Abstract The adoption of New Approach Methodologies (NAMs) in drug discovery and toxicology is accelerating as the field seeks human-relevant predictive models to replace animal testing. Microphysiological systems (MPS) are leading this transition by enabling physiologically relevant, reproducible in vitro models. Here, we demonstrate construction of vascularized tumoroid models using AIM Biotech’s VasQ Kit and organiX™ platform and Thermo Fisher Scientific patient-derived OncoPro™ Tumoroid Cell Lines. These models combine a microfluidic system optimized for complex three-dimensional (3D) co-cultures with physiologically-relevant tumoroid (cancer organoid) lines. Endothelial cells and fibroblasts, which came pre-validated in the VasQ Kit, were co-cultured with OncoPro tumoroid models in hydrogel matrices to generate perfusable vascular networks. Tumoroids derived from colorectal (HuCo1044-GFP) and lung (HuLu051421) cancers were integrated into organiX devices to assess tumor-vasculature interactions. Fluorescent and confocal imaging with Texas Red-dextran, anti-CD31, and CellEvent™ Caspase-3/7 reagents were used to visualize perfusion, vascular architecture, and apoptosis within tumoroids. Perfusable vascular networks reproducibly formed around patient-derived tumoroids, recapitulating critical features of the tumor microenvironment (TME). Confocal imaging revealed active vasculature-tumoroid interfaces, with endothelial networks penetrating hydrogel matrices and surrounding tumor masses. Quantification of apoptotic markers and spatial analysis of immune or stromal cell compartments demonstrated the model’s capability for assessing drug response and cellular infiltration. This method establishes a standardized and human-relevant MPS model for vascularized tumoroids, enabling mechanistic studies of tumor biology, immune cell trafficking, and therapeutic efficacy. This integrated approach supports the broader transition toward NAMs and offers a translationally relevant platform for immuno-oncology and precision medicine research. Citation Format: Geetika Sahni, Hooi Linn Loo, Colin D. Paul, Matthew R. Dallas, Sei Hien Lim, Kuan Chee Mun. Development of vascularized 3D tumoroid models using microphysiological systems abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 4922.
Sahni et al. (Fri,) studied this question.