Figure 7. Effects of Trichostatin A on GLCE, TCF4 and β-catenin expression and GLCE transcriptional activation in MCF7 breast carcinoma cells in vitro. (A) GLCE, TCF4 and β-catenin expression upon treatment with 5-aza-deoxycytidine (5-aza-dC) and/or Trichostatin A (TSA). Representative multiplex RT-PCR electropherogram with GAPDH gene as an internal control. (B) Intensity of the amplified DNA fragments normalized to that of GAPDH. Bars represent the mean ± SD of triplicate experiments (OriginPro 8.1). (C) ChIP assay for the GLCE promoter region with anti-TCF4 or anti-β-catenin antibodies. DNA fragments corresponding to TCF4-responsive region of the GLCE promoter were amplified using P1 primers, TCF4-non-responsive promoter regions were amplified with P2 and P3 primers as control. The amount of immunoprecipitated DNA was normalized to that of the input DNA, TSA concentration was 400 ng/ml.