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Del Nery, E.

Publications and source records attributed to Del Nery, E..

13 recordsLinked to original sources

Static2Dynamic: Reconstructing videos of unobservable cellular, developmental, and disease processes

A fundamental limitation in biology is that many of its most important processes unfold as visual dynamics that cannot be directly observed. Development, tissue remodeling, and disease progression often occur deep in living organisms, over extended timescales, and at cellular resolution beyond the reach of current live imaging technologies. As a result, much of biology remains accessible only through static snapshots, while the underlying phenotypic trajectories and visual transformations remain hidden. Here, we introduce Static2Dynamic, a general framework to reconstruct unseen biological dynamics from sets of cross-sectional image data. Starting from time-unpaired static samples, Static2Dynamic first recovers a continuous pseudotime for individual images in a time-discriminative deep representation space, then learns a generative model of images conditionally to the underlying process, and finally reconstructs temporally coherent videos initialized from real samples. This makes it possible to infer past and future visual states of a static image and to simulate complete trajectories of cellular, developmental, and disease processes that were never directly recorded. We quantitatively validate Static2Dynamic on two large-scale experimental microscopy video datasets generated specifically for benchmarking, enabling direct comparison of inferred pseudotime trajectories and reconstructed videos against ground-truth biological dynamics. We further show that the framework generalizes across biological scales, organisms, and imaging modalities, including processes inaccessible to continuous live observation. More broadly, Static2Dynamic establishes the foundations of pseudotime microscopy, a new paradigm for reconstructing the visual and temporal dynamics of biological processes directly from static imaging data, thereby expanding the observable space of living systems beyond current experimental limits.

bioinformatics↗

Large Scale Cell Painting Guided Compound Selection Reveals Activity Cliffs and Functional Relationships

Traditional structure-based pre-screen compound selection relies on the assumption that chemical similarity implies similar biological activity. This paradigm narrows the exploration of chemical space and often fails to account for functional convergence, where structurally diverse compounds act through distinct targets to produce similar phenotypic effects. As a result, compounds with therapeutic potential may be overlooked. To overcome this constraint, we introduce a training-free, transfer learning-based method for large scale compound preselection that leverages deep phenotypic profiling of human cells. Notably, this enables robust pairwise comparison of phenotypic signatures across any source of the entire JUMP-CP, the largest publicly available cell painting dataset (112,480 compounds), preserving biological signals while mitigating batch effects. Validated across 65 high-throughput assays--including in vitro and in cellulo systems--our method provides efficient pre-screen enrichment of biologically active compounds, bypassing the blind spots of structure-centric approaches. Interestingly, because it is large scale, it also allows for a comprehensive analysis of structure-phenotypic activity relationships, revealing potentially thousands of compound activity cliffs, where minimal chemical changes in structure may result in profound phenotypic shifts. We show that these cliffs capture subtle, atom-level determinants of bioactivity that cannot be accessed by structure-based models. Furthermore, we demonstrate that structurally diverse compounds targeting different genes in the same biological pathway can induce either convergent or opposite phenotypes--a phenomenon validated across 30 pathways, hundreds of genes, and thousands of compounds. Finally, to support the broader community, we propose Phenoseeker, a web-based tool enabling instant retrieval of JUMP-CP compounds with similar phenotypic profiles. Together, these findings position phenotypic profiling not merely as a complementary tool, but as a transformative and scalable framework for navigating chemical space through a biological lens. By capturing rich morphological signatures that reflect functional outcomes--regardless of structural similarity--this approach enables the discovery of bioactive compounds, novel mechanisms of action, and unexpected target-pathway relationships. Applied at the scale of the JUMP-CP dataset, phenotypic profiling emerges as a powerful strategy for prioritizing compounds, illuminating activity cliffs, and accelerating the identification of therapeutically relevant candidates across diverse biological contexts.

bioinformatics↗

Integrated multiomic profiling reveals SWI/SNF subunit-specific pathway alterations and targetable vulnerabilities

