Peng group

Group leader: Dr. Weng Chuan Peng

Understanding childhood liver cancer

Pediatric liver cancer is a rare cancer that affects approximately 1 in a million children. In the Netherlands, about 8 – 10 children are diagnosed with liver cancer every year. The most common malignant liver tumors in children are hepatoblastoma (HB) and hepatocelullar carcinoma (HCC). Histologically, hepatoblastoma can generally be classified into various subtypes such as pure fetal (well differentiated, crowded), embryonal (less differentiated, more aggressive), small-cell undifferentiated (very aggressive), while HCCs oberved in children and adolescents are pathologically and biologically distinct from HCC in adults.  Due to the limited number of patients, childhood liver cancer is poorly studied.

"Finding the unknown unknowns" Weng Chuan Peng - Group leader

We will investigate the biology underlying liver cancer, based on NGS data (WGS/WES, single cell RNA-seq, spatially-resolved transcriptomics etc), in vitro organoid model derived from tumor cells (gene editing, advanced imaging, high throughput screening), and in vivo mouse model (tumor cells, organoid transplantion in the liver). The overall aim is to unravel the genetic basis of tumor variants, identify key signaling pathways, the role of tumor microenviroment, and characterization of the immune profile. One of our immediate goal is to establish a patient-derived tumor organoid biobank. These ‘tumoroids’ will be the basis for personalized medicines, for e.g., genomic analysis, drug screening, and predicting responses to chemotherapy, among others. With the knowledge gained from basic research, we aim to answer clinically relevant questions; for instance, why are some tumor subtypes more aggresive than others and respond poorly to chemotherapy. In addition, we hope to find novel biomarkers for tracking tumor responses to chemotherapy and identify potential therapeutics (e.g., antibodies, engineered ligands) targeting tumor subtypes that are difficult to treat.

At the Maxima, we will be working closely with the clinicians (i.e., pediatric oncologist, pathologist, surgeon) to understand childhood liver cancer. Through the understanding of tumor biology, we hope to find novel strategies to treat liver cancer, expose fewer children to chemotherapy, and ultimately cure more children without compromising their quality of life.

Adult stem cell 3D culture and cell replacement therapy

Establishing engraftable hepatocyte organoids (‘mini liver on a dish’):

A long-standing challenge in the stem cell field is the ability to expand primary cell type indefinitely in vitro, while maintaining its physiological properties. This is exacerbated by the fact that many tissues are slow cycling, for example, the liver, lung, kidney, pancreas, heart, showing little-to-no proliferation in vivo.

Our lab utilizes the liver as our model organ due to its immense regenerative capacity following injury. Recently, we demonstrated that murine hepatocytes can be propagated indefinitely in 3D culture, by incorporating factors that are typically observed during tissue repair. Of particular significance is that these in vitro- expanded progenitor cells could engraft efficiently in the injured livers of FAH mice and expressed the appropriate markers related to liver function  (Peng et al., Cell, 2018).

The ability to generate large number of healthy cells is the first essential step towards making cell replacement therapy (to treat liver diseases) possible. It is estimated that 5 – 10% of engraftment is sufficient to maintain normal liver function. We are currently focusing on expanding functional adult human hepatocytes indefinitely in vitro, and develop strategies to (i) achieve significant engraftment, and more importantly (ii) maintain their long-term engraftment in mouse model; Our long-term goal is that cell transplantation may one day address the issue of organ donor shortage.

We are always looking for students from diverse backgrounds (molecular biology, engineering, computational etc),  who are passionate in science and problem-solving to join our lab.

Key publications:

Liver, organoid technology, regenerative medicine, cell transplantation, transcriptomic profiling

Kluiver TA, Kraaier LJ, Peng WC*. Long-Term Expansion of Primary Hepatocyte Organoids. A detailed protocol for murine hepatocyte organoid culture, to be published in the lab protocol series “Hepatocytes” in Methods in Molecular Biology (available upon request).

Peng WC*, Kraaier LJ, Kluiver TA. Hepatocyte organoids and cell transplantation: What the future holds. Exp Mol Med. 2021 Oct 18. doi: 10.1038/s12276-021-00579-x. Epub ahead of print. PMID: 34663941.

Marsee A, Roos FJM, Verstegen MMA; HPB Organoid Consortium, Gehart H, de Koning E, Lemaigre F, Forbes SJ, Peng WC, Huch M, Takebe T, Vallier L, Clevers H, van der Laan LJW, Spee B. Building consensus on definition and nomenclature of hepatic, pancreatic, and biliary organoids. Cell Stem Cell. 2021 May 6;28(5):816-832. doi: 10.1016/j.stem.2021.04.005. PMID: 33961769.

