substantially increased ECM coverage, specifically targeting perineuronal nets surrounding parvalbumin interneurons, suggesting decreased plasticity and increased inhibition within the BLA following loss. Behavioral analyses suggest that these molecular effects are linked to impaired BLA salience evaluation, leading to a mismatch between stimulus and reaction intensity. These loss-like behaviors could be rescued by depleting BLA ECM during the removal period, helping us understand the mechanisms underlying loss and revealing novel molecular targets to ameliorate its impact.

Inhibition of prefrontal cortex parvalbumin interneurons mitigates behavioral and physiological sequelae of chronic stress in male mice.

Chronic stress leads to hypofunction of the medial prefrontal cortex (mPFC), mechanisms of which remain to be determined. Enhanced activation of GABAergic of parvalbumin (PV) expressing interneurons (INs) is thought to play a role in stress-induced prefrontal inhibition. In this study, we tested whether chemogenetic inhibition of mPFC PV INs after chronic stress can rescue chronic stress-related behavioral and physiological phenotypes. Mice underwent 2 weeks of chronic variable stress (CVS) followed by a battery of behavioral tests known to be affected by chronic stress exposure, e.g. an open field (OF), novel object recognition (NOR), tail suspension test (TST), sucrose preference test (SPT), and light dark (LD) box. Inhibitory DREADDs were actuated by 3 mg/kg CNO administered 30 min prior to each behavioral test. CVS caused hyperactivity in the OF, reduced sucrose preference in the SPT (indicative of enhanced anhedonia), and increased anxiety-like behavior in the LD box. Inhibition of PV IN after stress mitigated these effects. In addition, CVS also resulted in reduced thymus weight and body weight loss, which were also mitigated by PV IN inhibition. Our results indicate that chronic stress leads to plastic changes in PV INs that may be mitigated by chemogenetic inhibition. Our findings implicate cortical GABAergic INs as a therapeutic target in stress-related diseases.

Phase 2 study of epigenetic priming with decitabine followed by cytarabine for acute myeloid leukemia in older patients.

Acute myeloid leukemia (AML) in older patients has a poor prognosis, low complete remission (CR) rates, and poor overall survival (OS). Preclinical studies have shown synergistic effects of epigenetic priming with hypomethylating agents followed by cytarabine. Based on these data, we hypothesized that an induction regimen using epigenetic priming with decitabine, followed by cytarabine would be effective and safe in older patients with previously untreated AML. Here, we conducted a phase 2 trial in which older patients with previously untreated AML received an induction regimen consisting of 1 or 2 courses of decitabine 20 mg/m2 intravenously (IV) for 5 days followed by cytarabine 100 mg/m2 continuous IV infusion for 5 days. Forty-four patients (median age 76 years) were enrolled, and CR/CRi was achieved by 26 patients (59% of all patients, 66.7% of evaluable patients). Fourteen of 21 (66.7%) patients with adverse cytogenetics achieved CR including six out of seven evaluable patients with TP53 mutations. The 4- and 8-week mortality rates were 2.3% and 9.1%, respectively, with median OS of 10.7 months. These results suggest epigenetic priming with decitabine followed by cytarabine should be considered as an option for first-line therapy in older patients with AML. This trial was registered at www.clinicaltrials.gov as # NCT01829503.

Hippocampal glucocorticoid receptors modulate status epilepticus severity.

Status epilepticus (SE) is a life-threatening medical emergency with significant morbidity and mortality. SE is associated with a robust and sustained increase in serum glucocorticoids, reaching concentrations sufficient to activate the dense population of glucocorticoid receptors (GRs) expressed among hippocampal excitatory neurons. Glucocorticoid exposure can increase hippocampal neuron excitability; however, whether activation of hippocampal GRs during SE exacerbates seizure severity remains unknown. To test this, a viral strategy was used to delete GRs from a subset of hippocampal excitatory neurons in adult male and female mice, producing hippocampal GR knockdown mice. Two weeks after GR knockdown, mice were challenged with the convulsant drug pilocarpine to induce SE. GR knockdown had opposing effects on early vs late seizure behaviors, with sex influencing responses. For both male and female mice, the onset of mild behavioral seizures was accelerated by GR knockdown. In contrast, GR knockdown delayed the onset of more severe convulsive seizures and death in male mice. Concordantly, GR knockdown also blunted the SE-induced rise in serum corticosterone in male mice. GR knockdown did not alter survival times or serum corticosterone in females. To assess whether loss of GR affected susceptibility to SE-induced cell death, within-animal analyses were conducted comparing local GR knockdown rates to local cell loss. GR knockdown did not affect the degree of localized neuronal loss, suggesting cell-intrinsic GR signaling neither protects nor sensitizes neurons to acute SE-induced death. Overall, the findings reveal that hippocampal GRs exert an anti-convulsant role in both males and females in the early stages of SE, followed by a switch to a pro-convulsive role for males only. Findings reveal an unexpected complexity in the interaction between hippocampal GR activation and the progression of SE.

