Search Results (2)

Background: Most preclinical studies on glioblastoma (GBM) fail to provide translational utility in the clinic. Fluorescence-guided surgery using 5-aminolevulinic acid (5-ALA) improves tumor resection, disease prognosis, and, thus, patient outcomes. Given the critical role of surgery in managing recurrent GBM, it is essential to incorporate surgical elements into preclinical models to accurately reflect clinical scenarios and enhance translational success. However, existing protocols for 5-ALA-guided resection in preclinical models are limited and often lack clinical relevance. Methods: To address this gap, we developed a novel protocol for the 5-ALA-guided resection in two mouse GBM models: TRP-mCherry-FLuc and GL261 Red-FLuc. Results: The resection of TRP-mCherry-FLuc tumors significantly extended survival and mitigated weight loss compared to controls. Similarly, GL261 Red-FLuc tumor resection increased survival, reduced body weight loss, and slowed tumor progression. Conclusions: This study presents a clinically relevant protocol for 5-ALA-guided resection in preclinical GBM models, providing a platform for future research to integrate adjuvant therapies and enhance their potential translation into clinical practice. Full article

Glioblastoma (GBM) is the most aggressive brain cancer. To model GBM in research, orthotopic brain tumor models, including syngeneic models like GL261 and genetically engineered mouse models like TRP, are used. In longitudinal studies, tumor growth and the treatment response are typically tracked with in vivo imaging, including bioluminescence imaging (BLI), which is quick, cost-effective, and easily quantifiable. However, BLI requires luciferase-tagged cells, and recent studies indicate that the luciferase gene can elicit an immune response, leading to tumor rejection and experimental variation. We sought to optimize the engraftment of two luciferase-expressing GBM models, GL261 Red-FLuc and TRP-mCherry-FLuc, showing differences in tumor take, with GL261 Red-FLuc cells requiring immunocompromised mice for 100% engraftment. Immunohistochemistry and MRI revealed distinct tumor characteristics: GL261 Red-FLuc tumors were well-demarcated with densely packed cells, high mitotic activity, and vascularization. In contrast, TRP-mCherry-FLuc tumors were large, invasive, and necrotic, with perivascular invasion. Quantifying the tumor volume using the HALO^® AI analysis platform yielded results comparable to manual measurements, providing a standardized and efficient approach for the reliable, high-throughput analysis of luciferase-expressing tumors. Our study highlights the importance of considering tumor engraftment when using luciferase-expressing GBM models, providing insights for preclinical research design. Full article