TNFSF10 and glioblastoma: Similarly to the established GBM cells, the combination of Olaparib and TRAIL led to a significant increase in apoptosis induction as compared to the single agent treatments (Fig. 1H and Figure B in S4 Fig.), suggesting that the combined treatment of Olaparib with recombinant human TRAIL not only affects the bulk of the tumor cells but more importantly targets the stem cell population of GBM cells, which according to the recent literature may be responsible for the rapid recurrence of these tumors.