Figure 6

Inhibition of HSP90α by 17-AAG defines roles for survival as well as apoptosis in HC11 cells. The presence of mono- and oligo-nucleosomes was measured as an indication of apoptosis (apoptotic index). (a) HC11-heat shock protein 90 alpha (HSP90α) cells or (b) HC11-EV cells were differentiated and left untreated or treated with 1 μM of 17-allylamino-17-demethoxygeldanamycin (17-AAG) in either differentiation medium (prolactin, dexamethasone and insulin (DIP)) or starvation medium for 24 hours. Comparison of untreated to 17-AAG-treated HC11-HSP90α (t-test *p = 0.003) or HC11-EV (t-test *p = 0.006) cells after differentiation. Comparison of untreated to 17-AAG-treated HC11-HSP90α (t-test *p = 0.04) or HC11-EV (t-test *p = 0.001) cells in the absence of serum and hormones. Each bar represents the average of three experiments with standard deviation. Each cell line was tested independently and so the absolute levels of nucleosomes can be compared only within each panel.