p53 Down-regulates Human Matrix Metalloproteinase-1 (Collagenase-1) Gene Expression

Abstract

We hypothesize that the abnormality of p53 seen in RA synovium may contribute to joint degeneration through the regulation of human matrix metalloproteinase-1 (hMMP-1, collagenase-1) gene expression. Transcription assays were performed with luciferase reporters driven by the promoter of the hMMP-1 gene or by a minimal promoter containing tandem repeats of the consensus binding sequence for activator protein-1, cotransfected with p53-expressing plasmids. The results revealed that (i) wild-type (wt) p53 down-regulated the promoter activity of hMMP-1 in a dose-dependent fashion; (ii) four of six p53 mutants (commonly found in human cancers) lost this repression activity; and (iii) this p53 repression activity was mediated at least in part by the activator protein-1 sites found in the hMMP-1 promoter. These findings were further confirmed by Northern analysis. The down-regulation of hMMP-1 gene expression by endogenous wtp53 was shown by treatment of U2-OS cells, a wt-p53-containing osteogenic sarcoma line, and Saos-2 cells, a p53-negative osteogenic sarcoma line, with etoposide, a potent inducer of p53 expression. p53, activated by etoposide, appears to block hMMP-1 promoter activity induced by etoposide in U2-OS cells. In summary, we have shown for the first time that the hMMP-1 gene is a p53 target gene, subject to p53 repression. Because MMP-1 is principally responsible for the irreversible destruction of collagen in articular tissue in RA, abnormality of p53 may contribute to joint degeneration through the regulation of MMP-1 expression.Rheumatoid arthritis (RA) 1 is marked by destruction of the extracellular matrix and it is believed that, among other factors, matrix metalloproteinases (MMPs) play an important role in mediating the degradation of connective tissue matrix components such as collagens and proteoglycans (4, 5). Collagenase-1 (MMP-1), stromelysin (MMP-3), gelatinase A and B (MMP-2 and MMP-9), and collagenase-3 (MMP-13) are all present at significantly elevated levels in cartilage, synovial membranes, and synovial fluid of patients with RA (6 -8). The synovium produces substantial amounts of MMP-1, the major matrix metalloproteinase involved in the degradation of interstitial collagens, specifically, types I-III. MMP-1 expression has been shown to be stimulated by native collagen type I and collagen fragments, phorbol esters, growth factors, and cytokines such as interleukin 1␤ (IL-1␤) and tumor necrosis factor-␣ (9 -12). The activity of MMP-1 is stringently regulated at three levels: the promoter, the activation of proenzyme, and the inhibition of active enzyme. The activator protein-1 (AP-1) binding sites found in the promoters of human collagenase have been shown to be critical to the expression of human collagenase (13-16).The protein product of the p53 tumor suppressor gene plays a very important role in cell growth control, DNA repair, and apoptosis (17). It has been proposed that p53 acts as an "emergency brake" inducing G1 arrest and apoptosis after DNA damage, either by halting cell divi...

Association of a single nucleotide polymorphism in the matrix metalloproteinase‐1 promoter with glioblastoma

“…For example, the p53 status of the tumor could influence the levels of MMP-1 as it has been shown that wild-type p53 suppresses MMP-1 transcription. [31][32][33] Brinckerhoff et al 34 propose a model that addresses the likelihood of the 2G allele contributing to pathologic processes. The model states that several molecular events must take place in addition to the presence of the 2G allele.…”

Overexpression of the p53-inducible brain-specific angiogenesis inhibitor 1 suppresses efficiently tumour angiogenesis

“…In addition, BAI1 inhibition of interstitial collagenase expression may prevent the dissolution of the extracellular matrix. Matrix metalloproteinase-1 (MMP-1) was found in other cells to be a p53-target gene, subject to p53 repression, mediated in part by associated protein 1 (Sun et al, 1999). We are currently investigating the MMP-1 protein level and activity in relation to BAI1 and p53 expression.…”

IL-6 and Matrix Metalloproteinase-1 Are Regulated by the Cyclin-Dependent Kinase Inhibitor p21 in Synovial Fibroblasts

“…These data suggest that a subset of synovial fibroblasts may possess an inactive form of p53. Overexpression of plasmids encoding the p53 mutants found in RA synovium suppresses wild-type p53 function, as indicated by the induction of known p53-regulated genes, including IL-6 (53,54) and MMP-1 (55,56), which are normally inhibited by wild-type p53. Additionally, mice deficient in p53 display enhanced experimental arthritis, elevated levels of IL-6 in the synovium, and increased spontaneous MMP-13 expression compared with wildtype mice (57).…”

“…Thus, p21-deficeint synovial fibroblasts behave similarly to the RA synovial fibroblasts that lack p53 or express the mutant forms of p53. Furthermore, ectopic expression of p21 or overexpression of wild-type p53 reduces IL-6 and MMP-1 expression in RA synovial fibroblasts (53)(54)(55)(56)58). Collectively, these data suggest that p21 may be one of the nodal points through which p53 inhibits cytokines and MMPs (Fig.…”