Western immunoblot analysis of ATO-induced PARP, caspase-3, -8, and -9 activation in wt and mutated p53-expressing myeloma cells.

ARP-1, IM9, U266, and HS-Sultan cells were cultured for 0, 16, 24, and 48 hours with or without 7.5 μM ATO. Extraction of cellular protein, SDS-PAGE, immunoblotting, and detection of specific protein bands were performed as described in “Materials and methods.” Representative results from at least 3 different experiments are shown. For loading controls, membranes were striped and reprobed for β-actin. For additional experimental details, see “Materials and methods.”