Quantitative analysis of argyrophilic nucleolar organizer regions and epidermal growth factor receptor in ameloblastomas

Department of Oral Pathology, School of Dentistry, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
Journal of Oral Pathology and Medicine (Impact Factor: 1.93). 03/2007; 36(2):99-104. DOI: 10.1111/j.1600-0714.2007.00472.x
Source: PubMed


The aim of this study was to evaluate the proliferation activity by means of the quantification of the argyrophilic nucleolar organizer regions (AgNORs) and the patterns of expression of the epidermal growth factor receptor (EGFR) in ameloblastomas.
The methods of evaluation included the H/E stain for the morphologic analysis, the silver impregnation technique for quantification of the AgNORs and the immunohistochemical stain with anti-EGFR antibody in 11 cases of ameloblastoma.
The results did not show a significant statistical difference as per quantification of the AgNORs. The expression of the EGFR on the epithelial islands of ameloblastoma was not uniform, and the location of the expression was also variable. The predominant expression was that of cytoplasm and the islands with an expression of membrane only were rare and generally smaller in size.
The tumor presents an irregular growth. Smaller islands are associated with a higher proliferation activity and therefore could be responsible for tumor infiltration.

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Available from: Manoel Sant'Ana Filho, Dec 17, 2015
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    • "The mechanism of such local aggressiveness is still not known. For a better understanding of the aggressive behavior of ameloblastomas, investigations were carried out using biochemical and immunohistochemical methods to study the expression of metalloproteinases, growth factor receptors and their proliferative activity.[2] Among the various methods used for evaluation of proliferative activity, argyrophilic nucleolar organizer region (AgNOR) uses silver to stain the proteins associated with the active nucleolar organizer regions (NORs). "
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