Cancer-selective metabolic vulnerabilities in MYC-amplified medulloblastoma.

MYC-driven medulloblastoma (MB) is an aggressive pediatric brain tumor characterized by therapy resistance and disease recurrence. Here, we integrated data from unbiased genetic screening and metabolomic profiling to identify multiple cancer-selective metabolic vulnerabilities in MYC-driven MB tumor cells, which are amenable to therapeutic targeting. Among these targets, dihydroorotate dehydrogenase (DHODH), an enzyme that catalyzes de novo pyrimidine biosynthesis, emerged as a favorable candidate for therapeutic targeting. Mechanistically, DHODH inhibition acts on target, leading to uridine metabolite scarcity and hyperlipidemia, accompanied by reduced protein O-GlcNAcylation and c-Myc degradation. Pyrimidine starvation evokes a metabolic stress response that leads to cell-cycle arrest and apoptosis. We further show that an orally available small-molecule DHODH inhibitor demonstrates potent mono-therapeutic efficacy against patient-derived MB xenografts in vivo. The reprogramming of pyrimidine metabolism in MYC-driven medulloblastoma represents an unappreciated therapeutic strategy and a potential new class of treatments with stronger cancer selectivity and fewer neurotoxic sequelae.

Preclinical Testing of CAR T Cells in a Patient-Derived Xenograft Model of Glioblastoma.

Glioblastoma (GBM) is the most common malignant adult brain tumor that is resistant to the standard care therapy. Advances in chimeric antigen receptor (CAR) T cell therapies have spurred renewed interest in developing CAR T cell therapies to target chemoradiotherapy-resistant brain tumor-initiating cells. This protocol shows how to isolate peripheral blood mononuclear cells from healthy donors and generate CAR T cells for the antigens of interest, and how to intracranially inject the CAR T cells into a patient-derived xenograft mouse model of GBM. For complete details on the use and execution of this protocol, please refer to Vora et al. (2020).