Establishment of new human and mouse liver cancer models and their use to uncover the role of RNF43 and ZNRF3 in liver homeostasis and repair

Primary liver cancer (PLC) is the second most common cause of cancer death worldwide, preceded only by lung cancer. Current models for PLC either fail to fully recapitulate tumour histology and architecture or are expensive, time consuming and do not allow for personalised drug testing. During the first part of my PhD, I have collaborated with Dr. Laura Broutier in order to established a new 3D in vitro model system for liver cancer. Based on the current knowledge on organoid cultures, we have managed to establish a system to grow primary human liver cancer cells long-term (Broutier et al., in press). Interestingly, the tumour-derived organoids (tumoroids) recapitulate the original tumour histology and genetic alterations and are also able to generate tumours in an in vivo xenograft mouse model after long-term expansion. Furthermore, we have shown that tumoroids can also be successfully used for drug testing, suggesting their use to devise new targeted therapy as well as personalised treatment strategies. Current models to investigate the role of genes in cancer rely mostly on animal studies, which can be very time consuming and cost demanding, especially if resulting in negative outcomes. To overcome this issue, I have set up a protocol for introducing mutations in healthy human liver organoids using the CRISPR-Cas9 technology. Interestingly, after mutating TP53, RNF43 and ZNRF3 either alone or in combination, human organoids undergo genetic alterations and phenotypic changes that partially resemble the ones observed in tumoroids. This data suggests that this system could be used as a screening platform to study gene function before using animal models. In the last part, I have further explored the role of RNF43 and ZNRF3 (R&Z) - two newly identified WNT pathway negative regulators mutated in many cancer types - in the liver using an in vivo mouse model. Interestingly, conditional deletion of R&Z specifically in adult mouse hepatocytes results metabolic changes that eventually lead to extensive liver damage. However, when the liver is challenged to regenerate in a chronic damage model, R&Z mutated livers fail to fully repair and show presence of multiple regenerative nodules. Later, livers develop either focal nodular hyperplasia and/or early hepatocellular carcinoma. These data suggest that R&Z have an important role in both liver metabolic homeostasis and liver regeneration and that their alteration can eventually lead to cancer formation.

Name dc:type.qualificationname

Doctor of Philosophy (PhD)

Level dc:type.qualificationlevel

Doctoral

Grantor dc:publisher.institution

University of Cambridge

Year dc:date.issued

2018

Author dc:creator

• Mastrogiovanni, Gianmarco

Advisors dc:contributor.advisor

• Koo, Bon-Kyoung
• Huch, Meritxell

• Rnf43
• Znrf3
• Liver cancer model
• liver
• crispr
• organoids
• tumoroids

Licence

• https://apollo8-f-pro.lib.cam.ac.uk/bitstreams/a7e83ae9-5267-4e9d-b22d-d5b8e81c5f19/download
• https://www.rioxx.net/licenses/all-rights-reserved/

Language dc:language

en

DOI dc:identifier.doi

https://doi.org/10.17863/CAM.20368

OAI identifier oai:identifier

oai:www.repository.cam.ac.uk:1810/273341