title: Study of differential proteins in lung adenocarcinoma using laser capture microdissection combined with liquid chip-mass spectrometry technology.
abstract: BACKGROUND
  In recent years the proportion of lung adenocarcinoma (adCA) which occurs in lung cancer patients has increased. Using laser capture microdissection (LCM) combined with liquid chip-mass spectrometry technology, we aimed to screen lung cancer biomarkers by studying the proteins in the tissues of adCA.
  
  
  METHODS
  We used LCM and magnetic bead based weak cation exchange (MB-WCX) to separate and purify the homogeneous adCA cells and normal cells from six cases of fresh adCA and matched normal lung tissues. The proteins were analyzed and identified by matrix assisted laser desorption/ionization time-of-fight mass spectrometry (MALDI-OF-MS). We screened for the best pattern using a radial basic function neural network algorithm.
  
  
  RESULTS
  About 2.895 × 10(6) and 1.584 × 10(6) cells were satisfactorily obtained by LCM from six cases of fresh lung adCA and matched normal lung tissues, respectively. The homogeneities of cell population were estimated to be over 95% as determined by microscopic visualization. Comparing the differentially expressed proteins between the lung adCA and the matched normal lung group, 221 and 239 protein peaks, respectively, were found in the mass-to-charge ration (M/Z) between 800 Da and 10 000 Da. According to t test, the expression of two protein peaks at 7521.5 M/Z and 5079.3 M/Z had the largest difference between tissues. They were more weakly expressed in the lung adCA compared to the matched normal group. The two protein peaks could accurately separate the lung adCA from the matched normal lung group by the sample distribution chart. A discriminatory pattern which can separate the lung adCA from the matched normal lung tissue consisting of three proteins at 3358.1 M/Z, 5079.3 M/Z and 7521.5 M/Z was established by a radial basic function neural network algorithm with a sensitivity of 100% and a specificity of 100%.
  
  
  CONCLUSIONS
  Differential proteins in lung adCA were screened using LCM combined with liquid chip-mass spectrometry technology, and a biomarker model was established. It is possible that this technology is going to become a powerful tool in screening and early diagnosis of lung adCA.
authors.affiliation: Department of Respiratory Medicine, Second Affiliated Hospital of Medical School, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, China.
authors.forename: Li-Na
authors.initials: LN
authors.lastname: Bu
authors.forename: Shuan-Ying
authors.initials: SY
authors.lastname: Yang
authors.forename: Feng-Tao
authors.initials: FT
authors.lastname: Li
authors.forename: Wen-Li
authors.initials: WL
authors.lastname: Shang
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.forename: Shu-Fen
authors.initials: SF
authors.lastname: Huo
authors.forename: Yan-Dong
authors.initials: YD
authors.lastname: Nan
authors.forename: Ying-Xuan
authors.initials: YX
authors.lastname: Tian
authors.forename: Jie
authors.initials: J
authors.lastname: DU
authors.forename: Xiu-Li
authors.initials: XL
authors.lastname: Lin
authors.forename: Yan-Feng
authors.initials: YF
authors.lastname: Liu
authors.forename: Yu-Rong
authors.initials: YR
authors.lastname: Lin
authors.forename: Biao-Xue
authors.initials: BX
authors.lastname: Rong
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism; D000077192:Adenocarcinoma of Lung; D000368:Aged; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D008175:Lung Neoplasms / Q000378:metabolism*; D008297:Male; D042282:Microdissection / Q000379:methods*; D008875:Middle Aged; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*