Biology subjects

Chen, Z.

Publications and source records attributed to Chen, Z..

At least 163 records · Page 9Linked to original sources

bioRxiv2026

Harnessing Tumor-Specific Transcript Diversity Uncovers a Shared Neoantigen Reservoir for Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is refractory to immunotherapy due to its immunologically cold microenvironment and the scarcity of mutation-derived neoantigens. Here, we introduce NeoAPP, a computational tool designed to systematically decode neoantigens arising from tumor-specific transcripts (TSTs) generated by transcriptional dysregulation. Multi-cohort transcriptomic profiling of 413 PDAC samples using NeoAPP reveal a median of 351 neoantigens per sample derived from 56 neoantigen-encoding TSTs (neoTSTs), surpassing mutation-derived counterparts in both abundance and patient coverage. Mechanistic analyses show that non-canonical splicing junction and transposable element activation drive neoantigen generation, while FOXA2-regulated promoter usage constitutes a potential major source of neoTSTs. Tumor-derived neoTSTs are also detected in extracellular vesicles and cancer-associated fibroblasts, implicating stromal crosstalk in immune modulation. Vaccination with neoTSTs induce CD8+ T cell responses in HLA-A*02:01/A*11:01 transgenic mice and suppressed tumor growth in syngeneic PDAC models. Collectively, this work establishes TST-derived neoantigens as a dominant and therapeutically actionable antigen reservoir in PDAC, advancing a transcriptome-guided framework for neoantigen discovery with potential to overcome immune resistance in low-mutation cancers. Abstract Figure O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=196 SRC="FIGDIR/small/705024v1_ufig1.gif" ALT="Figure 1"> View larger version (71K): org.highwire.dtl.DTLVardef@82ff31org.highwire.dtl.DTLVardef@401342org.highwire.dtl.DTLVardef@b0771corg.highwire.dtl.DTLVardef@15c03ef_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

bioRxiv2026

SGLT2 Inhibitors Rescue Lysosomal mTORC1 Hyperactivity and Proximal Tubulopathy in Preclinical Models of Cystinosis

The loss of lysosomal cystine transporter cystinosin (CTNS) disrupts kidney proximal tubule (PT) function, causing cystinosis - a prototypical lysosomal storage disorder characterized by cystine accumulation and metabolic dyshomeostasis. Cystine storage disrupts lysosomal nutrient sensing and downstream mTORC1 signalling, driving loss of PT differentiation and proximal tubulopathy. Here, using cross-species disease models, differentiated cellular systems, lysosome-based assays, and transcriptomics profiling, we demonstrate that sodium-glucose co-transporter 2 (SGLT2) inhibitors (empagliflozin or dapagliflozin) ameliorate proximal tubulopathy in cystinosis. In CTNS-deficient PT cells, SGLT2 inhibition restores lysosome proteolysis, autophagic flux, metabolic homeostasis, and epithelial differentiation and function, independently of cystine clearance. Mechanistically, SGLT2 inhibition reduces the assembly of the v-ATPase-Ragulator-Rag scaffolding complex at lysosomes, thereby decoupling cystine storage from pathological mTORC1 activation. These effects reprogram PT metabolic trajectories and differentiation states, mitigating proximal tubulopathy across zebrafish and rodent models of cystinosis. Together, these findings define a lysosome-metabolism crosstalk that links glucose handling to mTORC1 regulation and provide a rationale for repurposing SGLT2 inhibitors as a disease-modifying therapy for cystinosis and related lysosome-driven PT disorders.

pathology↗

bioRxiv2026

Functional and Structural Basis of Omicron BA.3.2.1 Spike

SARS-CoV-2 Omicron descendant BA.3.2, derived from BA.3 and carrying 39 additional spike substitutions, prompts concerns about altered fitness and antigenicity. Using BA.3.2.1 as a representative sublineage, we have engineered live-attenuated mNeonGreen SARS-CoV-2 encoding spikes from BA.3.2.1 and the JN.1-derived LP.8.1 and XEC, and benchmarked them against BA.3 and KP.3 in Calu-3 cells and primary human airway epithelium. BA.3.2.1 outcompetes BA.3 yet replicates more slowly than JN.1-descendants. Despite increased RBD-hACE2 affinity, BA.3.2.1 spike binds hACE2 less efficiently than LP.8.1, and shows the greatest resistance to neutralization by sera from KP.2/KP.3 infections. Cryo-EM reveals a predominantly closed, compact, asymmetric trimeric spike with a remodeled N-terminal domain, a distinct fusion-peptide-proximal region and altered N-glycosylation. BA.3.2.1 spike adopts a fine-tuned receptor-binding interface and shifted monoclonal-antibody footprints. These findings identify a trade-off between immune evasion and replication fitness driven by closed spike conformation, rationalizing BA.3.2s limited prevalence and underscoring the necessity for continued variant surveillance.

