When subcutaneous H292 tumor xenografts reached 100–200 mm3, mice received PBS (1% DMSO and 5% Tween80), 40 mg/kg physalin A, 80 mg/kg physalin A, or 5 mg/kg cisplatin via intraperitoneal injection for 10 days. (A) Tumor volumes were measured at the indicated times using Vernier calipers. (B) The average tumor weight and (C) body weight of each group was measured on the last day of the experiment (day 10). (D) The anti-tumor rate was also determined at the end of the experiment. (E) Protein levels of pSTAT3 (Tyr705), total STAT3 and cleaved-caspase 3 in tumor tissues of mice in each treatment group. β-actin was used for normalization. *, †, ‡p < 0.05, significantly different from the *control, †PA (40 mg/kg), and ‡PA (80 mg/kg) groups.