Biology subjects

Hedley, A.

Publications and source records attributed to Hedley, A..

11 recordsLinked to original sources

bioRxiv2025

The Androgen Receptor and MYC synergise to modulate the synthesis of Siglec-7 ligands in prostate cancer

Glyco-immune checkpoints have recently been shown to be critical mediators of immunotherapy resistance across multiple cancer types. In clinical trials, immunotherapeutic treatments for prostate cancer have failed to elicit durable clinical responses. PCa progression is driven by transcriptional networks regulated by key transcription factors including the androgen receptor (AR) and the oncogene MYC. How this crossover between hormone and oncogene-driven signalling pathways regulates tumour glyco-immune checkpoints remains unclear. Here, we show that O-glycans are the major substrates for sialylation in prostate cancer and that sialyltransferases that have preferences for O-glycans are differentially regulated by androgens. We show that supraphysiological levels of androgens produce distinct glycopeptide profiles in prostate cancer cells compared with cells exposed to physiological androgens. Additionally, we identify a direct and coordinated role for AR and MYC in regulating ST3Gal1 and the synthesis of Siglec-7 ligands in prostate cancer. Both transcription factors converge to repress ST3GAL1, thereby limiting the generation of Siglec-7 ligands. These findings highlight a context-dependent, cooperative relationship between the AR and MYC in shaping the tumour sialome, linking hormonal signalling and oncogenic transcription to Siglec biology. Our study highlights how cell-type specific differences in transcriptional networks has important downstream effects for immune modulating glycans and has tumour specific clinical implications.

cancer biology↗

bioRxiv2025

Exercise serum promotes DNA damage repair and upregulates DNA repair gene PNKP in colon cancer cells

Exercise protects against colon cancer progression, but the underlying biological mechanisms remain incompletely understood. One proposed mechanism is the release of bioactive molecules into the interstitium and systemic circulation during exercise, which may act directly on precancerous or tumour cells to suppress DNA damage, inhibit proliferation, and preserve genomic stability. Here, we evaluated the effects of exercise-conditioned human serum on DNA damage kinetics and transcriptomic signatures in colon cancer cells. Blood samples were collected from 30 participants (age 50-78 years, body mass index [≥]25 kg/m2) before and immediately after a maximal incremental cycling test. LoVo cells were exposed to pre- or post-exercise serum, treated with 2 Gy irradiation, and assessed for {gamma}-H2AX foci over 24 hours. Compared to pre-exercise serum, post-exercise serum significantly reduced {gamma}-H2AX foci at 6 hours (p=0.024) and decreased the area under the curve (AUC, p=0.014), indicating accelerated DNA repair. Post-exercise serum also increased expression of the DNA repair protein PNKP in LoVo cells, both with and without irradiation (p=0.007 and p=0.029, respectively). Transcriptomic analysis revealed upregulation of mitochondrial energy metabolism and downregulation of cell cycle and proteasome-related pathways. These findings suggest that acute exercise elicits systemic responses that enhance DNA repair and shift colon cancer cells towards a less proliferative transcriptomic state under sublethal genotoxic stress, offering a potential mechanistic explanation for the protective effects of exercise against colorectal carcinogenesis.

cancer biology↗

bioRxiv2023

IL-27 maintains cytotoxic Ly6C+ gamma delta T cells that arise from immature precursors

In mice, {gamma}{delta} T cells that express the co-stimulatory molecule, CD27, are committed to the IFN{gamma}-producing lineage in the thymus, and in the periphery, these cells play a critical role in host defence and anti-tumor immunity. Unlike {beta} T cells that rely on MHC-presented peptides to drive their terminal differentiation, it is unclear whether MHC-unrestricted {gamma}{delta} T cells undergo further functional maturation after exiting the thymus. Here, we provide evidence of phenotypic and functional diversity within peripheral IFN{gamma}-producing {gamma}{delta} T cells. We found that immature CD27+Ly6C-- cells convert into mature CD27+Ly6C+ cells, and these mature cells control cancer progression while the immature cells cannot. The gene signatures of these two subsets were highly analogous to human immature and mature {gamma}{delta} T cells, indicative of conservation across species. We show that IL-27 supports the cytotoxic phenotype and function of mouse CD27+Ly6C+ cells and human V{delta}2+ cells, while IL-27 is dispensable for mouse CD27+Ly6C-- cells and human V{delta}1+ cells. These data reveal increased complexity within IFN{gamma}-producing {gamma}{delta} T cells, comprising of immature and terminally differentiated subsets, that offer new insights into unconventional T cell biology.

