FAF1 is associated with a FAS-mediated apoptosis response and restoration of the FAF1 protein in adult glioma cell lines significantly increases cell death [20], whilst in MTAP-deficient cells, methylthioadenosine, generated during polyamine biosynthesis, is not cleaved and the salvage pathway for adenine and methionine is absent [21]. Here, MTAP is linked to central nervous system cancer.