Therapeutic Potential of α7 Nicotinic Acetylcholine Receptors.

Progress in the fields of neuroscience and molecular biology has identified the forebrain cholinergic system as being important in many higher order brain functions. Further analysis of the genes encoding the nicotinic acetylcholine receptors (nAChRs) has highlighted, in particular, the role of α7 nAChRs in these higher order brain functions as evidenced by their peculiar physiologic and pharmacological properties. As this receptor has gained the attention of scientists from academia and industry, our knowledge of its roles in various brain and bodily functions has increased immensely. We have also seen the development of small molecules that have further refined our understanding of the roles of α7 nAChRs, and these molecules have begun to be tested in clinical trials for several indications. Although a large body of data has confirmed a role of α7 nAChRs in cognition, the translation of small molecules affecting α7 nAChRs into therapeutics has to date only progressed to the stage of testing in clinical trials. Notably, however, most recent human genetic and biochemical studies are further underscoring the crucial role of α7 nAChRs and associated genes in multiple organ systems and disease states. The aim of this review is to discuss our current knowledge of α7 nAChRs and their relevance as a target in specific functional systems and disease states.

Longitudinal Changes in Measured Glomerular Filtration Rate, Renal Fibrosis and Biomarkers in a Rat Model of Type 2 Diabetic Nephropathy.

BACKGROUND: Obese ZSF-1 rats display many features of human type II diabetes including nephropathy (DN). The study aimed to further understand the relevance of this model to DN, for which glomerular filtration rate (GFR), renal fibrosis and several urinary/tissue biomarkers was followed over 24 weeks in ZSF-1 rats. METHODS: Intact/sham or uninephrectomized male and female ZSF-1 rats were studied. GFR was measured by transdermal clearance of fluorescein isothiocyanate-sinistrin. Urine was collected every 2-4 weeks for biomarker analysis. Renal tissue was examined histologically for fibrosis and for levels of inflammatory and fibrotic genes. RESULTS: Male obese ZSF-1 rats demonstrated metabolic syndrome and proteinuria. Female counterparts were hyperlipidemic with delayed proteinuria, but were not hyperglycemic. Kidney hyperfiltration was observed in male obese rats in weeks 2-4 after surgery, and subsequently declined to levels significantly lower than controls. Tubulointerstitial/glomerular fibrosis in male obese rats was significantly elevated by week 12 post surgery and continued to expand in the ensuing weeks, particularly in uninephrectomized rats. Female rats had less severe fibrosis. Except for epidermal growth factor which decreased, the levels of several key inflammatory, injury and fibrotic factors were elevated in both tissue (mRNA) and urine (protein) of male obese rats. CONCLUSION: Male obese ZSF-1 rats represent an important DN model, manifesting key pathophysiological features including metabolic syndrome, proteinuria, progressive tubular and glomerular fibrosis, and transient hyperfiltration followed by progressive decline in renal function. Uninephrectomy significantly accelerated disease progression. Females were less severe in disease manifestation. Several urinary and tissue biomarkers were identified in the male obese rats that tracked with disease progression.

Modulation of phototropic responsiveness in Arabidopsis through ubiquitination of phototropin 1 by the CUL3-Ring E3 ubiquitin ligase CRL3(NPH3).

Plant phototropism is an adaptive response to changes in light direction, quantity, and quality that results in optimization of photosynthetic light harvesting, as well as water and nutrient acquisition. Though several components of the phototropic signal response pathway have been identified in recent years, including the blue light (BL) receptors phototropin1 (phot1) and phot2, much remains unknown. Here, we show that the phot1-interacting protein NONPHOTOTROPIC HYPOCOTYL3 (NPH3) functions as a substrate adapter in a CULLIN3-based E3 ubiquitin ligase, CRL3(NPH3). Under low-intensity BL, CRL3(NPH3) mediates the mono/multiubiquitination of phot1, likely marking it for clathrin-dependent internalization from the plasma membrane. In high-intensity BL, phot1 is both mono/multi- and polyubiquitinated by CRL3(NPH3), with the latter event targeting phot1 for 26S proteasome-mediated degradation. Polyubiquitination and subsequent degradation of phot1 under high-intensity BL likely represent means of receptor desensitization, while mono/multiubiquitination-stimulated internalization of phot1 may be coupled to BL-induced relocalization of hormone (auxin) transporters.

