Erk 1/2 differentially regulates the expression from the 1G/2G single nucleotide polymorphism in the MMP-1 promoter in melanoma cells.
Matrix metalloproteinase-1 (MMP-1) breaks down interstitial collagens, a major component of stromal tissue and a barrier for invading tumor cells. The degradation of collagen by MMP-1 may, therefore, provide one mechanism for facilitating tumor invasion and metastasis. Because of the potential for excessive matrix degradation, the expression of MMP-1 is tightly regulated, often by the mitogen-activated protein kinase (MAPK) pathway. The MAPK signal cascade consists of three separate pathways, the extracellular response kinase (ERK), p38 and Jun N-terminal kinase, which target proteins of the AP-1 and ETS families transcription of the gene. The MMP-1 promoter contains a single nucleotide polymorphism (SNP) at -1607 bp, which creates an ETS binding site by the addition of a guanine (5'-GGAT-3' or '2G SNP') compared to the 1G SNP (5'-GAT-3'), and enhances MMP-1 transcription. A2058 melanoma cells represent one tumor cell line that is homozygous for the 2G allele and that produces constitutively high levels of MMP-1. Thus, we used these cells to define the mechanism(s) responsible for this high level of expression. We show that inhibition of ERK 1/2 leads to the repression of MMP-1 transcription, and that both the 2G polymorphism and the adjacent AP-1 site at -1602 bp are necessary for high levels of MMP-1 transcription and for the inhibition of MMP-1 expression by PD098059, a specific ERK inhibitor. Furthermore, restoration of MMP-1 levels after ERK 1/2 inhibition requires de novo protein synthesis of a factor necessary for MMP-1 expression. Thus, this study suggests that the ERK 1/2 pathway targets the 2G polymorphism, and that the continuous synthesis of a protein(s) is necessary for the constitutive expression of MMP-1.
Tower
Grant B
GB
Department of Biochemistry, Dartmouth Medical School, Hanover, NH 03755, USA.
Coon
Charles C
CC
Benbow
Ulrike
U
Vincenti
Matthew P
MP
Brinckerhoff
Constance E
CE
D004789:Enzyme Activation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005419:Flavonoids / Q000494:pharmacology; D015971:Gene Expression Regulation, Enzymologic; D006801:Humans; D007093:Imidazoles / Q000494:pharmacology; D020781:Matrix Metalloproteinase 1 / Q000235:genetics*; D061965:Matrix Metalloproteinase Inhibitors; D008545:Melanoma; D019950:Mitogen-Activated Protein Kinase 1 / Q000037:antagonists & inhibitors / Q000378:metabolism*; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D010766:Phosphorylation; D011110:Polymorphism, Genetic; D011401:Promoter Regions, Genetic / Q000187:drug effects; D011725:Pyridines / Q000494:pharmacology; D015398:Signal Transduction; D014158:Transcription, Genetic; D014407:Tumor Cells, Cultured
D004791:Enzyme Inhibitors; D005419:Flavonoids; D007093:Imidazoles; D061965:Matrix Metalloproteinase Inhibitors; D011725:Pyridines; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D020781:Matrix Metalloproteinase 1; C093642:SB 203580; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one