Abstract
BACKGROUND.
It is believed that epithelial‐mesenchymal transition (EMT) occurs during the development and progression of cancer; however, the correlation between tobacco smoking and EMT remains to be elucidated.
METHODS.
Cells from the bronchioloalveolar carcinoma cell line A549 were exposed to benzo(a)pyrene (B[a]P) for 24 weeks, and morphology, proliferative activity, and gene expression profiles were analyzed.
RESULTS.
Although no apparent morphologic changes were observed, the B[a]P‐exposed A549 cells exhibited enhanced proliferative activity in 1% bovine serum that contained medium, and dramatic changes in expression levels were observed in a large number of genes. Of those, the expression of EMT‐related genes, such as migration‐stimulating factor, plasminogen activator inhibitor‐1, fibronectin, twist, transforming growth factor‐β2, basic fibroblast growth factor, and electron transport system, were up‐regulated; whereas gene expression of E‐cadherin was decreased. Most enhanced expression levels remained 8 weeks after the retrieval of B[a]P in culture.
CONCLUSIONS.
The current results indicated that B[a]P seems to induce EMT in lung cancer cells, and it also may drive disease progression in patients with lung cancer. Cancer 2007. © 2007 American Cancer Society.