NF1 and pleomorphic xanthoastrocytoma: pLGG in vitro cell line models derived from human primary tumors range from PA with a BRAF-fusion or -V600E mutation only (DKFZ-BT66, -BT308, -BT314, and -BT317) [43, 44] or NF1 loss (JHH-NF1-PA1) [105], to pleomorphic xanthoastrocytoma (PXA) with BRAFV600E mutation and CDKN2A/B deletion (BT40) [46].