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Kurek, D.

Publications and source records attributed to Kurek, D..

6 recordsLinked to original sources

Modeling Hepatocellular Carcinoma and its microenvironment on a chip

Hepatocellular carcinoma (HCC) is the most common type of liver cancer. Its incidence is increasing and is closely related to advanced liver disease. Interactions in the HCC microenvironment between tumor cells and the associated stroma actively regulate tumor initiation, progression, metastasis, and therapy response. Effective drug development increasingly requires advanced models that can be utilized in the earliest stages of compound and target discovery. Here we report a phenotypic screen on an advanced HCC patient-derived chip (PDChip) model. The vascularized HCC PDChip models include relevant cellular players of the HCC microenvironment. We assessed the effect of 28 treatment conditions on a panel of 8 primary HCC tumors and 2 cell lines. Approximately 1200 HCC PDchips were grown under perfusion flow, exposed to treatments, and subsequently assessed for viability, tumor-associated vasculature responses and chemokine and cytokine changes. Although the SoC therapeutics sorafenib and lenvatinib reduced culture viability and produced profound changes in the organization of the vascular beds, they did not affect the tumor cell population in these cultures. Atorvastatin, a 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor, reduced tumor viability but did not affect vascular bed organization. Sorafenib, lenvatinib and atorvastatin also affected chemokine and cytokine release. Tocilizumab, galunisertib, and vactosertib decreased the level of IL6, a relevant prognostic marker for HCC, while IL6 was increased by halofuginone. In conclusion, HCC PDChip models enabled a detailed evaluation of drug-induced responses in the tumor and associated microenvironment, highlighting their importance in preclinical research for understanding diseases and developing new drugs.

bioengineering↗

Dynamic modelling of EWS::FLI1 fluctuations reveals molecular determinants of phenotypic tumor plasticity and prognosis in Ewing sarcoma

The mechanisms underlying tumor cell plasticity driving drug resistance and disease progression remain poorly understood. In Ewing sarcoma (EwS), variations in EWS::FLI1 (EF) activity have been associated with epithelial-mesenchymal plasticity (EMP). Using degron technology, we titrated endogenous EF in an EwS cell line and linked phenotypic states to distinct EF thresholds. Strikingly, modest EF depletion promoted a pro-metastatic phenotype, that diminished upon near-complete EF loss. Nascent RNA sequencing revealed distinct gene clusters with heterogenous response patterns to varying EF dosage. Target genes most sensitive to subtle EF depletion contained GGAA microsatellites in EF-bound enhancers. Furthermore, we identified Kruppel-like zinc-finger transcription factors associated with EF-repressed EMP genes. Transient EF depletion followed by rapid restoration to simulate oncoprotein fluctuations identified persistently dysregulated genes associated with poor prognosis. This study underscores the therapeutic challenge of insufficient EF inhibition and provides a foundation for exploiting oncoprotein dynamics to uncover therapeutic vulnerabilities in fusion-driven cancers. Beyond EwS, our results underscore the broader impact of oncoprotein dosage dynamics in cancers with otherwise quiet genomes. SIGNIFICANCEWe report EwS as a paradigm for the importance of oncogene fluctuations in tumor cell plasticity and disease progression. Effective therapeutic strategies must ensure complete EF depletion to prevent inadvertent metastasis.

cancer biology↗

A Novel Human Distal Tubuloid-On-A-Chip Model For Investigating Sodium And Water Transport Mechanisms

The distal segments of the nephron play a central role in regulating water and electrolyte balance, making them critical targets for therapeutic interventions. Damage to these segments is associated with significant health consequences. Studying their (patho)physiology in vivo remains challenging due to the kidneys complex architecture. Recent advances led to the development of more representative in vitro models, including human tubuloids that replicate the phenotype of distal tubule segments. Additionally, novel high throughput microfluidic systems, which support 3D cell culture under flow conditions, provide a platform for closely mimicking in vivo environments. This study presents an enhanced in vitro model of human distal tubule segments by integrating tubuloid culture with the OrganoPlate(R) platform. Tubuloid cells were grown as three-dimensional tubules against a collagen-1 matrix and under alternating flow condition, then differentiated into a distal phenotype. qPCR analysis demonstrated enhanced expression of distal segment markers in 3D flow cultures compared to traditional 2D models. Immunohistochemistry confirmed the formation of a leak-tight, highly polarized epithelium with apical and basolateral localization of key electrolyte transporters. Functional integrity was verified by restricted dextran diffusion and increased transepithelial resistance. Radiolabeled sodium assays revealed active and selective sodium transport mediated by apical epithelial sodium channels (ENaC) and basolateral Na/K ATPase. Sodium transport was followed by water movement, evidenced by dome formation beneath the epithelial monolayer. The models utility was further demonstrated in toxicity studies using trimethoprim, an antibiotic that inhibits ENaC function, resulting in reduced sodium transport and dome formation. This system enables the study of primary human tubule cells with a distal phenotype under controlled flow conditions, allowing direct assessment of water and salt transport. The model provides a valuable tool for investigating distal nephron (patho)physiology and facilitates high-throughput drug development and toxicity testing.

