Fig. 5.

TRAP IL-1 blocks CTX-induced β-galactosidase activity in SW48 while increasing it in SW48 CXR. SW48 and SW48 CXR cells were seeded in 12-well plates in 10% of FBS medium and treated the following day with CTX (50 μg/ml), IL-1 (α + β 10 ng/ml each), and TRAP (20 μg/ml). After 4 days, cells were washed, fixed, and stained with β-galactosidase for 5 h at 37 °C. Photos were taken at 20× magnification (Leica). Scale bar, 50 μm (a). The histograms show analysis of positively stained cells (mean ± SEM) for SW48 and SW48 CXR, respectively (b). Statistical analysis was carried out using one-way ANOVA with Tukey’s multiple comparison test. (c) The model depicted in the cartoon describes how, in the CTX-sensitive phase, IL-1 induces pseudo-senescence and growth-arrest, but in resistant cells, IL-1 pushes cells into a post-senescence stage