Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.24.17 (MMP-3)
 3,419 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The use of the mouse skin multistage model of carcinogenesis has aided our understanding of critical target genes in chemical carcinogenesis. The mutagenic activation of the Harvey-ras proto-oncogene has been found to be an early event associated with the initiation of mouse skin tumors by the polycyclic aromatic hydrocarbon 7,12 dimethylbenz[alpha]anthracene and the pure initiator ethyl carbamate (urethane). In contrast to chemical initiation of mouse skin tumors, ionizing radiation-initiated malignant skin tumors have been shown to possess distinct non-ras transforming gene(s). Differential screening of cDNA libraries made from chemically initiated malignant skin tumors has been used to identify a number of cellular gene transcripts that are overexpressed during mouse skin tumor progression. These differentially expressed genes include beta-actin, ubiquitin, a hyperproliferative keratin (K6), a gene whose product is a member of a fatty acid or lipid-binding protein family, and a gene called transin or stromelysin. The overexpression of the stromelysin gene, which encodes a metalloproteinase that degrades proteins in the basement membrane, is hypothesized to play a functional role in malignant tumor cell invasion and metastasis. We believe that the cloning, identification, and characterization of gene sequences that are differentially expressed during tumor progression could lead to the discovery of gene products that either play functional roles in skin tumor progression or in the maintenance of various progressive tumor phenotypes.
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PMID:Differential gene expression during multistage carcinogenesis. 177 1

Retinoids are important regulators of epithelial differentiation. AGN 193109 is a high-affinity antagonist and inverse agonist for the nuclear retinoic acid receptors (RARs). Paradoxically, both AGN 193109 and retinoid agonists inhibit the expression of the differentiation marker MRP-8 in normal human keratinocytes (NHKs). TTNPB, an RAR agonist, and AGN 193109 mutually antagonize MRP-8 inhibition at both mRNA and protein levels. We find that this antagonism, which is greatest at an AGN 193109:TTNPB ratio of about 10:1, is absent when either compound is in significant excess. The potent RARalpha-specific agonist, AGN 193836, has no effect on MRP-8 regulation. These data indicate that inverse agonists and agonists suppress MRP-8 in NHKs through RARgamma using distinct and mutually inhibitory mechanisms. The activity of AGN 193109 on MRP-8 is cell type specific. In differentiating ECE16-1 cervical cells, TTNPB inhibits while AGN 193109 induces MRP-8 mRNA levels. The effect of AGN 193109 on genes inhibited by retinoid agonists in NHKs is also selective; expression of the differentiation markers transglutaminase 1 and keratin 6 is not down-regulated by AGN 193109 whereas stromelysin-1 expression is suppressed. These results show a complex gene and cell context-specific interplay between agonist and inverse agonist for the regulation of gene expression.
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PMID:Cell type and gene-specific activity of the retinoid inverse agonist AGN 193109: divergent effects from agonist at retinoic acid receptor gamma in human keratinocytes. 1031 95

Transforming growth factor-alpha (TGFalpha) and fibroblast growth factor-7 (FGF7) exhibit distinct expression patterns in the mammary gland. Both factors signal through mitogen-activated kinase/extracellular regulated kinase-1,2 (MAPK(ERK1,2)); however, their unique and/or combined contributions to mammary morphogenesis have not been examined. In ex vivo mammary explants, we show that a sustained activation of MAPK(ERK1,2) for 1 h, induced by TGFalpha, was necessary and sufficient to initiate branching morphogenesis, whereas a transient activation (15 min) of MAPK(ERK1,2), induced by FGF7, led to growth without branching. Unlike TGFalpha, FGF7 promoted sustained proliferation as well as ectopic localization of, and increase in, keratin-6 expressing cells. The response of the explants to FGF10 was similar to that to FGF7. Simultaneous stimulation by FGF7 and TGFalpha indicated that the FGF7-induced MAPK(ERK1,2) signaling and associated phenotypes were dominant: FGF7 may prevent branching by suppression of two necessary TGFalpha-induced morphogenetic effectors, matrix metalloproteinase-3 (MMP-3/stromelysin-1), and fibronectin. Our findings indicate that expression of morphogenetic effectors, proliferation, and cell-type decisions during mammary organoid morphogenesis are intimately dependent on the duration of activation of MAPK(ERK1,2) activation.
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PMID:The MAPK(ERK-1,2) pathway integrates distinct and antagonistic signals from TGFalpha and FGF7 in morphogenesis of mouse mammary epithelium. 1744 57

Glucocorticoids (GCs) play a key role in skin homeostasis and stress responses acting through the GC receptor (GR), which modulates gene expression by DNA binding-dependent (transactivation) and -independent (transrepression) mechanisms. To delineate which mechanisms underlie the beneficial and adverse effects mediated by GR in epidermis and other epithelia, we have generated transgenic mice that express a mutant GR (P493R, A494S), which is defective for transactivation but retains transrepression activity, under control of the keratin 5 promoter (K5-GR-TR mice). K5-GR-TR embryos exhibited eyelid opening at birth and corneal defects that resulted in corneal opacity in the adulthood. Transgenic embryos developed normal skin, although epidermal atrophy and focal alopecia was detected in adult mice. GR-mediated transrepression was sufficient to inhibit keratinocyte proliferation induced by acute and chronic phorbol 12-myristate 13-acetate exposure, as demonstrated by morphometric analyses, bromodeoxyuridine incorporation, and repression of keratin 6, a marker of hyperproliferative epidermis. These antiproliferative effects were mediated through negative interference of GR with MAPK/activator protein-1 and nuclear factor-kappaB activities, although these interactions occurred with different kinetics. However, phorbol 12-myristate 13-acetate-induced inflammation was only partially inhibited by GR-TR, which efficiently repressed IL-1beta and MMP-3 genes while weakly repressing IL-6 and TNF-alpha. Our data highlight the relevance of deciphering the mechanisms underlying GR actions on epithelial morphogenesis as well as for its therapeutic use to identify more restricted targets of GC administration.
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PMID:Transrepression function of the glucocorticoid receptor regulates eyelid development and keratinocyte proliferation but is not sufficient to prevent skin chronic inflammation. 1817 58

In this study, we evaluated whether the forced expression of beta6 integrin would modulate the epithelial to mesenchymal transition (EMT). When the full length beta6 integrin was expressed in poorly invasive squamous cell carcinoma SCC9 cells, the resulting SCC9/6 cells acquired a fibroblast-like morphology, increased expression of the mesenchymal marker vimentin and reduced expression of the epithelial markers keratin and E-cadherin. SCC9beta6D1 cells, which express a truncated form of beta6 subunit lacking the C-terminal 11 amino acids (AA), retained their epithelial morphology and did not alter vimentin or E-cadherin expression. This suggests that the full-length beta6 subunit can induce EMT in oral SCC cells. We previously showed that expression of beta6 increases both MMP-3 activation and tenascin-C expression and we now show that both molecules are MEK dependent. These results also demonstrate that the terminal 11 AA of beta6 contain information important for establishing an epithelial to mesenchymal transition.
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PMID:The role of the integrin alpha v beta6 in regulating the epithelial to mesenchymal transition in oral cancer. 1933 Nov 41