Publications by authors named "Shaun Stauffer"

Introduction: WDR5 is an epigenetic scaffolding protein that has attracted significant interest as an anti-cancer drug target, especially in MLL-rearranged leukemias. The most druggable 'WIN-site' on WDR5, which tethers WDR5 to chromatin, has been successfully targeted with multiple classes of exquisitely potent small-molecule protein-protein interaction inhibitors. Earlier progress has also been made on the development of WDR5 degraders and inhibitors at the 'WBM-site' on the opposite face of WDR5.

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Herein we detail the of VU0467319 (VU319), an M Positive Allosteric Modulator (PAM) clinical candidate that successfully completed a Phase I Single Ascending Dose (SAD) clinical trial. VU319 () is a moderately potent M PAM (M PAM EC = 492 nM ± 2.9 nM, 71.

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Interferon (IFN)-stimulated gene 15 (ISG15), a ubiquitin-like protein, is covalently conjugated to host immune proteins such as MDA5 and IRF3 in a process called ISGylation, thereby promoting type I IFN induction to limit the replication of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, whether SARS-CoV-2 proteins can be directly targeted for ISGylation remains elusive. In this study, we identified the nucleocapsid (N) protein of SARS-CoV-2 as a major substrate of ISGylation catalyzed by the host E3 ligase HERC5; however, N ISGylation is readily removed through deISGylation by the papain-like protease (PLpro) activity of NSP3.

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Interferon (IFN)-stimulated gene 15 (ISG15), a ubiquitin-like protein, is covalently conjugated to host (immune) proteins such as MDA5 and IRF3 in a process called ISGylation, thereby limiting the replication of Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, whether SARS-CoV-2 proteins can be directly targeted for ISGylation remains elusive. In this study, we identified the nucleocapsid (N) protein of SARS-CoV-2 as a major substrate of ISGylation catalyzed by the host E3 ligase HERC5; however, N ISGylation is readily removed through de-ISGylation by the papain-like protease (PLpro) activity of NSP3.

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Purpose: There are no effective treatment options for patients with aggressive epithelioid hemangioendothelioma (EHE) driven by the TAZ-CAMTA1 (TC) fusion gene. Here, we aimed to understand the regulation of TC using pharmacologic tools and identify vulnerabilities that can potentially be exploited for the treatment of EHE.

Experimental Design: TC is a transcriptional coregulator; we hypothesized that compounds that reduce TC nuclear levels, either through translocation of TC to the cytoplasm, or through degradation, would render TC less oncogenic.

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Citron kinase (CITK) is an AGC-family serine/threonine kinase that regulates cytokinesis. Despite knockdown experiments implicating CITK as an anticancer target, no selective CITK inhibitors exist. We transformed a previously reported kinase inhibitor with weak off-target CITK activity into a first-in-class CITK chemical probe, .

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Unlabelled: Prostate cancer remains the second leading cause of cancer death in men in Western cultures. A deeper understanding of the mechanisms by which prostate cancer cells divide to support tumor growth could help devise strategies to overcome treatment resistance and improve survival. Here, we identified that the mitotic AGC family protein kinase citron kinase (CIT) is a pivotal regulator of prostate cancer growth that mediates prostate cancer cell interphase progression.

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Cancer stem cells drive tumor growth and survival via self-renewal and therapeutic resistance, but the upstream mechanisms are not well defined. In this issue of PLOS Biology, a study in colon cancer reveals a new signalling network that links epigenetic regulation to these phenotypes.

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Direct targeting of essential viral enzymes such as proteases, polymerases, and helicases has long been the major focus of antiviral drug design. Although successful for some viral enzymes, targeting viral helicases is notoriously difficult to achieve, demanding alternative strategies. Here, we show that the NS3 helicase of Zika virus (ZIKV) undergoes acetylation in its RNA-binding tunnel.

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α-Adrenergic Receptors (ARs) regulate the sympathetic nervous system by the binding of norepinephrine (NE) and epinephrine (Epi) through different subtypes (α, α, α). α-AR activation is hypothesized to be memory forming and cognitive enhancing but drug development has been stagnant due to unwanted side effects on blood pressure. We recently reported the pharmacological characterization of the first positive allosteric modulator (PAM) for the α-AR with predictive pro-cognitive and memory properties.

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Starting from compound (CCF0058981), a structure-based optimization of the P1 subsite was performed against the severe acute respiratory syndrome coronavirus (SARS-CoV-2) main protease (3CL). Inhibitor and the compounds disclosed bind to 3CL using a non-covalent mode of action that utilize a His163 H-bond interaction in the S1 subpocket. In an effort to examine more structurally diverse P1 groups a number of azoles and heterocycles were designed.

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The Hippo signaling pathway is a highly conserved pathway that plays important roles in the regulation of cell proliferation and apoptosis. Transcription factors TEAD1-4 and transcriptional coregulators YAP/TAZ are the downstream effectors of the Hippo pathway and can modulate Hippo biology. Dysregulation of this pathway is implicated in tumorigenesis and acquired resistance to therapies.

