Fig. 6.

Mechanism of cytotoxicity associated with inhibition of APE-1 in T98G cells exposed to various combinations of AJAY-4 and MeLex for 2, 6, 12, 18, 24, and 26 h and assayed for a caspase-3 and caspase-7 activation; b PARP activation; c PARP cleavage: white diamond, untreated; black diamond, 0.2 % DMSO; green square, 80 μM MeLex + 0.25 μM AJAY-4; blue circle, 0.96 μM AJAY-4 (GI₅₀); open circle, 0.25 μM AJAY-4 (LD₁₀); red solid triangle, 250 μM MeLex (LD₅₀); red open triangle, 80 μM MeLex (LD₁₀); black vertical bar, 20 µM etoposide (used in PARP activation and PARP cleavage experiments