Fig. 4

ZHX2 binds to the S100A14 promoter to repress its expression. A RT–qPCR analysis of ZHX2 and S100A14 mRNA levels in thyroid cancer cells with ZHX2 overexpression or knockdown. B Diagram of the S100A14 promoter region and S100A14 promoter luciferase constructs are presented in the top panel. The promoter activity of pGL3-S100A14 was verified by the dual luciferase assay (lower panel). C S100A14 promoter activity was measured in 8305C cells with or without ZHX2 overexpression using a dual fluorescent reporter assay. D The ChIP assay was used to analyse ZHX2 occupancy on the promoter of S100A14. 8305C cells were transfected with a plasmid encoding ZHX2. HA antibody was used to pull down DNA–protein complexes in these cells. Primers targeting S100A14 promoter regions (S1–S4) are shown in the top panel. The lower panel presents the quantification of qPCR (left) and semiquantitative images (right). Data are presented as the mean ± SD. Student’s t test. *p  < 0.05, **p  < 0.01, ***p  < 0.001