The aim of project P02 is to generate a representative model of human pancreatic ductal adenocarcinoma (PDAC) in pigs. This will be a unique resource for researchers studying many aspects of the disease, providing a new means of validating research findings gained in vitro and in small animal studies, and facilitating the translation of new advances into benefit for patients. Pigs have advantages for preclinical studies as they share many similarities with humans in body size, anatomy, diet and their physiological and pathophysiological responses. They are relatively long lived, which allows longitudinal studies to be carried out in individual animals under conditions that mimic the human patient. For these reasons pigs are already used in biomedical research, and their value is considerably increased by the engineering of precise genetic modifications that replicate lesions responsible for human disease conditions. The production of genetically modified pigs can be significantly streamlined via the use of gene editing enzymes.

The opportunity to replicate PDAC in pigs was made possible by the development of a mouse model based on pancreas-specific expression of mutant KrasG12D and Trp53R172H. This results in a disease phenotype that resembles human PDAC. Using the same approach, we have now generated pig lines with Cre-inducible TP53R167H (orthologous to mouse Trp53R172H and human TP53R175H) and KRASG12D mutations engineered in the endogenous genes. We have also generated animals carrying a fluorescence-based reporter system that directly visualises cells that have undergone Cre-mediated gene activation. The next steps are to activate mutant KRASG12D and TP53R167H expression specifically in the porcine pancreas, then characterise the model by cross-species comparison of the porcine pathophenotype with that in mice and humans. We will then further optimise and modify the model to maximise its value for translational studies. This involves developing a system of cultured pancreatic organoids for in vitro analysis to supplement animal work. We will also establish a platform based on CRISPR/Cas9 components that will facilitate efficient systematic cell-specific mutagenesis of PDAC-related genes and gene combinations in somatic cells in vivo and in culture.