Biology subjects

Bikfalvi, A.

Publications and source records attributed to Bikfalvi, A..

6 recordsLinked to original sources

bioRxiv2025

A versatile microfluidic extrusion-based hydrogel platform for self-organization and long-term maintenance of engineered 3D lymphatic endothelium

Lymphatic endothelium is essential for interstitial fluid drainage, immune surveillance, and macromolecular transport. Existing in vitro models that accurately recapitulate its three-dimensional structure, barrier properties, and long-term stability are still limited. In this study, we propose a robust, adaptable, and scalable platform designed to generate engineered three-dimensional lymphatic endothelium using primary human dermal lymphatic endothelial cells (HDLECs). This system combines microfluidic extrusion-based fabrication allowing precise control of the tubular geometry with custom-optimized extracellular matrix-derived hydrogel. The capability to tune dimensions enables the creation of constructs that encompass physiologically relevant size ranges. Through a systematic matrix screen, we identified a unique four-component formulation--gelatin, Matrigel, hyaluronic acid, and fibrinogen--that supports the rapid self-assembly of HDLECs into stable, lumen-forming monolayers within one week. These engineered structures maintain viability and structural integrity for a minimum of 30 days under static culture conditions. Functional permeability assays demonstrated selective tracer uptake characteristics of lymphatic transport. Comparative studies with blood vascular endothelial cells indicate that the proposed platform preserves maintenance of lineage-specific expression profiles, junctional organization, and permeability properties under identical fabrication parameters. Altogether, this approach offers a reproducible and controlled system for studying three-dimensional endothelial architecture, transport mechanisms, and extracellular matrix remodeling across diverse endothelial phenotypes, thereby addressing a pivotal gap in the modeling of lymphatic vasculature. HighlightsO_LIA microfluidic extrusion platform allows primary human lymphatic endothelial cells to self-organize into 3D hollow tubes. C_LIO_LIThe internal dimensions of the hybrid cell/hydrogel constructs can be precisely controlled by tuning the flow rates. C_LIO_LIA custom-defined four-component extracellular matrix provides essential biochemical cues for stable monolayer formation and for the in vitro organization of lymphatic endothelial vessels. C_LIO_LIMatrix composition significantly influences cell proliferation and migration, thereby impacting on the spatial arrangement of the tissue. C_LIO_LIThe three-dimensional lymphatic tissue configuration sustains cell viability, consistent expression of lineage-specific markers, and barrier function which lasts for at least 30 days. C_LIO_LIThe system maintains morphological and functional properties not only for lymphatic endothelial cells, but also for blood endothelial cells in long-term culture conditions. C_LI

bioengineering↗

bioRxiv2024

Exploiting a metabolic vulnerability in brain tumour stem cells using a brain-penetrant drug with safe profile

Glioblastoma (GB) remains one of the most treatment refractory and fatal tumour in humans. GB contains a population of self-renewing stem cells, the brain tumour stem cells (BTSC) that are highly resistant to therapy and are at the origin of tumour relapse. Here, we report, for the first time, that mubritinib potently impairs stemness and growth of patient-derived BTSCs harboring different oncogenic mutations. Mechanistically, by employing bioenergetic assays and rescue experiments, we provide compelling evidence that mubritinib acts on complex I of the electron transport chain to impair BTSC stemness pathways, self-renewal and proliferation. Global gene expression profiling revealed that mubritinib alters the proliferative, neural-progenitor-like, and the cell-cycling state signatures. We employed in vivo pharmacokinetic assays to establish that mubritinib crosses the blood-brain barrier. Using preclinical models of patient-derived and syngeneic murine orthotopic xenografts, we demonstrated that mubritinib delays GB tumourigenesis, and expands lifespan of animals. Interestingly, its combination with radiotherapy offers survival advantage to animals. Strikingly, thorough toxicological and behavioral studies in mice revealed that mubritinib does not induce any damage to normal cells and has a well-tolerated and safe profile. Our work warrants further exploration of this drug in in-human clinical trials for better management of GB tumours.

cancer biology↗

bioRxiv2022

Shadow imaging for panoptical visualisation of living brain tissue

Progress in neuroscience research hinges on technical advances in visualizing living brain tissue with high fidelity and facility. Current neuroanatomical imaging approaches either require tissue fixation, do not have cellular resolution or only give a fragmented view. Here, we show how regular light microscopy together with fluorescence labeling of the interstitial fluid in the extracellular space provide comprehensive optical access in real-time to the anatomical complexity and dynamics of living brain tissue.

