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DNA Damage Repair Interference By WEE1 Inhibition with AZD1775 Overcomes Combined Azacitidine and Venetoclax Resistance in Acute Myeloid Leukmeia (AML) [Meeting Abstract]

Tibes, R; Ferreira, Coutinho D; Tuen, M T; Chen, X; Glytsou, C; Aifantis, I; Shmelkov, S
Acute myeloid leukemia (AML) has remained one of the most treatment resistant and deadliest cancers. The survival of AML blast cells is controlled by the balance of anti- and pro-apoptotic proteins. Recently approved Bcl-2 targeted therapy of AML with the Bcl-2 specific inhibitor Venetoclax in combinations has improved patients outcomes. However, a priori and developing resistance to venetoclax combinations with hypomethylating agents (HMA) azacitidine and decitabine challenge this treatment. As such, novel therapies to overcome venetoclax-HMA resistance are urgently needed. We have identified a combination of DNA damage repair interference by WEE1 inhibition with AZD1775, combined with low dose cytarabine (AraC) as an effective strategy to overcome combined venetoclax-azacitidine resistance (VAR). AZD1775 with low dose AraC induced massive apoptosis (by Annexin V and cleaved caspase-3) and almost completely reduced viability and clonogenic growth of primary AML cells. To delineate the molecular mechanism of the synergistic effect of AZD1775/AraC we performed RNAseq analysis of single agent or the combination of AZD1775+AraC in AML cell lines and primary CD34+ selected AML patient cells with the goal to identify deferentially regulated genes indicating a mechanistic underpinning of the potent activity. Only 2 genes were deferentially regulated across cell lines and CD34+ selected cells under AZD1775+AraC treatment: one of these is NR4A1, an orphan nuclear receptor, which we went on to validate as a potential downstream target of Wee1 inhibition. The inactivation of NR4A1 in mice was previously shown to induce AML and to maintain leukemia stem cells. Using qPCR we confirmed that the expression of NR4A1 is upregulated after AZD1775/AraC combo treatment in human leukemic cells. We then demonstrated that activators of NR4A1 (cytosporone B and pPhOCH3) reduce viability of leukemic cells, while NR4A1 inhibitor pPhOH was able to abolish the effect of AZD1775/AraC combo treatment increasing leukemic cell viability]. To investigate the involvement of mitochondria in the effect of AZD1775/AraC treatment we performed the expression of mitochondrial genes and pathway analyses in RNAseq data and found that mitochondrial gene expression, including many genes involved in apoptosis, has most dramatic changes in the combo treatment if compared to the single agents. Subsequently, we have examined the expression of the main BCL-2 family apoptotic genes by qPCR and western blot analysis. We found that AZD1775/AraC induces the expression of Bim isoforms, whereas Bcl-2, Mcl-1 and Bcl-Xl were largely unaffected. NR4A1 was previously shown to translocate to mitochondria, release Bim from Bcl-2 protein binding, as well as convert Bcl-2 to an extreme potent pro-apoptotic form. Finally, we generated several additional VAR cell lines and cells with subclones and demonstrated that AZD1775/AraC combination treatment is able to overcome VAR in almost every clone. Our results show that DNA damage repair interference with Wee1 inhibition has the potential to overcome VAR through a novel mechanisms of AZD1775 increasing NR4A1, freeing pro-apoptotic Bim irrespective of anti-apoptotic Bcl-2 proteins leading to massive apoptotic cell death in AML cells. The precise molecular mechanisms and the involvement of NR4A1 in this phenomenon will be presented at the meeting. Our findings will help to develop new therapeutic strategies in AML treatment and a trial of AZD1775 + AraC in AML is currently ongoing. Disclosures: No relevant conflicts of interest to declare.XXCopyright
EMBASE:2013253632
ISSN: 0006-4971
CID: 4928192

Combinatorial Targeting of Distributed Forebrain Networks Reverses Noise Hypersensitivity in a Model of Autism Spectrum Disorder

