The Missing Link: Cre Pigs for Cancer Research.

Daniela Kalla,Barbara Kessler,Mayuko Kurome,Heiko Lickert,Laura Beltran Sangüesa,Krzysztof Flisikowski,Kaiyuan Yang,Valeri Zakhartchenko,Tatiana Flisikowska,Eckhard Wolf,Angelika Schnieke,Dieter Saur

doi:10.3389/fonc.2021.755746

Abstract

The Cre/loxP system is a powerful tool for the generation of animal models with precise spatial and temporal gene expression. It has proven indispensable in the generation of cancer models with tissue specific expression of oncogenes or the inactivation of tumor suppressor genes. Consequently, Cre-transgenic mice have become an essential prerequisite in basic cancer research. While it is unlikely that pigs will ever replace mice in basic research they are already providing powerful complementary resources for translational studies. But, although conditionally targeted onco-pigs have been generated, no Cre-driver lines exist for any of the major human cancers. To model human pancreatic cancer in pigs, Cre-driver lines were generated by CRISPR/Cas9-mediated insertion of codon-improved Cre (iCre) into the porcine PTF1A gene, thus guaranteeing tissue and cell type specific function which was proven using dual fluorescent reporter pigs. The method used can easily be adapted for the generation of other porcine Cre-driver lines, providing a missing tool for modeling human cancers in large animals.

Highlights

In recent decades, genetically modified mice have dominated basic and preclinical research into human cancer and many other diseases, largely because of the availability of murine ES cells and the technical ease of engineering interesting mutations
As the basic helix-loop-helix transcription factor PTF1A/p48 is critical for pancreatic cell fate it is essential that only one allele is targeted
To replicate the murine model targeted gene placement supported by CRISPR/Cas9 was carried out in primary porcine cells isolated from a male German Landrace pig

Summary

Introduction

Genetically modified mice have dominated basic and preclinical research into human cancer and many other diseases, largely because of the availability of murine ES cells and the technical ease of engineering interesting mutations. Mice and humans share many fundamental similarities, but dissimilar protein interactions, physiology, and anatomy can lead to different disease phenotypes from similar genetic lesions [3]. Pigs share many similarities with humans in body size, Cre Pigs for Cancer Research anatomy, and their physiological and pathophysiological responses and are playing an ever more important role in preclinical research. Many practical requirements necessary for the use of pigs as models of human cancer and cancer predisposition are in place. Unlike for mice, no cancer specific porcine Cre-driver lines are available

Methods

Results

Conclusion