MASEA: A microfluidic system for in situ evaluation of tumor angiogenesis in PDO-endothelial co-culture.

Patient-derived organoids (PDOs) are promising preclinical models for personalized cancer therapy, but quantitative, time-resolved assessment of PDO-vascular interactions remains difficult. We developed MASEA, an automated microfluidic platform integrating real-time pneumatic fluid control, a PDO culture module, and a custom co-culture/sensing microfluidic chip (MEA-Chip). The system supports perfused PDO-endothelial co-culture in a confined 3D microenvironment and enables in situ measurement of pro-angiogenic factors using a bead-based biosensor, together with standardized image-based quantification of vascular networks. We evaluated MASEA using six lung cancer patient-derived PDO lines co-cultured with HUVECs. Angiogenesis was monitored over 60 h and quantified using total length (TL), number of junctions (NJ), total segment length (TSL), and total mesh area (TMA), while VEGF dynamics were measured in parallel. Across the cohort, co-culture consistently enhanced vascular network formation and increased VEGF levels compared with HUVEC-only controls. Treatment with bevacizumab reduced both angiogenic metrics and VEGF accumulation, demonstrating time-resolved assessment of anti-angiogenic responses. These results establish MASEA as an integrated assay for quantitative analysis of tumor-vascular interactions and for patient-specific screening of anti-angiogenic therapies under controlled microenvironmental conditions.