Nakajima, Miho; Schmitt, L Ian; Feng, Guoping; Halassa, Michael M
Autism spectrum disorder (ASD) is associated with noise hypersensitivity, the suboptimal extraction of meaningful signals in noisy environments. Because sensory filtering can involve distinct automatic and executive circuit mechanisms, however, developing circuit-specific therapeutic strategies for ASD noise hypersensitivity can be challenging. Here, we find that both of these processes are individually perturbed in one monogenic form of ASD, Ptchd1 deletion. Although Ptchd1 is preferentially expressed in the thalamic reticular nucleus during development, pharmacological rescue of thalamic perturbations in knockout (KO) mice only normalized automatic sensory filtering. By discovering a separate prefrontal perturbation in these animals and adopting a combinatorial pharmacological approach that also rescued its associated goal-directed noise filtering deficit, we achieved full normalization of noise hypersensitivity in this model. Overall, our work highlights the importance of identifying large-scale functional circuit architectures and utilizing them as access points for behavioral disease correction.
PMID: 31648899
ISSN: 1097-4199
CID: 4161762

During infant maltreatment, stress targets hippocampus, but stress with mother present targets amygdala and social behavior

Raineki, Charlis; Opendak, Maya; Sarro, Emma; Showler, Ashleigh; Bui, Kevin; McEwen, Bruce S; Wilson, Donald A; Sullivan, Regina M
Infant maltreatment increases vulnerability to physical and mental disorders, yet specific mechanisms embedded within this complex infant experience that induce this vulnerability remain elusive. To define critical features of maltreatment-induced vulnerability, rat pups were reared from postnatal day 8 (PN8) with a maltreating mother, which produced amygdala and hippocampal deficits and decreased social behavior at PN13. Next, we deconstructed the maltreatment experience to reveal sufficient and necessary conditions to induce this phenotype. Social behavior and amygdala deficits (volume, neurogenesis, c-Fos, local field potential) required combined chronic high corticosterone and maternal presence (not maternal behavior). Hippocampal deficits were induced by chronic high corticosterone regardless of social context. Causation was shown by blocking corticosterone during maltreatment and suppressing amygdala activity during social behavior testing. These results highlight (1) that early life maltreatment initiates multiple pathways to pathology, each with distinct causal mechanisms and outcomes, and (2) the importance of social presence on brain development.
PMID: 31636210
ISSN: 1091-6490
CID: 4175632

A Critical Review of Qualitative Interview Studies with Alcoholics Anonymous Members

Glassman, Hannah S; Rhodes, Paul; Buus, Niels
Background: Alcoholics Anonymous (AA) is a community-based NGO that supports people with alcohol misuse concerns to achieve and maintain abstinence. Qualitative methods are best suited to investigate individual experiences of recovery in AA, since this typically involves not only abstinence from alcohol but also the global psychological growth of the whole person. Despite this, the growing body of qualitative research exploring individual experiences in AA has yet to be collated. Objectives: The aims of this paper were to systematically search for and critically review qualitative interview studies with AA members. Methods: A systematic database and citation search identified 21 articles published between 1977 and 2014. Two independent reviewers assessed each research report and extracted data pertaining to the findings and the methodological quality of the studies. Results: Major themes across the reviewed articles included 'rock-bottom' experiences and powerlessness, and identity and change processes in AA. Findings related to the methodological quality of the papers were both general to qualitative research and more specific to AA. Conclusions/Importance: Research in this field has been characterized by a relatively uncritical discovery of AA narratives among AA members and by a lack of methodological rigor, which is likely to perpetuate its negative standing in the context of academia, and therefore in public and political discourse. Overall, findings demonstrated a pressing need for high quality qualitative research on AA.
PMID: 31686562
ISSN: 1532-2491
CID: 4175752

