The Anti-Breast Cancer Effects of Green-Synthesized Zinc Oxide Nanoparticles Using Carob Extracts

Background: The use of nanoparticles synthesized by the green method to treat cancer is fairly recent. The aim of this study was to evaluate cytotoxicity, apoptotic and anti-angiogenic effects and the expression of involved genes, of Zinc Oxide Nanoparticles (ZnO-NPs) synthesized with Carob extracts on different human breast cancer cell lines. Methods: ZnO-NPs were synthesized using the extracts of Carob and characterized with various analytical techniques. The MCF-7 and MDA-MB231 cells were treated at different times and concentrations of ZnO-NPs. The cytotoxicity, apoptosis, and anti-angiogenic effects were examined using a series of cellular assays. Expression of apoptotic genes (Bax and Bcl2) and anti-angiogenic genes, Vascular Endothelial Growth Factor (VEGF) and its Receptor (VEGF-R) in cancer cells treated with ZnO-NPs were examined with Reverse Transcription quantitative Polymerase Chain Reaction (RT-qPCR). The anti-oxidant activities of ZnO-NPs were evaluated by ABTS and DPPH assay. Results: Exposure of cells to ZnO-NPs resulted in a dose-dependent loss of cell viability. The IC50 values at 24, 48, and 72 hours were 125, 62.5, and 31.2 mu g/ml, respectively (p<0.001). ZnO-NPs treated cells showed, in fluorescent microscopy, that ZnO-NPs are able to upregulate apoptosis and RT-qPCR revealed the upregulation of Bax (p<0.001) and downregulation of Bcl-2 (p<0.05). ZnO-NPs increased VEGF gene expression while decreasing VEGF-R (p<0.001). The anti-oxidant effects of ZnO-NPs were higher than the control group and were dose-dependent (p<0.001). Conclusion: ZnO-NPs synthetized using Carob extract have the ability to eliminate breast cancer cells and inhibit angiogenesis, therefore, they could be used as an anticancer agent.

Automated summary

This study evaluated the cytotoxic, apoptotic, anti-angiogenic effects, and gene expression of Zinc Oxide Nanoparticles (ZnO-NPs) synthesized with Carob extracts on human breast cancer cell lines. The results showed that ZnO-NPs could effectively induce apoptosis, inhibit angiogenesis, and have potential as an anticancer agent.