IV. To evaluate the effect on endobronchial brushing and biopsy gene expression of peroxisome proliferator-activated receptor gamma (PPARgamma), glutathione S-transferase mu (GSTmu), carboxylesterase 1 (Ces1), Fos-related antigen 1 (FosL1), cytochrome p4502e1, stearoyl coA desaturase 1, tumor necrosis factor (TNF) superfamily member 9, transforming growth factor beta (TGFbeta), Jun and a 46 gene panel associated with dysplasia persistence, using Affymetrix arrays.