Apoptosis, Microtubule

PBOX 6 is a potent apoptotic PBOX, but does not elicit a general toxic effect in a rat R2C Leydig cell line. PBOX 6 (0-25 μM, 16 h) results in dose- and time-dependent induction of apoptosis, and also causes DNA fragmentation at 10 μM in HL-60 cells. PBOX 6 (10 μM) induces apoptosis through activation of caspase 3-like proteases in HL-60 cells. PBOX 6 (10 μM) induces apoptosis and exerts an accumulation of cytochromec in the cytosol, but this effect is not triggered by oxidative stress, and is independent of peripheral-type benzodiazepine receptor (PBR) and NF-κB. PBOX 6 (25 μM) induces apoptosis in MCF-7 cells through activation of caspase-7. PBOX 6 (10 μM) induces the redistribution of cypA from the nucleus to the cytosol of the cell in K562 cells. PBOX 6 (10 μM) induces nucleocytoplasmic redistribution of cypA and pin1 through a JNK-dependent manner, also dependent on upstream activation of a trypsin-like serine protease, and this effect correlates with G2/M arrest in K562 cells.