MiTMABs induce caspase activation specifically in cells undergoing mitosis. G2/M and G1/S synchronized cells were treated for 8 h with 10 µM MiTMAB, 10 µM OcTMAB or indicated controls (untreated, 0.1% DMSO and 10 µM 2-(DiMA)EM). The lysates (prepared in duplicate) were immunoblotted for cleaved caspase-8, -9, -3 and PARP. These cleaved products were observed in cells treated with MiTMABs that had been synchronized at the G2/M, but not the G1/S boundary. Lysates prepared from cells exposed to UV served as a positive control. β-actin levels were used as a loading control.