Figure 4.

The FOXP3/HAT1 axis epigenetically alters CCR4 promoter to promote Treg infiltration in tumor site. (A) The relative binding of FOXP3 to its putative responsive elements on the CCR4 promoter has been graphically depicted in FOXP3-ablated/-overexpressed Treg cells. (B) The binding of both FOXP3 and HAT1 to the CCR4 promoter in FOXP3-ablated/-overexpressed Tregs was assessed using a ChIP-Re-ChIP assay, and the results are depicted graphically. (C) Relative permissive (K23 and K27) or repressive (K14 and K18) acetylation of histone-3 was determined using a ChIP assay and depicted graphically using site-specific antibodies. (D) Schematic illustration of the FOXP3-binding site on the CCR4 promoter (−668 bp to −651 bp) with HAT1. (E) After 6 h, the number of FOXP3-ablated/overexpressed Treg cells in the lower chamber of the trans-well plate that migrated in response to recombinant CCL22 was counted and graphically displayed. (F) Flow cytometry was used to determine the percentage of FOXP3-ablated/overexpressed Treg cells that migrated in response to recombinant CCL22 in a trans-well plate (representative plot). The values are the mean ± SD of three sets of independent experiments.