Interleukin-1 upregulates dual oxidase 2 expression and ROS production in human pancreatic cancer cells in a STAT1/STAT3-dependent manner

Chronic pancreatitis and sustained pancreatic inflammation increase the risk of pancreatic ductal adenocarcinoma (PDAC), in part through the release of pro-inflammatory cytokines and excessive generation of reactive oxygen species (ROS). Interleukin-1 (IL-1), a major upstream cytokine secreted by malignant or microenvironmental cells, promotes pancreatic inflammation, tumorigenesis, invasiveness, and intratumoral heterogeneity. Previously, our laboratory has established that dual oxidase 2 (DUOX2), one of seven NADPH oxidase (NOX) family members, plays a critical role in H2O2-mediated host defense and chronic inflammation in the gastrointestinal tract. DUOX2 is upregulated and expressed along with its maturation factor, DUOXA2, in several human pancreatic cancer cell lines following exposure to various pro-inflammatory cytokines, including IFN-gamma, IL-4, and IL-17A. In the present study, we show that IL-1alpha and IL-1beta robustly upregulate DUOX2/DUOXA2 mRNA and protein expression in a panel of human PDAC cell lines and patient-derived PDAC organoids. IL-1 exposure triggers transient activation of STAT1 and STAT3, followed by sustained induction of DUOX2/DUOXA2, without increasing expression of other NOX family members. Activation of canonical IL-1 signaling in PDAC cell lines was supported by the observation of IL-1-related upregulation of IL-8 (CXCL8) mRNA, a chemokine essential for neutrophil recruitment and a potent promoter of angiogenesis, in IL-1-treated PDAC cells. Co-administration of Anakinra, an IL-1 receptor antagonist, markedly suppresses IL-1-induced DUOX2/DUOXA2 and CXCL8 expression in vitro . Knocking out DUOX2 in BxPC-3 cells established DUOX2 as the predominant source of IL-1-mediated ROS production. Targeted siRNA knockdown of proximal IL-1 pathway nodes, such as IL-1R1, MYD88 and IRAK1/2, significantly decreased expression of DUOX2/DUOXA2 and of CXCL8. We also found that STAT1 and STAT3, two transcription factors involved in downstream transcription in the IL-1 pathway, are crucial for the regulation of DUOX2/DUOXA2 in pancreatic cancer. Collectively, these findings define an IL-1-STAT1/STAT3 axis that drives DUOX2-dependent ROS production in PDAC, reinforcing a pro-oxidant, pro-inflammatory microenvironment.