Ras/MAPK signalling intensity defines subclonal fitness in a mouse model of hepatocellular carcinoma
Abstract
Quantitative differences in signal transduction are to date an understudied feature of tumour heterogeneity. The MAPK Erk pathway, which is activated in a large proportion of human tumours, is a prototypic example of distinct cell fates being driven by signal intensity. We have used primary hepatocyte precursors transformed with different dosages of an oncogenic form of Ras to model subclonal variations in MAPK signalling. Orthotopic allografts of Ras-transformed cells in immunocompromised mice gave rise to fast-growing aggressive tumours, both at the primary location and in the peritoneal cavity. Fluorescent labelling of cells expressing different oncogene levels, and consequently varying levels of MAPK Erk activation, highlighted the selection processes operating at the two sites of tumour growth. Indeed, significantly higher Ras expression was observed in primary as compared to secondary, metastatic sites, despite the apparent evolutionary trade-off of increased apoptotic death in the liver that correlated with high Ras dosage. Analysis of the immune tumour microenvironment at the two locations suggests that fast peritoneal tumour growth in the immunocompromised setting is abrogated in immunocompetent animals due to efficient antigen presentation by peritoneal dendritic cells. Furthermore, our data indicate that, in contrast to the metastatic-like outgrowth, strong MAPK signalling is required in the primary liver tumours to resist elimination by NK cells. Overall, this study describes a quantitative aspect of tumour heterogeneity and points to a potential vulnerability of a subtype of hepatocellular carcinoma as a function of MAPK Erk signalling intensity.
Data availability
The RNA-sequencing data have been deposited in the Gene Expression Omnibus (GEO, NCBI) repository, and are accessible through GEO Series accession number GSE180580. Raw data from figures 1 to 5 were deposited on Mendeley data at doi: 10.17632/73nbvs8925.1.
Article and author information
Author details
Funding
SIRIC Montpellier Cancer (Grant INCa_Inserm_DGOS_12553)
- Urszula Hibner
Grant HTE-ITMO Cancer (HTE201610)
- Urszula Hibner
Association Francaise pour l'Etude du Foie
- Damien Grégoire
Dutch Cancer Society (KWF 12049/2018-2)
- Leila Akkari
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All reported animal procedures were carried out in accordance with the rules of the FrenchInstitutional Animal Care and Use Committee and European Community Council(2010/63/EU). Animal studies were approved by institutional ethical committee (Comitéd'éthique en expérimentation animale Languedoc-Roussillon (#36)) and by the Ministère del'Enseignement Supérieur, de la Recherche et de l'Innovation (APAFIS#11196-2018090515538313v2).
Copyright
© 2023, Lozano et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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