Short cold atmospheric plasma treatment preserves vascular quiescence in 3D tumor-stroma-endothelial models of pancreatic cancer in vitro and in ovo.

Pancreatic ductal adenocarcinoma (PDAC) features a dense desmoplastic stroma, limiting drug delivery and promoting chemoresistance. While anti-angiogenic strategies have shown limited success, underexplored pro-angiogenic approaches may improve perfusion and treatment efficacy. Cold atmospheric plasma (CAP) generates reactive oxygen and nitrogen species and demonstrates anti-cancer effects at longer treatments and pro-healing, angiogenic effects at shorter treatments. We investigated the impact of short CAP treatment on angiogenesis in PDAC using a triple co-culture spheroid model and a turkey in ovo model, mimicking the tumor microenvironment. CAP was applied via the kINPen MED for 15-60 s in vitro and 10-30 s in ovo. In vitro, CAP inhibited endothelial tube formation treatment time-dependently and reduced VEGF-A secretion, while other angiogenic factors remained unchanged. In ovo, vascularization around the tumor was slightly increased in the BH tumors, while not significantly altered within the tumors, except for a significant reduction after 30 s of CAP treatment. Additionally, a significant increase in tumor weight was observed following short CAP treatment. These findings suggest that under standard conditions, short CAP treatment preserves vascular quiescence in PDAC and may exert subtle tumor-modulating effects, highlighting the importance of treatment parameters and model complexity in CAP-based therapeutic strategies.