CASP9 and breast carcinoma: Consistent with our findings, a previous study [67] also observed an increase in caspase activity (caspase 3 and 9) in MCF-7 breast cancer cells treated with the compound, particularly in caspase 3 and caspase 9 when exposed to silver nanoparticles derived from Achillea biebersteinii, a plant within the Asteraceae family at a concentration of 25 μg/mL.