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Updated: Jul 18, 2026
Long-term Intravital Immunofluorescence Imaging of Tissue Matrix Components with Epifluorescence and Two-photon Microscopy
Published on: April 22, 2014
Expression of vascular endothelial growth factor a, matrix metalloproteinase 9 and extravascular matrix patterns in
Afsun Sahin1, Hayyam Kiratli, Gaye Guler Tezel
1Department of Ophthalmology, Ocular Oncology Service, Hacettepe University School of Medicine, Ankara, Turkey.
Purpose:
It was the aim of this study to assess the expression of vascular endothelial growth factor (VEGF)-A, matrix metalloproteinase (MMP)-9 and extravascular matrix patterns (EMPs) in iris and ciliary body melanomas and their correlations with histopathologic parameters.
Methods:
The study was conducted on 3 iris and 15 ciliary body melanomas. All tumors were subjected to immunohistochemical techniques for VEGF-A and MMP-9 expressions, the presence of EMPs was assessed, and routine paraffin sections were stained with hematoxylin-eosin. Cell type, tumor localization, degree of pigmentation, necrosis, mitotic index, lymphocytic infiltration and sclera invasion were analyzed using light microscopy.
Results:
The mean patient age at the time of treatment was 43 years (range 19-69, median 39.5); 10 (55.6%) patients were males and 8 (44.4%) females. Histopathological cell types were spindle cells in 55.6%, mixed cells in 16.7%, and epithelioid cell types in 27.8% of tumors. Positive reaction for VEGF-A and MMP-9 was present in 66.7 and 72.3% of the tumors, respectively. Microvascular loops and/or networks were seen in 33.4% of the tumors, with the remaining 66.7% of tumors displaying one or more of the other patterns. Metastatic disease developed in only 1 patient during follow-up. Tumor cell type, tumor size, mitotic rate, degree of pigmentation and EMPs were not correlated with metastasis.
Conclusions:
This study suggests that VEGF-A and MMP-9 were positive in the majority of iris and ciliary body melanomas. No correlation was found between VEGF-A and MMP-9 immunoreactivity and EMPs and occurrence of metastases in cases of anterior uveal melanoma.
Insights
Vascular endothelial growth factor (VEGF)-A and matrix metalloproteinase (MMP)-9 are frequently expressed in iris and ciliary body melanomas. However, their presence, along with extravascular matrix patterns (EMPs), did not correlate with metastasis in these anterior uveal melanomas.
Area of Science:
- Ophthalmology
- Oncology
- Pathology
Background:
- Anterior uveal melanomas, including iris and ciliary body melanomas, are rare ocular tumors.
- Understanding the molecular markers associated with melanoma progression is crucial for predicting patient outcomes.
Purpose of the Study:
- To evaluate the expression of vascular endothelial growth factor (VEGF)-A, matrix metalloproteinase (MMP)-9, and extravascular matrix patterns (EMPs) in iris and ciliary body melanomas.
- To investigate the correlation between these markers and histopathological parameters, including metastasis.
Main Methods:
- Immunohistochemical analysis of VEGF-A and MMP-9 expression in 18 iris and ciliary body melanoma tumors.
- Assessment of EMPs and routine hematoxylin-eosin staining.
- Analysis of histopathological features such as cell type, pigmentation, mitotic index, and sclera invasion.
Main Results:
- VEGF-A and MMP-9 expression was detected in 66.7% and 72.3% of tumors, respectively.
- Various EMPs were observed in 66.7% of tumors.
- Only one patient developed metastasis during follow-up, and no significant correlation was found between VEGF-A, MMP-9, EMPs, and metastasis.
Conclusions:
- VEGF-A and MMP-9 are commonly expressed in anterior uveal melanomas.
- The expression of VEGF-A, MMP-9, and EMPs does not appear to be predictive of metastasis in these tumors.
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