Mutations in subunits of the SWItch Sucrose Non-Fermentable (SWI/SNF) chromatin remodeling complex occur in {approx}20% of cancers and represent a highly unmet medical need. To identify novel therapeutic approaches, we systematically characterized transcriptomic and proteomic changes caused by the loss of SWI/SNF subunits or other epigenetic enzymes in isogenic cell lines, which we subsequently integrated with high-throughput drug screening and independent genetic screens of the DepMap project. Using an optimized bioinformatics pipeline for pathway enrichment, we identified Metabolism of proteins as the most frequently dysregulated Reactome pathway category in SWI/SNF-defective cell lines. Drug screening and multiomic integration revealed multiple chemicals selectively cytotoxic for SWI/SNF-defective models, including CBP/EP300 or mitochondrial respiration inhibitors. A novel algorithm for the analysis of DepMap CRISPR screens independently identified synthetic lethality between SWI/SNF defects and EP300 or mitochondrial respiration genes, which we further revalidated in disease-relevant models. These results unravel novel genetic dependencies for SWI/SNF-defective cancers.

cancer biology↗

Polθ is phosphorylated by Polo-like kinase 1 (PLK1) to enable repair of DNA double strand breaks in mitosis

DNA double strand breaks (DSBs) are deleterious lesions that challenge genome integrity. To mitigate this threat, human cells rely on the activity of multiple DNA repair machineries that are tightly regulated throughout the cell cycle1. In interphase, DSBs are mainly repaired by non-homologous end joining (NHEJ) and homologous recombination (HR)2. However, these pathways are completely inhibited in mitosis3-5, leaving the fate of mitotic DSBs unknown. Here we show that DNA polymerase theta (Pol{theta})6 repairs mitotic DSBs and thereby maintains genome integrity. In contrast to other DSB repair factors, Pol{theta} function is activated in mitosis upon phosphorylation by the Polo-like kinase 1 (PLK1). Phosphorylated Pol{theta} is recruited to mitotic DSBs, where it mediates joining of broken DNA ends, while halting mitotic progression. The lack of Pol{theta} leads to a shortening of mitotic duration and defective repair of mitotic DSBs, resulting in a loss of genome integrity. In addition, we identify mitotic Pol{theta} repair as the underlying cause of the synthetic lethality between Pol{theta} and HR. Our findings reveal the critical importance of mitotic DSB repair for maintaining genome stability.

cell biology↗

COMBINATION THERAPIES TARGETING ALK-ABERRANT NEUROBLASTOMA IN PRECLINICAL MODELS.

BackgroundALK activating mutations are identified in approximately 10% of newly diagnosed neuroblastomas and ALK amplifications in a further 1-2% of cases. Lorlatinib, a third generation ALK inhibitor, will soon be given alongside induction chemotherapy for children with ALK-aberrant neuroblastoma. However, resistance to single agent treatment has been reported and therapies that improve the response duration are urgently required. We studied the preclinical combination of lorlatinib with chemotherapy, or with the MDM2 inhibitor, idasanutlin, as recent data has suggested that ALK inhibitor resistance can be overcome through activation of the p53-MDM2 pathway. AimsTo study the preclinical activity of ALK inhibitors alone and in combination with chemotherapy or idasanutlin. MethodsWe compared different ALK inhibitors in preclinical models prior to evaluating lorlatinib in combination with chemotherapy or idasanutlin. We developed a triple chemotherapy (CAV: cyclophosphamide, doxorubicin and vincristine) in vivo dosing schedule and applied this to both neuroblastoma genetically engineered mouse models (GEMM) and patient derived xenografts (PDX). ResultsLorlatinib in combination with chemotherapy was synergistic in immunocompetent neuroblastoma GEMM. Significant growth inhibition in response to lorlatinib was only observed in the ALK-amplified PDX model with the highest ALK expression. In this PDX lorlatinib combined with idasanutlin resulted in complete tumor regression and significantly delayed tumor regrowth. ConclusionOur study suggests that in neuroblastoma, high ALK expression could be associated with response to lorlatinib and either chemotherapy or idasanutlin. The synergy between MDM2 inhibition and ALK inhibition warrants further evaluation of this combination as a potential clinical approach for children with neuroblastoma. STATEMENT OF TRANSLATIONAL RELEVANCENeuroblastoma is a pediatric tumor of the developing sympathetic nervous system. Around 50% of high-risk neuroblastoma patients are curable. Mutations or amplification of Anaplastic Lymphoma Kinase (ALK) have emerged as a marker with which to further risk-stratify patients. The ALK inhibitor lorlatinib will soon be used alongside chemotherapy in upfront treatment of high-risk patients with ALK-aberrant disease. In this preclinical study, we used a panel of ALK aberrant neuroblastoma models to evaluate ALK inhibitors focusing on lorlatinib in combination with conventional chemotherapy and the small molecule MDM2 inhibitor idasanutlin. In both approaches we found synergy in models with high basal ALK expression without MAPK pathway alterations. We conclude that in neuroblastoma the level of ALK expression could be an additional biomarker predictive of clinical response to ALK inhibitors.

