Abstract 3447: Neutrophil extracellular traps drive the tumorigenic potential in pancreatic ductal adenocarcinoma

Abstract Background: Tumor-infiltrating neutrophils (TINs) have been observed to be linked with poor prognosis in patients with pancreatic ductal adenocarcinoma (PDAC). In the inflammation and oxidative stress-rich tumor microenvironment, neutrophils are likely to undergo neutrophil extracellular traps (NETs) formation which have unique capability of shielding the tumor cells from anti-tumor immune response and facilitate tumor progression. However, the extent of NET infiltration in PDAC and the specific mechanisms by which NETs contribute to tumorigenesis remain unclear. This study aims to investigate NETs infiltration in PDAC and their impact on PDAC progression. Methodology: Tumor-infiltrating neutrophils (CD15) and NETs specific markers (citrullinated histone H3, Myeloperoxidase) in the tumor tissue and blood of 15 PDAC patients and 15 healthy volunteers were determined by flow cytometry, gene expression and immunofluorescence. NETs were cocultured with Panc1 cells to assess their effect on tumor growth and behavior through various tumorigenic assays (MTT, colony formation assay, scratch assay). The gene expression analysis was done for epithelial-mesenchymal transition (EMT), extracellular matrix (ECM) modulation, stemness and dormant cell markers through qRT-PCR and further confirmation at protein level by western blot. Results: In both blood and tissue samples of PDAC patients, relative percentage of NETs were markedly increased and the levels of citrullinated histone is positively correlated with higher tumor stage & grade. Moreover, circulating NETs shows a significant linear positive correlation with local pancreatic tumor NETs, indicates an association between NETs infiltration and disease severity. In vitro, NETs increased tumor migration and induced a more aggressive mesenchymal phenotype. They promoted tumor progression and invasion by downregulating epithelial markers (E-cadherin, ZO-1) and upregulating mesenchymal markers (N-cadherin, Vimentin, Snail, Twist, Zeb1, IL8, TGFβ) as well ECM-modulating markers (αSMA, Desmin, MMP, TIMP). Additionally, NETs contributed to tumor relapse by awakening dormant cancer cells (Dec2, p21, p27, p38) and increasing the expression of proliferative markers (Ki67, ERK, Bcl2) along with stemness markers (Sox2, Oct4, Nanog). Conclusion: NETs contribute to a pro-metastatic cancer phenotype by activating EMT and reactivating dormant cancer cells. Therefore, NETs may serve as independent diagnostic biomarker and a potential therapeutic target in PDAC. Citation Format: Sakshi Bansal, Anjali Aggarwal, Vinit Sharma, Rajesh Gupta, Harjeet Singh, Naresh Sachdeva, Alka Bhatia. Neutrophil extracellular traps drive the tumorigenic potential in pancreatic ductal adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 3447.