Figure 2

Relative content of reactive oxygen species in unirradiated and irradiated MCF-7 monolayer and mammosphere cells. Cells were incubated with aminophenyl fluorescein, exposed to 0, 1, 4 or 10 Gy ⁶⁰Co γ-radiation, and immediately afterwards the relative fluorescence of each sample was measured by excitation at 485 nm and emission at 515 nm. Error bars represent the mean ± standard error of the mean from three independent experiments.