Biology subjects

Lock, J. G.

Publications and source records attributed to Lock, J. G..

9 recordsLinked to original sources

bioRxiv2025

Deep multiplexed 50-marker imaging of circulating tumor cells expands actionable biomarker profiling for precision oncology

Liquid biopsy-derived circulating tumor cells (CTCs) offer a minimally invasive avenue for precision oncology by enabling longitudinal monitoring of actionable molecular and cell-phenotypic biomarkers. However, conventional immunofluorescence imaging-based CTC profiling captures just 4-5 markers per cell, restricting crucial insights into oncogenic and resistance drivers, as well as tumor cell heterogeneity. Here we present an integrated pipeline employing deep multiplexed imaging to profile up to 50 molecular markers per CTC, capturing expression, phosphorylation, and subcellular localization of diverse biomarkers. Validated in a multi-stage prostate cancer resistance model and applied to prostate cancer patient-derived CTCs, this approach enhances CTC classification and reveals inter- and intra-patient heterogeneity correlating with therapy response. Machine learning identified therapeutically actionable signatures, suggesting patient-specific treatment strategies. This deep multiplexed imaging pipeline advances the utility of CTCs in guiding personalized cancer therapy by providing comprehensive molecular and phenotypic insights through minimally invasive liquid biopsies. Highlights- Multiplexed immunofluorescence imaging of circulating tumor cells captures up to 50 molecular markers per cell with subcellular localisation. - Single-cell and subcellular analyses identify quantitative signatures correlating with patient outcome, as well as therapeutically actionable biomarkers. - This method transforms the utility of CTCs for future use in patient stratification and for guiding personalised therapies. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=181 SRC="FIGDIR/small/684075v1_ufig1.gif" ALT="Figure 1"> View larger version (47K): org.highwire.dtl.DTLVardef@a36ff4org.highwire.dtl.DTLVardef@b06c1org.highwire.dtl.DTLVardef@1e8a572org.highwire.dtl.DTLVardef@c60753_HPS_FORMAT_FIGEXP M_FIG Graphical Abstract C_FIG

cancer biology↗

bioRxiv2025

Generative semantic multiplexing (SemaPlex) for accessible and scalable multiplexed fluorescence imaging

Multiplexed fluorescence imaging enhances spatially-resolved interrogation of complex, multi-molecular cell processes that are insufficiently sampled using standard 4-5 plex imaging. To improve accessibility and scalability for multiplexed imaging, we demonstrate generative Semantic Multiplexing (SemaPlex); a simple experimental and deep learning strategy for amplifying marker plexity several-fold by semantically unmixing multiple markers combined per imaging channel. We first characterise key determinants of SemaPlex performance, achieving precise computational multiplexing of 2-to-8 markers synthetically mixed in one channel, facilitating enhanced cell phenotype classification. We then demonstrate practical SemaPlex application, acquiring 10 markers over 4 channels (3*3-plex+1) to efficiently emulate real multiplexed labelling. This permitted accurate reconstruction of quantitative single-cell phenotypic manifolds delineating cell-cycle and mitotic dynamics, with internally validated error-detection. Finally, we exemplify use of semantic guides; additional input channels that significantly enhance multiplexing fidelity. SemaPlex makes multiple-fold increases in fluorescence imaging-plexity accessible, scalable and customisable; democratising multiplexed imaging-based interrogation of complex cell biology.

systems biology↗

bioRxiv2025

Image quality metrics fail to accurately represent biological information in fluorescence microscopy

Image processing methods offer the potential to improve the quality of fluorescence microscopy data, allowing for image acquisition at lower, less phototoxic illumination doses. The training and evaluation of such methods is informed and driven by full-reference image quality metrics (IQMs); however, these metrics derive from applications to natural scene images, not fluorescence microscopy images. Here we investigate the response of IQMs to common properties of fluorescence microscopy data and whether IQMs are capable of reporting the biological information content of images. We find that IQM scores are biased by image content for both raw and processed microscopy data, and that improvements in IQM values reported after processing are not reliably correlated with performance in downstream analysis tasks. As common IQMs are unreliable proxies for guiding image processing developments in biological fluorescence microscopy, image processing performance should be benchmarked according to downstream analysis success.

