Mouse models for pancreatic ductal adenocarcinoma areaffected by the cre-driver used to promote KRASG12D activation

The fundamental biology of pancreatic ductal adenocarcinoma has been greatly impacted by the characterization of genetically engineered mouse models that allow temporal and spatial activation of oncogenic KRAS (KRASG12D). One of the most commonly used models involves targeted insertion of a cre-recombinase into the Ptf1a gene. However, this approach disrupts the Ptf1a gene, resulting in haploinsufficiency that likely affects sensitivity to oncogenic KRAS (KRASG12D). This study aims to determine if Ptf1a haploinsufficiency affected the acinar cell response to KRASG12D before and after induction of pancreatic injury. Taken together, our results suggest Ptf1a haploinsufficiency in Ptf1acreERT mouse models promotes KRASG12D priming of genes for promotion of PDAC. Overall design: We performed morphological and molecular analysis of three genetically engineered mouse models that express a tamoxifen-inducible cre-recombinase to activate KRASG12D in acinar cells of the pancreas. The cre-recombinase was targeted to the acinar-specific transcription factor genes, Ptf1a or Mist1/Bhlha15, or expressed within a BAC-derived Elastase transgene. Histological and RNA-seq analyses were used to delineate differences between the models