Biology subjects

Gordon, B.

Publications and source records attributed to Gordon, B..

10 recordsLinked to original sources

bioRxiv2026

RORγ Inverse Agonism Redirects Tumour-Conditioned Emergency Myelopoiesis and Attenuates Established Tumour Progression

Systemic inflammation is associated with poor outcomes in gastroesophageal adenocarcinoma (GEA), but how it contributes to disease progression remains unclear. We investigated retinoic acid receptor-related orphan receptor gamma (ROR{gamma}) as a regulator of tumour-conditioned myeloid responses. In treatment-naive GEA patients, elevated circulating neutrophil-to-lymphocyte ratio (cNLR) tracked with circulating ROR{gamma} positive neutrophils and tumoural spatial organization of ROR{gamma} positive myeloid cells, rather than neutrophil abundance. In syngeneic tumour models, pharmacologic ROR{gamma} inverse agonism altered marrow progenitor composition before tumour-growth divergence and remodeled myeloid organization across bone marrow, tumour and lung despite no endpoint change in circulating neutrophil proportions, which did not capture the earlier marrow response or subsequent tumour trajectory. ROR{gamma} perturbation enhanced longitudinal tumour control with PD-L1 blockade, whereas effects on metastatic establishment depended on tumour conditioning and treatment timing. These findings identify ROR{gamma} associated myeloid programming as a therapeutically tractable, context-dependent regulator linking systemic inflammation, hematopoiesis, tissue immune organization, and cancer progression.

cancer biology↗

bioRxiv2026

High Dimensional Immune Profiling Reveals CD39 as a Correlate of Tuberculosis Disease Severity

Immune biomarkers of tuberculosis (TB) disease severity present a challenging area of research that remains poorly understood. New technologies are able to perform larger, unbiased studies that can unravel the complex host-pathogen dynamics occurring during a Mycobacterium tuberculosis infection, the causative agent of TB. In this study, we designed a high dimensional approach combining viable bacterial burden (CFU, colony forming units) with time-of-flight mass cytometry (CyTOF) analysis to profile differences in cell-type abundance and cell-type specific protein expression during states of low, intermediate and high TB disease burden. Broadly, we segregated cell-type specific immune responses into those driven by bacterial burden and/or the mycobacterial infection strain. Interrogating these immune signatures allowed us to identify ATP-catabolizing protein CD39 as a correlate of disease severity. Treatment of mice with a small molecule inhibitor of CD39 promoted effector T cell functions and CD4 T cell expansion during Mtb infection. Collectively, our data defines the differential lung immune environment between various mycobacterial disease severity states and uncovers a potential immune biomarker of infection and therapeutic immunomodulating target to aid in the treatment of TB.

immunology↗

bioRxiv2024

Evidence for distinct networks underlying symptom clusters of posttraumatic stress disorder

BackgroundClinical and psychometric evidence has long supported a multidimensional model of PTSD, with symptom subcategories derived from factor analytic methods. Although research on the biological bases of PTSD as a unitary construct is profuse, comparatively few studies have examined the neural mechanisms underlying subcategories of PTSD symptoms. The present study aimed to provide the first evidence of causal relationships between brain structure and PTSD symptom subcategories, using a lesion-behavior mapping approach. MethodsUsing a group of male combat veterans with focal penetrating traumatic brain injuries (n = 177), we determined the effects of focal damage on the PTSD symptom subcategories of hyperarousal, avoidance, and re-experiencing. ResultsOur findings revealed two distinct networks that underlie symptom subcategories of PTSD: (1) an amygdala-ventromedial prefrontal cortex network underlying hyperarousal and avoidance symptoms, in which amygdala damage acts as a risk factor for the development of these symptoms, while vmPFC damage acts as a protective factor against the same symptoms; and (2) a hippocampal network underlying re-experiencing and avoidance, in which hippocampal damage acts as a protective factor against these symptoms. ConclusionsThe present study provides novel insights regarding the causal role of key brain regions in the heterogeneous expression of PTSD symptoms. Results not only contribute to a more complete picture of the neural mechanisms underlying PTSD, but may also aid in the future development of individualized therapeutic strategies that target specific symptom profiles.