Interictal epileptiform discharges shape large-scale intercortical communication

Dahal, Prawesh; Ghani, Naureen; Flinker, Adeen; Dugan, Patricia; Friedman, Daniel; Doyle, Werner; Devinsky, Orrin; Khodagholy, Dion; Gelinas, Jennifer N
Dynamic interactions between remote but functionally specialized brain regions enable complex information processing. This intercortical communication is disrupted in the neural networks of patients with focal epilepsy, and epileptic activity can exert widespread effects within the brain. Using large-scale human intracranial electroencephalography recordings, we show that interictal epileptiform discharges (IEDs) are significantly coupled with spindles in discrete, individualized brain regions outside of the epileptic network. We found that a substantial proportion of these localized spindles travel across the cortical surface. Brain regions that participate in this IED-driven oscillatory coupling express spindles that have a broader spatial extent and higher tendency to propagate than spindles occurring in uncoupled regions. These altered spatiotemporal oscillatory properties identify areas that are shaped by epileptic activity independent of IED or seizure detection. Our findings suggest that IED-spindle coupling may be an important mechanism of interictal global network dysfunction that could be targeted to prevent disruption of normal neural activity.
PMID: 31501850
ISSN: 1460-2156
CID: 4087702

Trends in the Prevalence and Incidence of Attention-Deficit/Hyperactivity Disorder Among Adults and Children of Different Racial and Ethnic Groups

Chung, Winston; Jiang, Sheng-Fang; Paksarian, Diana; Nikolaidis, Aki; Castellanos, F Xavier; Merikangas, Kathleen R; Milham, Michael P
Importance/UNASSIGNED:An increasing prevalence of adult attention-deficit/hyperactivity disorder (ADHD) diagnosis and treatment has been reported in clinical settings and administrative data in the United States. However, there are limited data on recent trends of adult ADHD diagnosis among racial/ethnic subgroups. Objective/UNASSIGNED:To examine trends, including associated demographic characteristics, psychiatric diagnoses, and negative outcomes, in the prevalence and incidence of adult ADHD diagnosis among 7 racial/ethnic groups during a 10-year period. Design, Setting, and Participants/UNASSIGNED:This cohort study investigated trends in the diagnosis of ADHD in adults who identified as African American or black, Native American, Pacific Islander, Latino or Hispanic, non-Hispanic white, Asian American, or other using the Kaiser Permanente Northern California health plan medical records. A total of 5 282 877 adult patients and 867 453 children aged 5 to 11 years who received care at Kaiser Permanente Northern California from January 1, 2007, to December 31, 2016, were included. Data analysis was performed from January 2017 through September 2019. Exposures/UNASSIGNED:Period of ADHD diagnosis. Main Outcomes and Measures/UNASSIGNED:Prevalence and incidence of licensed mental health clinician-diagnosed ADHD in adults and prevalence of licensed mental health clinician-diagnosed ADHD in children aged 5 to 11 years. Results/UNASSIGNED:Of 5 282 877 adult patients (1 155 790 [21.9%] aged 25-34 years; 2 667 562 [50.5%] women; 2 204 493 [41.7%] white individuals), 59 371 (1.12%) received diagnoses of ADHD. Prevalence increased from 0.43% in 2007 to 0.96% in 2016. Among 867 453 children aged 5 to 11 years (424 449 [48.9%] girls; 260 236 [30.0%] white individuals), prevalence increased from 2.96% in 2007 to 3.74% in 2016. During the study period, annual adult ADHD prevalence increased for every race/ethnicity, but white individuals consistently had the highest prevalence rates (white individuals: 0.67%-1.42%; black individuals: 0.22%-0.69%; Native American individuals: 0.56%-1.14%; Pacific Islander individuals: 0.11%-0.39%; Hispanic or Latino individuals: 0.25%-0.65%; Asian American individuals: 0.11%-0.35%; individuals from other races/ethnicities: 0.29%-0.71%). Incidence of ADHD diagnosis per 10 000 person-years increased from 9.43 in 2007 to 13.49 in 2016. Younger age (eg, >65 years vs 18-24 years: odds ratio [OR], 0.094; 95% CI, 0.088-0.101; P < .001), male sex (women: OR, 0.943; 95% CI, 0.928-0.959; P < .001), white race (eg, Asian patients vs white patients: OR, 0.248; 95% CI, 0.240-0.257; P < .001), being divorced (OR, 1.131; 95% CI, 1.093-1.171; P < .001), being employed (eg, retired vs employed persons: OR, 0.278; 95% CI, 0.267-0.290; P < .001), and having a higher median education level (OR, 2.156; 95% CI, 2.062-2.256; P < .001) were positively associated with odds of ADHD diagnosis. Having an eating disorder (OR, 5.192; 95% CI, 4.926-5.473; P < .001), depressive disorder (OR, 4.118; 95% CI, 4.030-4.207; P < .001), bipolar disorder (OR, 4.722; 95% CI, 4.556-4.894; P < .001), or anxiety disorder (OR, 2.438; 95% CI, 2.385-2.491; P < .001) was associated with higher odds of receiving an ADHD diagnosis. Adults with ADHD had significantly higher odds of frequent health care utilization (OR, 1.303; 95% CI, 1.272-1.334; P < .001) and sexually transmitted infections (OR, 1.289; 95% CI 1.251-1.329; P < .001) compared with adults with no ADHD diagnosis. Conclusions and Relevance/UNASSIGNED:This study confirmed the reported increases in rates of ADHD diagnosis among adults, showing substantially lower rates of detection among minority racial/ethnic subgroups in the United States. Higher odds of negative outcomes reflect the economic and personal consequences that substantiate the need to improve assessment and treatment of ADHD in adults.
PMID: 31675080
ISSN: 2574-3805
CID: 4163452

