title: High frequency of epidermal growth factor receptor mutations with complex patterns in non-small cell lung cancers related to gefitinib responsiveness in Taiwan.
abstract: OBJECTIVE
  Epidermal growth factor receptor (EGFR) mutations related to gefitinib responsiveness in non-small cell lung cancer have been found recently. Detection of EGFR mutations has become an important issue for therapeutic decision-making in non-small cell lung cancer.
  
  
  METHODS
  Mutational analysis of the kinase domain of EGFR coding sequence was done on 101 fresh frozen tumor tissues from patients without prior gefitinib treatment and 16 paraffin-embedded tumor tissues from patients treated with gefitinib. Detection of phosphorylated EGFR by immunoblot was also done on frozen tumor tissues.
  
  
  RESULTS
  The 101 non-small cell lung cancer tumor specimens include 69 adenocarcinomas, 24 squamous cell carcinomas, and 8 other types of non-small cell lung cancers. Mutation(s) in the kinase domain (exon 18 to exon 21) of the EGFR gene were identified in 39 patients. All of the mutations occurred in adenocarcinoma, except one that was in an adenosquamous carcinoma. The mutation rate in adenocarcinoma was 55% (38 of 69). For the 16 patients treated with gefitinib, 7 of the 9 responders had EGFR mutations, and only 1 of the 7 nonresponders had mutations, which included a nonsense mutation. The mutations seem to be complex in that altogether 23 different mutations were observed, and 9 tumors carried 2 mutations.
  
  
  CONCLUSIONS
  Data from our study would predict a higher gefitinib response rate in lung adenocarcinoma patients in Chinese and, possibly, other East Asian populations. The tight association with adenocarcinoma and the high frequency of mutations raise the possibility that EGFR mutations play an important role in the tumorigenesis of adenocarcinoma of lung, especially in East Asians.
authors.affiliation: Division of Molecular and Genomic Medicine, National Health Research Institutes, Taipei, Taiwan.
authors.forename: Shiu-Feng
authors.initials: SF
authors.lastname: Huang
authors.forename: Hui-Ping
authors.initials: HP
authors.lastname: Liu
authors.forename: Ling-Hui
authors.initials: LH
authors.lastname: Li
authors.forename: Yuan-Chieh
authors.initials: YC
authors.lastname: Ku
authors.forename: Yu-Ning
authors.initials: YN
authors.lastname: Fu
authors.forename: Hsien-Yu
authors.initials: HY
authors.lastname: Tsai
authors.forename: Ya-Ting
authors.initials: YT
authors.lastname: Chen
authors.forename: Yung-Feng
authors.initials: YF
authors.lastname: Lin
authors.forename: Wen-Cheng
authors.initials: WC
authors.lastname: Chang
authors.forename: Han-Pin
authors.initials: HP
authors.lastname: Kuo
authors.forename: Yi-Cheng
authors.initials: YC
authors.lastname: Wu
authors.forename: Yi-Rong
authors.initials: YR
authors.lastname: Chen
authors.forename: Shih-Feng
authors.initials: SF
authors.lastname: Tsai
mesh_terms: D000230:Adenocarcinoma / Q000188:drug therapy / Q000453:epidemiology / Q000235:genetics; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000595:Amino Acid Sequence; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D001483:Base Sequence; D018196:Carcinoma, Adenosquamous / Q000188:drug therapy / Q000453:epidemiology / Q000235:genetics; D002289:Carcinoma, Non-Small-Cell Lung / Q000188:drug therapy / Q000453:epidemiology / Q000235:genetics*; D002294:Carcinoma, Squamous Cell / Q000188:drug therapy / Q000453:epidemiology / Q000235:genetics; D066246:ErbB Receptors / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D005260:Female; D000077156:Gefitinib; D006801:Humans; D015151:Immunoblotting; D008175:Lung Neoplasms / Q000188:drug therapy / Q000453:epidemiology / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D020125:Mutation, Missense / Q000235:genetics*; D010766:Phosphorylation / Q000187:drug effects; D011799:Quinazolines / Q000627:therapeutic use*; D012689:Sequence Homology, Nucleic Acid; D013624:Taiwan / Q000453:epidemiology
chemical_list: D000970:Antineoplastic Agents; D011799:Quinazolines; D066246:ErbB Receptors; D000077156:Gefitinib