Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
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Target Concepts:
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Query: EC:3.4.24.3 (
collagenase
)
18,340
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The c-ets1 proteins are transcriptional activators expressed within endothelial cells during blood vessel development in chick embryos. The authors show by in situ hybridization that c-ets1 is transcribed in the endothelia during angiogenesis in human embryos, in granulation tissue, and especially during tumor vascularization. c-ets1 mRNAs were also detected in the fibrocytes of tumor stroma and in the spindle cells of
Kaposi's sarcomas
, regarded as cells of endothelial origin. It has been shown that the c-ets proteins activate transcription through a PEA3 motif that plays a role in the stimulation of transcription of urokinase-type plasminogen-activator (u-PA), stromelysin and
collagenase
genes. The authors demonstrate in vitro that the angiogenic factor TNF alpha increases transiently the amount of both c-ets1 and u-PA mRNA in confluent human umbilical vein endothelial cells. Therefore, the authors suggest that the c-ets1 proteins might regulate the transcription of the genes coding for matrix-degrading proteases, which are necessary for both angiogenesis and tumor invasion.
...
PMID:c-ets1 proto-oncogene is a transcription factor expressed in endothelial cells during tumor vascularization and other forms of angiogenesis in humans. 137 May 94
Basic fibroblast growth factor (bFGF) and human immunodeficiency virus type 1 (HIV-1) Tat protein synergize in inducing angiogenic
Kaposi's sarcoma
-like lesions in mice. Synergy is due to Tat, which enhances endothelial cell growth and type-IV
collagenase
expression in response to bFGF mimicking extracellular matrix proteins. The bFGF, extracellular Tat and Tat receptors are present in HIV-1-associated KS, which may explain the higher frequency and aggressiveness of this form compared to classical
Kaposi's sarcoma
where only bFGF is present.
...
PMID:Synergy between basic fibroblast growth factor and HIV-1 Tat protein in induction of Kaposi's sarcoma. 793 12
Kaposi's sarcoma
(KS) is an angioproliferative disease characterized by proliferating spindle-shaped cells, angiogenesis, and inflammatory cell infiltration. Several lines of evidence suggest that KS is a multifocal cytokine-mediated disease of vascular origin. Because metalloproteinases (MMPs) are important enzymes involved in angiogenesis, we studied their activity in five different KS-derived cell lines and compared these data with those obtained with human umbilical vein endothelial cells (HUVEC). We focused on the activity of the 72- and 92-kd type IV collagenases because these enzymes are thought to play an important role in the process of tumoral invasion. Nonstimulated HUVEC released a weak 72-kd
collagenase
activity and no 92-kd
collagenase
activity, as determined by zymographic analysis. Stimulation of HUVEC with phorbol myristate acetate (PMA) or TNF-alpha increased the 72-kd
collagenase
activity and also induced a 92-kd
collagenase
activity. By contrast, KS-derived cells constitutively released significant 72- and 92-kd
collagenase
activities. The basal release of these enzymes by KS cells was further enhanced by TNF-alpha or PMA. Conversely after in vivo exposure to chemotherapy, KS-derived cells showed a downregulation of the production of MMPS that could be reversed by the addition of TNF or PMA. These results suggest that KS cells have constitutive features of activated cells that have an invasive and metastasizing potential.
...