Methods for improving the quality and completeness of mortality data for American Indians and Alaska Natives.

OBJECTIVES: We describe methods used to mitigate the effect of race misclassification in mortality records and the data sets used to improve mortality estimates for American Indians and Alaska Natives (AI/ANs). METHODS: We linked US National Death Index (NDI) records with Indian Health Service (IHS) registration records to identify AI/AN deaths misclassified as non-AI/AN deaths. Analyses excluded decedents of Hispanic origin and focused on Contract Health Service Delivery Area (CHSDA) counties. We compared death rates for AI/AN persons and Whites across 6 US regions. RESULTS: IHS registration records merged to 176,137 NDI records. Misclassification of AI/AN race in mortality data ranged from 6.3% in the Southwest to 35.6% in the Southern Plains. From 1999 to 2009, the all-cause death rate in CHSDA counties for AI/AN persons varied by geographic region and was 46% greater than that for Whites. Analyses for CHSDA counties resulted in higher death rates for AI/AN persons than in all counties combined. CONCLUSIONS: Improving race classification among AI/AN decedents strengthens AI/AN mortality data, and analyzing deaths by geographic region can aid in planning, implementation, and evaluation of efforts to reduce health disparities in this population.

Diabetes-related mortality among American Indians and Alaska Natives, 1990-2009.

OBJECTIVES: We assessed diabetes-related mortality for American Indians and Alaska Natives (AI/ANs) and Whites. METHODS: Study populations were non-Hispanic AI/AN and White persons in Indian Health Service (IHS) Contract Health Service Delivery Area counties; Hispanics were excluded. We used 1990 to 2009 death certificate data linked to IHS patient registration records to identify AI/AN decedents aged 20 years or older. We examined disparities and trends in mortality related to diabetes as an underlying cause of death (COD) and as a multiple COD. RESULTS: After increasing between 1990 and 1999, rates of diabetes as an underlying COD and a multiple COD subsequently decreased in both groups. However, between 2000 and 2009, age-adjusted rates of diabetes as an underlying COD and a multiple COD remained 2.5 to 3.5 times higher among AI/AN persons than among Whites for all age groups (20-44, 45-54, 55-64, 65-74, and ≥ 75 years), both sexes, and every IHS region except Alaska. CONCLUSIONS: Declining trends in diabetes-related mortality in both AI/AN and White populations are consistent with recent improvements in their health status. Reducing persistent disparities in diabetes mortality will require developing effective approaches to not only control but also prevent diabetes among AI/AN populations.

Comparison of fecal occult blood tests for colorectal cancer screening in an Alaska Native population with high prevalence of Helicobacter pylori infection, 2008-2012.

INTRODUCTION: Alaska Native colorectal cancer (CRC) incidence and mortality rates are the highest of any ethnic/racial group in the United States. CRC screening using guaiac-based fecal occult blood tests (gFOBT) are not recommended for Alaska Native people because of false-positive results associated with a high prevalence of Helicobacter pylori-associated hemorrhagic gastritis. This study evaluated whether the newer immunochemical FOBT (iFOBT) resulted in a lower false-positive rate and higher specificity for detecting advanced colorectal neoplasia than gFOBT in a population with elevated prevalence of H. pylori infection. METHODS: We used a population-based sample of 304 asymptomatic Alaska Native adults aged 40 years or older undergoing screening or surveillance colonoscopy (April 2008-January 2012). RESULTS: Specificity differed significantly (P < .001) between gFOBT (76%; 95% CI, 71%-81%) and iFOBT (92%; 95% CI, 89%-96%). Among H. pylori-positive participants (54%), specificity of iFOBT was even higher (93% vs 69%). Overall, sensitivity did not differ significantly (P = .73) between gFOBT (29%) and iFOBT (36%). Positive predictive value was 11% for gFOBT and 32% for iFOBT. CONCLUSION: The iFOBT had a significantly higher specificity than gFOBT, especially in participants with current H. pylori infection. The iFOBT represents a potential strategy for expanding CRC screening among Alaska Native and other populations with elevated prevalence of H. pylori, especially where access to screening endoscopy is limited.

