Immunohistochemical expression of EGFR in oral leukoplakia: association with clinicopathological features and cellular proliferation.
OBJECTIVE
To investigate the immunoexpression of epidermal growth factor receptor (EGFR) in a sample of oral leukoplakias (OL) and to determine the receptor' s association with dysplasia, tobacco consumption, lesion site, and proliferation rate. Although EGFR should be overexpressed in some oral leukoplakias, the factors that may interfere with this expression and the influence of this receptor on epithelial proliferation have yet to be investigated.


METHODS
Samples of oral leukoplakias (48) and of normal oral epithelium (10) were immunohistologically examined for expression of EGFR. Immunohistochemistry for Ki-67, and p27 were also performed in leukoplakias. EGFR expression was associated with clinical and pathological features.


RESULTS
EGFR was positive in 62.5% of the leukoplakias and 50% of normal oral epithelium. The number of EGFR positive OL located in high-risk sites was significantly higher than EGFR positive OL located in low-risk sites. Most of the p27 negative leukoplakias were EGFR positive, and the p27 index in the parabasal layer was diminished in the presence of dysplasia. Positivity for EGFR was not associated with dysplasia, tobacco exposure, or Ki-67.


CONCLUSIONS
EGFR is expressed in leukoplakia regardless of dysplasia, but EGFR positivity should be more frequent in lesions sited in areas of high cancer risk. The association between EGFR and p27 may represent an important mechanism in the control of cellular proliferation and malignant progression of oral epithelium and therefore warrants further investigation.
Department of Oral Pathology and Surgery, School of Dentistry, Universidade Federal de Minas Gerais, Faculdade de Odontologia, Av. Antônio Carlos, 6627 sala 3201, Pampulha 31.270-901, Belo Horizonte, MG, Brazil.
Daniela-Cotta
DC
Ribeiro
Frederico-Omar
FO
Gleber-Netto
Sílvia-Ferreira
SF
Sousa
Vanessa-de-Fátima
VD
Bernardes
Mauro-Henrique-Nogueira
MH
Guimarães-Abreu
Maria-Cássia-Ferreira
MC
Aguiar
D000328:Adult; D000368:Aged; D049109:Cell Proliferation; D066246:ErbB Receptors / Q000096:biosynthesis*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007972:Leukoplakia, Oral / Q000378:metabolism* / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D055815:Young Adult
D066246:ErbB Receptors