title: Relationship between epidermal growth factor receptor gene mutation and copy number in Chinese patients with non-small cell lung cancer.
abstract: Epidermal growth factor receptor (EGFR) gene mutation and copy number are useful predictive markers that guide the selection of non-small cell lung cancer (NSCLC) patients for EGFR-targeting therapy. This study aimed to investigate the correlation between EGFR gene mutation and copy number and clinicopathologic characteristics of Chinese patients with NSCLC. NSCLC specimens collected from 205 patients between November 2009 and January 2011 were selected to detect EGFR gene mutations with real-time polymerase chain reaction (RT-PCR) and to detect EGFR gene copy number with fluorescence in situ hybridization (FISH). EGFR mutations primarily occurred in females, non-smokers, and patients with adenocarinomas (all P < 0.001). Tissues from 128 (62%) patients were FISH-positive for EGFR, including 37 (18%) with gene amplification and 91 (44%) with high polysomy. EGFR gene mutation was correlated with FISH-positive status (R = 0.340, P < 0.001). Multivariate analysis showed that not smoking (OR = 5.910, 95% CI = 2.363-14.779, P < 0.001) and having adenocarcinoma (OR = 0.122, 95% CI = 0.026-0.581, P = 0.008) were favorable factors for EGFR gene mutation. These results show a high frequency of EGFR FISH positivity in NSCLC tissues from Chinese patients and a significant relevance between EGFR gene mutations and FISH-positive status. Among the FISH-positive samples, EGFR gene mutation occurred more frequently in samples with gene amplification compared to those with high polysomy, suggesting that EGFR mutation and gene amplification should be used as clinical decision parameters to predict response to EGFR-targeting therapy.
authors.affiliation: Department of Thoracic Surgery, Sun Yat-sen University Cancer Center, Guangdong, People's Republic of China. zhlanj@mail.sysu.edu.cn
authors.forename: Lan-Jun
authors.initials: LJ
authors.lastname: Zhang
authors.forename: Ling
authors.initials: L
authors.lastname: Cai
authors.forename: Zhe
authors.initials: Z
authors.lastname: Li
authors.forename: Wu-Ping
authors.initials: WP
authors.lastname: Wang
authors.forename: Kang
authors.initials: K
authors.lastname: Guo
authors.forename: Jian-Yong
authors.initials: JY
authors.lastname: Shao
authors.forename: Jun-Ye
authors.initials: JY
authors.lastname: Wang
authors.forename: Hui
authors.initials: H
authors.lastname: Yu
authors.forename: Tie-Hua
authors.initials: TH
authors.lastname: Rong
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics / Q000378:metabolism; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D044466:Asian People / Q000235:genetics; D002289:Carcinoma, Non-Small-Cell Lung / Q000235:genetics* / Q000378:metabolism; D066246:ErbB Receptors / Q000235:genetics* / Q000378:metabolism; D005260:Female; D005784:Gene Amplification; D018628:Gene Dosage; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008175:Lung Neoplasms / Q000235:genetics* / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009154:Mutation; D060888:Real-Time Polymerase Chain Reaction; D012907:Smoking
chemical_list: C512478:EGFR protein, human; D066246:ErbB Receptors