GDF15 is a dynamic biomarker of the integrated stress response in the central nervous system.

AIM: Characterize Growth Differentiation Factor 15 (GDF15) as a secreted biomarker of the integrated stress response (ISR) within the central nervous system (CNS). METHODS: We determined GDF15 levels utilizing in vitro and in vivo neuronal systems wherein the ISR was activated. Primarily, we used the murine model of vanishing white matter disease (VWMD), a neurological disease driven by persistent ISR in the CNS, to establish a link between levels of GDF15 in the cerebrospinal fluid (CSF) and ISR gene expression signature in the CNS. GDF15 was also determined in the CSF of VWM patients. RESULTS: GDF15 expression was increased concomitant to ISR activation in stress-induced primary astrocytes as well as in retinal ganglion cells following optic nerve crush, while treatment with 2Bact, a specific eIF2B activator, suppressed both the ISR and GDF15. In the VWMD model, CSF GDF15 levels corresponded with the magnitude of the ISR and were reduced by 2BAct. In VWM patients, mean CSF GDF15 was elevated >20-fold as compared to healthy controls, whereas plasma GDF15 was undifferentiated. CONCLUSIONS: These data suggest that CSF GDF15 is a dynamic marker of ISR activation in the CNS and may serve as a pharmacodynamic biomarker for ISR-modulating therapies.

Synthesis and SAR of 4-aminocyclopentapyrrolidines as N-type Ca²âº channel blockers with analgesic activity.

A novel 4-aminocyclopentapyrrolidine series of N-type Ca(2+) channel blockers have been discovered. Enantioselective synthesis of the 4-aminocyclopentapyrrolidines was enabled using N-tert-butyl sulfinamide chemistry. SAR studies demonstrate selectivity over L-type Ca(2+) channels. N-type Ca(2+) channel blockade was confirmed using electrophysiological recording techniques. Compound 25 is an N-type Ca(2+) channel blocker that produces antinociception in inflammatory and nociceptive pain models without exhibiting cardiovascular or motor liabilities.

Long-Term Outcomes of Olfactory Neuroblastoma: MD Anderson Cancer Center Experience and Review of the Literature.

OBJECTIVES/HYPOTHESIS: Olfactory neuroblastoma (ONB) is a rare sinonasal malignant neoplasm that is known to develop late recurrence. The aim of this study is to evaluate the long-term outcomes of patients with ONB and to determine the factors associated with prognosis. STUDY DESIGN: Retrospective study. METHODS: A retrospective review of the medical records of 139 patients diagnosed with ONB at MD Anderson Cancer Center was performed between 1991 and 2016. Descriptive statistics were calculated, and Kaplan-Meier curves were utilized to assess survival. RESULTS: Median follow-up time was 75 months. Overall, 129 patients (92.8%) had surgery as part of their treatment and 82 (58.9%) patients received postoperative radiation therapy (PORT) or concurrent chemoradiotherapy. Endoscopic approaches were utilized for 72 patients, 69.4% of whom had pure endoscopic endonasal approaches. Five-year overall survival and disease-specific survival were 85.6% and 93.4%, respectively. Recurrence rate was 39.6% with a median time to recurrence of 42 months. Among the 31 patients who received elective nodal irradiation (ENI), two patients developed neck recurrence (6.4%) compared with 20 who developed neck recurrence when ENI was omitted (34.4%) (P = .003). Advanced Kadish stage, orbital invasion, intracranial invasion, and presence of cervical lymphadenopathy at the time of presentation were significantly associated with poor survival. CONCLUSION: ONB has an excellent survival. Surgical resection with PORT when indicated is the mainstay of treatment. Endoscopic approaches can be used as a good tool. Elective neck irradiation reduces the risk of nodal recurrence among patients with clinically N0 neck. Despite the excellent survival, recurrence rate remains high and delayed, highlighting the need for long-term surveillance. LEVEL OF EVIDENCE: Level 4 Laryngoscope, 132:290-297, 2022.

