Silver nanotriangles and chemotherapy drugs synergistically induce apoptosis in breast cancer cells via production of reactive oxygen species
Chemotherapy is increasingly used in breast cancer treatment; however, drug resistance remains the major limitation and challenge of present chemotherapy. Previous studies indicated that the combination of nanomaterials and chemotherapy drug could overcome such resistance and exhibit a synergistic anticancer effect. The purpose of this study was to evaluate the antibreast cancer effect of cyclophosphamide, gemcitabine, 5-fluorouracil, oxaliplatin, or doxorubicin combined with silver nanotriangles (AgNTs), and screen out the drug with the most broad-spectrum and strongest synergistic activity. Transmission electron microscopy image showed that the synthesized AgNTs were triangular and truncated triangular in shape with a mean edge length of 126 nm. The synergistic antibreast cancer effect of AgNTs plus cyclophosphamide or gemcitabine was found to be cell type-specific, while 5-fluorouracil, oxaliplatin, and doxorubicin displayed synergistic effects with AgNTs on viabilities of various breast cancer cell lines (MDA-MB-231, MCF-7, and 4T1), and doxorubicin was the strongest in general. Furthermore, the synergism was proved to mainly result from reactive oxygen species-mediated cell apoptosis. These findings could potentially be exploited for new highly efficient combination treatment of breast cancer.