PMID:Constitutive release of metalloproteinase-9 (92-kd type IV collagenase) by Kaposi's sarcoma cells. 966 96
HIV-1 infection is associated with vascular alterations. This is accompanied by an increased risk of cardiovascular diseases and
Kaposi's sarcoma
, an endothelial cell-derived tumor. We investigated the impact of maternal HIV-1 infection on phenotype and gene expression of endothelial cells in newborns. For this reason endothelial precursor cells and differentiated endothelial cells were isolated from cord blood as well as from umbilical veins and arteries of noninfected infants born to HIV-1-infected (H-group) and noninfected (Ngroup) mothers. No apparent differences in proliferation, capillary formation, and expression of endothelial cell markers were detected in these cells. Interestingly, the expression of matrix metalloproteinase was repressed significantly (X2 analysis, p < 0.002) and consistently at the RNA, the protein, and the secretory levels in the H-group as compared to the N-group. Neither treatment with zidovudine (AZT), mutations in the
matrix metalloproteinase-1
(
MMP-1
) promoter, nor epigenetic changes in the promoter methylation pattern were responsible for the repression of
MMP-1
expression in H-group endothelial cells. The reduced
MMP-1
expression may contribute to the impaired cardiac function that has been observed in children of HIV-1-infected women. Most interestingly, our findings indicate that HIV-1-related effects can be transferred from mother to child in the absence of HIV-1 transmission.
...
PMID:Maternal HIV type 1 infection suppresses MMP-1 expression in endothelial cells of uninfected newborns: nonviral vertical transmission of HIV type 1-related effects. 1638 10
During the past few years, several imaging probes targeting matrix metalloproteinases (MMPs) have been developed. Most of these probes have been validated in animal models. Overall, results derived from most of these studies have been disappointing. Whether or not this relates to shortcomings of the imaging probes used or to the set-up of the reported studies is currently unclear. Firstly, MMPs targeted in these studies,
MMP-1
, -2 and -9, are cell secreted and their expression is known to vary extensively within one tumor type, depending on the stage of development of the tumor and on the presence of naturally occurring TIMPs. Given the lack of data on the levels of MMP expression by incoculated tumor tissue at the time of imaging in most studies reported, it cannot be excluded that the negative results reported are, in fact, false-negative imaging results. Secondly, given that most of the agents used for imaging are intrinsically broad-spectrum agents, their higher affinity for specific subsets of MMPs does not necessarily imply that a positive imaging result also corresponds to overexpression of specific subsets of MMPs, as suggested in some papers published. Accordingly, well-characterized tumor models need to be developed for the purpose of validating currently available, as well as future, MMP-imaging probes. So far, only 111In-DTPA-N-TIMP-2 has been injected in patients, respectively suffering from
Kaposi Sarcoma
. Imaging results obtained with this agent proved disappointing. Imaging results obtained with other MMP-targeting probes in patients are awaited.
...
PMID:Imaging probes targeting matrix metalloproteinases. 1710 15
Matrix metalloproteinases (MMPs) play important roles in cancer invasion, angiogenesis, and inflammatory infiltration.
Kaposi's sarcoma
is a highly disseminated angiogenic tumor of proliferative endothelial cells linked to infection by
Kaposi's sarcoma
-associated herpesvirus (KSHV). In this study, we showed that KSHV infection increased the invasiveness of primary human umbilical vein endothelial cells (HUVEC) in a Matrigel-based cell invasion assay. KSHV-induced cell invasion was abolished by an inhibitor of MMPs, BB-94, and occurred in both autocrine- and paracrine-dependent fashions. Analysis by zymography and Western blotting showed that KSHV-infected HUVEC cultures had increased secretion of
MMP-1
, -2, and -9. KSHV increased the secretion of MMP-2 within 1 h following infection without upregulating its mRNA expression level. In contrast, the secretion of
MMP-1
and -9 was not increased until 6 h after KSHV infection and was correlated with the upregulation of their mRNA expression levels. Promoter analysis by reporter assays and electrophoretic mobility shift assays identified an AP-1 cis-element as the dominant KSHV-responsive site in the
MMP-1
promoter. Together, these results suggest that KSHV infection modulates the production of multiple MMPs to increase cell invasiveness and thus contributes to the pathogenesis of KSHV-induced malignancies.
...