cancer biology↗

Revealing invisible cell phenotypes with conditional generative modeling

Biological sciences, drug discovery and medicine rely heavily on cell phenotype perturbation and observation. Aside from dramatic events such as cell division or cell death, most cell phenotypic changes that keep cells alive are subtle and thus hidden from us by natural cell variability: two cells in the same condition already look different. While we show that deep learning models can leverage invisible features from microscopy images, to discriminate between close conditions, these features can yet hardly be observed and therefore interpreted. In this work, we show that conditional generative models can be used to transform an image of cells from any one condition to another, thus canceling cell variability. We visually and quantitatively validate that the principle of synthetic cell perturbation works on discernible cases such as high concentration drug treatments, nuclear translocation and golgi apparatus assays. We then illustrate its effectiveness in displaying otherwise invisible cell phenotypes triggered by blood cells under parasite infection, the presence of a disease-causing pathological mutation in differentiated neurons derived from iPSCs or low concentration drug treatments. The proposed approach, easy to use and robust, opens the door to the accessible discovery of biological and disease biomarkers.

bioinformatics↗

Prostaglandin E1 as therapeutic molecule for Nephronophthisis and related ciliopathies

Nephronophthisis (NPH) is an autosomal recessive tubulointerstitial nephropathy belonging to the ciliopathy disorders and known as the most common cause of hereditary end-stage renal disease in children. Yet, no curative treatment is available. The major gene, NPHP1, encodes a protein playing key functions at the primary cilium and cellular junctions. Using an in cellulo medium-throughput drug-screen, we identified 51 FDA-approved compounds and selected 11 for their physicochemical properties, including prostaglandin E1 (PGE1). PGE1 was further validated to rescue ciliogenesis in immortalized patient NPHP1-/- urine-derived renal tubular cells and corroborated by the effects of its analog PGE2. The two molecules reduced pronephric cyst occurrence in vivo in nphp4 zebrafish model, and PGE1 treatment in Nphp1-/- mice led to a significant reduction of renal tubular dilatations, partially restoring cilia length within tubules. Finally, comparative transcriptomics allowed identification of key molecules downstream PGE1. Altogether, our drug-screen strategy led to the identification of PGE1 as the first potential therapeutic molecule for NPH-associated ciliopathies. Significant statementJuvenile nephronophthisis (NPH) is a renal ciliopathy due to a dysfunction of primary cilia and a common genetic cause of end-stage renal disease in children and young adults. No curative treatment is available. This paper describes the identification of Prostaglandin E1 (PGE1) as the first potential therapeutic molecule for NPH-associated ciliopathies. We demonstrated that PGE1 rescues defective ciliogenesis and ciliary composition in NPHP1-/- patient urine-derived renal tubular cells. Furthermore, PGE1 improves ciliary and kidney phenotypes in our NPH zebrafish and Nphp1-/- mouse models. Finally, in vitro experiments as well as transcriptomic analyses pointed out several pathways downstream PGE1 as cAMP, cell-cell/cell-matrix adhesion or actin cytoskeleton. Altogether, our findings provide a new alternative for treatment of NPH.