Differential vulnerability of anterior cingulate cortex cell types to diseases and drugs.

In psychiatric disorders, mismatches between disease states and therapeutic strategies are highly pronounced, largely because of unanswered questions regarding specific vulnerabilities of different cell types and therapeutic responses. Which cellular events (housekeeping or salient) are most affected? Which cell types succumb first to challenges, and which exhibit the strongest response to drugs? Are these events coordinated between cell types? How does disease and drug effect this coordination? To address these questions, we analyzed single-nucleus-RNAseq (sn-RNAseq) data from the human anterior cingulate cortex-a region involved in many psychiatric disorders. Density index, a metric for quantifying similarities and dissimilarities across functional profiles, was employed to identify common or salient functional themes across cell types. Cell-specific signatures were integrated with existing disease and drug-specific signatures to determine cell-type-specific vulnerabilities, druggabilities, and responsiveness. Clustering of functional profiles revealed cell types jointly participating in these events. SST and VIP interneurons were found to be most vulnerable, whereas pyramidal neurons were least. Overall, the disease state is superficial layer-centric, influences cell-specific salient themes, strongly impacts disinhibitory neurons, and influences astrocyte interaction with a subset of deep-layer pyramidal neurons. In absence of disease, drugs profiles largely recapitulate disease profiles, offering a possible explanation for drug side effects. However, in presence of disease, drug activities, are deep layer-centric and involve activating a distinct subset of deep-layer pyramidal neurons to circumvent the disease state's disinhibitory circuit malfunction. These findings demonstrate a novel application of sn-RNAseq data to explain drug and disease action at a systems level.

Similarities and dissimilarities between psychiatric cluster disorders.

The common molecular mechanisms underlying psychiatric disorders are not well understood. Prior attempts to assess the pathological mechanisms responsible for psychiatric disorders have been limited by biased selection of comparable disorders, datasets/cohort availability, and challenges with data normalization. Here, using DisGeNET, a gene-disease associations database, we sought to expand such investigations in terms of number and types of diseases. In a top-down manner, we analyzed an unbiased cluster of 36 psychiatric disorders and comorbid conditions at biological pathway, cell-type, drug-target, and chromosome levels and deployed density index, a novel metric to quantify similarities (close to 1) and dissimilarities (close to 0) between these disorders at each level. At pathway level, we show that cognition and neurotransmission drive the similarity and are involved across all disorders, whereas immune-system and signal-response coupling (cell surface receptors, signal transduction, gene expression, and metabolic process) drives the dissimilarity and are involved with specific disorders. The analysis at the drug-target level supports the involvement of neurotransmission-related changes across these disorders. At cell-type level, dendrite-targeting interneurons, across all layers, are most involved. Finally, by matching the clustering pattern at each level of analysis, we showed that the similarity between the disorders is influenced most at the chromosomal level and to some extent at the cellular level. Together, these findings provide first insights into distinct cellular and molecular pathologies, druggable mechanisms associated with several psychiatric disorders and comorbid conditions and demonstrate that similarities between these disorders originate at the chromosome level and disperse in a bottom-up manner at cellular and pathway levels.

Methylation of NRN1 is a novel synthetic lethal marker of PI3K-Akt-mTOR and ATR inhibitors in esophageal cancer.