microbiology↗

bioRxiv2026

Macrophage Antigen Presentation Is Unleashed by Pan-RAS Inhibition to Promote Antitumor Immunity

Pan-RAS inhibitors have emerged as potent targeted therapies designed to suppress oncogenic signaling in RAS-mutant tumors. However, whether these inhibitors possess therapeutic utility beyond tumors with intrinsic RAS dependency remains unclear. Here we show that the clinical-stage pan-RAS(ON) inhibitor RMC-6236 (Daraxonrasib) induces robust regression of NRAS-wild-type B16 tumors in immunocompetent mice, a response mediated by a mechanism independent of direct tumor-cell targeting. Instead, RMC-6236 acts by remodeling the tumor microenvironment, specifically enhancing the antigen-presenting capacity of tumor-associated macrophages through upregulated MHC-I expression. This anti-tumor efficacy is abrogated in T cell-deficient hosts, identifying a macrophage-dependent, T cell-mediated mechanism of control. Mechanistically, RMC-6236 does not directly block canonical RAS signaling in macrophages. Rather, it suppresses a Myc-Hdac2 epigenetic program, leading to enhanced histone H4 acetylation at the Nlrc5 locus and subsequent activation of the MHC-I master regulator NLRC5. Together, our findings reveal a macrophage-centered, epigenetically wired immune mechanism for pan-RAS inhibition that broadens the therapeutic scope of targeting the "undruggable" RAS pathway beyond tumor genotype towards systemic immune modulation.

immunology↗

bioRxiv2026

Engineering physically optimized T cells for increased sampling of complex tumor microenvironments

Pancreatic ductal adenocarcinoma (PDA) remains highly lethal, in part, because its dense fibroinflammatory stroma restricts therapy distribution, including adoptive T cell immunotherapies where direct interactions between T and carcinoma cells are essential for effective therapy. While T cell function must be maintained once effector-target engagement occurs, without inducing co-localization subsequent cytotoxic function steps cannot be undertaken. We therefore developed a strategy to "physically optimize" T cells to more effectively sample complex tumor volumes. Informed by pharmacologic perturbations and mathematical modeling we shifted T cell phenotype through expression of constitutively activated RhoA to increase cortical contractility, activation, migration, and sampling in PDA, while showing decreases in exhaustion markers. In CAR T cells this results in more efficient targeting through decreased sampling time and increased engagement with carcinoma cells, consistent with modeling predictions. This significantly increases T cell infiltration and distribution in PDA, resulting in improved tumor control in vivo, suggesting that this is an effective strategy to overcome stromal constraints, improve tumor engagement, and enhance the therapeutic performance of engineered T cell therapies in solid tumors.

bioengineering↗

bioRxiv2026

DISCO-LAMP: A Novel discontinuous LAMP assay for isothermal antigen detection

Proximity ligation assay (PLA), in which the ligation of two DNA probes is greatly accelerated by the associating target molecules, has emerged as a highly sensitive technique for protein detection. The detection of the ligated DNA typically relies on PCR, which requires temperature cycling. In this study, we report on a novel discontinuous (DISCO)-LAMP assay that enables the wash-free detection of PLA products via loop-mediated isothermal amplification (LAMP). Due to the exponential amplification nature of LAMP, a careful balance between efficient amplification of the ligated full-length DNA and minimal background amplification from the individual constituent probes is essential but often challenging to achieve. After extensive template/primer design and assay optimization, DISCO-LAMP assay achieved a detection limit of 1 fM for the ligated DNA probe while maintaining undetectable background amplification at 1 nM of each individual probe. DISCO-LAMP detected Shiga toxin 2 (Stx2) with a limit of detection (LoD) of 100 fM when functionalized with Stx2-binders, as well as both Wuhan-1 and Omicron spike protein when functionalized with DS16, a newly engineered DARPin targeting a conserved epitope on the SARS-CoV-2 Spike protein. We believe DISCO-LAMP represents a versatile and efficient LAMP-based PLA technology that is readily adaptable for sensing diverse targets.

