Competitive PCR to detect eIF4E gene amplification in head and neck cancer

Background The protein eukaryotic initiation factor 4E (eIF4E) binds to messenger ribonucleic acid (mRNA) as the initial step in protein synthesis. Overexpression of eIF4E results in upregulation of specific proteins essential to cell growth and division. Overexpression of eIF4E has been found in head and neck squamous cell carcinoma (HNSCC) and breast carcinoma. This study's purpose is to determine whether eIF4E overexpression is present and associated with eIF4E gene amplification in HNSCC. Methods Competitive polymerase chain reaction (PCR) was performed on eight HNSCC and seven intraoral benign lesions to determine the copy number of eIF4E relative to a reference gene, gastrin. Western blots were performed to quantify eIF4E protein expression. Results All eight HNSCC specimens demonstrated significant (p < .005) overexpression of eIF4E protein (14.1 ± 10.4) and eIF4E gene amplification (4.5 ± 1.2). Benign tissue did not exhibit eIF4E protein overexpression or gene amplification. Conclusions Overexpression and associated gene amplification of eIF4E were present in HNSCC but not in benign tissue. Gene amplification of eIF4E may be an important mechanism for eIF4E overexpression. © 1999 John Wiley & Sons, Inc. Head Neck 21: 60–65, 1999.