NOVEL MODEL TO STUDY PDAC USING NORMAL HUMAN PANCREATIC TISSUE
Novel model for studying PDAC using normal human pancreatic tissue For the past twenty years, the survival rate for many cancers has improved, but survival for pancreaticductal adenocarcinoma (PDAC) has not, due to lack of both early detection methods and effective treatments.Human PADC cancer cell lines have been widely used. However, such cell lines are far from original organtissue, and their highly unstable genome complicates interpretation. On the other hand, while animal modelsovercome many of the limitations of cell lines, genetically engineered mouse models (GEMMs) may overlooksome profound differences between human and mouse cells. Indeed, nearly 90% of drugs with proven efficacyin animal models are ineffective in clinical trials. In our previous studies, we have successfully induced ADM inprimary human normal acinar cells and found distinct features of human cells. We further engineered theseacinar-derived ductal like (AD) cells to PDAC cells by specifically introducing the landscape mutationcombination (KRAS/P16/TP53/SMAD4, KPTS) of human PDAC. Importantly, when transplanted into mice,these genetically engineered cells gave rise to invasive desmoplastic tumors, recapitulating the clinicalfeatures of PDAC in human patients, highlighting the power of this novel system to modeling human PDACdevelopment. Given the fact that PDAC gains mutations during progression, we propose to use our novelsystem to generate engineered cells carrying fewer mutations, which may give rise to non-invasive neoplasiawhen orthotropically transplanted into NOD-SCID mice. This model will not only help us to understand themechanisms of human PDAC development, it may also be a valuable platform to identify biomarkers for earlydiagnosis. Since our engineered AD cells give rise to tumors recapitulating clinical features of human PDAC,they are a good model to identify key targets to stop the growth of fully established tumors in vivo. To test thisconcept, we will utilize an inducible gRNA expressing vector to specifically knockout oncogenic KRAS in vivo toinduce tumor size reduction. Success with this method would provide a powerful model to identify otheressential genes supporting human PDAC progression and to reveal possible pathways for human PDACrelapse after KRAS knockout. The proposed novel models have great clinical potential on precision medicine,identification of early diagnosis methods, and development of new treatment strategies for human PDAC.