TMOD-38. Spatially Paired Glioblastoma Organoid and Xenograft Model derived from tumor core and invasive front Reveal Distinct Metabolism, Regional Tumor Behaviors and Therapy Responses

Abstract Intratumoral heterogeneity in glioblastoma (GBM) remains a major barrier to effective therapy. Spatial variations in tumor biology contribute to treatment resistance and recurrence but remain underexplored in preclinical models. To address this, we developed spatially paired GBM models derived from anatomically distinct tumor regions—the invasive cortical margin and the solid tumor core—using both patient-derived tumor tissue (Pt-NBRX121GBM-Cortex and Pt-NBRX121GBM-Solid) and matched xenograft tumors (IC-NBRX121GBM-Cortex and IC-NBRX121GBM-Solid). From each region, we established three-dimensional organoid cultures and patient-derived orthotopic xenografts (PDOX), preserving regional biological characteristics. We conducted longitudinal survival studies in SCID mice, confocal imaging to assess organoid structure and metabolism, single-cell RNA sequencing (scRNA-seq), and high-throughput drug screening. PDOX models from cortex and solid regions showed moderate differences in median survival (76.0 to 88.5 days), but no statistically significant differences under comparable tumor burden, suggesting similar in vivo aggressiveness. In contrast, organoid analyses revealed pronounced region- and source-specific distinctions. Cortex-derived organoids, especially larger ones, exhibited disorganized morphology, peripheral mitochondrial clustering, and metabolic stress, while solid-derived organoids maintained spherical structure, strong mitochondrial-nuclear association, and high proliferative capacity. In vivo, cortex-derived tumors displayed diffuse infiltration, elevated mitochondrial activity, and mesenchymal-like gene expression, whereas solid-core tumors showed compact growth, increased proliferation, and hypoxia-driven angiogenesis. scRNA-seq confirmed distinct transcriptional programs consistent with these phenotypes. High-throughput drug screening uncovered region-specific therapeutic vulnerabilities, with cortex-derived models showing sensitivity to anti-migratory compounds and solid-derived tumors responding to agents targeting angiogenesis and metabolism. This spatially defined GBM organoid and PDOX platform captures key features of tumor heterogeneity across structure, metabolism, gene expression, and therapy response. These models provide a robust and scalable system for dissecting region-specific tumor biology and for advancing precision therapeutic strategies in glioblastoma.