CASP3 and cancer: To illustrate whether rutin-induced cytotoxicity in HeLa cancer cells was associated with the activation of three caspases (caspase-3, -8 and -9), HeLa cells were pretreated with 50 μM of caspase-3, -8 and -9 inhibitors (Z-DEVD-FMK, Z-IETD-FMK and Z-LEHD-FMK) for 2 h and then treated with selective doses of rutin for 24 h.