title: Proteome of human colon cancer stem cells: a comparative analysis.
abstract: OBJECTIVE
  To isolate and identify the biological characteristics of human colon cancer stem cells (SW1116 cells) and further study their proteome.
  
  
  METHODS
  SW1116 cells were isolated and cultured with a serum-free medium (SFM). Sphere formation was assayed to observe the formation of colon cancer stem cell spheres. SW1116 cells were inoculated into a serum-containing medium for observing their differentiation characteristics. Proliferation curve and cross-resistance of SW1116 cells to different drugs were detected by MTT. Percentage of SP cells in SW1116 cells was detected with Hoechst33342 staining. Telomerase activity in SW1116cells was checked by polymerase chain reaction (PCR)-enzyme linked immunosorbent assay. Expressions of stem cell relevant genes and proteins were detected by reverse transcription-PCR and Western blot, respectively. Total protein was isolated from SW1116 cells by two-dimensional gel electrophoresis (2-DE) and differentially expressed proteins were identified by tandem mass spectrometry (MALDI-TOF/TOF).
  
  
  RESULTS
  The isolated SW1116 cells presented as spheroid and suspension growths in SFM with a strong self-renewal, proliferation, differentiation and drug-resistance ability. The percentage of SP cells in SW1116 cells was 38.9%. The SW1116 cells co-expressed the CD133 and CD29 proteins. The telomerase activity in SW1116 cells was increased. The expressions of different stem cell relevant genes and proteins were detected. The proteomic analysis showed that the 26 protein spots were differently expressed in SW1116 cells and 10 protein spots were identified as ubiquitin fusion-degradation 1-like protein, nuclear chloride channel protein, tubulin β, Raichu404X, stratifin, F-actin capping protein α-1 subunit, eukaryotic translation elongation factor 1 delta isoform 2, hypothetical protein, glyceraldehyde-3-phosphate dehydrogenase and guanine nucleotide binding protein β polypeptide 2-like 1, respectively.
  
  
  CONCLUSIONS
  SW1116 cells are biologically characterized by self-renewal, proliferation and differentiation, and the differently expressed proteins in SW1116 cells may be essential for isolating cancer stem cells.
authors: Department of Gastroenterology, Huadong Hospital, Fudan University, Shanghai 200040, China.
authors: Jian
authors: J
authors: Zou
authors: Xiao-Feng
authors: XF
authors: Yu
authors: Zhi-Jun
authors: ZJ
authors: Bao
authors: Jie
authors: J
authors: Dong
mesh_terms: D001562:Benzimidazoles / Q000494:pharmacology; D002454:Cell Differentiation; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D003110:Colonic Neoplasms / Q000378:metabolism*; D016895:Culture Media, Serum-Free / Q000378:metabolism; D019008:Drug Resistance, Neoplasm; D015180:Electrophoresis, Gel, Two-Dimensional; D020869:Gene Expression Profiling; D006801:Humans; D014411:Neoplastic Stem Cells / Q000378:metabolism*; D020543:Proteome; D040901:Proteomics / Q000379:methods*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D019098:Telomerase / Q000378:metabolism
chemical_list: D001562:Benzimidazoles; D016895:Culture Media, Serum-Free; D020543:Proteome; D019098:Telomerase; C017807:bisbenzimide ethoxide trihydrochloride