Figure 5.

Hes1 represses the activity of the PTBP3 promoter but did not affect PTBP3 protein expression. (A) MKN45 cells were cultured and lysates were subjected to ChIP assay. Four paired primers were designed near the predicted binding sites of Hes1. The ChIP assays verified the association of Hes1 and the promoter of PTBP3 gene. The results are expressed as the mean ± S.D. of three independent experiments. **P < 0.01, ***P < 0.001 vs. anti-IgG. (B) The 5′-upstream promoter region (1,098 bp) was inserted into the pGL3-basic plasmid. Reporter activity was also analyzed after transfection of pcDNA (Hes1) into gastric cancer cells. All error bars are mean ± S.D., n = 3. *P < 0.05. (C) Cells in Si-NC group were transfected with non-targeting siRNA as a negative control. In Si-Hes1 group, cells were treated with Hes1 siRNA. The pcDNA-NC group refers to cells transfected with a blank vector. The pcDNA-Hes1 group refers to cells transfected with Hes1-overexpressing plasmids. After 48 h following transfection, total proteins were extracted, and Hes1 and PTBP3 protein expression were measured. Hes1 expression has no influence on PTBP3 expression in MKN45 and HGC27 cells.