Stepwise functional connectivity reveals altered sensory-multimodal integration in medication-naive adults with attention deficit hyperactivity disorder

Pretus, Clara; Marcos-Vidal, Luis; Martinez-Garcia, Magdalena; Picado, Marisol; Ramos-Quiroga, Josep Antoni; Richarte, Vanesa; Castellanos, Francisco X; Sepulcre, Jorge; Desco, Manuel; Vilarroya, Ascar; Carmona, Susanna
Neuroimaging studies indicate that children with attention-deficit/hyperactivity disorder (ADHD) present alterations in several functional networks of the sensation-to-cognition spectrum. These alterations include functional overconnectivity within sensory regions and underconnectivity between sensory regions and neural hubs supporting higher order cognitive functions. Today, it is unknown whether this same pattern of alterations persists in adult patients with ADHD who had never been medicated for their condition. The aim of the present study was to assess whether medication-naïve adults with ADHD presented alterations in functional networks of the sensation-to-cognition spectrum. Thirty-one medication-naïve adults with ADHD and twenty-two healthy adults underwent resting-state functional magnetic resonance imaging (rs-fMRI). Stepwise functional connectivity (SFC) was used to characterize the pattern of functional connectivity between sensory seed regions and the rest of the brain at direct, short, intermediate, and long functional connectivity distances, thus covering the continuum from the sensory input to the neural hubs supporting higher order cognitive functions. As compared to controls, adults with ADHD presented increased SFC degree within primary sensory regions and decreased SFC degree between sensory seeds and higher order integration nodes. In addition, they exhibited decreased connectivity degree between sensory seeds and regions of the default-mode network. Consistently, the higher the score in clinical severity scales the lower connectivity degree between seed regions and the default mode network.
PMID: 31322305
ISSN: 1097-0193
CID: 3979882

Responses of neurons in macaque MT to unikinetic plaids

Wallisch, Pascal; Movshon, J Anthony
Response properties of MT neurons are often studied with "bikinetic" plaid stimuli, which consist of two superimposed sine wave gratings moving in different directions. Oculomotor studies using "unikinetic plaids" in which only one of the two superimposed gratings moves suggest that the eyes first move reflexively in the direction of the moving grating and only later converge on the perceived direction of the moving pattern. MT has been implicated as the source of visual signals that drives these responses. We wanted to know whether stationary gratings, which have little effect on MT cells when presented alone, would influence MT responses when paired with a moving grating. We recorded extracellularly from neurons in area MT and measured responses to stationary and moving gratings, and to their sums: bikinetic and unikinetic plaids. As expected, stationary gratings presented alone had a very modest influence on the activity of MT neurons. Responses to moving gratings and bikinetic plaids were similar to those previously reported and revealed cells selective for the motion of plaid patterns and of their components (pattern and component cells). When these neurons were probed with unikinetic plaids, pattern cells shifted their direction preferences in a way that revealed the influence of the static grating. Component cell preferences shifted little or not at all. These results support the notion that pattern-selective neurons in area MT integrate component motions that differ widely in speed, and that they do so in a way that is consistent with an intersection-of-constraints model.NEW & NOTEWORTHY Human perceptual and eye movement responses to moving gratings are influenced by adding a second, static grating to create a "unikinetic" plaid. Cells in MT do not respond to static gratings, but those gratings still influence the direction selectivity of some MT cells. The cells influenced by static gratings are those tuned for the motion of global patterns, but not those tuned only for the individual components of moving targets.
PMCID:6879962
PMID: 31509468
ISSN: 1522-1598
CID: 4228302

