Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:1.14.11.2 (prolyl hydroxylase)
 1,814 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Antibodies were raised against seven major matrix metalloproteinases: stromelysin-1 (MMP-3), stromelysin-2 (MMP-10), stromelysin-3 (MMP-11), interstitial collagenase (MMP-1), M(r) 72,000 type IV collagenase (72 kDa type IV collagenase, MMP-2), M(r) 92,000 type IV collagenase (92 kDa type IV collagenase, MMP-9) and matrilysin (PUMP, MMP-7) as well as against prolyl 4-hydroxylase, to study the expression of these collagenolytic enzymes in normal liver in relation to the activity of collagen synthesis. Tissue samples of four normal human livers, three hepatocellular carcinomas and one cholangiocellular carcinoma were analysed. In normal liver we found expression of stromelysin-1, stromelysin-3, interstitial collagenase, M(r) 72,000 and M(r) 92,000 type IV collagenases and varying expression of prolyl 4-hydroxylase. Stromelysin-2 was inconsistently detectable; matrilysin was not found. In hepatocellular carcinoma the expression pattern of matrix metalloproteinases showed only minor changes compared with the normal tissue; stronger signals than in normal tissue were seen for stromelysin-1, and stromelysin-2 was also strongly positive. M(r) 72,000 and M(r) 92,000 type IV collagenases and interstitial collagenase were less strongly expressed; stromelysin-3 was unchanged. Expression of prolyl 4-hydroxylase was also increased compared with normal liver. Matrilysin was only seen in cholangiocellular carcinoma, which showed a completely different pattern of matrix metalloproteinase expression. Our results show that metalloproteinases are expressed in human liver with much greater abundance than previously described. Their expression pattern is not changed fundamentally in hepatocellular carcinoma but is completely different from that of other tumour tissues such as cholangiocellular carcinoma.
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PMID:Expression pattern of matrix metalloproteinases in human liver. 763 22

The collagen alterations in the vascular wall remodeled by hemodynamic change were investigated by electron microscopy and immunohistochemistry. The left anterior descending coronary artery (LAD) without a myocardial bridge (MB) showed both lower matrix metalloproteinase-1 (MMP-1) expression and a smaller extent of spiraled collagen (SC) distribution than the LAD wall with MB, in which the intima was influenced by high shear stress. In the wall of the varicose great saphenous vein (GSV) the expression of MMP-1 was lower, while the expression of prolyl 4-hydroxylase was higher, than in the normal GSV. The extent of SC distribution in the intima and media of the varicose GSV was smaller than that in the normal GSV. An analogous difference in results was demonstrated between the portal vein (PV) of patients with liver cirrhosis and normal PV. However, the levels of expression of MMP-2, MMP-9 and tissue inhibitors of MMP (TIMPs) in these pathologic vessels were not different from those in the corresponding normal vessels. The results indicate that hemodynamic forces such as shear stress and increased intravascular blood pressure contribute to the collagen alterations in the vascular wall, which may lead to vascular wall remodeling.
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PMID:Collagen alteration in vascular remodeling by hemodynamic factors. 1099 74

Hypoxia-inducible factor-1 (HIF-1) plays an important role in stress-responsive gene expression. Although primarily sensitive to hypoxia, HIF-1 signaling can be regulated by a number of stress factors including metabolic stress, growth factors and molecules present in the extracellular matrix (ECM). Degradation of ECM by metalloproteinases (MMP) is important for tumor progression, invasion and metastasis. ECM is predominantly collagen, and the imino acids (Pro and HyPro) comprise 25% of collagen residues. The final step in collagen degradation is catalyzed by prolidase, the obligate peptidase for imidodipeptides with Pro and HyPro in the carboxyl terminus. Defective wound healing in patients with inherited prolidase deficiency is associated with histologic features of angiopathy suggesting that prolidase may play a role in angiogenesis. Because HIF-1 alpha is central to angiogenesis, we considered that prolidase may modulate this pathway. To test this hypothesis, we made expression constructs of human prolidase and obtained stable transfectants in colorectal cancer cells (RKO). Overexpression of prolidase resulted in increased nuclear hypoxia inducible factor (HIF-1 alpha) levels and elevated expression of HIF-1-dependent gene products, vascular endothelial growth factor (VEGF) and glucose transporter-1 (Glut-1). The activation of HIF-1-dependent transcription was shown by prolidase-dependent activation of hypoxia response element (HRE)-luciferase expression. We used an oxygen-dependent degradation domain (ODD)-luciferase reporter construct as a surrogate for HIF-1 alpha as an in situ prolyl-hydroxylase assay. Since this reporter is degraded by VHL-dependent mechanisms, the increased levels of luciferase observed with prolidase expression reflected the decreased HIF-1 alpha prolyl hydroxylase activity. Additionally, the differential expression of prolidase in 2 breast cancer cell lines showed prolidase-dependent differences in HIF-1 alpha levels. These findings show that metabolism of imidodipeptides by prolidase plays a previously unrecognized role in angiogenic signaling.
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PMID:Extracellular matrix and HIF-1 signaling: the role of prolidase. 1799 10