Wnt, PI3K-Akt-mTOR, and NF-κB pathways were reported to be involved in DNA damage repair (DDR). DDR-deficient cancers become critically dependent on backup DNA repair pathways. Neuritin 1 (NRN1) is reported to be involved in PI3K-Akt-mTOR, and its role in DDR remains unclear. Methylation-specific PCR, siRNA, flow cytometry, esophageal cancer cell lines, and xenograft mouse models were used to examine the role of NRN1 in esophageal cancer. The expression of NRN1 is frequently repressed by promoter region methylation in human esophageal cancer cells. NRN1 was methylated in 50.4% (510/1012) of primary esophageal cancer samples. NRN1 methylation is associated significantly with age (P < .001), tumor size (P < .01), TNM stage (P < .001), differentiation (P < .001) and alcohol consumption (P < .05). We found that NRN1 methylation is an independent prognostic factor for poor 5-y overall survival (P < .001). NRN1 inhibits colony formation, cell proliferation, migration, and invasion, and induces apoptosis and G1/S arrest in esophageal cancer cells. NRN1 suppresses KYSE150 and KYSE30 cells xenografts growth in nude mice. PI3K signaling is reported to activate ATR signaling by targeting CHK1, the downstream component of ATR. By analyzing the synthetic efficiency of NVP-BEZ235 (PI3K inhibitor) and VE-822 (an ATR inhibitor), we found that the combination of NVP-BEZ235 and VE-822 increased cytotoxicity in NRN1 methylated esophageal cancer cells, as well as KYSE150 cell xenografts. In conclusion, NRN1 suppresses esophageal cancer growth both in vitro and in vivo by inhibiting PI3K-Akt-mTOR signaling. Methylation of NRN1 is a novel synthetic lethal marker for PI3K-Akt-mTOR and ATR inhibitors in human esophageal cancer.

Prefrontal cortex PACAP signaling: organization and role in stress regulation.

Pituitary adenylate cyclase-activating polypeptide (PACAP) is an excitatory neuromodulatory peptide strongly implicated in nervous stress processing. Human polymorphism of the primary PACAP receptor (PAC1) is linked to psychiatric disorders, including posttraumatic stress disorder (PTSD). Prefrontal cortex PACAP signaling is associated with processing of traumatic stress and fear learning, suggesting a potential role in PTSD-related deficits. We used RNAscope to define the cellular location of PACAP and PAC1 in the infralimbic cortex (IL). Subsequent experiments used a pharmacological approach to assess the impact of IL PACAP infusion on behavioral and physiological stress response and fear memory. Adult male Sprague-Dawley rats were bilaterally microinjected with PACAP (1 ug) or vehicle into the IL, 30 minutes prior to forced swim test (FST). Blood was sampled at 15, 30, 60, and 120 minutes for analysis of hypothalamic pituitary adrenal (HPA) axis reactivity. Five days after, animals were tested in a 3-day passive avoidance paradigm with subsequent testing of fear retention two weeks later. We observed that PACAP is highly expressed in putative pyramidal neurons (identified by VGlut1 expression), while PAC1 is enriched in interneurons (identified by GAD). Pretreatment with PACAP increased active coping style in the FST, despite higher levels of ACTH and corticosterone. The treatment was also sufficient to cause an increase in anxiety-like behavior in a dark/light crossover test and enhanced retention of passive avoidance. Our data suggest that IL PACAP plays a role in driving stress responses and in processing of fear memories, likely mediated by inhibition of cortical drive.

Brain mechanisms of HPA axis regulation: neurocircuitry and feedback in context Richard Kvetnansky lecture.

Regulation of stress reactivity is a fundamental priority of all organisms. Stress responses are critical for survival, yet can also cause physical and psychological damage. This review provides a synopsis of brain mechanisms designed to control physiological responses to stress, focusing primarily on glucocorticoid secretion via the hypothalamo-pituitary-adrenocortical (HPA) axis. The literature provides strong support for multi-faceted control of HPA axis responses, involving both direct and indirect actions at paraventricular nucleus (PVN) corticotropin releasing hormone neurons driving the secretory cascade. The PVN is directly excited by afferents from brainstem and hypothalamic circuits, likely relaying information on homeostatic challenge. Amygdala subnuclei drive HPA axis responses indirectly via disinhibition, mediated by GABAergic relays onto PVN-projecting neurons in the hypothalamus and bed nucleus of the stria terminalis (BST). Inhibition of stressor-evoked HPA axis responses is mediated by an elaborate network of glucocorticoid receptor (GR)-containing circuits, providing a distributed negative feedback signal that inhibits PVN neurons. Prefrontal and hippocampal neurons play a major role in HPA axis inhibition, again mediated by hypothalamic and BST GABAergic relays to the PVN. The complexity of the regulatory process suggests that information on stressors is integrated across functional disparate brain circuits prior to accessing the PVN, with regions such as the BST in prime position to relay contextual information provided by these sources into appropriate HPA activation. Dysregulation of the HPA in disease is likely a product of inappropriate checks and balances between excitatory and inhibitory inputs ultimately impacting PVN output.

