title: C-kit gene mutation in human gastrointestinal stromal tumors.
abstract: OBJECTIVE
  To investigate the significance of c-kit gene mutation in gastrointestinal stromal tumors (GIST).
  
  
  METHODS
  Fifty two cases of GIST and 28 cases of other tumors were examined. DNA samples were extracted from paraffin sections and fresh blocks. Exons 11, 9 and 13 of the c-kit gene were amplified by PCR and sequenced.
  
  
  RESULTS
  Mutations of exon 11 were found in 14 of 25 malignant GISTs (56%), mutations of exon 11 of the c-kit gene were revealed in 2 of 19 borderline GISTs (10.5%), and no mutation was found in benign tumors. The mutation rate showed significant difference (chi2=14.39, P<0.01) between malignant and benign GISTs. Most of mutations consisted of the in-frame deletion or replication from 3 to 48 bp in heterozygous and homozygous fashions, None of the mutations disrupted the downstream reading frame of the gene. Point mutations and frame deletions were most frequently observed at codons 550-560, but duplications were most concentrated at codons 570-585. No mutations of exons 9 and 13 were revealed in GISTs, Neither c-kit gene expression nor gene mutations were found in 3 leiomyomas, 8 leiomyosarcomas, 2 schwannomas, 2 malignant peripheral nerve sheath tumors, 2 intra-abdominal fibromatoses, 2 malignant fibrous histiocytomas and 9 adenocarcinomas.
  
  
  CONCLUSIONS
  C-kit gene mutations occur preferentially in malignant GISTs and might be a clinically useful adjunct marker in the evaluation of GISTs and can help to differentiate GISTs from other mesenchymal tumors of gastrointestinal tract, such as smooth muscle tumors, schwannomas, etc.
authors.affiliation: Department of Pathology, Zongshan Hospital, Fudan University, Shanghai 200032, China.
authors.forename: Ying-Yong
authors.initials: YY
authors.lastname: Hou
authors.forename: Yun-Shan
authors.initials: YS
authors.lastname: Tan
authors.forename: Meng-Hong
authors.initials: MH
authors.lastname: Sun
authors.forename: Yong-Kun
authors.initials: YK
authors.lastname: Wei
authors.forename: Jian-Fang
authors.initials: JF
authors.lastname: Xu
authors.forename: Shao-Hua
authors.initials: SH
authors.lastname: Lu
authors.forename: Su-Jie
authors.initials: SJ
authors.lastname: A-Ke-Su
authors.forename: Yan-Nan
authors.initials: YN
authors.lastname: Zhou
authors.forename: Feng
authors.initials: F
authors.lastname: Gao
authors.forename: Ai-Hua
authors.initials: AH
authors.lastname: Zheng
authors.forename: Tai-Ming
authors.initials: TM
authors.lastname: Zhang
authors.forename: Wen-Zhong
authors.initials: WZ
authors.lastname: Hou
authors.forename: Jian
authors.initials: J
authors.lastname: Wang
authors.forename: Xiang
authors.initials: X
authors.lastname: Du
authors.forename: Xiong-Zeng
authors.initials: XZ
authors.lastname: Zhu
mesh_terms: D000595:Amino Acid Sequence; D004252:DNA Mutational Analysis; D005091:Exons; D005770:Gastrointestinal Neoplasms / Q000235:genetics*; D006801:Humans; D008969:Molecular Sequence Data; D009154:Mutation; D019009:Proto-Oncogene Proteins c-kit / Q000235:genetics* / Q000378:metabolism; D017154:Stromal Cells / Q000502:physiology*
chemical_list: D019009:Proto-Oncogene Proteins c-kit