Next-GenerationPediatric Cancer Models: Patient-Matched Orthotopic Xenografts, 3D Organoids, 2D Cultures, and Cell Lines for Identification of Therapeutic Vulnerabilities in Pediatric Solid Tumors [scRNAseq]

Most pediatric solid tumor cell lines were established decades ago, so patient-matched organoids and xenografts are not available, limiting their translational utility. Here, we present a new approach to generate triads of patient-matched xenografts, 3-dimensional (3D) organoids, and 2D cultures. We have generated 3D organoids from 135 pediatric tumors, including rhabdomyosarcoma, osteosarcoma, neuroblastoma, Ewing sarcoma, Wilms tumor, and retinoblastoma. We have also generated patient-matched 2D cultures (n=82) and cell lines (n=20). When these 3D organoids, 2D cultures, or cell lines were orthotopically implanted into immunocompromised mice, they replicated the molecular and cellular features of the original patient tumor and xenograft. We have completed 352 single-cell and single-nucleus RNA-sequencing experiments (>2.2 million cells) to confirm that our patient-matched triads preserve tumor cell heterogeneity. All samples are renewable and >3,000 vials have been cryopreserved for unrestricted distribution through the Childhood Solid Tumor Network. We demonstrate the utility of patient-matched triads for identifying therapeutic vulnerabilities, providing a powerful tool for advancing pediatric cancer research.