title: Comparative proteomic analysis of differentially expressed proteins between K562 and K562/ADM cells.
abstract: BACKGROUND
  Multidrug resistance to chemotherapeutic agents is an important clinical problem during the treatment of leukemia. The resistance process is multifactorial. To realize the total factors involved in multidrug resistance, we analyzed the differentially expressed proteins of K562 and K562/ADM cells and we investigated one of the up-regulated proteins (CRKL) using siRNA to determine its role in K562/ADM cells.
  
  
  METHODS
  Altered protein expressions between K562/S (K562 ADM-sensitive cell line) and K562/ADM (K562 multidrug resistant cell line induced by adriamycin) were identified by 2D-DIGE coupled with mass spectrometry. Meanwhile, we confirmed the differential expression of CRKL and Stathmin in both K562 and K562/ADM cells by Western blot analysis. Furthermore, we used RNA interference to silence the CRKL gene expression.
  
  
  RESULTS
  Among the 9 differentially expressed proteins, 3 were up-regulated in K562/ADM cells, while 6 were down-regulated in the K562/ADM cells compared with its parent cell line. The expression of CRKL was up-regulated significantly in K562/ADM cells, and it can be decreased by recombinant lentivirus. Moreover, the multidrug resistance of K562/ADM cells was efficiently reversed by silence of CRKL gene expression.
  
  
  CONCLUSIONS
  The data provided the differentially expressed proteins in K562 and its resistant cell line and highlights the power of 2D-DIGE for the discovery of resistance markers in cancer. We found CRKL may be a new protein involved in the multidrug resistance of leukaemia cells.
authors: Shanghai Xinhua Hospital, Shanghai Children's Medical Center Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai 200127, China.
authors: Shao-hua
authors: SH
authors: Shen
authors: Long-jun
authors: LJ
authors: Gu
authors: Pei-qing
authors: PQ
authors: Liu
authors: Xin
authors: X
authors: Ye
authors: Wei-shan
authors: WS
authors: Chang
authors: Ben-shang
authors: BS
authors: Li
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000032:analysis / Q000037:antagonists & inhibitors / Q000235:genetics; D000595:Amino Acid Sequence; D004317:Doxorubicin / Q000494:pharmacology*; D018432:Drug Resistance, Multiple; D006801:Humans; D020014:K562 Cells / Q000737:chemistry* / Q000187:drug effects; D008969:Molecular Sequence Data; D009363:Neoplasm Proteins / Q000032:analysis*; D009687:Nuclear Proteins / Q000032:analysis / Q000037:antagonists & inhibitors / Q000235:genetics; D040901:Proteomics; D050777:Stathmin / Q000032:analysis
chemical_list: D048868:Adaptor Proteins, Signal Transducing; C082869:CRKL protein; D009363:Neoplasm Proteins; D009687:Nuclear Proteins; C493995:STMN1 protein, human; D050777:Stathmin; D004317:Doxorubicin