Hierarchical clustering analysis of candidate proteins was illustrated in heat map, which showed obvious differences between CP-induced cells and controls (Fig. 6). Each column is a sample and each rowindicates a differentially expressed protein. Log values (log2expression) of significantly differentially expressed proteins in different samples are displayed in heat maps in different colors. GreenandRedrepresent up-regulation and down-regulation, respectively. The gray part represents no quantitative information of the proteins. T1, T2 and T3 means the CP-treated U251 cells group and C2, C2 and C3 means control group (n=3).