Fig. 3: siRNA-mediated LSD1 and JMJD3 knockdown synergistically inhibits cell proliferation and induces cell apoptosis in vitro.

a The protein levels of LSD1, JMJD3 and H3K4me2, H3K27me3 following TCP and JMJD3 treatment, were determined by western blot. Total H3 and β-actin were used as loading controls, respectively. b, c Cell proliferation was measured by CCK-8 viability assay in Cal27 and FaDu cells transfected with siRNAs as indicated for 48 h. d The potentials and quantifications of colony formation were significantly inhibited in Cal27 and FaDu cells transfected with siRNAs as indicated. e Increased percentages of apoptotic cells were evident in cells transfected with both LSD1 and JMJD3 targeting siRNAs. Cell apoptosis was assayed via Annexin V–PI staining. f, g JMJD3 knockdown sensitised cells to TCP treatment in vitro. Cell proliferation was measured when cells were initially transfected with siJMJD3 and then treated with TCP (0.8 mM in Cal27 and 0.75 mM in FaDu) by CCK-8 assay. h, i LSD1 knockdown sensitised cells to GSK-J1 treatment in vitro. Cell proliferation was measured when cells were initially transfected with siJMJD3 and then treated with GSK-J1 (20 μM in Cal27 and 15 μM in FaDu) by CCK-8 assay. Data shown here are mean ± SD from three independent experiments, *P < 0.05, ANOVA analyses with Tukey's multiple comparisons test.