(A) Apoptosis was measured in tumor tissues using the TUNEL assay and (C) phospho-p38 expression was measured in tumor tissues by immunohistochemistry. (B) TUNEL-positive and (D) p-p38-positive cells were observed under a light microscope and are shown as the average of four fields. Significance was determined by Student’s t test, *P<0.05, compared with the untreated control. (E) Histological toxicity analysis of the liver and kidney in nude mice by H&E staining. Slides were observed under a light microscope (scale bar, 10 μm).