title: The expression of matrix metalloproteinases-9, transforming growth factor-beta1 and transforming growth factor-beta receptor I in human atherosclerotic plaque and their relationship with plaque stability.
abstract: BACKGROUND
  Transforming growth factor-beta (TGF-beta) and matrix metalloproteinases-9 (MMP-9) have been implicated in the pathogenesis of human atherosclerosis but their relationship during lesion progression are poorly understood. The objective of this study was to investigate the expression of MMP-9, TGF-beta1 and TGF-beta receptor I (TbetaR-I) in human atherosclerotic plaque and their relationship and plaque stability.
  
  
  METHODS
  Specimens of human coronary artery atherosclerotic plaques were obtained from 41 patients undergoing coronary endarterectomy, and were paraffin embedded, sectioned at 4 microm intervals then stained with haematoxylin and eosin. They were divided into stable (with no or only little lipid core) and unstable plaque groups (with lipid core size > 40%): the immunohistochemical staining were performed for MMP-9, TGF-beta1 and TbetaR-I.
  
  
  RESULTS
  The expression of MMP-9 in the unstable plaques was much higher than in the stable ones, but the expression of TGF-beta1 was higher in the stable plaques. There was no similar significant difference for TbetaR-I. Correlation analysis showed that there was a negative correlation between the expression of MMP-9 and TGF-beta1 (r = -0.332, P = 0.034 for average areal density; r = -0.373, P = 0.016 for average optical density).
  
  
  CONCLUSIONS
  There were close relationships between MMP-9, TGF-beta1 and plaque stability. Enhanced production of MMP-9 may participate in the formation of unstable plaque, while TGF-beta1 maybe an important stabilizing factor in preventing transition into an unstable plaque phenotype.
authors.affiliation: Department of Cardiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Jiang
authors.forename: He-song
authors.initials: HS
authors.lastname: Zeng
authors.forename: Yi
authors.initials: Y
authors.lastname: Guo
authors.forename: Zhi-bin
authors.initials: ZB
authors.lastname: Zhou
authors.forename: Bing-shan
authors.initials: BS
authors.lastname: Tang
authors.forename: Fu-kang
authors.initials: FK
authors.lastname: Li
mesh_terms: D030201:Activin Receptors, Type I / Q000032:analysis*; D003324:Coronary Artery Disease / Q000378:metabolism* / Q000473:pathology; D005109:Extracellular Matrix / Q000378:metabolism; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000032:analysis*; D008875:Middle Aged; D017346:Protein Serine-Threonine Kinases; D000077293:Receptor, Transforming Growth Factor-beta Type I; D018125:Receptors, Transforming Growth Factor beta / Q000032:analysis*; D016212:Transforming Growth Factor beta / Q000032:analysis*; D053773:Transforming Growth Factor beta1
chemical_list: D018125:Receptors, Transforming Growth Factor beta; C508960:TGFB1 protein, human; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1; D017346:Protein Serine-Threonine Kinases; D030201:Activin Receptors, Type I; D000077293:Receptor, Transforming Growth Factor-beta Type I; D020780:Matrix Metalloproteinase 9