Role of Sox-9, ER81 and VE-Cadherin in Retinoic Acid-Mediated Trans-Differentiation of Breast Cancer Cells
Figure 5
Sox-9 and ER81 bound to the human VE-cadherin promoter.
(A) Sox-9 (5′-AACAAT-3′) and two ER81 (5′-GGAA-3′) binding sites were present between −114 bp and −86 bp in the human VE-cadherin gene. (B) EMSA with various 32P-labeled probes. With wild type probe, two major bands (arrows) were detected, and the formation of these complexes was increased by 9-cis-RA (1 µM). Complex formation was diminished by mutation of the Sox-9 binding site and 3′ ETV binding site but was not affected by mutation in the 5′ ETV binding site. (C) Sox-9 binds to VE-cadherin promoter: (left) competition experiment with cold WT and Sox-9 mutant probes. (right) effect of Sox-9 antibody on 9-cis-RA-induced DNA/protein complex formation. (D) Both Sox-9 and ER81 antibodies inhibited 9-cis-RA-dependent complex formation. WT probe and 5′-ETV mutant probe were used and compared. Note that 5′-ETV probe showed enhanced DNA/protein complex formation, which was reduced by either, Sox-9 antibody, ER81 antibody, and their combination. Data is representative of three independent experiments.