Given that the SXO210 model was derived from a GBM with an NF1 loss-of-function mutation61 (Figure 2Z), we hypothesized that SXO210 organoids may be enriched for mesenchymal-type glioma cells that actively degrade pyrimidine nucleotides produced by the glutamine-dependent de novo synthesis pathway. Here, NF1 is linked to glioblastoma.