title: EGFR mRNA is upregulated, but somatic mutations of the gene are hardly found in renal cell carcinoma in Japanese patients.
abstract: OBJECTIVE
  Heterozygous somatic mutations of epidermal growth factor receptor (EGFR) in exons 18, 19, and 21 were recently reported to be associated with response to gefitinib in patients having nonsmall cell lung cancer. Such mutations are more frequently found among Japanese than Europeans. In this work, the frequency of mutations was investigated in renal cell carcinoma (RCC) samples obtained from Japanese subjects to examine the potential of gefitinib as a therapeutic agent for RCC.
  
  
  METHODS
  Nineteen patients with RCC, who gave written informed consent, were enrolled in this study. mRNA expression levels of EGFR were measured in RCC and its adjacent noncancerous renal tissue via the real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR) method. Somatic mutations were determined using genomic DNA extracted from RCC by direct sequencing method.
  
  
  RESULTS
  mRNA expression was confirmed to be about 19 times higher in RCC than in adjacent noncancerous renal tissues, but no such mutations were detected in both.
  
  
  CONCLUSIONS
  Results from this study do not support the validity of further clinical trials on gefitinib for RCC with genotyping even in Japanese patients, although EGFR plays a key role in tumor progression.
authors.affiliation: Department of Hospital Pharmacy, School of Medicine, Kobe University, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan.
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Sakaeda
authors.forename: Noboru
authors.initials: N
authors.lastname: Okamura
authors.forename: Akinobu
authors.initials: A
authors.lastname: Gotoh
authors.forename: Toshiro
authors.initials: T
authors.lastname: Shirakawa
authors.forename: Shuji
authors.initials: S
authors.lastname: Terao
authors.forename: Masahi
authors.initials: M
authors.lastname: Morioka
authors.forename: Kenji
authors.initials: K
authors.lastname: Tokui
authors.forename: Hisato
authors.initials: H
authors.lastname: Tanaka
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Nakamura
authors.forename: Mariko
authors.initials: M
authors.lastname: Yagi
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Nishimura
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Yokoyama
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Okumura
mesh_terms: D002292:Carcinoma, Renal Cell / Q000235:genetics* / Q000378:metabolism; D066246:ErbB Receptors / Q000096:biosynthesis / Q000235:genetics*; D005260:Female; D006801:Humans; D007564:Japan; D007680:Kidney Neoplasms / Q000235:genetics* / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009154:Mutation; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism*; D015854:Up-Regulation
chemical_list: D012333:RNA, Messenger; D066246:ErbB Receptors