neuroscience↗

bioRxiv2024

Preclinical Pediatric Molecular Analysis for Therapy Choice (MATCH)

Pediatric solid tumors arise from diverse tissues during development and exhibit a wide range of molecular, cellular and genetic features. This diversity, combined with the low incidence of pediatric cancer makes it increasingly difficult to personalize therapy for individual patients based on the unique features of their tumors. Therefore, well-credentialed preclinical models that capture the diversity and heterogeneity of pediatric solid tumors are essential for identifying molecular targeted therapeutics for precision medicine. Here, we report 281 orthotopic patient derived xenografts (O-PDXs) from 224 patients representing 24 different types of pediatric solid tumors. We have performed genomic characterization of the O-PDXs and compared them to their corresponding patient tumors. To demonstrate the feasibility and utility of using such a diverse collection of O-PDXs in preclinical studies, we performed a preclinical pediatric precision medicine trial based on the NCI-COG Pediatric MATCH trial enrollment criteria. We also tested molecular targeted therapy for a novel oncogenic fusion recently reported in pediatric melanoma and precision drug delivery using nano-liposomal irinotecan. Our studies demonstrate the value of large, well-credentialed preclinical models for future precision medicine in pediatric oncology using single agents, drug combinations and novel drug formulations. Translational RelevanceThis study demonstrates the value of utilizing fully characterized preclinical models of pediatric solid tumors to evaluate the response to precision medicine approaches. Our results demonstrate the importance of performing comprehensive preclinical testing using multiple orthotopic patient derived xenografts to validate and prioritize vulnerabilities identified through genomic or integrated analyses which can be translated into clinical trials. Importantly, this study identified combinations using nano-liposomal irinotecan in a precision drug delivery approach that may benefit pediatric solid tumor patients. In addition, all models and their associated data are made freely available to the scientific community through the Childhood Solid Tumor Network.

cancer biology↗

bioRxiv2023

Functional variations in gamma-secretase activity are critical determinants of the clinical, biomarker, and cognitive progression of autosomal dominant Alzheimer's disease

BackgroundThe balance between production, clearance, and toxicity of A{beta} peptides is central to Alzheimers disease (AD) pathobiology. Though highly variable in terms of age at symptom onset (AAO), hundreds of variants in PSEN1 cause autosomal dominant forms of AD (ADAD) with nearly complete penetrance. PSEN1 forms the catalytic core of the {gamma}-secretase complex and thereby directly mediates the production of longer, aggregation-prone A{beta} peptides relative to shorter, non-aggregating peptides. We hypothesized that the broad AAO and biomarker heterogeneity seen across ADAD would be predictable based on mutation-specific differences in the production of A{beta} species. MethodsA{beta}-37, 38, 40, 42, and 43 production was quantified from 161 unique PSEN1 variants expressed in HEK293 cells. Prediction of AAO was carried out in 106 variants with available AAO and then replicated in 55 variants represented across 190 PSEN1 mutation carriers who have detailed cognitive and biomarker data from the Dominantly Inherited Alzheimers Network (DIAN). ResultsVariations in A{beta} production across the 161 mutations examined in cell-based models were highly predictive of AAO. In those with corresponding in vivo data from the DIAN study, our cell-based {gamma}-secretase composite was strongly associated with biomarker and cognitive trajectories. ConclusionsThese findings elucidate the critical link between {gamma}-secretase function, A{beta} production, and AD progression and offer mechanistic support for the amyloid hypothesis. The approach used here represents a powerful tool to account for heterogeneity in disease progression in ADAD clinical trials and to assess the pathogenicity of variants of unknown significance or with limited family history.