immunology↗

bioRxiv2022

CXCR2 inhibition enables NASH-HCC immunotherapy

ObjectiveHepatocellular carcinoma (HCC) is increasingly associated with non-alcoholic steatohepatitis (NASH). HCC immunotherapy offers great promise; however, recent data suggests NASH-HCC may be less sensitive to conventional immune checkpoint inhibition (ICI). We hypothesised that targeting neutrophils using a CXCR2 small molecule inhibitor may sensitise NASH-HCC to ICI therapy. DesignNeutrophil infiltration was characterised in human HCC and mouse models of HCC. Late-stage intervention with anti-PD1 and/or a CXCR2 inhibitor was performed in murine models of NASH-HCC. The tumour immune microenvironment was characterised by imaging mass cytometry, RNA-seq and flow cytometry. ResultsNeutrophils expressing CXCR2, a receptor crucial to neutrophil recruitment in acute-injury, are highly represented in human NASH-HCC. In models of NASH-HCC lacking response to ICI, the combination of a CXCR2 antagonist with anti-PD1 suppressed tumour burden and extended survival. Combination therapy increased intratumoral XCR1+ dendritic cell activation and CD8+ T cell numbers which are associated with anti-tumoral immunity, this was confirmed by loss of therapeutic effect upon genetic impairment of myeloid cell recruitment, neutralisation of the XCR1-ligand XCL1 or depletion of CD8+ T cells. Therapeutic benefit was accompanied by an unexpected increase in tumour-associated neutrophils (TANs) which switched from a pro-tumor to anti-tumour progenitor-like neutrophil phenotype. Reprogrammed TANs were found in direct contact with CD8+ T cells in clusters that were enriched for the cytotoxic anti-tumoural protease granzyme B. Neutrophil reprogramming was not observed in the circulation indicative of the combination therapy selectively influencing TANs. ConclusionCXCR2-inhibition induces reprogramming of the tumour immune microenvironment that promotes ICI in NASH-HCC. Significance of this studyWhat is already known on this subject? O_LIImmune checkpoint inhibition therapy is emerging as a promising new therapy for the treatment of advanced hepatocellular carcinoma (HCC). C_LIO_LIOnly a minority of HCC patients will respond to immune checkpoint inhibition (ICI) therapy and recent data suggest that HCC on the background of NASH may have reduced sensitivity to this treatment strategy. C_LIO_LINeutrophils are a typical myeloid component of the liver in NASH and are found either within the HCC tumour microenvironment or in a peritumoural location. C_LIO_LINeutrophils have considerable phenotypic plasticity and can exist in both tumour promoting and tumour suppressing states. C_LIO_LINeutrophils may have the ability to influence ICI therapy. C_LI What are the new findings? O_LICXCR2+ neutrophils are found in human NASH and within the tumour of both human and mouse models of NASH-HCC. C_LIO_LIThe resistance of NASH-HCC to anti-PD1 therapy is overcome by co-treatment with a CXCR2 small molecule inhibitor, with evidence of reduced tumour burden and extended survival. C_LIO_LIAnti-PD1 and CXCR2 inhibitor combine to selectively reprogramme tumour-associated neutrophils (TANs) from a pro- to an anti-tumour phenotype. C_LIO_LIReprogrammed TANs proliferate locally within Granzyme B+ immune clusters that contain physically associating CD8+ T cells and antigen presenting cells. C_LIO_LIConventional XCR1+ dendritic cells (cDC1s) are found to be elevated in anti-PD1 and CXCR2 inhibitor treated HCCs and together with CD8+ T cells are required for therapeutic benefit. C_LI How might it impact on clinical practice in the foreseeable future? O_LITANs can be selectively manipulated to adopt an anti-tumour phenotype which unlocks their potential for cancer therapy. The ability of CXCR2 antagonism to combine with ICI therapy to bring about enhanced therapeutic benefit in NASH-HCC (and potentially in HCC of other aetiologies) warrents clinical investigation. C_LI

cancer biology↗

bioRxiv2021

Maturation, developmental site, and pathology dictate murine neutrophil function

Neutrophils have been implicated in poor outcomes in cancer and severe inflammation. We found that neutrophils expressing intermediate levels of Ly6G (Ly6GInt) were present in mouse cancer models and more abundant in those with high rates of spontaneous metastasis. Maturation, age, tissue localization and functional capacity all drive neutrophil heterogeneity. Recent studies have proposed various markers to distinguish between these heterogeneous sub-populations; however, these markers are limited to specific models of inflammation and cancer. Here, we identify and define Ly6G expression level as a robust and reliable marker to distinguish neutrophils at different stages of maturation. Ly6GInt neutrophils were bona fide immature neutrophils with reduced immune regulatory and adhesion capacity. Whereas the bone marrow is a more recognised site of granulopoiesis, the spleen also produces neutrophils in homeostasis and cancer. Strikingly, neutrophils matured faster in the spleen than in the bone marrow with unique transcriptional profiles. We propose that developmental origin is critical in neutrophil identity and postulate that neutrophils that develop in the spleen supplement the bone marrow by providing an intermediate more mature reserve before emergency haematopoiesis.