Caveolin-1 promotes the tumor suppressor properties of oncogene-induced cellular senescence.

Oncogene-induced senescence (OIS) is considered a powerful tumor suppressor mechanism. Caveolin-1 acts as a scaffolding protein to functionally regulate signaling molecules. We demonstrate that a lack of caveolin-1 expression inhibits oncogenic K-Ras (K-RasG12V)-induced premature senescence in mouse embryonic fibroblasts and normal human bronchial epithelial cells. Oncogenic K-Ras induces senescence by limiting the detoxification function of MTH1. We found that K-RasG12V promotes the interaction of caveolin-1 with MTH1, which results in inhibition of MTH1 activity. Lung cancer cells expressing oncogenic K-Ras have bypassed the senescence barrier. Interestingly, overexpression of caveolin-1 restores cellular senescence in both A549 and H460 lung cancer cells and inhibits their transformed phenotype. In support of these findings, our in vivo data demonstrate that overexpression of oncogenic K-Ras (K-RasG12D) induces cellular senescence in the lung of wildtype but not caveolin-1-null mice. A lack of K-RasG12D-induced premature senescence in caveolin-1-null mice results in the formation of more abundant lung tumors. Consistent with these data, caveolin-1-null mice overexpressing K-RasG12D display accelerated mortality. Finally, our animal data were supported by human sample analysis in which we show that caveolin-1 expression is dramatically down-regulated in lung adenocarcinomas from lung cancer patients, both at the mRNA and protein levels, and that low caveolin-1 expression is associated with poor survival. Together, our data suggest that lung cancer cells escape oncogene-induced premature senescence through down-regulation of caveolin-1 expression to progress from premalignant lesions to cancer.

Fat-brain connections: Adipocyte glucocorticoid control of stress and metabolism.

Glucocorticoids act via multiple mechanisms to mobilize energy for maintenance and restoration of homeostasis. In adipose tissue, glucocorticoids can promote lipolysis and facilitate adipocyte differentiation/growth, serving both energy-mobilizing and restorative processes during negative energy balance. Recent data suggest that adipose-dependent feedback may also be involved in regulation of stress responses. Adipocyte glucocorticoid receptor (GR) deletion causes increased HPA axis stress reactivity, due to a loss of negative feedback signals into the CNS. The fat-to-brain signal may be mediated by neuronal mechanisms, release of adipokines or increased lipolysis. The ability of adipose GRs to inhibit psychogenic as well as metabolic stress responses suggests that (1) feedback regulation of the HPA axis occurs across multiple bodily compartments, and (2) fat tissue integrates psychogenic stress signals. These studies support a link between stress biology and energy metabolism, a connection that has clear relevance for numerous disease states and their comorbidities.

Feasibility of lung cancer prediction from low-dose CT scan and smoking factors using causal models.

INTRODUCTION: Low-dose CT (LDCT) is currently used in lung cancer screening of high-risk populations for early lung cancer diagnosis. However, 96% of individuals with detected nodules are false positives. METHODS: In order to develop an efficient early lung cancer predictor from clinical, demographic and LDCT features, we studied a total of 218 subjects with lung cancer or benign nodules. Probabilistic graphical models (PGMs) were used to integrate demographics, clinical data and LDCT features from 92 subjects (training cohort) from the Pittsburgh Lung Screening Study cohort. RESULTS: Learnt PGMs identified three variables directly (causally) linked to malignant nodules and the largest benign nodule and used them to build the Lung Cancer Causal Model (LCCM), which was validated in a separate cohort of 126 subjects. Nodule and vessel numbers and years since the subject quit smoking were sufficient to discriminate malignant from benign nodules. Comparison with existing predictors in the training and validation cohorts showed that (1) incorporating LDCT scan features greatly enhances predictive accuracy; and (2) LCCM improves cancer detection over existing methods, including the Brock parsimonious model (p<0.001). Notably, the number of surrounding vessels, a feature not previously used in predictive models, significantly improves predictive efficiency. Based on the validation cohort results, LCCM is able to identify 30% of the benign nodules without risk of misclassifying cancer nodules. DISCUSSION: LCCM shows promise as a lung cancer predictor as it is significantly improved over existing models. Validated in a larger, prospective study, it may help reduce unnecessary follow-up visits and procedures.