Comparative analysis of inactivated-state block of N-type (Ca(v)2.2) calcium channels.

OBJECTIVE: The aim of this study was to compare a diverse set of peptide and small-molecule calcium channel blockers for inactivated-state block of native and recombinant N-type calcium channels using fluorescence-based and automated patch-clamp electrophysiology assays. METHODS: The pharmacology of calcium channel blockers was determined at N-type channels in IMR-32 cells and in HEK cells overexpressing the inward rectifying K(+) channel Kir2.1. N-type channels were opened by increasing extracellular KCl. In the Kir2.1/N-type cell line the membrane potential could be modulated by adjusting the extracellular KCl, allowing determination of resting and inactivated-state block of N-type calcium channels. The potency and degree of state-dependent inhibition of these blockers were also determined by automated patch-clamp electrophysiology. RESULTS: N-type-mediated calcium influx in IMR-32 cells was determined for a panel of blockers with IC(50) values of 0.001-7 µM and this positively correlated with inactivated-state block of recombinant channels measured using electrophysiology. The potency of several compounds was markedly weaker in the state-dependent fluorescence-based assay compared to the electrophysiology assay, although the degree of state-dependent blockade was comparable. CONCLUSIONS: The present data demonstrate that fluorescence-based assays are suitable for assessing the ability of blockers to selectively interact with the inactivated state of the N-type channel.

Synthesis and in vitro activity of N-benzyl-1-(2,3-dichlorophenyl)-1H-tetrazol-5-amine P2X(7) antagonists.

Synthesis and biological evaluation of a novel class of substituted N-benzyl-1-(2,3-dichlorophenyl)-1H-tetrazol-5-amine derivatives resulted in the identification of potent P2X(7) antagonists. These compounds were assayed for activity at both the human and rat P2X(7) receptors. On the benzyl moiety, a variety of functional groups were tolerated, including both electron-withdrawing and electron-donating substituents. Ortho-substitution on the benzyl group provided the greatest potency. The ortho-substituted analogs showed approximately 2.5-fold greater potency at human compared to rat P2X(7) receptors. Compounds 12 and 38 displayed hP2X(7)pIC(50)s>7.8 with less than 2-fold difference in potency at the rP2X(7).

NRF2 activator A-1396076 ameliorates inflammation in autoimmune disease models by inhibiting antigen dependent T cell activation.

Nuclear factor (erythroid-derived 2) like 2 (NRF2) is a nuclear transcription factor activated in response to oxidative stress that induces a gene program that dampens inflammation and can limit cell damage that perpetuates the inflammatory response. We have identified A-1396076, a potent and selective NRF2 activator with demonstrated KEAP1 binding and modulation of cellular NRF2 mediated effects. In vivo administration of A-1396076 inhibits inflammation across several rodent models of autoimmunity when administered at or before the time of antigen challenge while also inducing NRF2 modulated gene transcription in the liver of the animals. It was not effective when administered after the time of antigen challenge or in a T cell independent model of arthritis induced by passive transfer of anti-collagen antibodies. A-1396076 inhibited antigen dependent T cell activation as measured by IFN-γ production in an ex vivo re-stimulation assay and following anti-CD3 challenge of MOG-sensitized mice. A-1396076 reduced costimulatory molecule expression on dendritic cells in the lungs of OVA LPS challenged mice suggesting that the mechanism of T cell inhibition was mediated at least partially by interfering with antigen presentation. These data suggest that NRF2 activation may be an effective strategy to dampen inflammation for treatment of autoimmune disease.

