Comparative genomic hybridization array analysis and real-time PCR reveals genomic copy number alteration for lung adenocarcinomas

Genomic alterations in lung cancer tissues have been observed in various studies. To analyze the aberrations in the genome of lung cancer patients, we used array comparative genomic hybridization (array CGH) in 15 lung adenocarcinoma (AdC) tissues. Copy number gains and losses in chromosomal regions were detected and corresponding genes were confirmed by real-time polymerase chain reaction (PCR). As for the results, several frequently altered loci, including gain of 16p (46% of samples), were found, and the most common losses were found in 14q32.33 (26% of samples). High-level DNA amplifications (> 0.8 log₂ ratio) were detected at 1p, 5p, 7p, 9p, 11p, 11q, 12q, 14q, 16p, 17q, 19q, 20p, 21q, and 22q. A subset of genes, gained or lost, was checked for over- or underrepresentation by means of real-time PCR. The degree of fold change was highest in ECGF1 (22q13.33), HOXA9 (7p15.2), MAFG (17q25.3), TSC2 (16p13.3), and ICAM1 (19p13.2) genes and the 16p chromosome terminal region (16p13.3pter). Taken together, these results show that array CGH could be used as a powerful tool for identification of genomic alteration for lung cancer, and the above-mentioned genes may represent potential candidate genes in the study of lung cancer pathogenesis and diagnosis.