Disruption of Glucagon-Like Peptide 1 Signaling in Sim1 Neurons Reduces Physiological and Behavioral Reactivity to Acute and Chronic Stress.

Organismal stress initiates a tightly orchestrated set of responses involving complex physiological and neurocognitive systems. Here, we present evidence for glucagon-like peptide 1 (GLP-1)-mediated paraventricular hypothalamic circuit coordinating the global stress response. The GLP-1 receptor (Glp1r) in mice was knocked down in neurons expressing single-minded 1, a transcription factor abundantly expressed in the paraventricular nucleus (PVN) of the hypothalamus. Mice with single-minded 1-mediated Glp1r knockdown had reduced hypothalamic-pituitary-adrenal axis responses to both acute and chronic stress and were protected against weight loss associated with chronic stress. In addition, regional Glp1r knockdown attenuated stress-induced cardiovascular responses accompanied by decreased sympathetic drive to the heart. Finally, Glp1r knockdown reduced anxiety-like behavior, implicating PVN GLP-1 signaling in behavioral stress reactivity. Collectively, these findings support a circuit whereby brainstem GLP-1 activates PVN signaling to mount an appropriate whole-organism response to stress. These results raise the possibility that dysfunction of this system may contribute to stress-related pathologies, and thereby provide a novel target for intervention. SIGNIFICANCE STATEMENT: Dysfunctional stress responses are linked to a number of somatic and psychiatric diseases, emphasizing the importance of precise neuronal control of effector pathways. Pharmacological evidence suggests a role for glucagon-like peptide-1 (GLP-1) in modulating stress responses. Using a targeted knockdown of the GLP-1 receptor in the single-minded 1 neurons, we show dependence of paraventricular nucleus GLP-1 signaling in the coordination of neuroendocrine, autonomic, and behavioral responses to acute and chronic stress. To our knowledge, this is the first direct demonstration of an obligate brainstem-to-hypothalamus circuit orchestrating general stress excitation across multiple effector systems. These findings provide novel information regarding signaling pathways coordinating central control of whole-body stress reactivity.

Regulation of Hypothalamo-Pituitary-Adrenocortical Responses to Stressors by the Nucleus of the Solitary Tract/Dorsal Vagal Complex.

Hindbrain neurons in the nucleus of the solitary tract (NTS) are critical for regulation of hypothalamo-pituitary-adrenocortical (HPA) responses to stress. It is well known that noradrenergic (as well as adrenergic) neurons in the NTS send direct projections to hypophysiotropic corticotropin-releasing hormone (CRH) neurons and control activation of HPA axis responses to acute systemic (but not psychogenic) stressors. Norepinephrine (NE) signaling via alpha1 receptors is primarily excitatory, working either directly on CRH neurons or through presynaptic activation of glutamate release. However, there is also evidence for NE inhibition of CRH neurons (possibly via beta receptors), an effect that may occur at higher levels of stimulation, suggesting that NE effects on the HPA axis may be context-dependent. Lesions of ascending NE inputs to the paraventricular nucleus attenuate stress-induced ACTH but not corticosterone release after chronic stress, indicating reduction in central HPA drive and increased adrenal sensitivity. Non-catecholaminergic NTS glucagon-like peptide 1/glutamate neurons play a broader role in stress regulation, being important in HPA activation to both systemic and psychogenic stressors as well as HPA axis sensitization under conditions of chronic stress. Overall, the data highlight the importance of the NTS as a key regulatory node for coordination of acute and chronic stress.

Adolescent environmental enrichment prevents behavioral and physiological sequelae of adolescent chronic stress in female (but not male) rats.