bioengineering↗

bioRxiv2026

Mechanistic Language Modeling and Oxygenated 3D Screening Reveal Berberine and Enzalutamide Synergy in Resistant Prostate Cancer

Resistance to androgen receptor inhibitors remains a primary challenge in prostate cancer treatment, yet identifying synergis-tic co-therapies is hindered by immense combinatorial search spaces and the limited interpretability of predictive computation models. Here, we developed an integrated discovery-validation axis coupling knowledge-augmented large language models with oxygen-supplemented 3D spheroid assays. By leveraging inherent model stochasticity, our framework measures the degree of consensus across independent predictions to establish a formal metric for predictive accuracy. This principle enables high-throughput assessment of complex signaling crosstalk, yielding mechanistic rationales for all predictions and defining a high-confidence zone that minimizes experimental attrition. Utilizing this approach to screen 3,592 natural products, we identified a previously unrecognized synergy between berberine and enzalutamide that re-sensitizes resistant cells. Validation confirms that berberine perturbs the PI3K/AKT/mTOR and AMPK axes, a finding consistent with the mechanistic rationales computationally derived by the framework. Integrating interpretable AI with physiologically relevant 3D screening provides a scalable methodology for the rational discovery of synergistic therapies. SignificanceIntegrating mechanistic AI with oxygenated 3D screening, we identify a novel berberine-enzalutamide synergy. This framework resolves complex signaling dependencies, providing a scalable, transparent methodology for the rational discovery of effective combination therapies.

bioengineering↗

bioRxiv2026

Decoding the cell intrinsic and extrinsic roles of PRC2 in early embryogenesis

Early embryogenesis is accompanied by dynamic epigenetic modifications. While such dynamics are important in cell intrinsic regulation of gene expression, their extrinsic roles in mediating intercellular communication during early embryogenesis is less understood. Using the dTAG system, here we reveal previously underappreciated stage-specific functions of PRC2 in regulating pre-implantation and primordial germ cell (PGC) development. We demonstrate that PRC2 plays important roles in regulating maternal to zygotic transition (MZT), and epiblast (EPI) formation. By systematically analyzing H3K27me3 and H3K4me3 dynamics, we redefine the timing of bivalency establishment and uncover a stepwise mechanism governing bivalency acquisition in early embryogenesis. Moreover, PRC2 regulates proper PGC numbers in the EPI by controlling Esrrb expression in the extraembryonic ectoderm (ExE). Thus, our study uncovers a previously unknown cell-autonomous function of PRC2 in preimplantation development and its non-cell-autonomous impact in PGC number regulation, both through interplays between epigenetic-epigenetic and epigenetic-TFs networks.

developmental biology↗

bioRxiv2026

Gut-relevant short-chain fatty acids modulate host-pathogen dynamics of uropathogenic Escherichia coli at the colonic epithelial interface

Urinary tract infection (UTI) ranks among the most prevalent bacterial infections worldwide, affecting over 400 million people each year. Uropathogenic Escherichia coli (UPEC), the main aetiological cause of UTI, colonises the intestinal tract, which is thought to serve as a distal reservoir for gut-UTI recurrence. Despite this, the precise role of the gut in UTI recurrence is still not fully defined. Recent research investigating the gut-UTI axis has revealed that reduced abundance of gut commensals producing short-chain fatty acids (SCFAs, namely acetate, butyrate and propionate) is associated with recurrent and chronic UTI. We therefore aimed to investigate the impact of these gut commensal-derived metabolites on a diverse panel of UPEC strains, including well-studied prototypical strains (UTI89, CFT073), a non-pathogenic isolate E. coli K-12, and various clinical UTI isolates (from the urine of both symptomatic and asymptomatic individuals). We observed that SCFAs modulate bacterial growth kinetics in a concentration- and pH-dependent manner, by prolonging the lag phase without affecting final carrying capacity in vitro. These metabolites further suppressed bacterial swimming motility and biased the orientation of fimS, the phase variable switch for T1 fimbriae, under acidic conditions. In a human polarized, mucus-secreting intestinal infection model, SCFA treatment during UPEC challenge altered bacterial localization patterns, favouring planktonic over mucosal-associated populations, and preserved epithelial barrier function. Together, these in vitro findings demonstrate that SCFAs modulate key UPEC colonization-associated phenotypes and influence host-pathogen dynamics at the colonic epithelial interface. These results provide mechanistic insights into how depletion of SCFA-producing gut commensals may alter the intestinal reservoir environment in vitro and warrants further investigation into the role of gut-derived SCFAs in rUTI susceptibility.