cell biology↗

Homosalate boosts the release of tumor-derived Extracellular Vesicles with anti-anoikis properties

Eukaryotic cells, including cancer cells, secrete highly heterogeneous populations of extracellular vesicles (EVs). EVs could have different subcellular origin, composition and functional properties, but tools to distinguish between EV subtypes are scarce. Here, we tagged CD63- or CD9-positive EVs secreted by triple negative breast cancer cells with Nanoluciferase enzyme, to set-up a miniaturized method to quantify secretion of these two EV subtypes directly in the supernatant of cells. We performed a cell-based high-content screening to identify clinically-approved drugs able to affect EV secretion. One of the identified hits is Homosalate, an anti-inflammatory drug found in sunscreens which robustly increased EVs release. Comparing EVs induced by Homosalate with those induced by Bafilomycin A1, we discovered that: 1) the two drugs act on EVs generated in distinct subcellular compartments and 2) EVs released upon treatment with Homosalate, but not with Bafilomycin A1, conferred anti-anoikis properties to another recipient tumor cell line. In conclusion, we identified a new drug modifying EV release and demonstrated that under influence of different drugs, triple negative breast cancer cells release EV subpopulations from different subcellular origins harboring distinct functional properties.

cell biology↗

Discovery of genes that modulate flavivirus replication in an interferon-dependent manner

Establishment of the interferon (IFN)-mediated antiviral state provides a crucial initial line of defense against viral infection. Numerous genes that contribute to this antiviral state remain to be identified. Using a loss-of-function strategy, we screened an original library of 1156 siRNAs targeting 386 individual curated human genes in stimulated microglial cells infected with Zika virus (ZIKV), an emerging RNA virus that belongs to the flavivirus genus. The screen recovered twenty-one potential host proteins that modulate ZIKV replication in an IFN-dependent manner, including the previously known IFITM3 and LY6E. Further characterization contributed to delineate the spectrum of action of these genes towards other pathogenic RNA viruses, including Hepatitis C virus and SARS-CoV-2. Our data revealed that APOL3 acts as a proviral factor for ZIKV and several other related and unrelated RNA viruses. In addition, we showed that MTA2, a chromatin remodeling factor, possesses potent flavivirus-specific antiviral functions. Our work identified previously unrecognized genes that modulate the replication of RNA viruses in an IFN-dependent way, opening new perspectives to target weakness points in the life cycle of these viruses.

microbiology↗

Small molecule enhancers of endosome-to-cytosol import augment anti-tumour immunity

Efficient cross-presentation of antigens by dendritic cells (DCs) is critical for initiation of anti-tumour immune responses. Yet, several steps of antigen intracellular traffic during cross-presentation are incompletely understood: in particular, the molecular mechanisms and the relative importance of antigen import from endocytic compartments into the cytosol. Here, we asked whether antigen import into the cytosol is rate-limiting for cross-presentation and anti-tumour immunity. By screening 700 FDA-approved drugs, we identified 37 import enhancers. We focused on prazosin and tamoxifen, and generated proteomic organellar maps of drug-treated DCs, covering the subcellular localisations of over 2000 proteins. By combining organellar mapping, quantitative proteomics, microscopy, and bioinformatics, we conclude that import enhancers undergo lysosomal trapping leading to membrane permeation and antigen release into the cytosol. Enhancing antigen import facilitates cross-presentation of both soluble and cell-associated antigens. Systemic administration of prazosin also led to reduced growth of MC38 tumours and to a synergistic effect with checkpoint immunotherapy in a melanoma model. Thus, inefficient antigen import into the cytosol limits antigen cross-presentation, restraining the potency of anti-tumour immune responses and efficacy of checkpoint blockers. HighlightsO_LIQuinazolamine derivatives are potent enhancers of antigen import into the cytosol C_LIO_LIAntigen import enhancement occurs as a consequence of lysosomal trapping C_LIO_LIAntigen import enhancers facilitate cross-presentation and synergise with PD-L1 C_LIO_LIProteomic organellar maps of cDC1s as a tool to detect biological effects of drugs C_LI O_FIG O_LINKSMALLFIG WIDTH=180 HEIGHT=200 SRC="FIGDIR/small/079491v1_ufig1.gif" ALT="Figure 1"> View larger version (38K): org.highwire.dtl.DTLVardef@1d55245org.highwire.dtl.DTLVardef@c3d43org.highwire.dtl.DTLVardef@189fbc8org.highwire.dtl.DTLVardef@1f1280e_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

