Fig. 6: USP26 promotes HCC tumorigenesis by stabilizing SIRT1.

Western blot analysis (a), MTT (b) and colony formation (c) assays of USP26-knockdown MHCC97H cells with or without shRNA-resistant USP26 or SIRT1 overexpression. Western blot analysis (d), MTT (e) and colony formation (f) assays of USP26-knockdown HCCLM3 cells with or without USP26 (shRNA-resistant USP26) or SIRT1 overexpression. g. An EdU staining assay was carried out on USP26-knockdown and SIRT1 restored Huh7 and HCCLM3 cells. Flow cytometry was carried out to screen the active DNA replicated cells. h The apoptosis rates of USP26-knockdown and SIRT1 restored MHCC97H cells were measured by flow cytometry after Annexin/V/PI dual staining. i Immunoblotting of cleaved PARP in USP26-knockdown SIRT1restored MHCC97H cells. j Immunoblotting of the indicated proteins in USP26-knockdown MHCC97H cells with or without shRNA-resistant USP26 or SIRT1 overexpression. k The relative p66Shc mRNA levels in USP26-knockdown MHCC97H cells with or without shRNA-resistant USP26 or SIRT1 were detected by RT‒qPCR. l Representative images of xenograft tumors derived from USP26-knockout (KO) HCCLM3 cells with or without USP26 or SIRT1 overexpression. Scale bar: 10 mm. m The volumes of tumors burdened in nude mice receiving the HCCLM3 cells were measured on different days after implantation. n Weights of the mouse xenograft tumors. Each graph is presented as the mean ± SEM. Each blot data is representative of three independent experiments. b, e n = 4 independent experiments; c, f, g, h, k n = 3 independent experiments; (m, n) n = 4 mice per group. Statistical significance was calculated by (b, e, m) two-way ANOVA; (c, f, g, h, k) one-way ANOVA; (n) two-tailed unpaired t-test. Source data are provided as a Source Data file.