microbiology↗

bioRxiv2026

Reliability and validity of multi-band multi-echo fMRI

Precision mapping of individual differences in human brain spontaneous activity is critical for characterizing brain function and guiding clinical translation. Multi-echo resting-state functional MRI (ME-rfMRI) has the potential to provide more reliable mapping of inter-individual differences in intrinsic brain function than conventional single-echo rfMRI (SE-rfMRI). However, the psychometric benefits of ME-rfMRI for mapping individual differences in spontaneous brain activity (SBA) have not been systematically investigated, which is fundamental for understanding the human brain in health and disease. To quantify the psychometric performance of ME-rfMRI in precisely mapping inter-individual variations in SBA, we employed a psychometric design. We scanned 27 healthy adults with both ME-rfMRI and SE-rfMRI to assess short-term (minutes) test-retest reliability, as well as validity across eyes-open (EO) and eyes-closed (EC) resting states. Our results demonstrate that ME-rfMRI improves reliability relative to SE-rfMRI by 10.8% for amplitude of low-frequency fluctuation (ALFF), 4.4% for regional homogeneity (ReHo), and 8.0% for voxel-mirrored homotopic connectivity (VMHC) in cortical regions, and by 12.5% for ALFF, 8.3% for ReHo, and 4.0% for VMHC in subcortical regions. This enhancement is achieved by increasing inter-individual variability while reducing intra-individual variability. Notably, ME-rfMRI accentuates inter-individual variability in the unimodal cortex and clearly delineates two parallel systems with distinct variability patterns within the motor cortex. Concurrently, ME-rfMRI increases effect sizes (4%-8%) for detecting individual differences between EO and EC resting states. Interestingly, ME-rfMRI reveals differential effects of eye closure on two intertwined systems in the primary motor and sensory cortices, extending previous findings. Computational simulations indicate that, compared to SE-rfMRI, ME-rfMRI facilitates experimental designs with reduced costs (i.e., 4%-11% smaller sample sizes) for precise mapping of individual differences. These findings establish, for the first time, the psychometric performance of ME-rfMRI measurements, supporting its potential utility in personalized neuroscience applications, including neurodevelopment and brain disorders.

neuroscience↗

bioRxiv2026

Selective class IIa HDAC inhibition reverses diastolic dysfunction in cardiometabolic HFpEF

Heart failure with preserved ejection fraction (HFpEF) is a highly prevalent cardiometabolic syndrome with yet no effective therapies. Here, we report that selectively class IIa histone deacetylases (HDACs) but no other classes of HDACs are enzymatically activated in hearts from HFpEF patients and cardiometabolic HFpEF animal models. Cell type-specific and enzymatic activity-specific genetic loss-of-function models of the cardiomyocyte-enriched class IIa HDAC family member HDAC4 and the pharmacological class IIa HDAC-selective inhibitor TMP195 prevent and reverse diastolic dysfunction and exercise intolerance in cardiometabolic HFpEF in vivo. In contrast to pan-HDAC inhibition no adverse effects are observed. Despite its well-known non-enzymatic role as transcriptional repressor, we found that specifically enzymatic activation of HDAC4 has little direct effects on cardiomyocyte-intrinsic gene expression. Instead, non-epigenetic actions lead to endothelial activation via altered cardiocrine signaling. We discovered that selective enzymatic class IIa HDAC inhibition is a new therapeutic concept to combat cardiac HFpEF.

molecular biology↗

bioRxiv2026

Cell-body curvature modulates stall frequency to enhance Vibrio cholerae swimming and chemotaxis through hydrogels