Development of Orally Efficacious Allosteric Inhibitors of TNFα via Fragment-Based Drug Design.

Tumor necrosis factor α (TNFα) is a soluble cytokine that is directly involved in systemic inflammation through the regulation of the intracellular NF-κB and MAPK signaling pathways. The development of biologic drugs that inhibit TNFα has led to improved clinical outcomes for patients with rheumatoid arthritis and other chronic autoimmune diseases; however, TNFα has proven to be difficult to drug with small molecules. Herein, we present a two-phase, fragment-based drug discovery (FBDD) effort in which we first identified isoquinoline fragments that disrupt TNFα ligand-receptor binding through an allosteric desymmetrization mechanism as observed in high-resolution crystal structures. The second phase of discovery focused on the de novo design and optimization of fragments with improved binding efficiency and drug-like properties. The 3-indolinone-based lead presented here displays oral, in vivo efficacy in a mouse glucose-6-phosphate isomerase (GPI)-induced paw swelling model comparable to that seen with a TNFα antibody.

Activated N-formyl peptide receptor and high-affinity IgE receptor occupy common domains for signaling and internalization.

Immune cells display multiple cell surface receptors that integrate signals for survival, proliferation, migration, and degranulation. Here, immunogold labeling is used to map the plasma membrane distributions of two separate receptors, the N-formyl peptide receptor (FPR) and the high-affinity IgE receptor (FepsilonRI). We show that the FPR forms signaling clusters in response to monovalent ligand. These domains recruit Gi, followed by the negative regulatory molecule arrestin2. There are low levels of colocalization of FPR with FcepsilonRI in unstimulated cells, shown by computer simulation to be a consequence of receptor density. Remarkably, there is a large increase in receptor coclustering when cells are simultaneously treated with N-formyl-methionyl-leucyl-phenylalanine and IgE plus polyvalent antigen. The proximity of two active receptors may promote localized cross-talk, leading to enhanced inositol-(3,4,5)-trisphosphate production and secretion. Some cointernalization and trafficking of the two receptors can be detected by live cell imaging, but the bulk of FPR and FcepsilonRI segregates over time. This segregation is associated with more efficient internalization of cross-linked FcepsilonRI than of arrestin-desensitized FPR. The observation of receptors in lightly coated membrane invaginations suggests that, despite the lack of caveolin, hematopoietic cells harbor caveolae-like structures that are candidates for nonclathrin-mediated endocytosis.

Small Molecule Phenotypic Screen Identifies Novel Regulators of LDLR Expression.

Alzheimer's Disease (AD) is a progressive neurodegenerative disease and the most common cause of dementia. The current treatment options for AD are limited to ameliorating cognitive decline temporarily and not reversing or preventing the progression of dementia. Hence, more effective therapeutic strategies are needed to combat this devastating disease. The low-density lipoprotein receptor has been shown to modulate the neuronal metabolism of cholesterol and apolipoprotein E, a major genetic risk factor for AD. LDLR overexpression in mice has been shown to increase amyloid-ß clearance and reduce amyloid deposition. We conducted a phenotypic screen to identify novel signaling pathways and targets that regulate LDLR expression in glial cells using an annotated compound library of approximately 29 000 compounds. The screen identified novel targets such as polo like kinase 1 (PLK1), activin receptor like kinase 5 (ALK5), and serotonin transporter (SERT). We used genetic, chemical biology and pathway analysis to confirm the target hypothesis. This work highlights that phenotypic screening is a promising strategy to identify novel mechanisms and targets for therapeutic intervention of complex neurodegenerative disorders.

[3H]A-804598 ([3H]2-cyano-1-[(1S)-1-phenylethyl]-3-quinolin-5-ylguanidine) is a novel, potent, and selective antagonist radioligand for P2X7 receptors.

