title: PIK3CA mutation in Chinese patients with lung squamous cell carcinoma.
abstract: OBJECTIVE
  To investigate PIK3CA mutation in Chinese patients with lung squamous cell carcinoma (LSCC) and explore their relationship with clinicopathological profiles.
  
  
  METHODS
  Tumor samples from 123 cases of LSCC were included in this study. PIK3CA mutations in exon 9 and 20 were screened by pyrosequencing and confirmed by clone sequencing or amplification refractory mutation system (ARMS). Denaturing performance liquid chromatography (DHPLC) was employed for evaluation of EGFR mutation in exon 19, 21 and KRAS mutation.
  
  
  RESULTS
  PIK3CA mutations were found in 3 (2.4%) patients. The mutation type included E545K, E452Q and H1047R. Of these three patients, one coupled with EGFR mutation, and the other two coupled with PIK3CA amplification. All the three patients shared the same clinicopathologic characteristics: male, less than 60 years old, had smoke history, stage III and carried wild-type KRAS.
  
  
  CONCLUSIONS
  The frequency of PIK3CA mutation is low in Chinese patients with LSCC. The mutational status of PIK3CA is not mutually exclusive to EGFR mutation.
authors.affiliation: Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Department of Thoracic Medical Oncology, Peking University Cancer Hospital & Institute, Beijing 100142, China.
authors.forename: Jinglin
authors.initials: J
authors.lastname: Yu
authors.forename: Hua
authors.initials: H
authors.lastname: Bai
authors.forename: Zhijie
authors.initials: Z
authors.lastname: Wang
authors.forename: Zhigang
authors.initials: Z
authors.lastname: Wei
authors.forename: Xiaosheng
authors.initials: X
authors.lastname: Ding
authors.forename: Jianchun
authors.initials: J
authors.lastname: Duan
authors.forename: Lu
authors.initials: L
authors.lastname: Yang
authors.forename: Meina
authors.initials: M
authors.lastname: Wu
authors.forename: Yuyan
authors.initials: Y
authors.lastname: Wang
authors.forename: Jie
authors.initials: J
authors.lastname: Wang
keywords: EGFR mutation; KRAS mutation; Lung squamous cell carcinoma (LSCC); PIK3CA mutation