Entosis quantification

Cells were seeded, stained, and treated on sterile 12-mm glass-bottom WillCo-dishes in RPMI medium at 37°C with 5% CO₂. Entosis events were determined by counting at least 500 cells/sample by either using time-lapse microscopy images or 3D confocal microscopy of immunofluorescence staining (Hoechst and β-catenin) after 48 h of treatment. Events were quantified based on detecting round-shaped (Hoechst-stained) cells inside a large vacuole within another (Hoechst-stained) cell showing a crescent-shaped nuclear morphology. Both dead and alive inner cells were quantified as entotic.