Hoechst 33342 staining

MCF-7 and MDA-MB-231 cells at a density of 2×10⁴ cells/well were seeded in 24-well plates, and after incubation for 24 h, fresh culture media or fresh culture media containing Alo (0, 0.1, 0.2 and 0.4 mM) were added, and incubated in a humidified incubator at 37°C for 24 h. Then the cells were stained with Hoechst 33342 (10 mg/ml) in culture medium at room temperature in the dark for 20 min. Subsequently, the cells were washed twice with PBS and immediately evaluated by a microscope.