Regarding cancer therapies, a significant problem persists because of the high concentrations of the drug treatments used to prove extremely toxic, besides causing adverse effects. Breast cancer cells that form the tumor in patients can develop resistance to chemotherapy. It is known that nanotechnology provides excellent tools to fight against cancer. One of the most used nanomaterials in biomedicine are silver nanoparticles (AgNPs). Considering the advantages of AgNPs, in this work, we evaluated the cytotoxic and genotoxic effects of different concentrations of AgNPs in combination with tamoxifen on estrogen receptor-positive cells (MCF-7) and estrogen receptor-negative (MDA-MB-231) breast cancer cells. The type of interaction and synergy index analysis using CompuSyn software were evaluated. The genotoxic effect of the combinations was analyzed by cellular imaging using confocal microscopy. The effect of colony-forming capability and proliferation of the breast cancer cell lines exposed to the combinations of AgNPs and tamoxifen were observed by a clonogenic assay for up to 7 days. The production of reactive oxygen species (ROS) induced by AgNPs, tamoxifen, and their combination was evaluated by flow cytometry. The obtained results demonstrate a synergistic cytotoxic effect between the combination of AgNPs and tamoxifen on breast cancer cells. Those combinations were non-genotoxic but induced ROS formation. The clonogenic assay evidenced that the combination resulted in being antiproliferative. This effect was correlated with the cells' morphological changes, the induction of cell death by apoptosis, and an increase in ROS generation. We demonstrated that AgNPs can potentiate the cytotoxic and antiproliferative effect of tamoxifen in breast cancer cell line MCF-7, while the cell line MDA-MB-231 that are no-responsive to this chemotherapeutic showed less genotoxic damage associated with the treatments.

Enhancement of the antiproliferative and cytotoxic effect of AgNPs in combination with chemotherapy drug tamoxifen in ER+ and ER- breast cancer cell lines

ACS Spring Meeting 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.