title: Comparison of targeted next-generation sequencing with conventional sequencing for predicting the responsiveness to epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) therapy in never-smokers with lung adenocarcinoma.
abstract: OBJECTIVE
  To investigate the clinical utility of targeted next-generation sequencing (NGS) for predicting the responsiveness to epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) therapy, we compared the efficacy with conventional sequencing in never-smokers with lung adenocarcinoma (NSLAs).
  
  
  METHODS
  We obtained DNA from 48 NSLAs who received gefitinib or erlotinib for their recurrent disease after surgery. Sanger sequencing and peptide nucleic acid clamp polymerase chain reaction (PCR) were used to analyze EGFR, KRAS, BRAF, and PIK3CA mutations. We analyzed ALK, RET, and ROS1 rearrangements by fluorescent in situ hybridization or reverse transcriptase-PCR and quantitative real-time PCR. After molecular screening, Ion Torrent NGS was performed in 31 cases harboring only EGFR exon 19 deletions (19DEL), an L858R mutation, or none of the above mutations.
  
  
  RESULTS
  The 31 samples were divided into four groups: (1) responders to EGFR-TKIs with only 19DEL or L858R (n=15); (2) primary resistance to EGFR-TKI with only 19DEL or L858R (n=4); (3) primary resistance to EGFR-TKI without any mutations (n=8); (4) responders to EGFR-TKI without any mutations (n=4). With NGS, all conventionally detected mutations were confirmed except for one L858R in group 2. Additional uncovered predictive mutations with NGS included one PIK3CA E542K in group 2, two KRAS (G12V and G12D), one PIK3CA E542K, one concomitant PIK3CA and EGFR L858R in group 3, and one EGFR 19DEL in group 4.
  
  
  CONCLUSIONS
  Targeted NGS provided a more accurate and clinically useful molecular classification of NSLAs. It may improve the efficacy of EGFR-TKI therapy in lung cancer.
authors.affiliation: Lung Cancer Branch, Research Institute and Hospital, National Cancer Center, Goyang, Republic of Korea. Electronic address: jymama@ncc.re.kr.
authors.forename: Ji-Youn
authors.initials: JY
authors.lastname: Han
authors.affiliation: Lung Cancer Branch, Research Institute and Hospital, National Cancer Center, Goyang, Republic of Korea.
authors.forename: Sun Hye
authors.initials: SH
authors.lastname: Kim
authors.affiliation: Functional Genomic Branch, Research Institute and Hospital, National Cancer Center, Goyang, Republic of Korea.
authors.forename: Yeon-Su
authors.initials: YS
authors.lastname: Lee
authors.affiliation: TheregenEtex Bio Institute, Suwon, Republic of Korea.
authors.forename: Seung-Youn
authors.initials: SY
authors.lastname: Lee
authors.affiliation: Functional Genomic Branch, Research Institute and Hospital, National Cancer Center, Goyang, Republic of Korea.
authors.forename: Jung-Ah
authors.initials: JA
authors.lastname: Hwang
authors.affiliation: Lung Cancer Branch, Research Institute and Hospital, National Cancer Center, Goyang, Republic of Korea.
authors.forename: Jin Young
authors.initials: JY
authors.lastname: Kim
authors.affiliation: Lung Cancer Branch, Research Institute and Hospital, National Cancer Center, Goyang, Republic of Korea.
authors.forename: Sung Jin
authors.initials: SJ
authors.lastname: Yoon
authors.affiliation: Lung Cancer Branch, Research Institute and Hospital, National Cancer Center, Goyang, Republic of Korea.
authors.forename: Geon Kook
authors.initials: GK
authors.lastname: Lee
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis* / Q000188:drug therapy / Q000235:genetics* / Q000401:mortality; D000077192:Adenocarcinoma of Lung; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002289:Carcinoma, Non-Small-Cell Lung / Q000175:diagnosis / Q000188:drug therapy / Q000235:genetics / Q000401:mortality; D019295:Computational Biology; D004252:DNA Mutational Analysis; D066246:ErbB Receptors / Q000037:antagonists & inhibitors / Q000235:genetics*; D005260:Female; D011905:Genes, ras; D059014:High-Throughput Nucleotide Sequencing; D006801:Humans; D008175:Lung Neoplasms / Q000175:diagnosis* / Q000188:drug therapy / Q000235:genetics* / Q000401:mortality; D008297:Male; D008875:Middle Aged; D009154:Mutation; D009687:Nuclear Proteins / Q000235:genetics; D011379:Prognosis; D047428:Protein Kinase Inhibitors / Q000494:pharmacology / Q000627:therapeutic use; D048493:Proto-Oncogene Proteins B-raf / Q000235:genetics; D015203:Reproducibility of Results; D014157:Transcription Factors / Q000235:genetics; D016896:Treatment Outcome
chemical_list: D009687:Nuclear Proteins; C503859:PI3KCA protein, human; D047428:Protein Kinase Inhibitors; D014157:Transcription Factors; D066246:ErbB Receptors; D048493:Proto-Oncogene Proteins B-raf
keywords: EGFR; NGS; NSCLC; PIK3CA