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Glioblastomas (GBMs) are heterogeneous, treatment-resistant tumors driven by populations of cancer stem cells (CSCs). However, few molecular mechanisms critical for CSC population maintenance have been exploited for therapeutic development. We developed a spatially resolved loss-of-function screen in GBM patient-derived organoids to identify essential epigenetic regulators in the SOX2-enriched, therapy-resistant niche and identified WDR5 as indispensable for this population.

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Prostate cancer is highly dependent on androgens and the androgen receptor (AR). Hormonal therapies inhibit gonadal testosterone production, block extragonadal androgen biosynthesis, or directly antagonize AR. Resistance to medical castration occurs as castration-resistant prostate cancer (CRPC) and is driven by reactivation of the androgen-AR axis.

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Article Synopsis
  • α-Adrenergic Receptors (ARs) are G-protein coupled receptors that play a key role in regulating the sympathetic nervous system, but drug development for these receptors is challenging due to issues with blood pressure.
  • The study introduces Cmpd-3, a newly developed positive allosteric modulator (PAM) of α-ARs, which binds effectively to ARs and enhances norepinephrine's effects without acting like a traditional agonist that raises blood pressure.
  • Cmpd-3 is unique in its ability to selectively enhance receptor signaling at low concentrations, promising better therapeutic options for various diseases without the side effects often associated with existing drugs targeting α-ARs.
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We developed an endophenotype disease module-based methodology for Alzheimer's disease (AD) drug repurposing and identified sildenafil as a potential disease risk modifier. Based on retrospective case-control pharmacoepidemiologic analyses of insurance claims data for 7.23 million individuals, we found that sildenafil usage was significantly associated with a 69% reduced risk of AD (hazard ratio = 0.

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Alzheimer's disease (AD) has been linked to multiple immune system-related genetic variants. Triggering receptor expressed on myeloid cells 2 (TREM2) genetic variants are risk factors for AD and other neurodegenerative diseases. In addition, soluble TREM2 (sTREM2) isoform is elevated in cerebrospinal fluid in the early stages of AD and is associated with slower cognitive decline in a disease stage-dependent manner.

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As blood transitions from steady laminar flow (S-flow) in healthy arteries to disturbed flow (D-flow) in aneurysmal arteries, platelets are subjected to external forces. Biomechanical platelet activation is incompletely understood and is a potential mechanism behind antiplatelet medication resistance. Although it has been demonstrated that antiplatelet drugs suppress the growth of abdominal aortic aneurysms (AAA) in patients, we found that a certain degree of platelet reactivity persisted in spite of aspirin therapy, urging us to consider additional antiplatelet therapeutic targets.

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Metastatic outgrowth is supported by metabolic adaptations that may differ from the primary tumor of origin. However, it is unknown if such adaptations are therapeutically actionable. Here we report a novel aminopyridine compound that targets a unique Phosphogluconate Dehydrogenase (PGD)-dependent metabolic adaptation in distant metastases from pancreatic cancer patients.

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Starting from the MLPCN probe compound ML300, a structure-based optimization campaign was initiated against the recent severe acute respiratory syndrome coronavirus (SARS-CoV-2) main protease (3CL). X-ray structures of SARS-CoV-1 and SARS-CoV-2 3CL enzymes in complex with multiple ML300-based inhibitors, including the original probe ML300, were obtained and proved instrumental in guiding chemistry toward probe compound (CCF0058981). The disclosed inhibitors utilize a noncovalent mode of action and complex in a noncanonical binding mode not observed by peptidic 3CL inhibitors.

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Prostate cancer resistance to next-generation hormonal treatment with enzalutamide is a major problem and eventuates into disease lethality. Biologically active glucocorticoids that stimulate glucocorticoid receptor (GR) have an 11β-OH moiety, and resistant tumors exhibit loss of 11β-HSD2, the oxidative (11β-OH → 11-keto) enzyme that normally inactivates glucocorticoids, allowing elevated tumor glucocorticoids to drive resistance by stimulating GR. Here, we show that up-regulation of hexose-6-phosphate dehydrogenase (H6PD) protein occurs in prostate cancer tissues of men treated with enzalutamide, human-derived cell lines, and patient-derived prostate tissues treated ex vivo with enzalutamide.

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Metastatic castration-resistant prostate cancer poses a serious clinical problem with poor outcomes and remains a deadly disease. New targeted treatment options are urgently needed. PSMA is highly expressed in prostate cancer and has been an attractive biomarker for the treatment of prostate cancer.

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Allosteric modulation of GPCRs represents an increasingly explored approach in drug development. Due to complex pharmacology, however, the relationship(s) between modulator properties determined with concentration-effect phenomena is frequently unclear. We investigated key pharmacological properties of a set of metabotropic glutamate receptor 5 (mGlu) positive allosteric modulators (PAMs) and their relevance to concentration-response relationships.

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The frequent deregulation of MYC and its elevated expression via multiple mechanisms drives cells to a tumorigenic state. Indeed, MYC is overexpressed in up to ∼50% of human cancers and is considered a highly validated anticancer target. Recently, we discovered that WD repeat-containing protein 5 (WDR5) binds to MYC and is a critical cofactor required for the recruitment of MYC to its target genes and reported the first small molecule inhibitors of the WDR5-MYC interaction using structure-based design.

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