immunology↗

bioRxiv2021

Single-cell analysis uncovers differential regulation of lung γδ T cell subsets by the co-inhibitory molecules, PD-1 and TIM-3

IL-17A-producing {gamma}{delta} T cells within the lung consist of both V{gamma}6+ tissue-resident cells and V{gamma}4+ circulating cells that play important roles in homeostasis, inflammation, infection, tumor progression and metastasis. How these {gamma}{delta} T cell subsets are regulated in the lung environment during homeostasis and cancer remains poorly understood. Using single-cell RNA sequencing and flow cytometry, we show that lung V{gamma}6+ cells express a repertoire of cell surface molecules distinctive from V{gamma}4+ cells, including PD-1 and ICOS. We found that PD-1 functions as a co-inhibitory molecule on V{gamma}6+ cells to reduce IL-17A production, whereas manipulation of ICOS signaling fails to affect IL-17A in V{gamma}6+ cells. In a mammary tumor model, ICOS and PD-1 expression on lung V{gamma}6+ cells remained stable. However, V{gamma}6+ and V{gamma}4+ cells within the lung pre-metastatic niche increased expression of IL-17A, IL-17F, amphiregulin (AREG) and TIM-3 in response to tumor-derived IL-1{beta} and IL-23, where the upregulation of TIM-3 was specific to V{gamma}4+ cells. Inhibition of either PD-1 or TIM-3 in mammary tumor-bearing mice further increased IL-17A by V{gamma}6+ and V{gamma}4+ cells, indicating that both PD-1 and TIM-3 function as negative regulators of IL-17A-producing {gamma}{delta} T cell subsets. Together, these data demonstrate how lung {gamma}{delta} T cell subsets are differentially controlled by co-inhibitory molecules in steady-state and cancer.

immunology↗

bioRxiv2020

Absent expansion of pericentral hepatocytes and altered physiology in Axin2CreERT2 mice

Abstract/IntroductionUnderstanding how the liver regenerates is a key biological question. Hepatocytes are the principle regenerative population in the liver. Recently, numerous lineage tracing studies (which apply genetic tagging to a restricted population and track its descendants over time) have reported conflicting results using a variety of hepatocyte based reporting systems in mice1,2. The first significant lineage tracing from a distinct subpopulation of hepatocytes in homeostasis reported hyper-proliferation of self-renewing pericentral hepatocytes with their subsequent expansion across the liver lobule3. This study used a CreERT2 construct knocked into the endogenous Axin2 locus; here termed Axin2CreERT2. Subsequent studies, using either a different pericentral marker (Lgr54) or a different AxinCreERT2 transgene5, did not show lineage tracing. Here we aim to reconcile these discrepancies by re-evaluating lineage tracing in the Axin2CreERT2 knock-in model and explore the physiological consequences of this mutant allele. We were unable to find evidence of expansion of an Axin2CreERT2 labelled population and show that this population, whilst zonated, is spread throughout the lobule rather than being zonally restricted. Finally, we report that this allele results in profound perturbation of the Wnt pathway and physiology in the mouse.

cell biology↗

bioRxiv2020

Schlafen family member 5 (SLFN5) regulates LAT1-mediated mTOR activation in castration-resistant prostate cancer

Androgen-deprivation therapy (ADT) is the standard of care for the treatment of non-resectable prostate cancer (PCa). Despite high treatment efficiency, most patients ultimately develop lethal castration-resistant prostate cancer (CRPC). In this study, we perform a comparative proteomic analysis of three in vivo, androgen receptor (AR)-driven, orthograft models of CRPC. Differential proteomic analysis reveals that distinct molecular mechanisms, including amino acid (AA) and fatty acid (FA) metabolism, are involved in the response to ADT between the different models. Despite this heterogeneity, we identify SLFN5 as an AR-regulated biomarker in CRPC. SLFN5 expression is high in CRPC tumours and correlates with poor patient outcome. In vivo, SLFN5 depletion strongly impairs tumour growth in castrated condition. Mechanistically, SLFN5 interacts with ATF4 and regulates the expression of LAT1, an essential AA transporter. Consequently, SLFN5 depletion in CRPC cells decreases intracellular levels of essential AA and impairs mTORC1 signalling in a LAT1-dependent manner.

