Effect of cisplatin and SAHA on induction of apoptotic cell death in VAT-39 cells. ( A ) Immunohistochemical localization of cleaved caspase-3 in 5 μM cisplatin and 2 μM SAHA-treated VAT-39 cells. ( B ) Counts of cleaved caspase-3-positive cells are shown in the bar graph. ( C ) Western blot analysis detected double bands of cleaved caspase-3 (17 kDa and 19 kDa). Isolated proteins (20 μg) were subjected to SDS-PAGE. β-actin (42 kDa) was used as a loading control. ( D ) Cell death was examined by TUNEL assay using the Mebstain apoptosis TUNEL kit. Arrows indicate TUNEL-positive cells among cisplatin and SAHA-treated cells. *** P