Figure 1.

Markers of senescence in dox-treated MDA-MB-231 cells. Cells were treated with 100 nM doxorubicin for 24 h, then cultured in a fresh medium and analyzed on subsequent days. (a) Immunocytochemical staining visualized the activity of SA-β-gal (cells stained blue), the accumulation of lipofuscin detected by SenTraGor (cells stained brown) and the accumulation of neutral lipids detected by Oil Red O (red lipid droplets within the cytoplasm). Scale bar: 50 μm. (b) Representative transmission electron microscopy images of cross sections showing increased size and number of vacuoles and lipid droplets. Scale bar: 5 µm. (c) Representative immunofluorescence images of cell morphology. Cells were stained for F-actin (green), nuclei were stained with Hoechst (blue). Scale bar: 50 μm.