A regulatory element that mediates co-operation between a PEA3-AP-1 element and an AP-1 site is required for phorbol ester induction of urokinase enhancer activity in HepG2 hepatoma cells.

Abstract

We have characterized a transcriptional enhancer of the human urokinase‐type plasminogen activator (uPA) gene and found a regulatory element required for co‐operation between a PEA3‐‐AP‐1 element and an AP‐1 site in the enhancer. We designated this regulatory element co‐operation mediator (COM). Both the PEA3‐‐AP‐1 element, the AP‐1 site and the COM are required for efficient phorbol ester induction of transcription from the uPA promoter in the HepG2 hepatoma cell line. We show that the COM is also required for co‐operation between the PEA3‐‐AP‐1 element and a glucocorticoid response element, both in the presence or absence of TPA, indicating that the COM is generally capable of mediating synergism between inducible enhancer elements. The COM contains multiple overlapping binding sites for nuclear proteins, designated uPA enhancer factors 1–4 (UEF‐1‐4). We have identified putative binding sites for UEF‐1, −2 and −3. The UEF‐1 and −3 sites in the uPA enhancer are highly conserved between species. We demonstrate the binding of UEF‐3 to the NIP element, a previously characterized regulatory element in the human interleukin‐3 and stromelysin promoters, suggesting that this factor plays a role in regulation of a variety of genes.

Expression of the ets-1 Proto-Oncogene in Human Colorectal Carcinoma

“…We believe that Ets-1 protein is overproduced in the cytoplasm and bound to DNA in the nucleus of colorectal carcinoma cells. Recently, it was shown that Ets-1 protein regulates the gene expression of some cytokines and peptides, such as Fos and Jun (36), integrin (37), stromelysin (38), u-PA (5) and MMP-1 (12). The expression of these substances also has been observed in colorectal carcinoma cells (39 -41), and they may play important roles in tumor invasion and progression.…”

“…Matrix metalloproteinases and plasminogen activator have been proposed to participate in the metastatic cascade (9 -11). Ets-1 protein interacts with the urokinase-type plasminogen ac-tivator (u-PA) gene enhancer and with the promoters of the stromelysin-1 and matrix metalloproteinase-1(MMP-1) genes (5,12). Ets-1, therefore, is suggested to regulate increased tumor invasion by activating the expression of u-PA, stromelysin and collagenase.…”

Cooperation between AP1 and PEA3 sites within the progression elevated gene-3 (PEG-3) promoter regulate basal and differential expression of PEG-3 during progression of the oncogenic phenotype in transformed rat embryo cells

“…PEA3 proteins interact with an *10 base pair DNA sequence in the promoters of target genes resulting in regulation of transcription (Macleod et al, 1992;Seth et al, 1992;Wasylyk et al, 1993). Putative candidate PEA3 target genes include proteinases required for degradation of the extracellular matrix, including the serine urokinasetype plasminogen activator (Nerlov et al, 1992) and matrix metalloproteinases gelatinase B, interstitial collagenase, stromelysin-3 and matrilysin (Matrisian and Bowden, 1990;Matrisian, 1994;Higashino et al, 1995), which represent important factors contributing to cancer metastasis (Liotta et al, 1991;Kohn and Liotta, 1995). Many of these extracellular matrix degrading genes also contain AP1 sites in their promoters (Angel and Karin, 1991;Karin et al, 1997).…”

“…Cooperation between AP1 and PEA3 sites in regulating several cellular promoters have been documented. These include, serum growth factor response of the tissue inhibitor of metalloproteinases-1 (TIMP-1) gene (Edwards et al, 1992) and 12-0-tetradecanoylphorbol 13-acetate (TPA), ®broblast growth factor-2 (FGF-2) and macrophage colony-stimulating factor induction of the urokinase-type plasminogen activator gene (Nerlov et al, 1992;Stacey et al, 1995;De Cesare et al, 1996;D'Orazio et al, 1997). Moreover, PEA3 and AP1 elements are also present in the promoters of the stromelysin and collagenase genes (Gutman and Wasylyk, 1990;Sirum-Conolly and Brinckerho , 1991) and these elements provide targets for transcriptional activation by speci®c transforming oncogenes (Wasylyk et al, 1989(Wasylyk et al, , 1993.…”

HER2/Neu and the Ets transcription activator PEA3 are coordinately upregulated in human breast cancer

“…The unregulated expression of these enzymes has been associated with the propensity of tumor cells to metastasize (Kohn and Liotta, 1995). For example, PEA3 binding sites occur in the promoters of the serine proteinase urokinase-type plasminogen activator (Rorth et al, 1990;Nerlov et al, 1992) as well as the matrix metalloproteinases (MMP) gelatinase B (92 kDa type IV collagenase or MMP-9), interstitial collagenase (MMP-1), stromelysin-1 (transin or MMP-3), stromelysin-2 (MMP-10), stromelysin-3 (MMP-11) and matrilysin (pump-1 or MMP-7) (Matrisian, 1994;Higashino et al, 1995). PEA3 directly activates transcription from the MMP-1, MMP-9 and MMP-11 promoters (Higashino et al, 1995).…”