Fig. 5

USP21 stabilizes BRCA2 in HCC cells to promote tumor cell growth. a Western blot analysis of the indicated proteins in the HuH1 hepatoma cell line in the presence or absence of USP21 knockdown. b Western blot analysis and clonogenic survial of HuH1 cells in the presence or absence of BRCA2 knockdown. Colony formation was scored in triplicate and normalized to sh-Luc. Values are expressed as mean and s.d. c Clonogenic survival of HuH1 cells in the presence or absence of USP21 knockdown. Colony formation was scored in triplicate and normalized to sh-Luc. Values are expressed as mean and s.e.m. from three independent experiments. d HuH1 oncosphere formation in the presence or absence of USP21 knockdown. Sphere formation was scored in triplicate and normalized to sh-Luc. Values are expressed as mean and s.d. Representative images are shown, scale bar: 100 µm. e, f Clonogenic survival e and Western blot analysis f after USP21 depletion in HuH1 cells stably transfected with either empty vector or Flag-BRCA2 (BRCA2-OE). The efficiency of colony formation in sh-USP21 cells was normalized to sh-Luc controls. Samples were analyzed in triplicate, values are expressed as mean and s.d. g Clonogenic survival of CAPAN-1 cells in the presence or absence of USP21 knockdown. Samples are normalized to sh-Luc. Values are expressed as mean and s.e.m. from five independent experiments. A schematic of the CAPAN-1-specific BRCA2 truncation is shown. h HuH1 cell xenograft assay in the absence or presence of USP21. A total of 10 sites were injected per genotype and tumor size was monitored for the indicated time frame. Image and weights are from tumors isolated 6 weeks after injection, scale bar: 1 cm. Values are expressed as mean and s.e.m. p-values are based on Student’s two-tailed t-test: *p < 0.05, **p < 0.01, ***p < 0.001