Effect of the biflavonoids extract of S. doederleinii on (A) LLC and B16 cells growth; and (B) tumor growth in male C57BL/6 mice. Mice were inoculated with LLC for 2 weeks prior to per os (p.o.) 50 and 150 mg/kg of the extract dissolved in component solvent (consisting of double distilled water, ethanol, propylene glycol, and PEG-400) once a day for 12 days; (C) Tumor weights were recorded. Data are expressed as means ± SD, n = 10 mice per group. * p < 0.05; ** p < 0.01, significantly different as indicated; (D) Hematoxylin and eosin (H&E) staining (×100), and (E) CD31 staining (×400) of xenograft tumors in each group. Arrows indicate the tumor necrosis region.