Apoptotic potential of TAM and/or tranilast monitored by TUNEL staining in MCF-7 (A) and MDA-MB-231 (B) cells. Phase micrographs of a negative control group; b positive control group; c 2 μM TAM; d 200 μM tranilast; e 2 μM TAM + 200 μM tranilast. f Columns mean percentage of apoptotic cells from three independent experiments performed in triplicate. White arrows indicate yellow-stained nuclei (TUNEL-positive cells). p values were determined using one-way-ANOVA (*p < 0.05 compared with control; **p < 0.01 compared with control). Scale bar: 10 μm.