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MLH1 and MSH2 expression in pterygia.
Barbara G Schneider1, Deshdeepak Sahni, Juan C Torres
1Division of Gastroenterology, Department of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232, USA. barbara.schneider@vanderbilt.edu
Cornea
|April 26, 2007
Summary
This study investigated pterygia for microsatellite instability (MSI), a genetic defect common in cancers. Researchers found no evidence of MSI or loss of heterozygosity in pterygia, suggesting these conditions are not present.
Area of Science:
- Ophthalmology
- Molecular Biology
- Oncology
Background:
- Pterygia, a common eye condition, share genetic similarities with cancers.
- Microsatellite instability (MSI) is a known genetic defect in cancers.
Purpose of the Study:
- To investigate pterygia for genetic defects, specifically microsatellite instability (MSI) and loss of heterozygosity (LOH).
- To examine pterygia for proteins typically deficient in MSI-positive adenocarcinomas.
- To test pterygia DNA for microsatellite instability using Bethesda convention markers.
Main Methods:
- Immunohistochemistry was used to assess MLH1 and MSH2 protein expression in 13 pterygia.
- Microsatellite analysis was performed on pterygial DNA using 5 standard Bethesda markers.
- DNA mismatch repair proteins MLH1 and MSH2 were the focus of protein analysis.
Main Results:
- MLH1 protein staining was reduced in pterygia compared to conjunctiva.
- MSH2 protein staining was observed and appeared normal in pterygia.
- No reproducible microsatellite instability (MSI) or loss of heterozygosity (LOH) was detected in the examined pterygia.
Conclusions:
- The study did not confirm the presence of MSI or LOH in pterygia using the selected markers.
- MSH2 protein expression in pterygia was found to be normal.
- Reduced MLH1 protein levels were noted in pterygia, warranting further investigation.
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