BACKGROUND: Epidermal growth factor receptor (EGFR) overexpression is associated with poor prognosis in head and neck cancer. The first intron of EGFR gene is polymorphic (9-23 CA repeats) and transcription declines when the number of repeats increases. PATIENTS AND METHODS: EGFR polymorphism (fluorescent genotyping) and expression (ligand-binding assay) were analyzed in tumors and normal tissues from 112 patients (100 men, 12 women; mean age 60 years). RESULTS: The number of CA repeats varied from 15 to 22. Allelic distribution was trimodal (predominance of 16, 20 and 18 CA repeats). EGFR concentrations were significantly higher (P=0.02) in homozygous tumors as compared with heterozygous. Considering homozygous tumors, or classifying genotypes as short/long/intermediary (two alleles <17 versus two alleles > or =17 versus others), no relationship was observed between tumoral EGFR genotype and expression. In the 76 tumors exhibiting at least one 16-CA allele, the length of the remaining allele was inversely correlated to EGFR expression (P=0.047). Tumoral EGFR expression, performance status (WHO criteria) and node involvement were independent predictors of specific survival (P <0.01). Tumoral or normal tissue EGFR genotype did not influence survival. CONCLUSIONS: Intron 1 EGFR polymorphism may be implicated in the regulation of EGFR expression in head and neck tumors.
BACKGROUND:Epidermal growth factor receptor (EGFR) overexpression is associated with poor prognosis in head and neck cancer. The first intron of EGFR gene is polymorphic (9-23 CA repeats) and transcription declines when the number of repeats increases. PATIENTS AND METHODS: EGFR polymorphism (fluorescent genotyping) and expression (ligand-binding assay) were analyzed in tumors and normal tissues from 112 patients (100 men, 12 women; mean age 60 years). RESULTS: The number of CA repeats varied from 15 to 22. Allelic distribution was trimodal (predominance of 16, 20 and 18 CA repeats). EGFR concentrations were significantly higher (P=0.02) in homozygous tumors as compared with heterozygous. Considering homozygous tumors, or classifying genotypes as short/long/intermediary (two alleles <17 versus two alleles > or =17 versus others), no relationship was observed between tumoral EGFR genotype and expression. In the 76 tumors exhibiting at least one 16-CA allele, the length of the remaining allele was inversely correlated to EGFR expression (P=0.047). Tumoral EGFR expression, performance status (WHO criteria) and node involvement were independent predictors of specific survival (P <0.01). Tumoral or normal tissue EGFR genotype did not influence survival. CONCLUSIONS: Intron 1 EGFR polymorphism may be implicated in the regulation of EGFR expression in head and neck tumors.
Authors: Christian Freudlsperger; Jeffrey R Burnett; Jay A Friedman; Vishnu R Kannabiran; Zhong Chen; Carter Van Waes Journal: Expert Opin Ther Targets Date: 2010-11-26 Impact factor: 6.902
Authors: Andrey Frolov; J Spencer Liles; Andrew V Kossenkov; Ching-Wei D Tzeng; Nirag Jhala; Peter Kulesza; Shyam Varadarajulu; Mohamad Eloubeidi; Martin J Heslin; J Pablo Arnoletti Journal: Am J Surg Date: 2010-04-21 Impact factor: 2.565
Authors: G Milano; M-C Etienne-Grimaldi; L Dahan; M Francoual; J-P Spano; D Benchimol; M Chazal; C Letoublon; T André; F-N Gilly; J-R Delpero; J-L Formento Journal: Ann Oncol Date: 2008-07-15 Impact factor: 32.976
Authors: Juliette Thariat; Gokcen Yildirim; Kathryn A Mason; Adam S Garden; Luka Milas; K Kian Ang Journal: Int J Clin Oncol Date: 2007-04-27 Impact factor: 3.402