title: Isolation and characterization of erlotinib-resistant human non-small cell lung cancer A549 cells.
abstract: Erlotinib, an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, is an effective therapy for non-small cell lung cancer (NSCLC). However, resistance to erlotinib reduces its efficacy. To investigate the basis of erlotinib resistance, we isolated erlotinib-resistant human NSCLC A549 cells, termed A549/ER cells. The A549/ER cells were found to be resistant to erlotinib, as well as paclitaxel and gemcitabine. We then performed a PCR array to investigate the resistance to erlotinib in A549/ER cells. EGFR expression in A549/ER cells was decreased compared to A549 cells. The expression of fibroblast growth factor 2 (FGF2) and p21 in A549/ER was increased when compared to A549 cells. Our results suggest that the down-regulation of EGFR and up-regulation of FGF2 is related to resistance to erlotinib in A549/ER cells.
authors.affiliation: Department of Clinical Pharmacy and Pharmacology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima, Japan.
authors.forename: Ryuji
authors.initials: R
authors.lastname: Ikeda
authors.forename: Lee C
authors.initials: LC
authors.lastname: Vermeulen
authors.forename: Elim
authors.initials: E
authors.lastname: Lau
authors.forename: Zhisheng
authors.initials: Z
authors.lastname: Jiang
authors.forename: Shannon M
authors.initials: SM
authors.lastname: Kavanaugh
authors.forename: Katsushi
authors.initials: K
authors.lastname: Yamada
authors.forename: Jill M
authors.initials: JM
authors.lastname: Kolesar