In our study, the concentration of total and reduced glutathione after 24 h and 72 h of incubation with various concentrations of FUAgNPs and SVAgNPs showed only a weak increase in the levels of glutathione compared to the control, suggesting that almost non-altered Nrf-2 levels could be in correlation with low de novo synthesis of glutathione in breast cancer cells in response to oxidative impact. The gene discussed is NFE2L2; the disease is breast cancer.