Domain-invariant features for mechanism of action prediction in a multi-cell-line drug screen

High Content Screening is an important tool in drug discovery and characterisation. Often, high content drug screens are performed on one single cell line. Yet, a single cell line cannot be thought of as a perfect disease model. Many diseases feature an important molecular heterogeneity. Consequently, a drug may be effective against one molecular subtype of a disease, but less so against another. To characterise drugs with respect to their effect not only on one cell line but on a panel of cell lines is therefore a promising strategy to streamline the drug discovery process. The contribution of this paper is twofold. First, we investigate whether we can predict drug mechanism of action (MOA) at the molecular level without optimisation of the MOA classes to the screen specificities. To this end, we benchmark a set of algorithms within a conventional pipeline, and evaluate their MOA prediction performance according to a statistically rigorous framework. Second, we extend this conventional pipeline to the simultaneous analysis of multiple cell lines, each manifesting potentially different morphological baselines. For this, we propose multitask autoencoders, including a domain-adaptive model used to construct domain-invariant feature representations across cell lines. We apply these methods to a pilot screen of two triple negative breast cancer cell lines as models for two different molecular subtypes of the disease.

bioinformatics↗

MYO1C facilitates arrival at the Golgi apparatus through stabilization of branched actin

We aim at the identification of myosin motor proteins that control trafficking at the Golgi apparatus. In addition to the known Golgi-associated myosins MYO6, MYO18A and MYH9 (myosin IIA), we identify MYO1C as a novel player at the Golgi. We demonstrate that depletion of MYO1C induces Golgi apparatus fragmentation and decompaction. MYO1C accumulates at dynamic structures around the Golgi apparatus that colocalize with Golgi-associated actin dots. Interestingly, MYO1C depletion leads to loss of cellular F-actin, and Golgi apparatus decompaction is also observed after the inhibition or loss of the Arp2/3 complex. We show that the functional consequences of MYO1C depletion is a delay in the arrival of incoming transport carriers, both from the anterograde and retrograde routes. We propose that MYO1C stabilizes branched actin at the Golgi apparatus that facilitates the arrival of incoming transport at the Golgi.

cell biology↗

Differential screening identifies molecules specifically inhibiting CCR5 transport to the cell surface and HIV infection

Proteins destined to the cell surface are conveyed through membrane-bound compartments using the secretory pathway. Multiple secretory routes exist in cells, which paves the way to the development of inhibitory molecules able to specifically perturb the transport of a chosen cargo. We used differential high-content screening of chemical libraries to identify molecules reducing the secretion of CCR5, the major co-receptor for HIV-1 entry. Three molecules strongly affected the anterograde transport of CCR5, without inhibiting the transport of the related G protein-coupled receptors CCR1 and CXCR4. These three molecules perturb the transport of endogenous CCR5 and decrease the entry of HIV in human primary target cells. Two molecules were found to share the same mode of action, inhibiting palmitoylation of CCR5. Our results demonstrate that secretory routes can be specifically targeted which allows to envisage novel strategies to provoke the intracellular retention or rerouting of secretory proteins involved in disease development.

cell biology↗