Top-down cortical control of acute and chronic pain

Urien, Louise; Wang, Jing
Acute pain has an evolutionary role for the detection of and response to physical harm. In some cases, however, acute pain can impair function and lead to other morbidities. Chronic pain, meanwhile, can present as a psychopathological condition that significantly interferes with daily living. Most basic and translational pain research has focused on the molecular and cellular mechanisms in the spinal and peripheral nervous systems. In contrast, the brain plays a key role in the affective manifestation and cognitive control of pain. In particular, several cortical regions, such as the somatosensory cortex, prefrontal cortex, insular, and anterior cingulate cortex, are well-known to be activated by acute pain signals, and neurons in these regions have been demonstrated to undergo changes in response to chronic pain. Furthermore, these cortical regions can project to a number of forebrain and limbic structures to exert powerful top-down control of not only sensory pain transmission but also affective pain expression, and such cortical regulatory mechanisms are particularly relevant in chronic pain states. Newer techniques have emerged that allow detailed studies of central pain circuits in animal models, as well as how such circuits are modified by the presence of chronic pain and other predisposing psychosomatic factors. These mechanistic approaches can complement imaging in human studies. At the therapeutic level, a number of pharmacological and non-pharmacological interventions have recently been shown to engage these top-down control systems to provide analgesia. In this review, we will discuss how pain signals reach important cortical regions, and how these regions in turn project to sub-cortical areas of the brain to exert profound modulation of the pain experience. In addition, we will discuss the clinical relevance of such top-down pain regulation mechanisms.
PMID: 31609921
ISSN: 1534-7796
CID: 4140252

Recurrent functional misinterpretation of RNA-seq data caused by sample-specific gene length bias

Mandelboum, Shir; Manber, Zohar; Elroy-Stein, Orna; Elkon, Ran
Data normalization is a critical step in RNA sequencing (RNA-seq) analysis, aiming to remove systematic effects from the data to ensure that technical biases have minimal impact on the results. Analyzing numerous RNA-seq datasets, we detected a prevalent sample-specific length effect that leads to a strong association between gene length and fold-change estimates between samples. This stochastic sample-specific effect is not corrected by common normalization methods, including reads per kilobase of transcript length per million reads (RPKM), Trimmed Mean of M values (TMM), relative log expression (RLE), and quantile and upper-quartile normalization. Importantly, we demonstrate that this bias causes recurrent false positive calls by gene-set enrichment analysis (GSEA) methods, thereby leading to frequent functional misinterpretation of the data. Gene sets characterized by markedly short genes (e.g., ribosomal protein genes) or long genes (e.g., extracellular matrix genes) are particularly prone to such false calls. This sample-specific length bias is effectively removed by the conditional quantile normalization (cqn) and EDASeq methods, which allow the integration of gene length as a sample-specific covariate. Consequently, using these normalization methods led to substantial reduction in GSEA false results while retaining true ones. In addition, we found that application of gene-set tests that take into account gene-gene correlations attenuates false positive rates caused by the length bias, but statistical power is reduced as well. Our results advocate the inspection and correction of sample-specific length biases as default steps in RNA-seq analysis pipelines and reiterate the need to account for intergene correlations when performing gene-set enrichment tests to lessen false interpretation of transcriptomic data.
PMID: 31714939
ISSN: 1545-7885
CID: 4185232