SATB1 binds to CDKN1A promoter and regulates its transcription. (A) PCR products after Chromatin immunoprecipitation (ChIP) with anti-SATB1 antibody showed enrichment of SATB1 in a region within the CDKN1A promoter (–520 to −368 relative to TSS, 152 bp) in Mac-1 cells. M, DNA marker; input, cell lysate before immunoprecipitation; S, cell lysate immunoprecipitated with anti-SATB1 antibody; +, positive control cell lysate immunoprecipitated with anti-RNA polymerase II; –, negative control cell lysate immunoprecipitated with normal mouse IgG. (B) The CDKN1A promoter (WT) and its mutants with deficient SATB1 consensus binding site are shown schematically. Dual luciferase assay demonstrated that the luciferase (LUC) activity of the CDKN1A promoter mutants were significantly higher than that of wide-type in Mac-1 cells. *P < .05. Each experiment was repeated 2 times with 3 biological replicates.