neuroscience↗

bioRxiv2023

Paridiprubart inhibits TLR4-dependant NF-κB activation by multiple pathogens

Respiratory pathogens such as SARS-CoV-2 and influenza can activate an exaggerated inflammatory response (cytokine storm) in the lungs that may result in acute respiratory distress syndrome (ARDS), hospitalization, and death. Therapies that target a specific pathogen (i.e. anti-virals) must, by nature, be selected after a specific diagnosis and may become ineffective due to pathogen evolution. An alternate strategy is to counter the exaggerated innate immune response present in ARDS patients using host-directed drug therapies that are agnostic to the infectious agent to overcome both of these challenges. Originally described as the innate immune receptor for lipopolysaccharide (LPS), Toll-like receptor 4 (TLR4) is now understood to be an important mediator of inflammation caused by a variety of pathogen-associated molecular patterns (PAMPs) and host-derived damage-associated molecular patterns (DAMPs). Here we show that paridiprubart, a monoclonal antibody that prevents TLR4 dimer formation, inhibits the response to TLR4 agonists including LPS, the SARS-CoV-2 spike protein, the DAMP high mobility group box 1 (HMGB1), as well as the NF-{kappa}B response to infection by both viral and bacterial pathogens. Notable in this regard, we demonstrate that SARS-CoV-2 increases HMGB1 levels, and that paridiprubart inhibits both the SARS-CoV-2 and HMGB1-triggered NF-{kappa}B response, illustrating its potential to suppress this self-amplifying inflammatory signal. We also observed that the inhibitory effect of paridiprubart is apparent when cells are exposed to the SARS-CoV-2 spike protein, which is itself a direct TLR4 agonist. In the context of active infection, paridiprubart suppressed the NF-{kappa}B-dependent response elicited by infection with SARS-CoV-2, the seasonal coronavirus 229E, influenza A virus or Haemophilus influenzae, a gram-negative bacterial pathogen. Combined, these findings reinforce the central role played by TLR4 in the inflammatory response to infection by diverse pathogens, and demonstrates the protective potential of paridiprubart-dependent inhibition of pathogenic TLR4 responses.

immunology↗

bioRxiv2023

The seminal odorant binding protein Obp56g is required for mating plug formation and male fertility in Drosophila melanogaster

In Drosophila melanogaster and other insects, the seminal fluid proteins (SFPs) and male sex pheromones that enter the female with sperm during mating are essential for fertility and induce profound post-mating effects on female physiology and behavior. The SFPs in D. melanogaster and other taxa include several members of the large gene family known as odorant binding proteins (Obps). Previous work in Drosophila has shown that some Obp genes are highly expressed in the antennae and can mediate behavioral responses to odorants, potentially by binding and carrying these molecules to odorant receptors. These observations have led to the hypothesis that the seminal Obps might act as molecular carriers for pheromones or other compounds important for male fertility in the ejaculate, though functional evidence in any species is lacking. Here, we used RNAi and CRISPR/Cas9 generated mutants to test the role of the seven seminal Obps in D. melanogaster fertility and the post-mating response (PMR). We found that Obp56g is required for male fertility and the induction of the PMR, whereas the other six genes had no effect on fertility when mutated individually. Obp56g is expressed in the males ejaculatory bulb, an important tissue in the reproductive tract that synthesizes components of the mating plug. We found males lacking Obp56g fail to form a mating plug in the mated females reproductive tract, leading to ejaculate loss and reduced sperm storage. We also examined the evolutionary history of these seminal Obp genes, as several studies have documented rapid evolution and turnover of SFP genes across taxa. We found extensive lability in gene copy number and evidence of positive selection acting on two genes, Obp22a and Obp51a. Comparative RNAseq data from the male reproductive tract of multiple Drosophila species revealed that Obp56g shows high male reproductive tract expression only in species of the melanogaster and obscura groups, though conserved head expression in all species tested. Together, these functional and expression data suggest that Obp56g may have been co-opted for a reproductive function over evolutionary time.

genetics↗

bioRxiv2021

The Myogenesis Program Drives Clonal Selection and Drug Resistance in Rhabdomyosarcoma

