Biology subjects

Cook, L. M.

Publications and source records attributed to Cook, L. M..

6 recordsLinked to original sources

bioRxiv2026

Joint effects of climate change and urbanization accelerate plant biodiversity loss across urban green spaces

Urbanization and climate change are rapidly reshaping biodiversity worldwide, yet their combined impacts on ecosystems remain poorly understood. Urban green spaces (UGS) underpin urban biodiversity, but differ widely in their structure, management, and exposure to global change. Here, we examine how these two drivers jointly influence plant communities across five major UGS types (allotments, private gardens, residential green spaces, parks, and ruderal areas) in three socio-culturally distinct Swiss cities. By combining vegetation surveys from 180 sites (60 sites per city) with species-specific thermal niches, high-resolution projections of historical and future urban microclimates, and land-use change scenarios, we trace how climate-driven species loss interacts with the shifting availability of urban habitats to shape biodiversity outcomes by mid-century. We found that UGS types differed markedly in their contributions to biodiversity, with allotments and ruderal areas supporting disproportionately high compositional uniqueness. However, climate change alone was projected to drive substantial plant diversity declines across all UGS types, with 40-80% of species exceeding their thermal niches by mid-century based on climate change scenario and UGS type. Although allotments exhibited relatively greater tolerance due to broader community-level thermal preferences, this advantage was undermined by their rapid decline under urbanization. When considered jointly, climate change and urbanization generated widespread biodiversity losses through complementary mechanisms: climate change drove species declines, while urbanization amplified these losses by disproportionately reducing high-value habitats. These results reveal a consistent trajectory of biodiversity decline across urban landscapes and highlight the need to conserve high-diversity yet shrinking UGS, particularly allotments, while enhancing the ecological value and climate resilience of expanding UGS, such as parks and residential areas, to safeguard future urban biodiversity under global change.

ecology↗

bioRxiv2026

An Immunocompetent Mouse Model of Degarelix Induced Chemical Castration to Investigate Acquired Resistance to Androgen Deprivation.

Prostate cancer (PC) remains a significant health concern as the second leading cause of cancer-related death in American men. Androgen deprivation therapies represent the standard of care for patients with PC, regardless of disease stage. Gonadotropin-releasing hormone (GnRH) antagonists, such as Degarelix, are commonly used hormone therapies for PC and work by suppressing testosterone production. Previous studies indicate a prostate involution-regeneration cycle following surgical castration and testosterone addback. However, whether a similar response occurs following pharmacologic androgen deprivation with agents such as Degarelix remains poorly understood. In particular, the temporal dynamics of prostate involution and subsequent regeneration after chemical castration have not been systematically defined. Our study utilizes immunocompetent mouse models to evaluate the systemic and temporal effects of Degarelix treatment and determine its efficacy in suppressing PC tumor growth. We show that continuous Degarelix treatment significantly suppressed systemic testosterone levels in mice, whereas testosterone levels returned to physiological baseline following Degarelix withdrawal. Gross anatomical, H&E, and Trichrome analyses demonstrated that Degarelix induced castration resulted in prostate involution, characterized by reduced gland size and increased stromal remodeling. This phenotype was reversed after Degarelix withdrawal, highlighting the reversibility of pharmacological androgen deprivation. Immunofluorescence staining revealed changes in basal and luminal epithelial cell populations within the prostatic gland, indicating changes in prostate glandular architecture following Degarelix induced castration and subsequent regeneration. Next, we evaluated the impact of chemical castration on PC tumor growth. Although Degarelix initially suppressed tumor growth, this response was not sustained through the study endpoint, suggesting the emergence of acquired resistance to androgen deprivation. These findings establish this immunocompetent model as a physiologically relevant platform for dissecting the mechanisms that drive therapeutic resistance and tumor progression following androgen deprivation. Our findings highlight the effectiveness of chemical castration with Degarelix and establish a robust model to study both therapeutic responses and the emergence of castration resistance in PC.

cancer biology↗

bioRxiv2026

An Integrated Preclinical Platform for Lethal Neuroendocrine Prostate Cancer from Rapid Autopsy Bone and Liver Metastases.

Treatment-emergent neuroendocrine prostate cancer (NEPC) is an aggressive, therapy-resistant disease arising in up to 20% of castration resistant prostate cancers, yet robust biologically relevant preclinical models remain scarce. Here, we describe a technical blueprint for establishing an integrated platform of patient-derived models from visceral and bone metastases collected through a prostate cancer rapid autopsy program (PC RAP). We report the establishment and characterization of patient-derived xenograft (PDX) models from liver metastasis tissue, liver and bone metastasis-derived organoid lines (PDOs), and corresponding patient-derived organoid xenograft (PDOX) models. In addition, we established, to our knowledge, the first mesenchymal stem cell (MSC) cultures derived from neuroendocrine prostate cancer (NEPC) bone metastases. The PDOs preserved intratumoral heterogeneity, displaying both CRPC-NE and CRPC-adenocarcinoma features. These organoids retained neuroendocrine identity across multiple passages, with transcriptomic profiles concordant with the original patient tissue and matched PDX models generated at our institution and at the National Cancer Institute (NCI Patient-Derived Models Repository). To model the bone metastatic microenvironment, we generated novel organoid-based New Approach Methodologies (NAMs) by co-culturing PDOs with iPSC-derived bone marrow organoids, establishing a physiologically relevant vascularized organotypic model of PC bone metastasis. To extend our studies in vivo, we established preclinical models using the liver and bone metastasis-derived organoid models. The PDOX models were tumorigenic and developed spontaneous lymph node metastases, providing clinically relevant models for investigating lethal NEPC biology. Together, these complementary patient-derived models provide a robust and versatile platform for investigating NEPC biology, metastatic progression, and evaluating new therapeutic strategies. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=184 SRC="FIGDIR/small/740121v1_ufig1.gif" ALT="Figure 1"> View larger version (57K): org.highwire.dtl.DTLVardef@1c641f1org.highwire.dtl.DTLVardef@113696aorg.highwire.dtl.DTLVardef@16dcc72org.highwire.dtl.DTLVardef@1898d9f_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsO_LINovel preclinical models of visceral and bone metastases established from a prostate cancer rapid autopsy program. C_LIO_LIThis study is the first to establish mesenchymal stem cell cultures from NEPC bone metastases. C_LIO_LIPDOs preserve heterogeneity, showing both CRPC-NE and CRPC-Adeno features, with transcriptomic profiles concordant with originator tissue and PDX models. C_LIO_LIPC RAP-derived organoids are tumorigenic in vivo and generate spontaneous lymph node metastases. C_LI

