Matrix metalloproteinases in human choroidal neovascular membranes excised following verteporfin photodynamic therapy
- Olcay Tatar1,
- Annemarie Adam2,
- Kei Shinoda3,
- Tillmann Eckert4,
- Gábor B Scharioth5,
- Micheal Klein6,
- Efdal Yoeruek1,
- Karl Ulrich Bartz-Schmidt1,
- Salvatore Grisanti1
- 1University Eye Hospital, Centre for Ophthalmology, Eberhard-Karls University, Tuebingen, Germany
- 2Department of Pathology, Eberhard-Karls University, Tuebingen, Germany
- 3Laboratory of Visual Physiology, National Institute of Sensory Organs, Tokyo, Japan
- 4Augenklinik der Staedtischen Kliniken, Frankfurt am Main, Germany
- 5Augenzentrum Recklinghausen, Germany
- 6Augenklinik Tausendfensterhaus, Duisburg, Germany
- Professor Dr Salvatore Grisanti, University Eye Hospital, Centre for Ophthalmology, Eberhard-Karls University, Tuebingen, Germany, Schleichstrasse 12-15, 72076 Tuebingen, Germany; Salvatore.Grisanti{at}med.uni-tuebingen.de
- Accepted 8 April 2007
- Published Online First 2 May 2007
Abstract
Aim: To evaluate expression of proangiogenic matrix metalloproteinases (MMP) 2 and 9 at distinct intervals after verteporfin photodynamic therapy (PDT) in human choroidal neovascular membranes (CNV) secondary to age-related macular degeneration (AMD).
Methods: Retrospective review of an interventional case series of 49 patients who underwent removal of CNV. Twenty-six patients were treated with PDT 3 to 383 days prior to surgery. Twenty-three CNV without previous treatment were used as controls. CNV were stained for CD34, cytokeratin 18, endostatin, MMP-2 and MMP-9 by immunohistochemistry.
Results: CNV without previous therapy disclosed MMP-2, MMP-9 in RPE–Bruch’s membrane, vessels and stroma in different intensities. Three days after PDT, MMP-9 expression was significantly weaker in stroma (p = 0.0019). Endostatin was significantly reduced in vessels (p<0.001). At longer post-PDT intervals, a significant increase of MMP-9 in stroma (p = 0.037) and of endostatin in RPE–Bruch’s membrane (p = 0.02), vessels (p = 0.005) and stroma (p<0.001) were disclosed. No significant changes in MMP-2 expression were detected.
Conclusions: PDT induced an early, temporary decrease in MMP-9 and endostatin expression. At longer intervals, MMP-9 increase is possibly associated with the angiogenic process responsible for recurrence after PDT. MMP-9, however, acts as a double-edged sword by concomitant induction of endostatin, an endogenous inhibitor of angiogenesis.
Footnotes
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Funding: This work was supported by grants from the Vision 100 Foundation and Jung Foundation.
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Competing interests: None.
- Abbreviations:
- AMD
-
age-related macular degeneration
- CNV
-
choroidal neovascular membranes
- EC
-
endothelial cell
- ECM
-
extracellular matrix
- MMP
-
matrix metalloproteinases
- PDT
-
photodynamic therapy
- PEDF
-
pigment epithelium-derived factor
- VEGF
-
vascular endothelial growth factor









