AIM: To evaluate the importance of epidermal growth factor receptor (EGFR) protein overexpression and gene amplification in carcinogenesis of glottic cancer. METHOD: In order to evaluate EGFR expression at protein and gene level, immunohistochemical (IHC) analysis and fluorescent in situ hybridization (FISH) were performed on tissue microarrays of laryngeal tissue (145 samples) -- 38 samples of normal mucosa, 46 samples of hyperplastic lesions, and 61 samples of cancerous lesions. RESULTS: Membranous (mEGFR) and cytoplasmic (cEGFR) EGFR expression was significantly different between the analyzed groups. The differences were most striking in the suprabasal-transforming zone. IHC evaluation showed that high and low mEGFR staining contributed to the differentiation of dysplastic lesions, simple hyperplasia, and cancerous tissue, as well as between different degrees of atypia in hyperplastic lesions (P<0.050). EGFR gene amplification was not found in simple and abnormal hyperplastic lesions, but it was confirmed in 2/21 atypical hyperplasias, indicating that gene amplification can facilitate identification of malignant potential in hyperplastic lesions. In cancerous tissue, EGFR gene amplification was found in 8/50 samples. EGFR gene amplification was found in preinvasive cancer in one patient. In invasive carcinomas, gene amplification was not associated with stage or grade. Carcinomas with gene amplification showed significantly higher cEGFR expression (basal layer P=0.003; suprabasal layer P=0.002). CONCLUSIONS: This study confirmed an increase in EGFR protein expression and gene amplification with the increase in biological aggressiveness of glottic lesions. A correlation between EGFR gene amplification and protein expression was established. Gene amplification proved to be an early event in glottic carcinogenesis, indicating its importance for glottic cancer prevention, early detection, and protocol selection.
AIM: To evaluate the importance of epidermal growth factor receptor (EGFR) protein overexpression and gene amplification in carcinogenesis of glottic cancer. METHOD: In order to evaluate EGFR expression at protein and gene level, immunohistochemical (IHC) analysis and fluorescent in situ hybridization (FISH) were performed on tissue microarrays of laryngeal tissue (145 samples) -- 38 samples of normal mucosa, 46 samples of hyperplastic lesions, and 61 samples of cancerous lesions. RESULTS: Membranous (mEGFR) and cytoplasmic (cEGFR) EGFR expression was significantly different between the analyzed groups. The differences were most striking in the suprabasal-transforming zone. IHC evaluation showed that high and low mEGFR staining contributed to the differentiation of dysplastic lesions, simple hyperplasia, and cancerous tissue, as well as between different degrees of atypia in hyperplastic lesions (P<0.050). EGFR gene amplification was not found in simple and abnormal hyperplastic lesions, but it was confirmed in 2/21 atypical hyperplasias, indicating that gene amplification can facilitate identification of malignant potential in hyperplastic lesions. In cancerous tissue, EGFR gene amplification was found in 8/50 samples. EGFR gene amplification was found in preinvasive cancer in one patient. In invasive carcinomas, gene amplification was not associated with stage or grade. Carcinomas with gene amplification showed significantly higher cEGFR expression (basal layer P=0.003; suprabasal layer P=0.002). CONCLUSIONS: This study confirmed an increase in EGFR protein expression and gene amplification with the increase in biological aggressiveness of glottic lesions. A correlation between EGFR gene amplification and protein expression was established. Gene amplification proved to be an early event in glottic carcinogenesis, indicating its importance for glottic cancer prevention, early detection, and protocol selection.
Authors: Larry E Morrison; Kristine K Jacobson; Michael Friedman; James W Schroeder; John S Coon Journal: Laryngoscope Date: 2005-07 Impact factor: 3.325
Authors: Fred R Hirsch; Marileila Varella-Garcia; Jason McCoy; Howard West; Ana Carolina Xavier; Paul Gumerlock; Paul A Bunn; Wilbur A Franklin; John Crowley; David R Gandara Journal: J Clin Oncol Date: 2005-07-05 Impact factor: 44.544
Authors: Jong Woo Lee; Young Hwa Soung; Su Young Kim; Hyo Kyung Nam; Won Sang Park; Suk Woo Nam; Min Sik Kim; Dong Il Sun; Youn Soo Lee; Ja June Jang; Jung Young Lee; Nam Jin Yoo; Sug Hyung Lee Journal: Clin Cancer Res Date: 2005-04-15 Impact factor: 12.531