Effect of EESP on phosphorylation of STAT3 in CRC mice. At the end of the experiment, tumor tissues from control and EESP-treated group were processed for immunohistochemical staining for phosphorylated STAT3 (pSTAT3) or total STAT3. The photographs are representative images taken at a magnification of 400 ×. Quantification of immunohistochemical assay was represented as percentage of positively-stained cells. Data shown are averages with S.D. (error bars) from 9 individual mouse in each group. *P< 0.01, versus controls.