Figure 7.

Effect of the c-jun siRNA on the protective role of hypoxia on the paclitaxel-induced apoptosis. MDA-MB-231 cells were incubated under normoxic (N) or hypoxic (H) conditions with or without paclitaxel (tax, 50 μM) or epirubicin (epi, 10 μM) for 16 hours, 8 h post transfection with anti-c-jun siRNA (siRNA) or RISC-free control siRNA (RF) (50 nM, 24 h). After transfection and incubation, the caspase 3 activity was assayed by measuring free AFC released from the cleavage of the caspase 3 specific substrate Ac-DEVD-AFC. Results are expressed in fluorescence intensity, as mean ± 1 SD (n = 3). Statistical analysis were determined independently for the 3 subgroups without siRNA, with anti-c-jun siRNA (siRNA) and with RISC-free control siRNA (RF) ; N.S. = non significantly different from control (N, N siRNA or N RF), ** = significantly different from control (p < 0.01), *** = significantly different from control (p < 0.001); N.S. = no significant difference between N epi and H epi, ### = significant difference between N tax and H tax (p < 0.001), # = significant difference between (1) N epi and H epi or (2) N tax and H tax (p < 0.05). • = significant difference between (1) N tax and N tax RF or (2) H tax and H tax RF (p < 0.05). ••• = significant difference between (1) N tax and N tax siRNA or (2) H tax and H tax siRNA (p < 0.001),