Abstract
Rubus fairholmianus (RF) has widely been used to treat various ailments, including pain,
diabetes, and cancer. Zinc oxide nanoparticles (ZnO NPs) have drawn attention in modern healthcare
applications. Hence, we designed this study to synthesize zinc oxide (ZnO) nanoparticles using R.
fairholmianus root extract to investigate its synergistic cytotoxic effect on MCF-7 cells and explore the
possible cell death mechanism. ZnO NPs were synthesized via green synthesis using R. fairholmianus
root extract, and the effect on MCF-7 cells was determined by looking at cellular morphology, proliferation,
cytotoxicity, apoptosis, and reactive oxygen species (ROS). The results showed that cellular
proliferation was reduced following treatment with R. fairholmianus capped zinc oxide nanoparticles
(RFZnO NPs), while cytotoxicity and ROS were increased. There was also an increase in apoptosis
as indicated by the significant increase in cytoplasmic cytochrome c and caspase 3/7 (markers of
apoptosis), as well as increased levels of pro-apoptotic proteins (p53, Bax) and decreased levels of
anti-apoptotic protein (Bcl-2). In conclusion, these results showed that RFZnO NPs induce apoptosis
in breast cancer cells via a mitochondria-mediated caspase-dependent apoptotic pathway and suggest
the use of acetone root extract of R. fairholmianus for the treatment of cancer-related ailments.