Interphase Cytogenetics of Lung Tumors Using In Situ Hybridization: Numerical Aberrations

Abstract

ObjectivesSince conventional cytogenetic analysis for bronchogenic carcinogenesis is limited by the difficulty to get enough number of high quality metaphase spreads, the development of new method to overcome above problems is strongly needed. Therefore, the introduction of non-radioactive in situ hybridization (ISH) with pericentromeric chromosome probes gave us the way to investigate the genetic events during carcinogenic process. We applied this method on lung cancer tissue to validate the possibility of this method for general usage and to analyze numerical chromosome aberration status and their clinical correlations.MethodsA set of satellite DNA probes specific for chromosome 3, 7, 9, 11, and 17 was hybridized directly to paraffin-embedded tissue section of 30 non-small cell lung cancers. Mean chromosome index of each chromosome and frequency of polysomy for each chromosome were calculated.ResultsMean chromosome indices for chromosome 3, 7, 9, 11, and 17 were 1.10, 1.13, 1.17, 1.12, and 1.17. respectively. Polysomy for a set of chromosomes was detected in all 30 cases except 4 cases which showed hypoploidy only for chromosome 3 or 7 in 2 cases and diploidy only for chromosome 3 or 11 in 2 cases. Among the set of chromosomes, mean chromosome index and polysomy frequency for chromosome 9 & 17 were significantly higher than that for others. Mean chromosome index or polysomy pattern for each chromosome was not much different among cell types or clinical stages.ConclusionsOur results show that chromosome ISH can be used to screen for numerical chromosome aberrations on paraffin tissue sections and further studies for ISH analysis with different probes on same tumor area or double-target ISH in large scale are needed to confirm above results and to elucidate the specific meanings.

A fluorescence in situ hybridization-based assay for improved detection of lung cancer cells in bronchial washing specimens

“…CGH and FISH studies of resected lung carcinoma tissue have shown that non–small cell and small cell lung carcinoma are characterized by widespread gains (low‐level and high‐level) and losses of genetic material at various chromosomal loci 20, 21, 27, 41–45. This has led a few investigators to use FISH to assess sputum or bronchoscopically obtained specimens for evidence of lung carcinoma cells 6, 37, 46, 47…”