bioinformatics↗

bioRxiv2025

Capillary constrictions prime cancer cell tumorigenicity through PIEZO1

Metastasis is a hallmark of cancer and is responsible for the majority of cancer-related deaths. Evidence suggests that even a single cancer cell can spread and seed a secondary tumour. However, not all circulating tumour cells have this ability, which implies that dissemination and distal growth require adaptative mechanisms during circulation. Here we report that constriction during microcapillary transit will trigger reprogramming of melanoma cells to a tumorigenic cancer stem cell-like state. Using a microfluidic device mimicking physiological flow rates and gradual capillary narrowing, we showed that compression through narrow channels lead to cell and nuclear deformation, rapid changes in chromatin state and increased calcium handling through the mechanosensor PIEZO1. Within minutes of microcapillary transit, cells show increased regulation of transcripts associated with metabolic reprogramming and metastatic processes, which culminates in the adoption of cancer stem cell-like properties. Squeezed cells displayed elevated melanoma stem cell markers, increased propensity for trans-endothelium invasion, and characteristics of enhanced tumorigenicity in vitro and in vivo. Pharmacological disruption of channel activity inhibited the stem cell-like state, while the selective PIEZO1 activator Yoda1 primed this state irrespective of constriction. Finally, deletion of PIEZO1 led to complete abrogation of the constriction-induced stem cell-like state. Together, this work demonstrates that compressive forces during circulation can reprogram circulating cancer cells to tumorigenic stem cell-like states that are primed for extravasation and metastatic colonization.

cancer biology↗

bioRxiv2025

Gene-Corrected Basal Cells Restore CFTR In Vitro; Transplants Regenerate Epithelium in a Preclinical Sinus Model

BackgroundCystic fibrosis (CF) is caused by mutations in the CFTR gene, leading to epithelial dysfunction and progressive lung disease. Although CFTR modulators have transformed care, [~]10% of people with CF remain without effective therapy. Durable, mutation-agnostic approaches are urgently needed. MethodWe used a lentiviral (LV) vector to deliver wild-type CFTR to airway basal cells derived from 13 paediatric CF participants with a range of genotypes. Transduced cells were assessed for transgene expression, epithelial differentiation, and CFTR function using air-liquid interface (ALI) cultures. Separately, to evaluate regenerative capacity in vivo, LVGFP-transduced rabbit airway basal cells were transplanted into the denuded nasal septum of healthy New Zealand white rabbits using a biocompatible scaffold. ResultsTransduced basal cells retained multilineage differentiation capacity, forming well-organized, pseudostratified epithelium with intact barrier function and ciliary activity. CFTR channel activity was restored to levels comparable to or exceeding those achieved with elexacaftor/tezacaftor/ivacaftor (ETI), including in individuals with nonsense mutations. Combined CFTR transduction plus ETI treatment showed additive benefit. In vivo, transplanted rabbit basal cells engrafted and differentiated to regenerate a mucociliary epithelium, with improved nasal potential difference and mucociliary clearance compared to scaffold-only controls. ConclusionOur study demonstrates that LV-mediated CFTR gene addition restores CFTR function in vitro across genotypes and supports epithelial regeneration in a clinically relevant animal airway model. This two-part platform offers a scalable path toward cell therapies for all people with CF and may have broader applications in upper airway epithelial repair.

cell biology↗

bioRxiv2025

Epithelial-mesenchymal cell state heterogeneity predetermines differential phospho-signaling responses to epidermal growth factor stimulation

Understanding why isogenic cancer cells respond differently to equivalent oncogenic stimuli is vital for optimizing anticancer therapies. Emerging evidence suggests that pre-existing differences in cell state may modulate signaling responses to new stimuli, but the interplay of specific cell states and signals remains unclear. We investigated whether epithelial-mesenchymal (E/M) state, a major axis of cancer cell heterogeneity, influences signaling responses to epidermal growth factor (EGF), a critical oncogenic stimulus in non-small cell lung cancer (NSCLC). We imaged >64,000 A549 NSCLC cells labeled for DNA, F-actin and alternate signaling markers (p-AKT-S473, p-AKT-T308, p-ERK or p-S6) after acute stimulation. Quantitative single-cell morphological and spatial profiling defined a stimulus-invariant E/M state landscape over which EGF signaling responses were compared. This revealed state-dependent differences in signal-activation magnitudes, dynamics and subcellular routing. AKT responses exhibited phosphosite- and compartment-specific dynamics across states, with epithelial cells showing strong, transient membrane-localized S473 and higher internalized T308, whereas mesenchymal cells displayed weaker but sustained nuclear and ruffle-localized S473. Regression-based computational multiplexing concurrently inferred all signaling responses per cell, mapping state-dependent divergence in multi-molecular signaling trajectories. E/M state thus pre-determines distinctive spatiotemporal profiles of EGF-induced signaling, with implications for signaling functions and anti-signaling therapy responses across E/M state-diverse tumors.

