Fig. 1.

G9a inhibition represses breast cancer cell growth and proliferation in vitro and in vivo. Proliferation assay. a Silencing G9a repressed breast cancer cell colony formation ability (up panel) and cell growth (down panel). Western blotting analysis of G9a depletion in breast cancer cells. b Overexpressed G9a in MCF-7 and MDA-MB-231 cells promoted colony formation (up panel) and cell growth (down panel) in vitro. n = 3. c G9a loss arrested breast cancer cells in the G1 phase. The cell cycle of G9a knockdown cells or breast cancer cells treated with 5 µM G9a inhibitor UNC0638 for 24 h was investigated by flow cytometry. d G9a inhibitors arrested breast cancer cells in G1 phase. Protein levels of c-Myc, Cyclin D1, E2F1 and p21 in G9a inhibitor-treated MCF-7 and MDA-MB-231 cells were tested. e Breast cancer cells treated with G9a inhibitors UNC0638 and BIX-01294, and the inhibitory effects on cell proliferation were measured using the Sulforhodamine B (SRB) assay (mean IC₅₀ values were calculated from at least three independent experiments). f The inhibition of breast tumor growth in vivo of S1 G9a knockdown cells was assessed. n = 6. Each bar represents the mean ± SD. Results were representative of three independent experiments, *P < 0.05, **P < 0.01 and ***P < 0.001