neuroscience↗

bioRxiv2021

SLIT2-ROBO signaling in tumor-associated microglia/macrophages drives glioblastoma immunosuppression and vascular dysmorphia

SLIT2 is a secreted polypeptide that guides migration of cells expressing ROBO1&2 receptors. Herein, we investigated SLIT2/ROBO signaling effects in gliomas. In patients with glioblastoma (GBM), SLIT2 expression increased with malignant progression and correlated with poor survival and immunosuppression. Knockdown of SLIT2 in mouse glioma cells and patient derived GBM xenografts reduced tumor growth and synergized with immunotherapy to prolong survival. Tumor cell SLIT2 knockdown inhibited macrophage invasion and promoted a cytotoxic gene expression profile, which improved tumor vessel function and enhanced efficacy of chemotherapy and immunotherapy. Mechanistically, SLIT2 promoted microglia/macrophage chemotaxis and tumor-supportive polarization via ROBO1&2-mediated PI3K{gamma} activation. Macrophage Robo1&2 deletion and systemic SLIT2 trap delivery mimicked SLIT2 knockdown effects on tumor growth and the tumor microenvironment (TME), revealing SLIT2 signaling through macrophage ROBOs as a novel regulator of the GBM microenvironment and a potential immunotherapeutic target for brain tumors.

cancer biology↗

bioRxiv2021

TGF-beta promotes microtube formation in glioblastoma through Thrombospondin 1

Microtubes (MTs), cytoplasmic extensions of glioma cells, are important cell communication structures promoting invasion and treatment resistance through network formation. MTs are abundant in chemoresistant gliomas, in particular glioblastomas (GBMs), while they are uncommon in chemosensitive IDH-mutant and 1p/19q co-deleted oligodendrogliomas. To identify potential signaling pathways involved in MT formation we performed a bioinformatics analysis of TCGA data showing that the TGF-{beta} pathway is highly activated in GBMs compared to oligodendroglial tumors. In particular we observed that signaling pathways involved in extracellular matrix organization are differentially expressed between these tumor entities. Using patient-derived GBM stem cell lines, we demonstrated that TGF-{beta}1 stimulation promotes enhanced MT formation and communication via Calcium signaling. Inhibition of the TGF-{beta} pathway significantly reduced MT formation and its associated invasion in vitro and in vivo. Downstream of TGF-{beta}, we identified thrombospondin 1 (TSP1) as a potential mediator of MT formation in GBM through SMAD activation. TSP1 was upregulated upon TGF-{beta} stimulation and enhanced MT formation, which was inhibited by TSP1 shRNAs in vitro and in vivo. In conclusion, TGF-{beta} and its downstream mediator TSP1 are important mediators of the MT network in GBM and blocking this pathway could potentially help to break the complex MT driven invasion/ resistance network.

cancer biology↗

bioRxiv2020

A multi-layered systems approach for renal cell carcinoma

Renal cell carcinoma (RCC) still lacks prognostic and predictive biomarkers to monitor the disease and the response to therapy. The usual strategy in translational research is to start from human samples, to identify molecular markers and gene networks and then to functionally validate them in vitro and in animal models. We devised herein a completely opposite strategy from "mouse to man" by performing an aggressiveness screen and used functional genomics, imaging, clinical data and computational approaches in order to discover molecular pathways and players in renal cancer development and metastasis. Multiple cell lines for primary tumor growth, survival in the blood circulation and lung metastasis or metastatic spread from the primary tumor were generated and analyzed using a multi-layered approach which includes large-scale transcriptome, genome and methylome analyses. Transcriptome and methylome analyses demonstrated distinct clustering in three different groups. Remarkably, DNA sequencing did not show significant genomic variations in the different groups which indicates absence of clonal selection during the in vivo amplification process. Transcriptome analysis revealed distinct signatures of tumor aggressiveness which were validated in patient cohorts. Methylome analysis of full-length DNA allowed clustering of the same groups and revealed clinically relevant signatures. Furthermore, we identified SAA2 and CFB as soluble prognostic and predictive biomarkers of the therapeutic response. We also uncovered IL34 as another soluble prognostic biomarker and key regulator of renal cell carcinoma (RCC) progression. This was also functionally validated in vivo, and a mathematical model of IL34-dependent primary tumor growth and metastasis development was provided. These results indicate that such multilayered analysis in a RCC animal model leads to meaningful results that are of translational significance. One Sentence SummaryAn aggressiveness screen with multilayer systems analysis to identify signatures and biomarkers for renal cell carcinoma aggressiveness.

cancer biology↗