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Sufi, J.

Publications and source records attributed to Sufi, J..

7 recordsLinked to original sources

Human Gastric Multi-Regional Assembloids Favour Functional Parietal Maturation and Allow Modelling of Antral Foveolar Hyperplasia

Patient-derived human organoids have the remarkable capacity to self-organise into more complex structures. However, to what extent gastric organoids can recapitulate human stomach physiological functions remain unexplored. Here, we report how region-specific gastric organoids can self-assemble into complex multi-regional assembloids showing functional response to drugs targeting the ATPase H+/K+ pump. The assembloids show preserved fundus, body, and antrum regional identity, and gastric-specific crosstalk pathways arise. The increased complexity and cross-communication between the different gastric regions, allow for the emergence of the elusive parietal cell type, responsible for the production of gastric acid, with functional response to drugs targeting the ATPase H+/K+ pump. Remarkably, we generated assembloids from PMM2-HIPKD-IBD paediatric patients (Phosphomannomutase 2 - Hyperinsulinemic hypoglycaemia and autosomal recessive polycystic kidney disease - Inflammatory bowel disease), a genetic condition found to be associated with unusual antral foveolar hyperplasia and hyperplastic polyposis. The cellular mechanisms behind such phenomena are poorly understood, and an exhaustive experimental model is needed. The {Delta}PMM2 multi-regional assembloid we have generated efficiently recapitulates hyperplastic-like antral regions, with decreased mucin secretion and glycosylated ATP4b, which results in impaired gastric acid secretion. Multi-regional gastric assembloids, generated using adult-stem cell-derived organoids, successfully recapitulate the structural and functional characteristics of the human stomach, offering a promising tool for studying gastric epithelial interactions and disease mechanisms previously challenging to investigate in primary models.

cell biology↗

SIGNAL-seq: Multimodal Single-cell Inter- and Intra-cellular Signalling Analysis

We present SIGNAL-seq (Split-pool Indexing siG-Nalling AnaLysis by sequencing): a multiplexed splitpool combinatorial barcoding method that simultaneously measures RNA and post-translational modifications (PTMs) in fixed single cells from 3D models. SIGNAL-seq PTM measurements are equivalent to mass cytometry and RNA gene detection is analogous to split-pool barcoding scRNA-seq. By measuring both mRNA ligand-receptor pairs and PTMs in single cells, SIGNAL-seq can simultaneously uncover inter- and intra-cellular regulation of tumour microenvironment plasticity.

cancer biology↗

Oncogenic PIK3CA corrupts growth factor signaling specificity

Pathological activation of the PI3K/AKT pathway is among the most frequent defects in human cancer and is also the cause of rare overgrowth disorders. Yet, there is currently no systematic understanding of the quantitative flow of information within PI3K/AKT signaling and how it is perturbed by disease-causing mutations. Here, we develop scalable, single-cell approaches for systematic analyses of signal processing within the PI3K pathway, enabling precise calculations of its information transfer for different growth factors. Using genetically-engineered human cell models with allele dose-dependent expression of PIK3CAH1047R, we show that this oncogene is not a simple, constitutive pathway activator but a context-dependent modulator of extracellular signal transfer. PIK3CAH1047Rreduces information transmission downstream of IGF1 while selectively enhancing EGF-induced signaling and transcriptional responses. This leads to a gross reduction in signaling specificity, akin to "blurred" signal perception. The associated increase in signaling heterogeneity promotes phenotypic diversity in a human cervical cancer cell line model and in human induced pluripotent stem cells. Collectively, these findings and the accompanying methodological advances lay the foundations for a systematic mapping of the quantitative mechanisms of PI3K/AKT-dependent signal processing and phenotypic control in health and disease. One-sentence summarySingle-cell signaling and information theoretic analyses reveal that oncogenic PI3K/AKT activation leads to a gross reduction in signaling specificity, context-dependent EGF response amplification as well as increased phenotypic heterogeneity.

systems biology↗

A Single-cell Perturbation Landscape of Colonic Stem Cell Polarisation

Cancer cells are regulated by oncogenic mutations and microenvironmental signals, yet these processes are often studied separately. To functionally map how cell-intrinsic and cell-extrinsic cues co-regulate cell-fate in colorectal cancer (CRC), we performed a systematic single-cell analysis of 1,071 colonic organoid cultures regulated by 1) CRC oncogenic mutations, 2) microenvironmental fibroblasts and macrophages, 3) stromal ligands, and 4) signalling inhibitors. Multiplexed single-cell analysis revealed a stepwise epithelial differentiation landscape dictated by combinations of oncogenes and stromal ligands, spanning from fibroblast-induced Clusterin (CLU)+ revival colonic stem cells (revCSC) to oncogene-driven LRIG1+ hyper-proliferative CSC (proCSC). The transition from revCSC to proCSC is regulated by decreasing WNT3A and TGF-{beta}-driven YAP signalling and increasing KRASG12D or stromal EGF/Epiregulin-activated MAPK/PI3K flux. We find APC-loss and KRASG12D collaboratively limit access to revCSC and disrupt stromal-epithelial communication - trapping epithelia in the proCSC fate. These results reveal that oncogenic mutations dominate homeostatic differentiation by obstructing cell-extrinsic regulation of cell-fate plasticity. HighlightsO_LI1,071-condition single-cell transition map of colonic stem cell polarisation regulated by oncogenic and mircoenvironmental cues. C_LIO_LIFibroblasts polarise WT colonic epithelia towards Clu+ revCSC via TGF-{beta}1 and YAP signalling. C_LIO_LIAPC-loss and KRASG12D drive a Birc5+, Lrig1+, and Ephb2+ proCSC fate via MAPK and PI3K. C_LIO_LIOncogenic mutations disrupt stromal regulation of epithelial plasticity, trapping cells in the proCSC fate. C_LI

