Background - Since an increased number of epidermal growth factor receptors (EGFR) on tumor cell surfaces is common in squamous cell carcinomas (SCC), and since the majority (95%) of head and neck (H and N) malignancies are epidermoid in origin, we investigated the incidence of EGFR gene amplification in both H and N tumor cell lines and in primary human tumors. Methods - DNA was extracted from four well-characterized H and N tumor cell lines and from 30 fresh primary specimens, and studied for amplification of the EGFR gene using standard extraction, dot blot, autoradiography, and densitometry techniques. EGFR data from each patient was then compared with clinical factors, including clinical stage, histopathological differentiation, and number of positive lymph nodes. Results - Amplification (>2 fold increase in gene copy number) was seen in one of four (25%) cell lines and in three of thirty (10%) primary tumors. The EGFR amplification data failed to correlate significantly with any of the clinical parameters studied. Conclusion - Gene amplification does not appear to play a major causative role in the increased number of EGFRs commonly seen on the cell surface of H and N tumors, suggesting that the key step may lie 'downstream' in RNA overexpression or receptor protein overproduction.
|Original language||English (US)|
|Number of pages||7|
|State||Published - Dec 1 1991|
ASJC Scopus subject areas
- Cancer Research