In vivo and in vitro antitumor activities of C. crepidioides on S-180 cells. (A) Inhibition of growth of S-180 cells in nude mice. Growth of the tumors after subcutaneous inoculation of S-180 cells. Note the growth-suppressive effect of C. crepidioides. Data are mean ± SD of four mice in each group. The P values are the results of statistical analysis of the C. crepidioides and control data. (B) H&E-stained tissues demonstrating the pathological changes induced by treatment with C. crepidioides. Magnification, ×1000. (C) C. crepidioides does not have any antitumor activity on S-180 cells by itself. S-180 cells were cultured with the indicated concentrations of C. crepidioides extract for 24, 48 or 72 h, and cell growth was determined in triplicate cultures by WST-8 assay. (D) Cytotoxic effect of C. crepidioides on RAW264.7 cells. The cell growth was determined in triplicate cultures by WST-8 assay. Cell growth in untreated control cultures was considered 100%. Data are mean ± SD of triplicate cultures expressed as percentage of the control.