Abstract B022: Spatial multi-omics of mitochondrial lipid remodeling and metabolism identified therapeutic vulnerabilities in glioblastoma

Abstract Glioblastoma (GB) is the most common and lethal primary brain tumor in adults, marked by high spatiotemporal heterogeneity and plasticity. Multisampling during surgical resection has enabled the investigation of intra- and intertumoral heterogeneity through preserving the organization of the TME. Metabolic reprogramming is an adaptive mechanism that supports proliferation, invasiveness, and therapeutic resistance. We have previously demonstrated that cardiolipin fatty acyl chain composition regulates mitochondrial structure and function to reduce growth and proliferation in the pediatric brain tumor, embryonal tumor with multilayered rosettes. Building on our previous findings, we integrated spatial lipidomics and proteomics to study metabolic reprogramming associated with cell phenotypes within and across GB patient samples and matched primary 3D cell models. Our objective was to identify dysregulated mitochondrial lipid signaling and metabolic pathways that can be targeted therapeutically. Our hypothesis is that multisampling of GB tumors combined with integrated spatial multi-omics will identify TME niches that contribute to mitochondrial plasticity. Primary and recurrent longitudinal samples were surgically resected from GB patients. In addition to frozen specimens, fresh samples were processed to generate region-specific patient-matched primary 3D models. Spatial lipidomics and proteomics were carried out on the same or adjacent sections using mass spectrometry imaging and multiplex immunofluorescence. Data analysis was carried out using the SciLs lab, QuPath, Leica LAS X and the Imaris software suites. Individually processed data were integrated for multimodal spatial analysis. We detected a structure-specific accumulation of the mitochondrial specific lipid, cardiolipin in different glioblastoma tumor niches within and across patient samples. Regions of nestin positive proliferative tumor cells with an abundance of vascular proliferations were characterized by a high accumulation of shorter acyl chain cardiolipins within fragmented mitochondria. Whereas peritumoral regions characterized by reactive astrocytes and lower vascular proliferations contained longer acyl chain CLs and elongated mitochondrial networks. Analysis of the region-specific patient-matched 3D models identified similarities and differences in mitochondrial phenotypes that were based on proliferation and migratory status. These data indicate differences in metabolic functions in migratory vs. actively proliferating tumor cells in the peritumor vs. tumor regions, respectively. Ongoing studies are focused on identifying the cardiolipin acyl chain remodeling enzymes that can be targeted therapeutically to modulate mitochondrial phenotypes and tumor growth. Citation Format: Adele Asia Ponzoni, Evangelos Liapis, Lea Anne T. Maristela, Elizabeth E. Ginalis, Linda Szymanski, Kar Fai Chow, Kangmin Lee, George J. Kaptain, Claire L. Carter. Spatial multi-omics of mitochondrial lipid remodeling and metabolism identified therapeutic vulnerabilities in glioblastoma abstract. In: Proceedings of the AACR Special Conference in Cancer Research: Brain Cancer; 2026 Mar 23-25; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2026;86 (6Suppl): Abstract nr B022.