generation-of-functional-endodermal-hepatic-organoids

Generation of Functional Endodermal Hepatic Organoids

Organoid technology has allowed us to generate a variety of human organ-like mini structures, such as for the liver, brain, and intestine, in vitro. The ...

Izmir Biomedicine and Genome Center

Dokuz Eylul University

Izmir Tinaztepe University

Organoid technologies have become a powerful emerging tool to model liver diseases, for drug screening, and for personalized treatments. These applications are, however, limited in their capacity to generate functional hepatocytes in a reproducible and efficient manner. Here, we generated and characterized the hepatic organoid (eHEPO) culture system using human induced pluripotent stem cell (iPSC)-derived EpCAM-positive endodermal cells as an intermediate. eHEPOs can be produced within 2 weeks and expanded long term (>16 months) without any loss of differentiation capacity to mature hepatocytes. Starting from patient-specific iPSCs, we modeled citrullinemia type 1, a urea cycle disorder caused by mutations in the argininosuccinate synthetase (ASS1) enzyme. The disease-related ammonia accumulation phenotype in eHEPOs could be reversed by the overexpression of the wild-type ASS1 gene, which also indicated that this model is amenable to genetic manipulation. Thus, eHEPOs are excellent unlimited cell sources to generate functional hepatic organoids in a fast and efficient manner.

Robust, Long-Term Culture of Endoderm-Derived Hepatic Organoids for Disease Modeling.

The complex and heterogeneous nature of hepatocellular carcinoma (HCC) hampers the identification of effective therapeutic strategies. Cancer stem cells (CSCs) represent a fraction of cells within tumors with the ability to self-renew and differentiate, and thus significantly contribute to the formation and maintenance of heterogeneous tumor mass. Increasing evidence indicates high plasticity in tumor cells, suggesting that non-CSCs could acquire stem cell properties through de-differentiation or reprogramming processes. In this paper, we reveal KLF4 as a transcription factor that can induce a CSC-like phenotype in non-CSCs through upregulating the EpCAM and E-CAD expression. Our studies indicated that KLF4 could directly bind to the promoter of  and increase the number of EpCAM/CD133 liver cancer stem cells (LCSCs) in the HuH7 HCC cell line. When KLF4 was overexpressed in EpCAM/CD133 non-stem cells, the expressions of hepatic stem/progenitor cell genes such as ,  and  were significantly increased. KLF4 overexpressing non-stem cells exhibited greater cell viability upon sorafenib treatment, while the cell migration and invasion capabilities of these cells were suppressed. Importantly, we detected an increased membranous expression and colocalization of β-CAT, E-CAD and EpCAM in the KLF4-overexpressing EpCAM/CD133 non-stem cells, suggesting that this complex might be required for the cancer stem cell phenotype Moreover our in vivo xenograft studies demonstrated that with a KLF4 overexpression, EpCAM/CD133 non-stem cells attained an in vivo tumor forming ability comparable to EpCAM/CD133 LCSCs, and the tumor specimens from KLF4-overexpressing xenografts had increased levels of both the KLF4 and EpCAM proteins. Additionally, we identified a correlation between the KLF4 and EpCAM protein expressions in human HCC tissues independent of the tumor stage and differentiation status. Collectively, our data suggest a novel function for KLF4 in modulating the de-differentiation of tumor cells and the induction of EpCAM/CD133 LCSCs in HuH7 HCC cells.

A Novel Function for KLF4 in Modulating the De-differentiation of EpCAM/CD133 nonStem Cells into EpCAM/CD133 Liver Cancer Stem Cells in HCC Cell Line HuH7.

The transfer and widespread acceptance of laser-induced thermal therapy into gastroenterology remain a topic of interest. However, a practical approach to the quantitative effect of photothermal injury in the esophagus needs further investigation. Here, we aim to perform computer simulations that simulate laser scanning and calculate the laser-induced thermal damage area. The simulation engine offers the results in a guide map for laser coagulation with a well-confined therapeutic area according to laser irradiance and surface scanning speed. The study also presents validation experiments that include histology analyses in an ex vivo sheep esophagus model.

Guide mapping for effective superficial photothermal coagulation of the esophagus using computer simulations with ex vivo sheep model validation study.

The aim of this study was to investigate the effects of pioglitazone on reactive oxygen species (ROS), expressions/activities of MMPs and TIMP-2, and VSMC proliferation and vascular reactivity in high glucose (HG)-induced human saphenous vein (HSV) grafts.

Article	Year
Robust, Long-Term Culture of Endoderm-Derived Hepatic Organoids for Disease Modeling. Stem cell reports\| PubMed ID: 31522975	2019
A Novel Function for KLF4 in Modulating the De-differentiation of EpCAM/CD133 nonStem Cells into EpCAM/CD133 Liver Cancer Stem Cells in HCC Cell Line HuH7. Cells\| PubMed ID: 32408542	2020
Guide mapping for effective superficial photothermal coagulation of the esophagus using computer simulations with ex vivo sheep model validation study. Lasers in surgery and medicine\| PubMed ID: 36047422	2022
Pioglitazone inhibits oxidative stress, MMP-mediated inflammation and vascular dysfunction in high glucose-induced human saphenous vein grafts. Journal of diabetes and its complications\| PubMed ID: 36905721	2023

Nevin Ersoy

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