Fig. 1

25-hydroxycholesterol induced ERβ expression. (A) BALB/c nude mice were intravenously inoculated A549 cells, and feed with normal diet or high cholesterol diet for 8 weeks. The serum levels of 25-hydroxycholesterol (25-HC) in non-bone metastatic and bone metastatic mice were determined using LC-MS method. (B) A549 and SPC-A1 cells were exposed to 0, 0.013 and 0.085 µM 25-HC for 48 h. The mRNA expression of ERβ was measured by qPCR analysis. (C) A549 and SPC-A1 cells were exposed to 0, 0.013 and 0.085 µM 25-HC for 48 h. The protein expression of ERβ was measured by western blot analysis. (D) A549 and SPC-A1 cells were transfected with the lentivirus carrying ESR2-sgRNA, and the protein expression of ERβ was measured by western blot analysis. (E) After ERβ knockdown, A549 and SPC-A1 cells were exposed to indicated concentration of 25-HC for 48 h. The protein expression of ERβ was measured by western blot analysis. Data were shown as mean ± SD of at least three independent experiments. *, p < 0.05; **, p < 0.01; ***, p < 0.0001