Objective To investigate the effect of periplocin of cortex periplocae (CPP) on Stat3 signaling and its probable molecular mechanism of inducing apoptosis and anti-tumor activity. Methods Cell proliferation was detected by MTT. Cell apoptosis and cell cycle were investigated by flow cytometry. Expression of Stat3 protein in SMMC-7721 cells was analyzed by Western blot. Mcl-1, Survivin and XIAP mRNA expressions were measured by RT-PCR. Results CPP inhibited the proliferation of SMMC-7721 cells significantly,...