ATP-sensitive P2X7 receptors are localized on cells of immunological origin including peripheral macrophages and glial cells in the CNS. Activation of P2X7 receptors leads to rapid changes in intracellular calcium concentrations, release of the pro-inflammatory cytokine IL-1beta, and following prolonged agonist exposure, the formation of cytolytic pores in plasma membranes. Data from gene knockout studies and recently described selective antagonists indicate a role for P2X7 receptor activation in inflammation and pain. While several species selective P2X7 antagonists exist, A-804598 represents a structurally novel, competitive, and selective antagonist that has equivalent high affinity at rat (IC50 = 10 nM), mouse (IC50 = 9 nM) and human (IC50 = 11 nM) P2X7 receptors. A-804598 also potently blocked agonist stimulated release of IL-1beta and Yo-Pro uptake from differentiated THP-1 cells that natively express human P2X7 receptors. A-804598 was tritiated ([3H]A-804598; 8.1Ci/mmol) and utilized to study recombinant rat P2X7 receptors expressed in 1321N1 cells. [3H]A-804598 labeled a single class of high affinity binding sites (Kd=2.4 nM and apparent Bmax=0.56 pmol/mg). No specific binding was observed in untransfected 1321N1 cells. The pharmacological profile for P2X antagonists to inhibit [3H]A-804598 binding correlated with their ability to block functional activation of P2X7 receptors (r=0.95, P<0.05). These data demonstrate that A-804598 is one of the most potent and selective antagonists for mammalian P2X7 receptors described to date and [3H]A-804598 is a high affinity antagonist radioligand that specifically labels rat P2X7 receptors.

Understanding phototropism: from Darwin to today.

Few individuals have had the lasting impact on such a breadth of science as Charles Darwin. While his writings about time aboard the HMS Beagle, his study of the Galapagos islands (geology, fauna, and flora), and his theories on evolution are well known, less appreciated are his studies on plant growth responses to a variety of environmental stimuli. In fact, Darwin, together with the help of his botanist son Francis, left us an entire book, 'The power of movements in plants', describing his many, varied, and insightful observations on this topic. Darwin's findings have provided an impetus for an entire field of study, the study of plant tropic responses, or differential growth (curvature) of plant organs in response to directional stimuli. One tropic response that has received a great deal of attention is the phototropic response, or curvature response to directional light. This review summarizes many of the most significant advancements that have been made in our understanding of this response and place these recent findings in the context of Darwin's initial observations.

Deletion of 1p32-p36 is the most frequent genetic change and poor prognostic marker in adenoid cystic carcinoma of the salivary glands.

PURPOSE: Adenoid cystic carcinoma (ACC) is a relatively uncommon salivary gland malignancy known for its protean phenotypic features and pernicious clinical behavior. Currently, no effective therapy is available for patients with advanced nonresectable, recurrent, and/or metastatic disease. The purpose of this study is to identify prognostic factors other than tumor stage that can be used to predict the outcome of the patients with ACC. EXPERIMENTAL DESIGN: We used comparative genomic hybridization (CGH) to identify copy number aberrations in 53 primary ACCs. Array CGH and fluorescence in situ hybridization analysis was used to validate CGH results on selected cases. We correlated these copy number aberrations with clinicopathologic factors using Pearson's chi2 or by the two-tailed Fisher exact test. The disease-specific survival and disease-free intervals were generated by the Kaplan-Meier product limit method. RESULTS: Chromosomal losses (n = 134) were more frequent than gains (n = 74). The most frequent genetic change was the loss of 1p32-p36 in 44% of the cases followed by 6q23-q27, and 12q12-q14. The most frequently gained chromosomal regions were 8 and 18. Of the chromosomal aberrations, loss of 1p32-p36 was the only abnormality significantly associated with patient's outcome. CONCLUSIONS: This study, for the first time, identifies loss of 1p32-p36 as a significant aberration in ACC. Molecular characterization of 1p32-36 region using the available genomic technologies may lead to the identification of new genes critical to the development of novel therapeutic targets for this disease copy number aberration.

