Identification of differentially expressed genes in immortalized human bronchial epithelial cell line as a model for in vitro study of lung carcinogenesis

Abstract

Suppression subtractive hybridization (SSH) was applied to identify differentially expressed genes in the SV40LT immortalized human bronchial epithelial cell line Y‐BE, with normal human bronchial epithelial cells (HBEC) as a control. Two cDNA libraries of up‐ and downregulated genes were generated, comprising 218 known genes and 131 unknown genes in total. The expression of 22 clones from the 2 libraries was investigated by Northern blot analysis, and 86.4% (19/22) of them showed differential expression between Y‐BE cells and HBEC. Although the Y‐BE cells are nontumorigenic in nude mice, Comparative genomic hybridization (CGH) detected some DNA imbalances in Y‐BE cells that were similar to lung cancer cells. Our data demonstrate that the studied cell line Y‐BE and SSH is a reliable approach for identifying new genes that are associated with immortalization and early tumor development that may help to understand the pathogenesis of lung cancer.