MODL-28. Patient-derived, three-dimensional organoid platform for pediatric brain tumor modeling

Brain tumors have become the leading cause of cancer-related death in children. An important hurdle to scientific and clinical progress in the field has been the limited availability of preclinical tumor models. Historically, few pediatric brain tumor cell lines have been established and these often poorly recapitulate the phenotypes of the original tumors. In recent years, the Children’s Brain Tumor Network (CBTN) has accelerated the development of patient-derived cell lines and xenografts, offering these resources to the community through open-source access. While these models are extremely valuable, their development process can be lengthy and result in clonally selected lines which presents a challenge for studying complex tumor biology. To address the need for three-dimensional tissue culture, our group in conjunction with CBTN, utilized organoid culture from fresh tissue specimens obtained directly from surgical resection of various pediatric brain tumor histologies. This resulted in the development and banking of over 30 organoid models, which included ependymoma, high-grade glioma, medulloblastoma, atypical teratoid-rhabdoid tumor, diffuse midline glioma, and low-grade glioma diagnoses. Tissue was processed within an hour post extraction and cultured with universal media composition for each diagnosis. Organoid growth was observed within 2-3 weeks of initiation and continued for up to three months before banking. Banked organoids established growth upon return to culture. Phenotypic analysis revealed organoid cell composition that represented clinical histology. Importantly, organoids returned to culture post-banking demonstrated similar cell composition to those in the original culture, indicating their utility for subsequent preclinical testing. Here we provide a simple and efficient workflow for the generation and characterization of three-dimensional tumor organoids generated from fresh surgical pediatric brain tumor tissue. The platform has the potential to accelerate investigations into tumor biology and empower a diverse array of translational studies for the pediatric brain tumor field.