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Biology subjects

Verstegen, M. M. A.

Publications and source records attributed to Verstegen, M. M. A..

3 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↗

Integrin-TGFβ axis induces partial EMT in basal-like cells to lead collective invasion

Collective invasion is the predominant mode of cancer cell dissemination in breast cancer and represents the initial step of metastatic spread. Basal-like leader cells drive this process by maintaining cell-cell junctions with the follower cells while extending actin-rich protrusions and remodeling the collagen I-rich peritumoral stroma. These features resemble those of individually-invading cells following epithelial-to-mesenchymal transition (EMT). However, how leader cells acquire these traits while preserving cohesion within the collective remains unclear. Here, we identify a collagen I-responsive subset of basal-like cells that coexpress cytoskeletal, extracellular matrix (ECM)-remodeling, and epithelial junction genes. We show that integrin 2 (Itg2) links collagen I engagement to mesenchymal reprogramming by inducing inhibin beta A (INHBA) expression and activating tumor growth factor {beta} (TGF{beta}) signaling. This, in turn, upregulates vimentin while preserving epithelial junction gene expression. In parallel, Itg2 promotes ECM degradation through a TGF{beta}-independent mechanism. This study identifies Itg2-TGF{beta} axis as a key regulator of partial EMT and leader cell function, highlighting it as a potential therapeutic target in aggressive breast cancers.

cell biology↗

Human liver organoids; a patient-derived primary model for HBV Infection and Related Hepatocellular Carcinoma

The molecular events that drive Hepatitis B virus (HBV)-mediated transformation and tumorigenesis have remained largely unclear, due to the absence of a relevant primary model system. Here we propose the use of human liver organoids as a platform for modeling HBV infection and related tumorigenesis. We first describe a primary ex vivo HBV-infection model derived from healthy donor liver organoids after challenge with recombinant virus or HBV-infected patient serum. HBV infected organoids produced cccDNA, expressed intracellular HBV RNA and proteins, and produced infectious HBV. This ex vivo HBV infected primary differentiated hepatocyte organoid platform was amenable to drug screening for both anti-HBV activity as well as for drug-induced toxicity. We also studied HBV replication in transgenically modified organoids; liver organoids exogenously overexpressing the HBV receptor NTCP by lentiviral transduction were not more susceptible to HBV, suggesting the necessity for additional host factors for efficient infection. We also generated transgenic organoids harboring integrated HBV, representing a long-term culture system also suitable for viral production and the study of HBV transcription. Finally, we generated HBV-infected patient-derived liver organoids from non-tumor cirrhotic tissue of explants from liver transplant patients. Interestingly, transcriptomic analysis of patient-derived liver organoids indicated the presence of an aberrant early cancer gene signature, which clustered with the HCC cohort on the TCGA LIHC dataset and away from healthy liver tissue, and may provide invaluable novel biomarkers for disease surveillance and development of HCC in HBV infected patients.

cancer biology↗