cancer biology↗

bioRxiv2026

Small habitat patches can be the largest contributors to urban biodiversity across taxonomic groups

AimAs cities densify and expand, the careful planning and design of green spaces are essential for supporting urban biodiversity. Here, we evaluate the relative contribution of habitat patches of varying size, quality, and connectivity to urban biodiversity and assess environmental factors driving differences in species richness and community composition. LocationZurich, Switzerland. Time period: 2008-2018.Major taxa studied: Invertebrates, vertebrates, and trees. MethodsWe analyzed species occupancy data from 452 habitat patches. We quantified alpha, beta, and gamma diversity, assessed species-area relationships, and applied generalized dissimilarity modelling to test the role of patch area, connectivity, and habitat quality--proxied through environmental variables, including vegetation complexity, water presence, and forest isolation--in shaping community composition. ResultsAlpha diversity increased significantly with area, although small patches (usually < 5 ha) disproportionately contributed to beta diversity. Per unit area, groups of small patches yielded higher gamma diversity than equivalent areas of large patches, particularly for trees and invertebrates. Community composition was strongly influenced by patch area, with effects mediated by vegetation complexity, water, and isolation, with responses differing among taxa. Main conclusionsSmall habitat patches play a critical role in enhancing overall urban biodiversity. They increase species richness through cumulative area effects and promote community turnover (mediated by environmental heterogeneity). Maintaining networks of small patches alongside large green spaces is therefore key to conserving biodiversity in urban landscapes.

ecology↗

bioRxiv2023

Role of GD2 and its biosynthetic enzyme GD3 synthase in prostate cancer tumorigenesis

While better management of loco-regional prostate cancer (PC) has greatly improved survival, advanced PC remains a major cause of cancer deaths. Identification of novel targetable pathways that contribute to tumor progression in PC could open new therapeutic options. The di-ganglioside GD2 is a target of FDA-approved antibody therapies in neuroblastoma, but the role of GD2 in PC is unexplored. Here, we show that GD2 is expressed in a small subpopulation of PC cells in a subset of patients and a higher proportion of metastatic tumors. Variable levels of cell surface GD2 expression were seen on many PC cell lines, and the expression was highly upregulated by experimental induction of lineage progression or enzalutamide resistance in CRPC cell models. GD2high cell fraction was enriched upon growth of PC cells as tumorspheres and GD2high fraction was enriched in tumorsphere-forming ability. CRISPR-Cas9 knockout (KO) of the rate-limiting GD2 biosynthetic enzyme GD3 Synthase (GD3S) in GD2high CRPC cell models markedly impaired the in vitro oncogenic traits and growth as bone-implanted xenograft tumors and reduced the cancer stem cell (CSC) and epithelial-mesenchymal transition (EMT) marker expression. Our results support the potential role of GD3S and its product GD2 in promoting PC tumorigenesis by maintaining cancer stem cells and suggest the potential for GD2 targeting in advanced PC.

cancer biology↗

bioRxiv2022

Androgen-mediated TGFβ expression suppresses anti-tumor neutrophil response in bone metastatic prostate cancer

Prostate Cancer (PCa) bone metastases are associated with spinal cord compression, fracture, bone pain and death. Despite advances in the medical therapy for localized disease, metastatic disease is incurable and osseous progression is largely dictated by tumor-stromal interactions in the bone microenvironment. We showed previously that tumor bone neutrophils are tumoricidal to PCa but lose their cytotoxic potential as the tumor progresses. However, there have been no studies to date to clinically define and characterize neutrophils throughout the prostate cancer disease spectrum to determine their biomarker potential. Using patient peripheral blood polymorphonuclear neutrophils (PMNs), we identify that PCa progression dictates PMN properties, including viability, cell surface markers and gene expression. However, the majority of PMNs elicited an anti-tumor response ex vivo demonstrating that PMN cytotoxicity is cell autonomous and independent of PCa disease stage. In fact, we identify a novel role for androgen regulation, i.e., androgen deprivation therapy (ADT), in suppressing PMN cytotoxicity via altered transforming growth factor beta receptor I (T{beta}RI). Using preclinical models, we found that high dose testosterone/bipolar androgen therapy (BAT) and genetic or pharmacologic T{beta}RI inhibition combined with standard ADT rescued the androgen-associated suppression and restored PMN anti-tumor immune response. This combination provided a therapeutic strategy more impactful than ADT alone, in bone metastatic prostate cancer (BM-PCa). These studies: 1) highlight a necessity for both molecular and functional characterization of PMNs per cancer type and 2) reveals the ability to program PMN immune response for successful targeting of BM-PCa.

cancer biology↗