cancer biology↗

Cancer-Associated Fibroblasts Regulate Patient-Derived Organoid Drug Responses

Patient-derived organoids (PDOs) can model personalized therapy responses, however current screening technologies cannot reveal drug response mechanisms or study how tumor microenvironment cells alter therapeutic performance. To address this, we developed a highly-multiplexed mass cytometry platform to measure post translational modification (PTM) signaling in >2,500 colorectal cancer (CRC) PDOs and cancer-associated fibroblasts (CAFs) in response to clinical therapies at single-cell resolution. To compare patient- and microenvironment-specific drug responses in thousands of single-cell datasets, we developed Trellis -- a highly-scalable, hierarchical tree-based treatment effect analysis method. Trellis single-cell screening revealed that on-target cell-cycle blockage and DNA-damage drug effects are common, even in chemorefractory PDOs. However, drug-induced apoptosis is patient-specific. We found drug-induced apoptosis does not correlate with genotype or clinical staging but does align with cell-intrinsic PTM signaling in PDOs. CAFs protect chemosensitive PDOs by shifting cancer cells into a slow-cycling cell-state and CAF chemoprotection can be reversed by inhibiting YAP. HighlightsO_LI>2,500 single-cell PTM signaling, DNA-damage, cell-cycle, and apoptosis responses from drug-treated PDOs and CAFs. C_LIO_LITrellis: hierarchical tree-based treatment effect method for single-cell screening analysis. C_LIO_LIPDOs have patient-specific drug responses that align with cell-intrinsic PTM signaling states. C_LIO_LICAFs chemoprotect PDOs by altering PDO cell-state via YAP signaling. C_LI

cancer biology↗

Enhanced functionality of low-affinity CD19 CAR T-cells is associated with activation priming and a polyfunctional cytokine phenotype

We recently described a low-affinity second-generation CD19 chimeric antigen receptor (CAR) CAT that showed enhanced expansion, cytotoxicity, and anti-tumour efficacy compared to the high-affinity (FMC63 based) CAR used in Tisagenlecleucel, in pre-clinical models. Furthermore, CAT demonstrated an excellent toxicity profile, enhanced in vivo expansion, and long-term persistence in a Phase I clinical study. To understand the molecular mechanisms behind these properties of CAT CAR T-cells, we performed a systematic in vitro characterization of the transcriptomic (RNA-seq) and protein (CyTOF) changes occurring in T-cells expressing low-affinity vs high-affinity CD19 CARs following stimulation with CD19-expressing cells. Our results show that CAT CAR T-cells exhibit enhanced activation to CD19 stimulation and a distinct transcriptomic and protein profile, with increased activation and cytokine polyfunctionality compared to FMC63 CAR T-cells. We demonstrate that the enhanced functionality of low-affinity CAT CAR T-cells is a consequence of an antigen-dependent priming induced by residual CD19-expressing B-cells present in the manufacture.

cancer biology↗

Single-Cell Signalling Analysis of Heterocellular Organoids

Organoids are powerful biomimetic tissue models. Despite their widespread adoption, methods to analyse cell-type specific post-translational modification (PTM) signalling networks in organoids are absent. Here we report multivariate single-cell analysis of cell-type specific signalling networks in organoids and organoid co-cultures. Simultaneous measurement of 28 PTMs in >1 million single small intestinal organoid cells by mass cytometry reveals cell-type and cell-state specific signalling networks in stem, Paneth, enteroendocrine, tuft, goblet cells, and enterocytes. Integrating single-cell PTM analysis with Thiol-reactive Organoid Barcoding in situ (TOBis) enables high-throughput comparison of signalling networks between organoid cultures. Multivariate cell-type specific PTM analysis of colorectal cancer tumour microenvironment organoids reveals that shApc, KrasG12D, and Trp53R172H cell-autonomously mimic signalling states normally induced by stromal fibroblasts and macrophages. These results demonstrate how standard mass cytometry workflows can be modified to perform high-throughput multivariate cell-type specific signalling analysis of healthy and cancerous organoids.

cell biology↗