PMID:Kaposi's sarcoma-associated herpesvirus infection promotes invasion of primary human umbilical vein endothelial cells by inducing matrix metalloproteinases. 1744 15
Murine gammaherpesvirus 68 (MHV-68) is a natural pathogen of rodents closely related to the human gammaherpesviruses
Kaposi's sarcoma
-associated herpesvirus and EBV. Following intranasal infection, the virus replicates in the lung epithelium prior to establishing latent infection in lymphoid tissue. Infection of mice deficient in IFN-gammaR signaling (IFN-gammaR-/-) results in a multiple organ fibrosis, in which the spleen is severely affected. We show here that by Day 12 postinfection, prior to development of fibrosis in the spleens of IFN-gammaR-/- mice, different subsets of splenic macrophages (Mvarphis) are morphologically activated and enter latently infected germinal centers (GCs). Mvarphis coexpressing arginase I (ARG1), a marker of alternative activation of Mvarphis, and murine Mvarphi markers F4/80, ER-TR9, and MOMA-1 are found in GCs of IFN-gammaR-/- mice but not of wild-type mice. Quantitative RT-PCR of spleen RNA confirms induction of ARG1 and in addition, shows up-regulation of found in inflammatory zone 1/resistin-like molecule-alpha, tissue inhibitor of
metalloproteinase-1
, matrix metalloproteinase-12, fibronectin, and factor XIIIA in IFN-gammaR-/- mice. In contrast, inducible NO synthase, associated with classical Mvarphi activation, is up-regulated following infection of wild-type mice but not IFN-gammaR(-/-) mice. Concomitant with the aaMvarphis, transcription of the Th2 cytokines IL-13, IL-21, and IL-5 is up-regulated. Thus, in the absence of IFN-gammaR signaling, MHV-68 initiates a Th2 immune response, leading to alternative activation of macrophages and induction of fibrosis. This system provides an important model for studying the pathogenesis of fibrosis initiated by a latent herpesvirus infection.
...
PMID:Murine gammaherpesvirus-induced fibrosis is associated with the development of alternatively activated macrophages. 1843 82
Traditionally, the dental profession has primarily treated periodontitis using a mechanical/surgical, rather than a pharmaceutical, approach. However, based on experiments several decades ago which demonstrated that tetracyclines, unexpectedly, inhibit collagen- and bone-destructive mammalian-derived enzymes (e.g. the collagenases), and through non-antibiotic mechanisms, the concept of host-modulation therapy (HMT) was developed. Accordingly, two drug-development strategies evolved: (i) the development of non-antimicrobial formulations of doxycycline; and (ii) the chemical modification of tetracyclines to eliminate their antibiotic activity but retain (or even enhance) their anti-
collagenase
properties. Regarding the latter, these chemically modified tetracyclines (CMTs) showed efficacy in vitro, in animal models of periodontal (and relevant systemic) disease, and in preliminary clinical trials on patients with
Kaposi's sarcoma
(however, at the high doses used, photosensitivity was a significant side-effect). In the first strategy, subantimicrobial-dose doxycycline (SDD) demonstrated safety and efficacy in human clinical trials and was approved by the U S Food and Drug Administration (U S FDA) and in other countries for the treatment of periodontitis (20 mg, twice daily, i.e. once every 12 hours) adjunctive to scaling and root planing, and for chronic inflammatory skin diseases (40-mg sustained-release 'beads'). SDD also showed efficacy in patients with systemic diseases relevant to periodontitis, including diabetes mellitus and arthritis, and in postmenopausal women with local and systemic bone loss. Importantly, long-term administration of SDD, of up to 2 years, in clinical trials did not produce antibiotic side-effects. SDD (and in the future, new HMTs, such as low-dose CMT-3, resolvins and chemically modified curcumins) may shift the paradigm of periodontal therapy from a predominantly surgical approach to the greater use of medicinal/pharmacologic strategies, ultimately to benefit larger numbers of patients.
...
PMID:Non-antibacterial tetracycline formulations: host-modulators in the treatment of periodontitis and relevant systemic diseases. 2700 89