Pancreatic STAT5 activation promotes KrasG12D- and inflammation- induced acinar-to-ductal metaplasia and pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) remains a highly lethal malignancy due to its predilection for late-stage presentation. Signal transducer and activator of transcription 5 (STAT5) is a transcription factor implicated in the progression of various cancer types. However, its functional role in KRAS-driven pancreatic tumorigenesis remains unclear. We found that high levels of STAT5 in tumor cells were associated with a poorer prognosis in patients. The loss of Stat5 in acinar cells significantly reduced the development of acinar-to-ductal metaplasia (ADM) and PDAC lesions driven by KRAS mutation and pancreatitis. IL-22 signaling, induced by chronic inflammation, enhanced KRAS-mutant mediated STAT5 phosphorylation and the tumor-promoting function of IL-22 depends on the activation of STAT5. Chromatin immunoprecipitation assays revealed that STAT5 was directly bound to the promoters of ADM mediators HNF4a. Overall design: Acinar cells from KC and KCS mouse pancreata tissues infected with Ad5-Cre or Ad5 to induce KRAS mutation were obtained for RNA-seq to analyze the role of STAT5 in PDAC development.