Fig. 4

Quercetin causes apoptosis of cancerous RB Y79 cells via intrinsic pathways. a and b The Y79 cells were exposed to Quercetin (0-100 μM). The obtained cell lysates after 24 h were analyzed by western blot using specific antibodies against caspase-9, caspase-3 and cytochrome c, GAPDH was used as a loading control. *P < 0.05, **P < 0.01 against control (n = 3). @P < 0.05, @@P < 0.01 against Quercetin 50 μM. c Y79 cells were exposed to 100 μM Quercetin for 24 h in the presence or absence of ZVAD-FMK. Viability of cells was done by the Cell Counting Kit-8, the data are presented as the percentage of control cells, means ± SD (n = 3), **P < 0.01 against control, @P < 0.05 against Quercetin treated group. d Quercetin exposed apoptosis was blocked by ZVAD-FMK treatment, the data presented are means ± SD (n = 3). **P < 0.01 against control, @P < 0.05 against Quercetin treated group