Matrine inhibits the proliferation of HepG2 cells in nude mice. (A, B) Typical photographs of tumor samples from the nude mice treated with different doses of matrine. HepG2 cells were implanted by subcutaneous injection into the right fore leg of the nude mice. Different doses of matrine were administered to the mice by subcutaneous injection every other day. Mice in control group were given physiological saline alone. After 3 weeks, the mice were sacrificed. (C, D) Volume and Weight of tumor samples from nude mice treated with different doses of matrine. Data are reported as means ± S.D. of three separate experiments. *p < 0.05, **p < 0.01 vs. control. (E) Subcellular location of AIF in tumor samples from the control group and the 100 mg/kg matrine-treated group were analyzed by immunohistochemistry.