The swimming motility of Vibrio cholerae is a virulence factor that aids in breaching the mucus layer of the small intestine. V. cholerae cells have a curved cell shape and previous work demonstrated that loss of curvature decreases infectivity. Here we investigate the mechanism by which V. choleraes curvature affects single-cell motility within mucus-mimicking environments. Using a multiscale chemotaxis assay, we compared the chemotactic performance of wild-type curved cells (O1 El Tor C6706) and straight mutants under linear chemical gradients in liquid solutions, viscous solutions, and soft agar hydrogels. Our findings reveal that curved and straight V. cholerae exhibit similar swimming properties in liquid and purely viscous solutions but significantly differ in hydrogels, with curved cells demonstrating an 86% increase in average chemotactic drift compared to straight mutants in the same chemical gradients. Trajectory analysis indicates that swimming speeds are comparable, but straight mutants experience more frequent stalls, reducing the total time spent swimming. We also found that stalls further reduce chemotactic performances by imposing an average reorientation of bacteria down the chemical gradient, regardless of cell shape. In-silico coarse-grained molecular dynamics simulations corroborate these results and extend them over the wide range of intestinal mucus hydrogel stiffnesses. This model also identifies an optimal curvature for enhanced movement through hydrogel-like meshes that is close to the real median curvature of the pathogen. Our findings thus highlight the mechanisms underpinning cell shapes role in V. choleraes pathogenicity and underscore the necessity of studying bacterial behaviors under conditions that simulate host environments.

microbiology↗

bioRxiv2026

Dual-mode ClfA-targeting DARPin biologics protect against diverse methicillin-resistant Staphylococcus aureus strains

Staphylococcus aureus uses the adhesin clumping factor A (ClfA) to bind fibrinogen and promote invasive infection through two distinct interfaces: an exposed, low-afinity site on the N3 head domain and a buried, high-afinity "dock, lock, and latch" (DLL) trench that is exposed only under shear. This dual-interface architecture allows limited antibody penetration, as antibodies typically block only the exposed site. Here, we establish a dual-mode inhibition strategy that overcomes this constraint by combining a high-afinity ClfA-binding designed ankyrin repeat protein (DARPin) with a fibrinogen {gamma}-chain peptide capable of occupying the DLL trench. Using cell-free click display and kinetics-guided afinity maturation, we engineer DARPin-{gamma}-peptide fusion biologics that simultaneously block both fibrinogen-binding interfaces. These molecules inhibit ClfA-fibrinogen interactions, prevent methicillin-resistant S. aureus agglutination in human plasma, neutralize major clinical ClfA variants, and confer Fc-independent protection in a lethal murine bacteremia model. This work provides a strategy for targeting antibody-intractable force-activated staphylococcal adhesins.

molecular biology↗

bioRxiv2026

All-in-one Single-Cell Proteomic Analysis of Protein Alterations in Human Oocytes Undergoing in Vitro Aging

