Figure 3
From: HIF-1α stimulates aromatase expression driven by prostaglandin E2 in breast adipose stroma
HIF-1α is necessary and acts cooperatively with CREB1 to induce PII activity in response to PGE 2 . (A) A putative HRE (italic) was found to overlap with the proximal CRE (boxed) of aromatase PII. (B) Reporter assays demonstrated that mutation of the proximal CRE of aromatase PII inhibited the HIF-1α/DMOG-mediated effect on PII activity. (C) PII activity was significantly increased in HIF-1α transfected cells, treated with DMOG and PGE2, and co-transfection with CREB1 resulted in a further increase in PII activity compared to cells transfected with either HIF-1α or CREB1 alone. Knockdown of HIF-1α (E) using siRNA significantly reduced PII activity (D) and aromatase transcript expression (F) and suppressed the PGE2-mediated effect on PII activity (D). β-gal, β-galactosidase activity; RLU, relative luciferase units. N = 3, all experiments repeated twice.