However, the intracellular concentration of AICA was much greater than the Km of HPRT1 for AICA even at low amounts (>50 μM) of TMZ treatment (Supplementary Fig. 3g), compensating the low efficiency of this reaction and suggesting that the HPRT1-mediated AICA conversion is sufficient after treatment of GBM cells with TMZ. Here, HPRT1 is linked to glioblastoma.