Organotypic Culture of Acinar Cells for the Study of Pancreatic Cancer Initiation

Simple Summary Pancreatic Cancer is a deadly disease, with a dismal prognosis. A better understanding of the molecular alterations that cause the malignant transformation of pancreatic epithelial cells is pivotal to curtail disease incidence and detect the disease early when it can be surgically resected. The culture of pancreatic pre-malignant cells is technically challenging, but a great tool for the study of tumor evolution and early oncogenic alterations. Here, we will describe the isolation of pancreatic acinar cells and its value for the study of tumor initiation, from a technical and historical perspective. The carcinogenesis of pancreatic ductal adenocarcinoma (PDA) progresses according to multi-step evolution, whereby the disease acquires increasingly aggressive pathological features. On the other hand, disease inception is poorly investigated. Decoding the cascade of events that leads to oncogenic transformation is crucial to design strategies for early diagnosis as well as to tackle tumor onset. Lineage-tracing experiments demonstrated that pancreatic cancerous lesions originate from acinar cells, a highly specialized cell type in the pancreatic epithelium. Primary acinar cells can survive in vitro as organoid-like 3D spheroids, which can transdifferentiate into cells with a clear ductal morphology in response to different cell- and non-cell-autonomous stimuli. This event, termed acinar-to-ductal metaplasia, recapitulates the histological and molecular features of disease initiation. Here, we will discuss the isolation and culture of primary pancreatic acinar cells, providing a historical and technical perspective. The impact of pancreatic cancer research will also be debated. In particular, we will dissect the roles of transcriptional, epigenetic, and metabolic reprogramming for tumor initiation and we will show how that can be modeled using ex vivo acinar cell cultures. Finally, mechanisms of PDA initiation described using organotypical cultures will be reviewed.