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bioRxiv · 10.64898/2026.05.04.722641

Epigenetic Control of Spatiotemporal Dynamics of Pancreatic Cancer Cells via Brg1-Rac1 Signaling

Yamamoto, A.·Fukuda, A.·Fukunaga, Y.·Hayashi, K.·Seno, H.·Tanaka, M.
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Abstract

Pancreatic ductal adenocarcinoma (PDA) arises from distinct precursor lesions with different clinical outcomes, yet the mechanisms linking epigenetic regulation to invasive cell behavior remain poorly understood. Here, we investigate how the chromatin remodeler Brg1 influences the dynamic properties of cancer cell migration. Using a biomimetic supported membrane system combined with label-free interferometric imaging, we quantitatively analyze the spatiotemporal dynamics of PDA cells derived from pancreatic intraepithelial neoplasia (PanIN) and intraductal papillary mucinous neoplasms (IPMN). Despite their similar morphology under conventional conditions, PanIN- and IPMN-derived PDA cells exhibit markedly different migration behaviors. PanIN-derived cells migrate faster and display enhanced dynamic remodeling, whereas IPMN-derived cells show persistent elongation with limited displacement. These differences are captured by quantitative analyses of cell trajectories and deformation dynamics. Mechanistically, PanIN-derived PDA cells exhibit elevated Rac1 activity, supporting a model in which a Brg1-Rac1 axis regulates cytoskeletal dynamics and migration behavior. Together, our findings demonstrate that epigenetic regulation is linked to distinct dynamic phenotypes of cancer cells and highlight the importance of quantitative analysis of cell behavior for understanding invasive potential.

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Yamamoto, A., Fukuda, A., Fukunaga, Y., Hayashi, K., Seno, H., Tanaka, M.. 2026-05-07. Epigenetic Control of Spatiotemporal Dynamics of Pancreatic Cancer Cells via Brg1-Rac1 Signaling. https://doi.org/10.64898/2026.05.04.722641

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