Another member of the BCL-2 family, Mcl-1, is downregulated in IDH1mt glioma cells, inducing a dependence on the anti-apoptosis protein Bcl-xL and thus the synthetic lethality of IDH1mt with Bcl-xL inhibitor (Karpel-Massler et al., 2017). This evidence concerns the gene BCL2L1 and central nervous system cancer.