cancer biology↗

bioRxiv2020

Ly6C defines a subset of memory-like CD27+ γδ T cells with inducible cancer-killing function

In mice, IFN{gamma}-producing {gamma}{delta} T cells that express the co-stimulatory molecule, CD27, play a critical role in host defence and anti-tumour immunity. However, their phenotypic diversity, composition in peripheral and secondary lymphoid organs, similarity to {beta} T cells as well as homology with human {gamma}{delta} T cells is poorly understood. Here, using single cell RNA sequencing, we show that CD27+ {gamma}{delta} T cells consist of two major clusters, which are distinguished by expression of Ly6C. We demonstrate that CD27+Ly6C-- {gamma}{delta} T cells exhibit a naive T cell-like phenotype, whereas CD27+Ly6C+ {gamma}{delta} T cells display a memory-like phenotype, produce several NK cell-related and cytotoxic molecules and are highly similar to both mouse CD8+ T cells and mature human {gamma}{delta} T cells. In a breast cancer mouse model, depletion of CD27+ {gamma}{delta} T cells failed to affect tumour growth, but these cells could be coerced into killing cancer cells after expansion ex vivo. These results identify novel subsets of {gamma}{delta} T cells in mice that are comparable to human {gamma}{delta} T cells, opening new opportunities for {gamma}{delta} T cell-based cancer immunotherapy research.

immunology↗

bioRxiv2020

Metabolic control of tumour extracellular matrix production in cancer-associated fibroblasts

TElevated production of collagen-rich extracellular matrix (ECM) is a hallmark of cancer associated fibroblasts (CAFs) and a central driver of cancer aggressiveness. How to target ECM production to oppose cancer is yet unclear, since targeting CAFs has been shown to restrain but also promote cancer progression. Metabolic rewiring is a hallmark of CAFs. Here we find that proline, which is a highly abundant amino acid in collagen proteins, is newly synthesised from glutamine to make tumour collagen in breast cancer xenografts, and that its production is elevated in breast cancer CAFs. PYCR1 is the rate-limiting enzyme for proline synthesis and is highly expressed in the tumour stroma of breast cancer patients and in CAFs. Reducing PYCR1 levels in CAFs is sufficient to reduce tumour collagen production, tumour growth and metastatic spread in vivo and cancer cell proliferation in vitro. PYCR1 and COL1A1 are overexpressed in patients with invasive ductal carcinoma with poor prognosis. Both collagen and glutamine-derived proline synthesis in CAFs are enhanced by increased pyruvate dehydrogenase-derived acetyl-CoA levels, via gene expression regulation through the epigenetic regulator histone acetyl transferase EP300. Altogether, our work unveils unprecedented roles of CAF metabolism to support pro-tumorigenic collagen production. PYCR1 is a recognised cancer cell vulnerability and potential target for therapy, hence, our work provides evidence that targeting PYCR1 in tumours may have the additional benefit of halting the production of pro-tumorigenic ECM.

cancer biology↗

bioRxiv2018

The ERBB network facilitates KRAS-driven lung tumorigenesis

KRAS is the most frequently mutated driver oncogene in human adenocarcinoma of the lung. There are presently no clinically proven strategies for treatment of KRAS-driven lung cancer. Activating mutations in KRAS are thought to confer independence from upstream signaling, however recent data suggest that this independence may not be absolute. Here we show that initiation and progression of KRAS-driven lung tumors requires input from ERBB family RTKs: Multiple ERBB RTKs are expressed and active from the earliest stages of KRAS driven lung tumor development, and treatment with a multi-ERBB inhibitor suppresses formation of KRasG12D-driven lung tumors. We present evidence that ERBB activity amplifies signaling through the core RAS pathway, supporting proliferation of KRAS mutant tumor cells in culture and progression to invasive disease in vivo. Importantly, brief pharmacological inhibition of the ERBB network significantly enhances the therapeutic benefit of MEK inhibition in an autochthonous tumor setting. Our data suggest that lung cancer patients with KRAS-driven disease may benefit from inclusion of multi-ERBB inhibitors in rationally designed treatment strategies.\n\nOne Sentence SummaryG12 Mutant KRAS requires tonic ERBB network activity for initiation and maintenance of lung cancer

cancer biology↗