Robin Loesch1, Stefano Caruso2, Valérie Paradis3, Cecile Godard1, Angélique Gougelet1, Gilles Renault4, Simon Picard1, Ingrid Tanaka1, Yoan Renoux-Martin1, Christine Perret5, Makoto Mark Taketo6, Jessica Zucman-Rossi2, Sabine Colnot7. 1. INSERM, Sorbonne Université, Université de Paris, Centre de Recherche des Cordeliers (CRC), F-75006, France; Equipe Labellisée Ligue Nationale Contre le Cancer, France. 2. INSERM, Sorbonne Université, Université de Paris, Centre de Recherche des Cordeliers (CRC), F-75006, France. 3. INSERM, Hôpital Beaujon, Clichy, France. 4. INSERM, CNRS, Institut COCHIN, F-75014, France; Plateforme Imageries du Vivant, Université de Paris, France. 5. INSERM, CNRS, Institut COCHIN, F-75014, France. 6. Colon Cancer Project, Kyoto University Hospital-iACT, Kyoto, Japan. 7. INSERM, Sorbonne Université, Université de Paris, Centre de Recherche des Cordeliers (CRC), F-75006, France; Equipe Labellisée Ligue Nationale Contre le Cancer, France. Electronic address: sabine.colnot@inserm.fr.
Abstract
BACKGROUND & AIMS: One-third of hepatocellular carcinomas (HCCs) harbor mutations activating the β-catenin pathway, predominantly via mutations in the CTNNB1 gene itself. Mouse models of Apc loss-of-function are widely used to mimic β-catenin-dependent tumorigenesis. Given the low prevalence of APC mutations in human HCCs, we aimed to generate liver tumors through CTNNB1 exon 3 deletion (βcatΔex3). We then compared βcatΔex3 liver tumors with liver tumors generated via frameshift in exon 15 of Apc (Apcfs-ex15). METHODS: We used hepatocyte-specific and inducible mouse models generated through either a Cre-Lox or a CRISPR/Cas9 approach using adeno-associated virus vectors. Tumors generated by the Cre-Lox models were phenotypically analyzed using immunohistochemistry and were selected for transcriptomic analysis by RNA-sequencing (RNAseq). Mouse RNAseq data were compared to human RNAseq data (8 normal tissues, 48 HCCs, 9 hepatoblastomas) in an integrative analysis. Tumors generated via CRISPR were analyzed using DNA sequencing and immuno-histochemistry. RESULTS: Mice with CTNNB1 exon 3 deletion in hepatocytes developed liver tumors indistinguishable from Apcfs-ex15 liver tumors. Both Apcfs-ex15 and βcatΔex3 mouse models induced growth of phenotypically distinct tumors (differentiated or undifferentiated). Integrative analysis of human and mouse tumors showed that differentiated mouse tumors cluster with well-differentiated human CTNNB1-mutated tumors. Conversely, undifferentiated mouse tumors cluster with human mesenchymal hepatoblastomas and harbor activated YAP signaling. CONCLUSION: Apcfs-ex15 and βcatΔex3 mouse models both induce growth of tumors that are transcriptionally similar to either well-differentiated and β-catenin-activated human HCCs or mesenchymal hepatoblastomas. LAY SUMMARY: New and easy-to-use transgenic mouse models of primary liver cancers have been generated, with mutations in the gene encoding beta-catenin, which are frequent in both adult and pediatric primary liver cancers. The mice develop both types of cancer, constituting a strong preclinical model.
BACKGROUND & AIMS: One-third of hepatocellular carcinomas (HCCs) harbor mutations activating the β-catenin pathway, predominantly via mutations in the CTNNB1 gene itself. Mouse models of Apc loss-of-function are widely used to mimic β-catenin-dependent tumorigenesis. Given the low prevalence of APC mutations in human HCCs, we aimed to generate liver tumors through CTNNB1 exon 3 deletion (βcatΔex3). We then compared βcatΔex3 liver tumors with liver tumors generated via frameshift in exon 15 of Apc (Apcfs-ex15). METHODS: We used hepatocyte-specific and inducible mouse models generated through either a Cre-Lox or a CRISPR/Cas9 approach using adeno-associated virus vectors. Tumors generated by the Cre-Lox models were phenotypically analyzed using immunohistochemistry and were selected for transcriptomic analysis by RNA-sequencing (RNAseq). Mouse RNAseq data were compared to human RNAseq data (8 normal tissues, 48 HCCs, 9 hepatoblastomas) in an integrative analysis. Tumors generated via CRISPR were analyzed using DNA sequencing and immuno-histochemistry. RESULTS: Mice with CTNNB1 exon 3 deletion in hepatocytes developed liver tumors indistinguishable from Apcfs-ex15 liver tumors. Both Apcfs-ex15 and βcatΔex3 mouse models induced growth of phenotypically distinct tumors (differentiated or undifferentiated). Integrative analysis of human and mouse tumors showed that differentiated mouse tumors cluster with well-differentiated human CTNNB1-mutated tumors. Conversely, undifferentiated mouse tumors cluster with human mesenchymal hepatoblastomas and harbor activated YAP signaling. CONCLUSION: Apcfs-ex15 and βcatΔex3 mouse models both induce growth of tumors that are transcriptionally similar to either well-differentiated and β-catenin-activated human HCCs or mesenchymal hepatoblastomas. LAY SUMMARY: New and easy-to-use transgenic mouse models of primary liver cancers have been generated, with mutations in the gene encoding beta-catenin, which are frequent in both adult and pediatric primary liver cancers. The mice develop both types of cancer, constituting a strong preclinical model.
Authors: Jésica Pérez-García; Abel Martel-Martel; Paula García-Vallés; Luis A Corchete; Juan L García; Nerea Gestoso-Uzal; Rosario Vidal-Tocino; Óscar Blanco; Lucía Méndez; Manuel Sánchez-Martín; Manuel Fuentes; Ana B Herrero; Andreana N Holowatyj; José Perea; Rogelio González-Sarmiento Journal: Cancers (Basel) Date: 2022-08-20 Impact factor: 6.575