Rhabdomyosarcoma (RMS) is a pediatric cancer with features of skeletal muscle; patients with unresectable or metastatic RMS fare poorly due to high rates of disease recurrence. Here, we use single cell and single nucleus RNA-sequencing to show that RMS tumors recapitulate the spectrum of embryonal myogenesis. Using matched patient samples from a clinical trial and orthotopic patient-derived xenografts (O-PDXs), we show chemotherapy eliminates the most proliferative component with features of myoblasts; after treatment, the quiescent immature population with features of paraxial mesoderm expands to reconstitute the developmental hierarchy of the original tumor. We discovered that this paraxial mesoderm population is dependent on EGFR signaling and is sensitive to EGFR inhibitors. Taken together, this data serves as a proof-of-concept that targeting each developmental state in RMS is an effective strategy for improving outcomes by preventing disease recurrence.

cancer biology↗

bioRxiv2021

The chemotherapeutic CX-5461 primarily targets TOP2B and exhibits selective activity in high-risk neuroblastoma.

Survival in high-risk pediatric neuroblastoma has remained around 50% for the last 20 years, with immunotherapies and targeted therapies having had minimal impact. Here, we identify the small molecule CX-5461 as selectively cytotoxic to high-risk neuroblastoma and synergistic with low picomolar concentrations of topoisomerase I inhibitors improving survival in vivo in orthotopic patient-derived xenograft neuroblastoma mouse models. CX-5461 recently progressed through phase I clinical trial as a first-in-human inhibitor of RNA-POL I. However, we also use a comprehensive panel of in vitro and in vivo assays to demonstrate that CX-5461 has been mischaracterized and that its primary target at pharmacologically relevant concentrations, is in fact topoisomerase II beta (TOP2B), not RNA-POL I. These findings are important because existing clinically approved chemotherapeutics have well-documented off-target interactions with TOP2B, which have previously been shown to cause both therapy-induced leukemia and cardiotoxicity--often-fatal adverse events, which can emerge several years after treatment. Thus, while we show that combination therapies involving CX-5461 have promising anti-tumor activity in vivo in neuroblastoma, our identification of TOP2B as the primary target of CX-5461 indicates unexpected safety concerns that should be examined in ongoing phase II clinical trials in adult patients before pursuing clinical studies in children.

cancer biology↗

bioRxiv2019

nkx3.2 mutant zebrafish accommodate the jaw joint loss through a phenocopy of the head shapes of Paleozoic agnathans

The vertebrate jaw is a versatile feeding apparatus that facilitated explosive diversification. To function, it requires a joint between the upper and lower jaws, so jaw joint defects - such as osteoarthritis or even ankylosis - are often highly disruptive and difficult to study. To describe consequences of jaw-joint dysfunction, we engineered two independent null alleles of a single jaw-joint marker gene, nkx3.2, in zebrafish. These mutations caused zebrafish to become functionally jawless via fusion of the upper and lower jaw cartilages (ankylosis). Despite lacking jaw joints, nkx3.2 mutants survive to adulthood and accommodate this defect by: a) remodeling their skulls; and b) altering their behavior from suction feeding to ram feeding. As a result of remodeling, nkx3.2 mutants developed superficial similarities to the skull shapes observed in two lineages of ancient jawless vertebrates (anaspids and furcacaudiid thelodonts), including: a fixed open gape, reduced snout, and enlarged branchial region. However, no homology exists in individual skull elements between these taxa, and most of the modified elements in the mutant zebrafish occur outside known expression domains of nkx3.2. Therefore, we interpret the adult nkx3.2 phenotype not as a reversal to an ancestral state, but as convergence due to similar functional requirement of feeding without moveable jaws. This remarkable convergence strongly suggests that jaw movements themselves dramatically influence the development of jawed vertebrate skulls, which implies that functionally viable skull morphologies are finite, with or without functional jaws. Because nkx3.2 null zebrafish display prominent joint ankylosis, drastically modified skull shape, and altered feeding behaviors, these mutants provide a unique model with which to investigate mechanisms of skeletal remodeling and joint diseases.

evolutionary biology↗