Study questionWhat specific proteomic changes and molecular markers associated with in vitro aging occur in human oocytes? Summary answerSingle-cell proteomic analysis revealed the protein dynamics during the in vitro aging of oocytes. Subsequent functional analysis highlighted key biological processes affected in aged oocytes and identified several genes as candidate key factors for oocyte and early embryo quality. What is known alreadyOvulated oocytes undergo a time-dependent degradation process if fertilization does not occur within a specific window. This aging process leads to morphological, molecular, and epigenetic changes that can compromise oocyte quality and subsequent embryo development. In previous studies, transcriptome sequencing in humans and mice has revealed serial changes in aging oocytes including oxidative stress, mitochondrial dysfunction, DNA damage, and alterations in cell cycle regulation. These changes can lead to apoptosis, chromosomal abnormalities, and epigenetic modifications, all of which negatively affect oocyte quality. However, research regarding protein level changes and regulatory mechanisms in human oocytes during in vitro aging remains unclear. Study design, size, durationUtilizing "All-in-one" single-cell proteomics, we investigated the protein expression levels in human oocytes at the germinal vesicle (GV) stage and metaphase II (M II) stage following 24 hours of in-vitro aging. We analyzed four groups of oocytes: fresh GV (n=8), in vitro-aged GV (n=9), fresh M II (n=11), and in vitro-aged M II (n=11). This approach allowed for a detailed comparison of proteomic changes associated with in vitro aging in oocytes at different developmental stages. Participants/materials, setting, methodsOocytes at GV and MII stage were collected for "All-in-one" single-cell quantitative proteomic respectively. Differentially expressed genes were analyzed using the R package DESeq2 or DEP (filtered with q-value[≤]0.05 and Foldchange[≥]1.5). EGSEA package was used to perform pathway analysis. Main results and the role of chanceThe proteomic analysis of fresh and in vitro-aged human GV and MII oocytes identified 3,268 proteins. In GV oocytes, compared to fresh samples, 73 proteins were upregulated and 90 were downregulated. Gene Ontology (GO) enrichment analyses revealed these DEPs were involved in key biological processes such as lysosome organization, spindle assembly and oxidative stress response. Gene Set Enrichment Analysis (GSEA) revealed a significant down regulation of genes associated with protein translation initiation and methylation pathways, while those in the apoptosis mitochondrial changes were upregulated. In MII oocytes, 63 proteins were upregulated and 69 were downregulated. GO analysis highlighted their involvement in cytoplasmic translation, ribosome biogenesis and oocyte development. GSEA showed that aged MII oocytes exhibited a downregulation of gene sets in protein translation but an upregulation in membrane fusion pathways compared to fresh oocytes. Furthermore, we identified proteins with consistent expression trends across both GV and MII stages, including MRFAP1 and MT2A, as candidate biomarkers for human oocyte aging in vitro. Limitations, reasons for cautionSingle cell proteomic techniques may not fully capture the dynamic range of proteins present within oocytes, leading to potential underrepresentation of low-abundance proteins that could play crucial roles. Furthermore, the heterogeneity within oocytes introduces variability that can obscure the identification of consistent proteomic signatures associated with oocyte quality or aging. Wider implications of the findingsThese findings not only provide an understanding of the protein changes underlying the in vitro aging of human oocytes but also offer potential biomarkers and intervention targets for future research and clinical applications in assisted reproductive technologies. Study funding/Competing interest(s)This project received funding from the National Natural Science Foundation of China (NO.82471693, 22574175); the Natural Science Foundation of Hunan Province (NO. 2024JJ4100), the Hunan Provincial Grant for Innovative Province Construction (2019SK4012), the Hundred Youth Talents Program of Hunan Province (to S.Z.), the Major Scientific Program of CITIC Group (No. 2023ZXKYB34100) and Scientific Research Foundation of Reproductive and Genetic Hospital of CITIC-XIANGYA (YNXM-202313, YNXM-202319, YNXM-202211). The authors have no conflicts of interest to declare.

developmental biology↗

bioRxiv2026

Genome-wide identification of heat shock proteins (HSP70) in the Cuban painted snail Polymita picta: evolutionary constraints face climate change challenges

Climate change poses a critical threat for biodiversity. Among ectothermal animals, terrestrial molluscs are considered highly vulnerable to temperature increase and drought due to their low vagility and specialized ecological requirements. In response to thermal stress, heat shock proteins (HSP70) play a crucial role in the response syndrome and phenotypic plasticity and mediate the adaptation to fluctuating environments. Here, we performed the first genome-wide identification and characterization of the HSP70 family in a Neotropical terrestrial gastropod of high conservation concern: the Cuban painted snail Polymita picta. Using comprehensive bioinformatic approaches, we identified HSP70 paralogs, analysed their structural features and assessed sequence variation, highlighting their potential relevance for thermoresistance. Our findings reveal an HSP70 repertoire of ten diversified sequences with signatures of functional specialization and possible adaptive variation linked to environmental temperature regimes. Using novel molecular resources, this pioneering analysis establishes a baseline for early warning systems, integrating stress-related biomarkers into conservation management and climate change adaptation strategies for threatened terrestrial molluscs.

genomics↗

bioRxiv2025

Extracellular matrix regulates lineage plasticity in prostate cancer through YAP/TEAD

Treatment-related neuroendocrine prostate cancer (NEPC) is an increasingly frequent mechanism of resistance to androgen receptor pathway inhibitor (ARPI) therapy in prostate adenocarcinoma (PRAD). This lineage transition is dependent on upregulation of the NE-specifying transcription factor ASCL1, typically in a genetic background of RB1 and TP53 loss. Here we identify extracellular matrix-integrin-YAP1/TEAD signaling as a critical brake on NEPC lineage transition. Deletion of Itgb1, the shared B1 subunit required for collagen and laminin-mediated integrin activation, is sufficient to induce ASCL1 and NE lineage gene expression, by activating LATS1/2 kinases with subsequent inactivation of YAP1/TEAD signaling. Conversely, restoration of YAP1/TEAD signaling by pharmacological LATS1/2 inhibition, or by expression of constitutively active YAP1/TAZ mutants, prevents or reverts NEPC lineage transition. NOTCH and AR cooperate with YAP/TEAD to repress ASCL1, such that combined inhibition leads to complete reprograming of PRAD into NEPC in vitro, providing a dynamic platform to dissect the molecular events responsible for lineage transition over time. We find that lineage transition is accompanied by a redistribution of FOXA1 and TEAD cistromes from PRAD to NEPC-specific enhancers and requires the pioneering activity of FOXA1. Thus, extracellular matrix/integrin signaling in the PRAD tumor microenvironment restrains NE lineage plasticity, highlighting a potential path for pharmacological inhibitors in modulating treatment-induced lineage change.