The late adolescent period is characterized by marked neurodevelopmental and endocrine fluctuations in the transition to early adulthood. Adolescents are highly responsive to the external environment, which enhances their ability to adapt and recover from challenges when given nurturing influences, but also makes them vulnerable to aberrant development when exposed to prolonged adverse situations. Female rats are particularly sensitive to the effects of chronic stress in adolescence, which manifests as passive coping strategies and blunted hypothalamo-pituitary adrenocortical (HPA) stress responses in adulthood. We sought to intervene by exposing adolescent rats to environmental enrichment (EE) immediately prior to and during chronic stress, hypothesizing that EE would minimize or prevent the long-term effects of stress that emerge in adult females. To test this, we exposed male and female rats to EE on postnatal days (PND) 33-60 and implemented chronic variable stress (CVS) on PND 40-60. CVS consisted of twice-daily unpredictable stressors. Experimental groups included: CVS/unenriched, unstressed/EE, CVS/EE and unstressed/unenriched (n = 10 of each sex/group). In adulthood, we measured behavior in the open field test and forced swim test (FST) and collected blood samples following the FST. We found that environmental enrichment given during the adolescent period prevented the chronic stress-induced transition to passive coping in the FST and reversed decreases in peak adrenocortical responsiveness observed in adult females. Adolescent enrichment had little to no effect on males or unstressed females tested in adulthood, indicating that beneficial effects are specific to females that were exposed to chronic stress.

DREAMing: a simple and ultrasensitive method for assessing intratumor epigenetic heterogeneity directly from liquid biopsies.

Many cancers comprise heterogeneous populations of cells at primary and metastatic sites throughout the body. The presence or emergence of distinct subclones with drug-resistant genetic and epigenetic phenotypes within these populations can greatly complicate therapeutic intervention. Liquid biopsies of peripheral blood from cancer patients have been suggested as an ideal means of sampling intratumor genetic and epigenetic heterogeneity for diagnostics, monitoring and therapeutic guidance. However, current molecular diagnostic and sequencing methods are not well suited to the routine assessment of epigenetic heterogeneity in difficult samples such as liquid biopsies that contain intrinsically low fractional concentrations of circulating tumor DNA (ctDNA) and rare epigenetic subclonal populations. Here we report an alternative approach, deemed DREAMing (Discrimination of Rare EpiAlleles by Melt), which uses semi-limiting dilution and precise melt curve analysis to distinguish and enumerate individual copies of epiallelic species at single-CpG-site resolution in fractions as low as 0.005%, providing facile and inexpensive ultrasensitive assessment of locus-specific epigenetic heterogeneity directly from liquid biopsies. The technique is demonstrated here for the evaluation of epigenetic heterogeneity at p14(ARF) and BRCA1 gene-promoter loci in liquid biopsies obtained from patients in association with non-small cell lung cancer (NSCLC) and myelodysplastic/myeloproliferative neoplasms (MDS/MPN), respectively.

Evaluation of performance and perceptions of electronic vs. paper multiple-choice exams.

In the veterinary professional curriculum, methods of examination in many courses are transitioning from the traditional paper-based exams to electronic-based exams. Therefore, a controlled trial to evaluate the impact of testing methodology on examination performance in a veterinary physiology course was designed and implemented. Formalized surveys and focus group discussions were also used to determine student attitudes toward the examination formats. In total, 134 first-year veterinary students and 11 PhD/MS students were administered a total of 4 exams throughout 1 semester (2 on paper and 2 electronically) using a split-halves design. The paper (P) and electronic (E) exams contained 25 identical multiple-choice questions. Students were randomly assigned to two groups and were given exams in one of two sequences (E-P-E-P or P-E-P-E). Participants consented to and completed two anonymous surveys vis à vis their experience. Out of a maximum raw score of 25, the mean score for electronic examinations (20.8; 95% confidence interval, 20.3-21.2) was significantly (P = 0.01) greater than that for paper examinations (20.3; 95% confidence interval, 20.0-20.7). However, students expressed numerous concerns with the electronic examination format, and, at the completion of the study, 87% preferred to take their examination on paper rather than the electronic format. These data show that student attitudes concerning the examination format are not primarily determined by examination results, and that the additional anxiety related to the electronic examination format plays a large role in student attitudes.

Azacitidine with or without Entinostat for the treatment of therapy-related myeloid neoplasm: further results of the E1905 North American Leukemia Intergroup study.