bioengineering↗

Validation of an MPS based intestinal cell culture model for the evaluation of drug-induced toxicity

The potential for drug-induced gastrointestinal (GI) toxicity is significant, since the GI tract is one of the first barriers which come in to contact with oral drugs. In pharmaceutical research, the complex behavior of human intestinal cells is traditionally investigated using 2D cultures, in which one cell type grows under static conditions. With the development of advanced microphysiological systems (MPS) more in vivo like conditions can be generated which increase the physiological nature and also the predictive validity of these models. Caco-2 cells are known for their capability to build tight junctions. These connections are responsible for the maintenance of intestinal homeostasis and can be used as a specific safety endpoint, by measuring the Trans Epithelial Electrical Resistance (TEER), for the investigation of drug-induced GI toxicity. Compared to a widely used Caco-2 cell 2D Transwell model, the advanced MPS model (Mimetas OrganoPlate(R)) allows for the recapitulation of the enterocyte cell layer of the intestinal barrier as the Caco-2 cells grow in a tubular structure through which the medium continuously flows. The OrganoPlate(R) intestinal model was qualified to be implemented as a routine test system for the early prediction of drug-induced GI toxicity based on the measurement of the tightness of the cell layer by measuring changes in the TEER. For this qualification 23 well known compounds as well as a positive, negative and solvent control were selected. The compounds were selected based on their known effect on the GI system (chemotherapeutics, tight junction disruptor, liver toxins, controls, NSAIDs and a mixed group of drugs). The TEER values were measured 4h and 24h after treatment. In parallel the cell viability was determined after 24h to be able to distinguish between an unspecific cytotoxic effect or direct tight junction damage. Overall, from the 23 tested compounds, 15 showed the expected outcome, i.e.,the compound led to a decrease of the TEER for the positive control compounds, or the TEER value remained stable after treatment with non-GI-toxic compounds. In summary, this MPS model allowed the recapitulation of the human intestinal GI barrier and will enable a faster and more robust assessment of drug-induced damage in the GI tract.

pharmacology and toxicology↗

A microvascularized in vitro liver model for disease modeling and drug discovery

Drug discovery for complex liver diseases faces alarming attrition rates. The lack of non-clinical models that recapitulate key aspects of liver (patho)-physiology is likely contributing to the inefficiency of developing effective treatments. Of particular notice is the common omission of an organized microvascular component despite its importance in maintaining liver function and its involvement in the development of several pathologies. Increasing the complexity of in vitro models is usually associated with a lack of scalability and robustness which hinders their implementation in drug development pipelines. Here, we describe a comprehensive liver MPS model comprising stellates, liver-derived endothelial cells and hepatocytes conceived within a scalable and automated platform. We show that endothelial cells self-organize in a microvascular network when co-cultured with stellates in a hydrogel. In a tri-culture, hepatocytes polarize accordingly, with a basolateral side facing blood vessels and an apical side facing bile-canaliculi-like structures. Stellates interact and surround the hollow microvessels. Steatosis was induced by exogenous administration of fatty acids which could be prevented by co-administration of firsocostat. Administration of TGF-{beta} resulted in an activated stellate cells phenotype which could be prevented by the co-administration of SB-431542. The model was implemented on a microtiter plate format comprising 64 chips which enabled the development of a fully automated, multiplexed fibrosis assay with a robust Z factor suitable for high-throughput applications.

bioengineering↗

Scalable production of tissue-like vascularised liver organoids from human PSCs.

A lack of physiological parity between 2D cell culture and in vivo, has paved the way towards more organotypic models. Organoids exist for a number of tissues, including the liver. However, current approaches to generate hepatic organoids suffer drawbacks, including a reliance on extracellular matrices (ECM), the requirement to pattern in 2D culture, costly growth factors and a lack of cellular diversity, structure and organisation. Current hepatic organoid models are generally simplistic, composed of hepatocytes or cholangiocytes, which renders them less physiologically relevant when compared to native tissue. Here we aim to address these drawbacks. To address this, we have developed an approach that does not require 2D patterning, is ECM independent combined with small molecules to mimic embryonic liver development that produces massive quantities of liver like organoids. Using single-cell RNA sequencing and immunofluorescence we demonstrate a liver-like cellular repertoire, a higher order cellular complexity, presenting with vascular luminal structures, innervation and a population of resident macrophage - the Kupffer cells. The organoids exhibit key liver functions including drug metabolism, serum protein production, coagulation factor production, bilirubin uptake and urea synthesis. The organoids can be transplanted and maintained in mice producing human albumin long term. The organoids exhibit a complex cellular repertoire reflective of the organ, have de novo vascularization and innervation, enhanced function and maturity. This is a pre-requisite for a myriad of applications from cellular therapy, tissue engineering, drug toxicity assessment, disease modeling, to basic developmental biology.

cell biology↗