Fig. 3: Ablation of USP5 leads to stabilization of p53 resulting in senescence and suppression of tumor growth in vivo.

a A549 or H292 cells stably expressing shUSP5 or control shRNA (shC) were treated with 50 μg/mL CHX for the indicated time intervals before collection. The protein half-life plots were shown. b–d A549 or H292 cells stably expressing shUSP5 were infected with lentiviral-shp53 (#1 or #2) or control shRNA (shC) followed by western blot analyses (b), SA-β-gal staining (c), or colony formation assays (d). Scale bar = 50 μm. e–j A549-Antares2 cells (2 × 10⁶) stably expressing shUSP5 and shUSP5 + shp53 were subcutaneously transplanted into nude mice (n = 5/group). DTZ was injected into tumor regions in anesthetized mice and bioluminescence was subsequently imaged using Caliper IVIS Lumina III (e). Tumors were excised, photos taken (f), and weighted (g). Tumor sizes were measured every other day (h). IHC analyses were performed for Ki67 and SA-β-gal (i, j). Experiments were performed three times independently (a–d). Data were presented as mean ± SD (a, c) or SEM (g, h, j). Comparisons were performed with two-way ANOVA with Bonferroni’s (a) or Tukey’s (c, g, h, j) test. Scale bar = 50 μm.