Higuchi et al., using isogenic pairs of glioma cells with or without RNAi-mediated MSH6 deficiency, found that PARP inhibition alone did not significantly influence cell viability, independently of IDH and MSH6 status, whereas it was sufficient to restore TMZ chemosensitivity in MSH6-inactivated glioma [57]. Here, IDH2 is linked to central nervous system cancer.