Further characterisation by matched single cell RNA-sequencing of the same tumours revealed that BCL-xL and MCL-1 expression correlated with expression of neural stem cell markers NES, SOX2 and SOX9 and the degree of malignancy within the tumours (CNA gain chromosome 7) (Fig. 1F), independently of cell cycle (Supplementary Fig. 1A). Here, SOX9 is linked to neoplasm.