Miao Y, et al. Next-Generation Surrogate Wnts Support Organoid Growth and Deconvolute Frizzled Pleiotropy In Vivo. Cell Stem Cell. 2020 Nov 5;27(5):840-851.e6. doi: 10.1016/j.stem.2020.07.020. Epub 2020 Aug 19. PMID: 32818433; PMCID: PMC7655723.

Peng WC*, Logan CY, Fish M, Anbarchian T, Aguisanda F, Alvarez A, Wu P, Jin Y, Zhu J, Li B, Grompe M, Wang B, Nusse R*.  2018) Inflammatory cytokine TNFa promotes the long-term expansion of primary hepatocytes in 3D culture. Cell 175,  607–1619.e1615. (* corresponding authors, Featured in F1000 Faculty Recommendation).

• In this landmark study, we established the first murine hepatocyte organoid culture by employing tissue regenerative signals in the liver. More importantly, we demonstrated that these organoids are very efficient in engraftment, with up to 80% repopulation after transplantation in a mouse liver injury model. As a result, the donor cells support and maintain liver function when the host liver function is impaired. This study, and other studies, paved way for the use of lab grown organoids to treat various metabolic liver diseases.

Tabula Muris Consortium. A single-cell transcriptomic atlas characterizes ageing tissues in the mouse. Nature Publishing Group. Nature Publishing Group; 2020 Jul 15;153:1194–6.

Schaum N, Lehallier B, Hahn O, Pálovics R, Hosseinzadeh S, Lee SE, Sit R, Lee DP, Losada PM, Zardeneta ME, Fehlmann T, Webber JT, McGeever A, Calcuttawala K, Zhang H, Berdnik D, Mathur V, Tan W, Zee A, Tan M, Tabula Muris Consortium, Pisco AO, Karkanias J, Neff NF, Keller A, Darmanis S, Quake SR, Wyss-Coray T. Ageing hallmarks exhibit organ-specific temporal signatures. Nature Publishing Group. Nature Publishing Group; 2020 Jul 15;153:1194–7.

Tabula Muris Consortium. Single-cell transcriptomics of 20 mouse organs creates a Tabula Muris. Nature Publishing Group. 1st ed. Nature Publishing Group; 2018 Oct 3;562(7727):367–72.

• In the above studies, we performed single cell transcriptomic profiling of liver tissues for the mouse cell atlas project, which aim to study aging processes. Tabula Muris Consortium is a collaborative project between Stanford University, UCSF and the Chan Zuckerberg Initiative (CZI) Biohub.

Structural biology, Wnt signaling, membrane proteins

de Lau W, Peng WC, Gros P, Clevers H (2014) The R-spondin/Lgr5/Rnf43 module: regulator of Wnt signal strength. Genes & development 28(4): 305–16.

Peng WC*, de Lau W*, Forneris F, Granneman JCM, Huch M, Clevers H, Gros P (2013) Structure of Stem Cell Growth Factor R-spondin 1 in Complex with the Ectodomain of Its Receptor LGR5.  Cell Reports 3(6): 1885–1892.  *co-first authors

Peng WC, de Lau W, Madoori PK, Forneris F, Granneman JCM, Clevers H, Gros P (2013) Structures of Wnt-antagonist ZNRF3 and its complex with R-spondin 1 and implications for signaling. PLoS ONE 8(12): e83110.

• In the above studies (and review), we used x-ray crystallography to unravel the molecular mechanism of Wnt signaling regulation by LGR5, R-spondin and ZNRF3. The surface receptors LGR5 and ZNRF3 are typically expressed in progenitors/stem cells in multiple adult epithelial tissues. Binding of R-spondin to LGR5 and ZNRF3 permits adult stem cell proliferation. This project was performed in close collaboration with the Clevers lab.

Peng WC, Lin X, Torres J (2009) The strong dimerization of the transmembrane domain of the fibroblast growth factor  receptor 3 (FGFR3) is modulated by C-terminal juxtamembrane residues. Protein Science 18: 450–459.

• In this study, we used infrared spectroscopy to study the structure of FGFR3 transmembrane peptide in lipid bilayers and to probe the effect of mutations that have been shown to cause dwarfism. This study project was conceived and initiated when I was a research assistant in the Torres lab.

Priya R, Tadwal, VS, Roessle MW, Gayen S, Hunke C, Peng WC, Torres J, Grüber G (2008) Low resolution structure of  subunit b (b (22-156)) of Escherichia coli F(1)F(O) ATP synthase in solution and the b-delta assembly.  Journal of Bioenergetics and Biomembranes 40: 245–255.