Characterization of psoriasiform dermatitis induced by systemic injection of interleukin-23 minicircles in mice.

The interleukin (IL)-23/IL-17 axis plays a central role in the pathogenesis of psoriasis and is elevated in lesional psoriatic skin. Different murine models have been developed to mimic this pathophysiology each carrying specific merits and limitations. In an attempt to address some of these limitations, B10.RIII mice received a single hydrodynamic injection of IL-23 minicircles (MC) to induce hepatic transcription and the endogenous production of IL-23. Plasma and ear IL-23 levels were dose-dependently (0.3-3 µg) increased in MC injected mice and were sustained over the 14-day study duration. Beginning on day 7 post-injection, mice developed dose-related ear inflammation, histologically confirmed increases in epidermal and dermal area, as well as enhanced neutrophil and macrophage content. Flow cytometry demonstrated increased levels of granulocytes, T cells and monocytes/macrophages in the ear skin, with T cells identified as the main cellular source of IL-17A. Evaluation of mRNA and protein showed time-dependent, increased levels of the IL-23/IL-17 pathway and inflammatory/microbial cytokines/chemokines in the ear which differed kinetically from circulating levels. An anti-IL-23p40 antibody was assessed following both prophylactic administration and administration once the disease was established. Prophylactic dosing completely prevented the development of the ear phenotype across endpoints. Treatment administration showed a dose-related response, with a maximum inhibition of 64-94%, depending on endpoint. These data demonstrate that the IL-23 MC model is a useful approach to study IL-23/IL-17-driven skin inflammation and may facilitate preclinical assessment of novel therapies.

Small Molecule and Pooled CRISPR Screens Investigating IL17 Signaling Identify BRD2 as a Novel Contributor to Keratinocyte Inflammatory Responses.

Interleukin-17A (IL17A) plays a critical role in the development of numerous autoimmune diseases, including psoriasis. The clinical success of IL17A neutralizing biologics in psoriasis has underlined its importance as a drug discovery target. While many studies have focused on the differentiation and trafficking of IL17A producing T-helper 17 cells, less is known about IL17A-initiated signaling events in stromal and parenchymal cells leading to psoriatic phenotypes. We sought to discover signaling nodes downstream of IL17A contributing to disease pathogenesis. Using IL17A and tumor necrosis factor α (TNF) to stimulate primary human epidermal keratinocytes, we employed two different phenotypic screening approaches. First, a library of ∼22000 annotated compounds was screened for reduced secretion of the pro-inflammatory chemokine IL8. Second, a library of 729 kinases was screened in a pooled format by utilizing CRISPR-Cas9 and monitoring IL8 intracellular staining. The highest-ranking novel hits identified in both screens were the bromodomain and extra-terminal domain (BET) family proteins and bromodomain-containing protein 2 (BRD2), respectively. Comparison of BRD2, BRD3, and BRD4 silencing with siRNA and CRISPR confirmed that BRD2 was responsible for mediating IL8 production. Pan-BRD inhibitors and BRD2 knockout also reduced IL17A/TNF-mediated CXC motif chemokines 1/2/6 (CXCL1/2/6) and granulocyte colony stimulating factor (G-CSF) production. In RNA-Seq analysis, 438 IL17A/TNF dependent genes were reduced in BRD2-deficient primary keratinocytes. KEGG pathway analysis of these genes showed enrichment in TNF signaling and rheumatoid arthritis relevant genes. Moreover, a number of genes important for keratinocyte homeostasis and cornification were dysregulated in BRD2-deficient keratinocytes. In IL17A/TNF/IL22 stimulated three-dimensional organotypic raft cultures, pan-BRD inhibition reduced inflammatory factor production but elicited aberrant cornification, consistent with RNA-Seq analysis. These studies highlight a novel role for BRDs and BRD2 in particular in IL17A-mediated inflammatory signaling.