Therapy-related myeloid neoplasms (tMN) are serious late effects of the treatment of cancer with poor response to conventional treatment. Azacitidine (AZA) has been used to treat patients with tMN but current data are retrospective. We present here 47 tMN patients prospectively enrolled as a specific cohort in the E1905 study. TheE1905 study was a randomized phase 2 study (NCT00313586) testing 10 d of AZA (50 mg/m(2) /d) +/- the histone deacetylase inhibitor entinostat (4 mg/m(2) /d PO day-3 and day-10). A total of 47 patients [29 therapy-related myelosyspastic syndrome (t-MDS) and 18 therapy-related acute myeloid leukaemia (t-AML)] were recruited to the study. 24 patients were treated with AZA monotherapy and 23 with AZA+entinostat. The median number of administered cycles was 4, significantly higher in patients treated with AZA (6 cycles vs. 3 cycles, P = 0·008). Haematological normalization rates were 46% in monotherapy and 17% in the combination arm. Median overall survivals were 13 and 6 months, respectively. The novel 50 * 10 schedule of azacitidine appears effective, with response rates, when given as single agent, comparable to those for patients with de novo MDS/AML treated on the same protocol. However, the combination of AZA and entinostat was associated with increased toxicity and could not be recommended for treatment of tMN.

On Predicting lung cancer subtypes using 'omic' data from tumor and tumor-adjacent histologically-normal tissue.

BACKGROUND: Adenocarcinoma (ADC) and squamous cell carcinoma (SCC) are the most prevalent histological types among lung cancers. Distinguishing between these subtypes is critically important because they have different implications for prognosis and treatment. Normally, histopathological analyses are used to distinguish between the two, where the tissue samples are collected based on small endoscopic samples or needle aspirations. However, the lack of cell architecture in these small tissue samples hampers the process of distinguishing between the two subtypes. Molecular profiling can also be used to discriminate between the two lung cancer subtypes, on condition that the biopsy is composed of at least 50 % of tumor cells. However, for some cases, the tissue composition of a biopsy might be a mix of tumor and tumor-adjacent histologically normal tissue (TAHN). When this happens, a new biopsy is required, with associated cost, risks and discomfort to the patient. To avoid this problem, we hypothesize that a computational method can distinguish between lung cancer subtypes given tumor and TAHN tissue. METHODS: Using publicly available datasets for gene expression and DNA methylation, we applied four classification tasks, depending on the possible combinations of tumor and TAHN tissue. First, we used a feature selector (ReliefF/Limma) to select relevant variables, which were then used to build a simple naïve Bayes classification model. Then, we evaluated the classification performance of our models by measuring the area under the receiver operating characteristic curve (AUC). Finally, we analyzed the relevance of the selected genes using hierarchical clustering and IPA® software for gene functional analysis. RESULTS: All Bayesian models achieved high classification performance (AUC > 0.94), which were confirmed by hierarchical cluster analysis. From the genes selected, 25 (93 %) were found to be related to cancer (19 were associated with ADC or SCC), confirming the biological relevance of our method. CONCLUSIONS: The results from this study confirm that computational methods using tumor and TAHN tissue can serve as a prognostic tool for lung cancer subtype classification. Our study complements results from other studies where TAHN tissue has been used as prognostic tool for prostate cancer. The clinical implications of this finding could greatly benefit lung cancer patients.

Divergent effects of repeated restraint versus chronic variable stress on prefrontal cortical immune status after LPS injection.

Previous work from our group has shown that chronic homotypic stress (repeated restraint - RR) increases microglial morphological activation in the prefrontal cortex (PFC), while chronic heterotypic stress (chronic variable stress - CVS) produces no such effect. Therefore, we hypothesized that stressor modality would also determine the susceptibility of the PFC to a subsequent inflammatory stimulus (low dose lipopolysaccharide (LPS)). We found that RR, but not CVS, increased Iba-1 soma size in the PFC after LPS injection, consistent with microglial activation. In contrast, CVS decreased gene expression of proinflammatory cytokines and Iba-1 in the PFC under baseline conditions, which were not further affected by LPS. Thus, RR appears to promote microglial responses to LPS, whereas CVS is largely immunosuppressive. The results suggest that neuroimmune changes caused by CVS may to some extent protect the PFC from subsequent inflammatory stimuli. These data suggest that modality and/or intensity of stressful experiences will be a major determinant of central inflammation and its effect on prefrontal cortex-mediated functions.