cancer biology↗

bioRxiv2025

Structural basis for hydrolytic splicing of a circularly permuted group II intron

Group II introns are self-splicing ribozymes that are considered the ancestors of the eukaryotic spliceosome. Unlike canonical group II introns that self-splice to generate linear exons and lariats, circularly permuted (CP) group II introns identified in various bacterial phyla perform back-splicing, resulting in the production of circular RNAs and branched products via branching pathway. Furthermore, CP introns may switch to a hydrolysis pathway resulting in distinct products to differentially regulate retrotransposition. In this study, we present biochemical data and high-resolution cryogenic electron microscopy (cryo-EM) structures of a CP group II intron from Comamonas testosteroni KF-1 (Cte 1), allowing mechanistic dissection of the switch from the branching pathway to the hydrolysis pathway, and enabling reconstruction of both steps of the hydrolysis pathway. The structures reveal that CP group II intron undergoes the hydrolysis pathway upon mutations of the branch point or splice sites (SS) due to rearrangements in the active site. Here, the branching nucleotide in domain D6 is retracted from its catalytically competent conformation, giving way to the nucleophilic water molecule to attack the 5' splice site. Furthermore, we visualized the intermediates of the second splicing step, which reveal the movement of domain D6 out of the way for the 3'-splicing to occur, closely resembling the second-step structures of the branching pathway. Finally, our structures provide direct evidence for domains D1-D3 acting as a scaffold in group II introns. Together, these findings visualize the complete hydrolysis pathway and offer a new strategy to engineer CP group II introns for circular RNA production, with potential applications in both basic research and therapeutic development.

biophysics↗

bioRxiv2025

A Comprehensive Treatment-Induced Resistance Atlas of Glioblastoma Reveals a Fibrotic Niche Shielding the Tumor from Immunotherapy

Therapeutic resistance in IDH-wildtype glioblastoma (GBM) is driven by an intricate interplay between cellular plasticity and protective microenvironmental niches. By constructing the GRIT-Atlas--a massive transcriptomic compendium encompassing nearly one million high-quality single cells across 17 cohorts--and cross-analyzing it with 48 independent Visium spatial transcriptomics sections, we discover a recurrent "Spatial Resistance Triad" comprising mesenchymal-like (MES-like) malignant cells, myeloid-derived suppressor cells (MDSCs), and collagen-secreting cancer-associated fibroblasts (CAFs). This large-scale spatial integration reveals that the triad physically fortifies microvascular proliferation (MVP) and pseudopalisading necrosis (PAN) niches. To substantiate these findings at true single-cell resolution, we deploy high-plex spatial molecular imaging (CosMx SMI) to map over 400,000 single cells across a clinical validation cohort. This high-resolution architecture firmly validates the triads geography and, critically, provides structural gradient evidence unmasking a spatiotemporal continuum wherein PAN emerges as a direct functional consequence of MVP advancement and subsequent vascular collapse. Mechanistically, stromal CAF-derived COL6A1 engages CD44 receptors on MES-like cells to accelerate a potent neural stemness cascade within these protective domains. Utilizing a blood-brain barrier (BBB)-penetrant multi-library compound screen, we identify Lacidipine as a multi-modal stromal disruptor that successfully silences CAF activation and halts matrix secretion. Incorporating Lacidipine into the standard chemo-immunotherapy backbone (TMZ + anti-CSF1R) completely dismantles the protective desmoplastic matrix niche, forcing a profound collapse of intracranial tumor burden and dramatically extending overall survival in orthotopic models. Collectively, our study leverages unprecedented single-cell and spatial scale to provide a definitive blueprint of GBM therapeutic evasion, establishing matrix-targeted intervention as a mandatory prerequisite for successful glioblastoma eradication.

cancer biology↗