CASP3 and glioblastoma: Then, to better describe the mechanism driving the cell death induced by these aporphine and isoquinoline derivatives on GBM cells, we evaluated the presence of cleaved caspase-3 in U3017MG cells after 48 h-treatment with 150 μM TMZ, 25 μM APO, 30 μM A5 or 30 μM C1, which corresponds approximately to the IC50 value for each compound.