Figure 3.
[5,5′-3H2]AHPN binding to Sin3A- and 3-Cl-AHPC–mediated apoptosis is dependent on HSP90 ATPase activity and Sin3A expression. MDA-MB-468 cells were incubated with either vehicle or 1 μg/mL geldanamycin (Geld) for 2 h and then exposed to AHPN and 3-Cl-AHPC or vehicle for 24 h. 3-Cl-AHPC induction of Sin3A-associated HDAC activity (A), [5,5′-3H2]AHPN Sin3A binding (B), and 3-Cl-AHPC–mediated apoptosis (C) in cells treated with and without geldanamycin. D, effect of Sin3A loss of expression in MDA-MB-468 cells on 3-Cl-AHPC–mediated apoptosis. Cells were exposed to vehicle or 1 μmol/L 3-Cl-AHPC for varying times.