title: [Proteomic research of biomarker of colorectal cancer metastasis].
abstract: OBJECTIVE
  To explore the potential markers of colorectal cancer metastasis and the influence of 5-FU on differentially expressed proteins by using proteomic technology, and to elucidate the mechanism of colorectal cancer metastasis.
  
  
  METHODS
  Human colorectal carcinoma cell lines of different metastatic potential, Lovo and SW480 were conventionally cultured, and the protein was extracted. 50% inhibitory concentration (IC(50)) of 5-FU to these two cell lines was measured by MTT assay. Proteins of these two cell lines after intervention by 5-FU at IC(50) were extracted, then 2-dimensional gel electrophoresis was conducted for the proteins. The differential protein spots were examined by mass spectrometry and analyzed by bioinformatics. Difference of expressed proteins in two cell lines before and after the intervention of 5-FU was validated by Western blot and immunofluorescence.
  
  
  RESULTS
  Eleven differentially expressed proteins were identified by 2-dimensional gel electrophoresis and mass spectrometry. The hnRNP K protein and PDI were selected to be examined by Western blot and immunofluorescence. Results revealed that the expression of hnRNP K in Lovo was higher than that in SW480, while the expression of PDI was lower in Lovo. After intervention by 5-FU at IC(50), the expression of hnRNP K in Lovo decreased more as compared to SW480, while the expression of PDI in SW480 increased more as compared to Lovo.
  
  
  CONCLUSIONS
  There are significant differences in expression of hnRNP K and PDI proteins between Lovo and SW480 cell lines, and the proteins alter regularly after 5-FU intervention.
authors.affiliation: Department of Surgery, The Sixth People's Hospital, Shanghai Jiaotong University, Shanghai 200233, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Zhang
authors.forename: Long
authors.initials: L
authors.lastname: Huang
authors.forename: Yan-lei
authors.initials: YL
authors.lastname: Ma
authors.forename: Jia-yuan
authors.initials: JY
authors.lastname: Peng
authors.forename: Tong-yi
authors.initials: TY
authors.lastname: Shen
authors.forename: Hong-qi
authors.initials: HQ
authors.lastname: Chen
authors.forename: Yu-kun
authors.initials: YK
authors.lastname: Zhou
authors.forename: Zhao-xin
authors.initials: ZX
authors.lastname: Chu
authors.forename: Ming
authors.initials: M
authors.lastname: Zhang
authors.forename: Huan-long
authors.initials: HL
authors.lastname: Qin
mesh_terms: D014408:Biomarkers, Tumor / Q000097:blood; D045744:Cell Line, Tumor; D015179:Colorectal Neoplasms / Q000378:metabolism* / Q000473:pathology*; D005472:Fluorouracil / Q000494:pharmacology; D006801:Humans; D009362:Neoplasm Metastasis; D040901:Proteomics
chemical_list: D014408:Biomarkers, Tumor; D005472:Fluorouracil