Figure 5: Identification of proteins regulated by NPM1: In order to identify proteins regulated by the NPM1 expression, we performed siRNA knockdown and GeLC-MS analyses in four Ewing’s sarcoma cell lines (A673, TC71, SKES1 and CHP100). The four Ewing’s sarcoma cell lines were treated with either NPM1 siRNA (SASI_ Hs01_00214118; SIGMA-ALDRICH) or negative control siRNA (SIGMA-ALDRICH). A Western blot analysis confirmed that the cells treated with NPM1 siRNA exhibited a significant decrease in the NPM1 expression compared to the controls. These protein samples were then analyzed using GeLC-MS to obtain their protein profiles, and the acquired data were calculated as semiquantitative expressions (control vs siRNA). Approximately 1,500 proteins were identified in each cell line (Table 2). Finally, 36 upregulated proteins and 18 downregulated proteins were identified as common proteins in the four cell lines (Table 3).