Pancreatic Cancer Cell-derived Migrasomes Promote Cancer Progression by Fostering an Immunosuppressive Tumor Microenvironment

Pancreatic cancer is distinguished by an immunosuppressive tumor microenvironment (TME) that facilitates cancer progression. The assembly of the TME involves numerous contributing factors. Migrasomes, recently identified as cellular organelles in migrating cells, play a pivotal role in intercellular signaling. However, research into their involvement in cancers remains nascent. Thus far, whether pancreatic cancer cells generate migrasomes and their potential role in TME formation remains unexplored. In this study, it was found that both murine and human pancreatic cancer cells could indeed generate migrasomes, termed pancreatic cancer cell-derived migrasomes (PCDMs), which actively promote cancer progression. Moreover, utilizing chemokine antibody arrays and quantitative mass spectrometry analysis, we observed significant differences between the chemokines, cytokines, and proteins present in PCDMs compared to their originating cell bodies. Notably, PCDMs exhibited an enrichment of immunosuppression-inducing factors. Furthermore, macrophages could directly uptake PCDMs, leading to the expression of high levels of M2-like markers and secretion of tumor-promoting factors. PCDM-induced macrophages played a pivotal role in inhibiting T cell proliferation and activation partially through ARG-1. In summary, this study provides compelling evidence that pancreatic cancer cells generate migrasomes, which play a crucial role in promoting tumor progression by contributing to an immunosuppressive TME. The exploration of migrasomes as a therapeutic target could pave the way for the development of tailored immunotherapies for pancreatic cancer.