title: Proteomic Profiling of Invasive Ductal Carcinoma (IDC) using Magnetic Beads-based Serum Fractionation and MALDI-TOF MS.
abstract: OBJECTIVE
  To reveal the serum proteomic profiling of intraductal carcinoma (IDC) patients in China, establish a serum proteome fractionation technique for choosing magnetic beads for proteomic analysis in breast cancer research; and identify differentially expressed peptides (m/z; P < 0.0001) as potential biomarkers of early IDCs.
  
  
  METHODS
  We used two different kinds of magnetic beads (magnetic bead-based weak cation exchange chromatography (MB-WCX) and immobilized metal ion affinity chromatography (MB-IMAC-Cu)) to analyze 32 patients with early stage (stages I-II) IDC and 32 healthy control serum samples for proteomic profiling by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis. The mass spectra, analyzed using ClinProTools software, distinguished between IDC patients and healthy individuals based on k-nearest neighbor genetic algorithm.
  
  
  RESULTS
  The serum samples purified in the MB-WCX group provided better proteomic patterns than the MB-IMAC-Cu group. The samples purified by MB-WCX had better average peak numbers, higher peak intensities, and better capturing ability of low abundance proteins or peptides in serum samples. In addition, the MB-WCX and MB-IMAC-Cu purification methods, followed MALDI-TOF MS identification and use of ClinProTools software accurately distinguished patients with early stage IDC from healthy individuals.
  
  
  CONCLUSIONS
  Serum proteomic profiling by MALDI-TOF MS is a novel potential tool for the clinical diagnosis of patients with IDC in China.
authors.affiliation: Department of Genetics and Molecular Biology, Medical School of Xi'an Jiaotong University / Key Laboratory of Environment and Disease-Related Gene, Ministry of Education, Xi'an, China.
authors.forename: Juan
authors.initials: J
authors.lastname: Yang
authors.affiliation: Department of Mastopathy, Shaanxi Provincial Tumor Hospital, Xi'an, China.
authors.forename: Jiang
authors.initials: J
authors.lastname: Zhu
authors.affiliation: Department of Genetics and Molecular Biology, Medical School of Xi'an Jiaotong University / Key Laboratory of Environment and Disease-Related Gene, Ministry of Education, Xi'an, China.
authors.forename: Kang
authors.initials: K
authors.lastname: He
authors.affiliation: Department of Genetics and Molecular Biology, Medical School of Xi'an Jiaotong University / Key Laboratory of Environment and Disease-Related Gene, Ministry of Education, Xi'an, China.
authors.forename: Ling-Yu
authors.initials: LY
authors.lastname: Zhao
authors.affiliation: Department of Genetics and Molecular Biology, Medical School of Xi'an Jiaotong University / Key Laboratory of Environment and Disease-Related Gene, Ministry of Education, Xi'an, China.
authors.forename: Li-Ying
authors.initials: LY
authors.lastname: Liu
authors.affiliation: Department of Genetics and Molecular Biology, Medical School of Xi'an Jiaotong University / Key Laboratory of Environment and Disease-Related Gene, Ministry of Education, Xi'an, China.
authors.forename: Tu-Sheng
authors.initials: TS
authors.lastname: Song
authors.affiliation: Department of Genetics and Molecular Biology, Medical School of Xi'an Jiaotong University / Key Laboratory of Environment and Disease-Related Gene, Ministry of Education, Xi'an, China.
authors.forename: Chen
authors.initials: C
authors.lastname: Huang
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood; D001798:Blood Proteins / Q000378:metabolism; D001943:Breast Neoplasms / Q000097:blood* / Q000378:metabolism* / Q000473:pathology; D018270:Carcinoma, Ductal, Breast / Q000097:blood* / Q000378:metabolism* / Q000473:pathology; D016022:Case-Control Studies; D005591:Chemical Fractionation; D002846:Chromatography, Affinity; D002852:Chromatography, Ion Exchange; D005260:Female; D006801:Humans; D060328:Magnetic Phenomena; D008863:Microspheres; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009363:Neoplasm Proteins / Q000378:metabolism; D040901:Proteomics / Q000379:methods*; D011786:Quality Control; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*
chemical_list: D014408:Biomarkers, Tumor; D001798:Blood Proteins; D009363:Neoplasm Proteins
keywords: MALDI-TOF MS; MB-IMAC-Cu; MB-WCX; biomarker; intraductal carcinoma