COMPARATIVE GENOMIC HYBRIDIZATION ANALYSIS DETECTS FREQUENT, OFTEN HIGH-LEVEL, OVERREPRESENTATION OF DNA-SEQUENCES AT 3Q, 5P, 7P, AND 8Q INHUMAN NONSMALL CELL LUNG CARCINOMAS

Comparative genomic hybridization analysis was used to identify chromo somal imbalances in 20 non-small cell lung carcinoma (NSCLC) biopsies and cell lines. The chromosome arms most often overrepresented were 3q (85%), 5p (70%), 7p, (65%), and 8q (65%), which were observed at high copy numbers in many cases. Other common overrepresented sites were I q, 2p, and 20p. DNA sequence amplification was often observed, with th e most frequent site being 3q26 (six cases). Other recurrent sites of amplification included 8q24, 3q13, 3q28-qter, 7q11.2, 8p11-12, 12p12, and 19q13.1-13.2. The most frequent underrepresented segment was 3p21 (50%); other recurrent sites of autosomal loss included 8p21-pter, 15q 11.2-13, 5q11.2-15, 9p, 13q12-14, 17p, and 18q21-qter. These regions o f copy number decreases are also common sites of allelic loss, further implicating these sites as locations of tumor suppressor genes. Altho ugh some of the overrepresented segments harbor known or suspected onc ogenes/growth-regulatory genes, we have identified 3q and 5p as new si tes that are very frequently overrepresented in NSCLC. These findings could represent entry points for the identification of novel amplified DNA sequences that may contribute to the development or progression o f NSCLC.