PARP1 and glioblastoma: GBM cells exhibit increased resistance to staurosporine (STS)-induced apoptosis, supported by fewer TUNEL-positive cells (Figure 4 – Figure Supplement 2A, B) and markedly diminished PARP-1 (Poly ADP-ribose polymerase) cleavage (Figure 4 – Figure Supplement 2C), a marker of AIF-mediated apoptosis (55).