cancer biology↗

bioRxiv2023

Learning transcriptional and regulatory dynamics driving cancer cell plasticity using neural ODE-based optimal transport

While single-cell technologies provide snapshots of tumor states, building continuous trajectories and uncovering causative gene regulatory networks remains a significant challenge. We present Cflows, an AI framework that combines neural ODE networks with Granger causality to infer continuous cell state transitions and gene regulatory interactions from static scRNA-seq data. In a new 5-time point dataset capturing tumorsphere development over 30 days, Cflows reconstructs two types of trajectories leading to tumorsphere formation or apoptosis. Trajectory-based cell-of-origin analysis delineated a novel cancer stem cell profile characterized by CD44hiEPCAM+CAV1+, and uncovered a cell cycle-dependent enrichment of tumorsphere-initiating potential in G2/M or S-phase cells. Cflows uncovers ESRRA as a crucial causal driver of the tumor-forming gene regulatory network. Indeed, ESRRA inhibition significantly reduces tumor growth and metastasis in vivo. Cflows offers a powerful framework for uncovering cellular transitions and dynamic regulatory networks from static single-cell data.

cancer biology↗

bioRxiv2022

Copper chelation inhibits TGF-β pathways and suppresses epithelial-mesenchymal transition in cancer

Copper is a trace element essential to cellular function with elevated levels implicated in cancer progression. Clinical trials using copper chelators are associated with improved patient survival, however, the molecular mechanisms by which copper depletion inhibits tumor progression are poorly understood. This remains a major hurdle to the clinical translation of copper chelators. Epithelial-mesenchymal transition (EMT) is often exploited by malignant cells to promote growth and metastasis. Transforming growth factor (TGF)-{beta} is a master regulator of EMT and facilitates cancer progression through changes in the tumor and its microenvironment. Herein, we report that a reduction of copper with the chelating agent tetraethylenepentamine (TEPA) inhibited EMT in vitro in three diverse cancer cell types; human triple-negative breast cancer (TNBC), neuroblastoma (NB), and diffuse intrinsic pontine glioma (DIPG) cell lines. Single-molecule imaging demonstrated EMT markers including Vimentin, {beta}-catenin, ZEB1, and p-SMAD2 had increased expression with copper treatment and this pro-mesenchymal shift was rescued by the addition of TEPA. Moreover, SNAI1, ZEB1, and p-SMAD2 demonstrated increased accumulation in the cytoplasm after treating with TEPA. Transcriptomic analyses revealed a significant downregulation of the EMT pathway, including canonical (TGF-{beta}/SMAD2&3) and non-canonical (TGF-{beta}/PI3K/AKT and TGF-{beta}/RAS/RAF/MEK/ERK) TGF signaling pathways. Matrix metalloproteinases MMP-9 and MMP-14 proteins which activate latent TGF-{beta} complexes were also downregulated by TEPA treatment. These molecular changes are consistent with reduced plasma levels of TGF-{beta} we observed in cancer models treated with TEPA. Importantly, copper chelation reduced metastasis to the lung in a TNBC orthotopic syngeneic mouse model. Our studies suggest copper chelation therapy can be used to inhibit EMT-induced metastasis by targeting TGF-{beta} signalling. Because on-target anti-TGF-{beta} therapies are failing in the clinic, copper chelation presents itself as a potential therapy for targeting TGF-{beta} in cancer.

cancer biology↗

bioRxiv2017

Reticular adhesions: A new class of adhesion complex that mediates cell-matrix attachment during mitosis

Adhesion to the extracellular matrix (ECM) persists during mitosis in most cell types. Yet, classical adhesion complexes (ACs), such as focal adhesions and focal complexes, do and must disassemble to enable cytoskeletal rearrangements associated with mitotic rounding. Given this paradox, mechanisms of mitotic cell-ECM adhesion remain undefined. Here, we identify reticular adhesions, a new class of AC that is mediated by integrin v{beta}5, formed during interphase and preserved at cell-ECM attachment sites throughout cell division. Consistent with this role, integrin {beta}5 depletion perturbs mitosis and disrupts spatial memory transmission between cell generations. Quantitative imaging reveals reticular adhesions to be both morphologically and dynamically distinct from classic focal adhesions, while mass spectrometry defines their unique composition; lacking virtually all consensus adhesome components. Indeed, remarkably, reticular adhesions are functionally independent of both talin and F-actin, yet are promoted by phosphatidylinositol-4,5-bisphosphate (PI-4,5-P2). Overall, the distinct characteristics of reticular adhesions provide a unique solution to the problem of maintaining cell-ECM attachment during mitotic rounding and division.

cell biology↗