Fig. 1

PSMD1 and PSMD2 knockdown inhibits proliferation and induces cell apoptosis. a Cell proliferation was monitored with an MTT assay at the indicated time after treatment with PSMD1 and PSMD2 siRNAs in HepG2 cells. Data are presented as the mean ± SD (n = 3), *p < 0.05. b, c Flow cytometric analysis of the cell cycle distribution at 48 h post-transfection of the negative control (NC) or PSMD1/PSMD2 siRNA in HepG2 cells. The percentages of each phase of the cell cycle (G0/G1, S, and G2/M) are shown. Data are presented as the mean ± SD (n = 3), *p < 0.05, **p < 0.01. d, e HepG2 cells were collected for the detection of apoptotic cells by flow cytometry, 48 h after transfection. In all panels, data are presented as the mean ± SEM of three independent assays. The statistical significance of differences between means was assessed using an unpaired Student’s t-test (*p < 0.05; **p < 0.01) vs. the NC. f Relative mRNA expression of the cell cycle-related genes after transfection of siPSMD1/siPSMD2 and siNC. Independent sample t-tests were used to analyze the statistical differences between groups. *p < 0.05; **p < 0.01. g The mRNA expression levels of several apoptosis-related genes with siPSMD1/siPSMD2 and siNC in HepG2 cells. Independent sample t-tests were used to analyze the statistical differences between groups. *p < 0.05; **p < 0.01. h, i EdU staining after PSMD knockdown. The magnification is ×200. Results are shown as the mean ± SEM of three independent experiments. Independent sample t-tests were used to analysis the statistical differences between groups. *p < 0.05; **p < 0.01