AMPLIFICATION AND OVEREXPRESSION OF THE EPIDERMAL GROWTH-FACTOR RECEPTOR GENE IN HUMAN RENAL-CELL CARCINOMA

We examined 22 cases of renal‐cell carcinoma (RCC) for structural alterations of the epidermal growth factor receptor (EGFR) gene and found gene amplification in one case of high‐stage‐high‐grade RCC. Dot blot analysis of the total RNA from tumorous and normal kidney tissues revealed overexpression of the EGFR gene in 12 of 20 (60%) cases of RCC. The highest expression was observed in the geneamplified case. No correlation was observed between the level of EGFR mRNA and tumor stage or grade. Northern blot analysis revealed normal 10‐ and 5.6‐kb EGFR mRNA bands in RCC. Our data indicate that gene amplification of the EGFR gene is one of the molecular mechanisms of its overexpression in a subset of RCCs. Copyright © 1990 Wiley‐Liss, Inc., A Wiley Company