Figure 5. H&E-stained liver tumors from mice treated with WT ARF_26–44 peptide.

Hepatic tumors were induced in Foxm1^fl/fl mice with DEN/PB treatment, and then they were treated with daily i.p. injections of 5 mg/kg body weight of WT ARF_26–44 peptide or mutant ARF_37–44 peptide for 4 or 8 weeks (see Figure 2A legend). Arrows indicate red-staining cells undergoing apoptosis, and arrowheads show liver tumor margins. (A–F) H&E-stained liver tumor sections from WT ARF_26–44 peptide–treated mice revealed that many of the hepatic adenomas and HCC tumor cells stained red and were rounded up, which is indicative of apoptosis. E and F are higher-magnification images of C and D. No red-staining apoptotic cells were found in either the surrounding, normal liver tissue or in liver tumors from dsRNA CKO Mx-Cre Foxm1^–/– mice (see Figure 1, E–G). (G–L) No red-staining tumor cells were found in H&E-stained liver tumor sections from mice treated with either PBS or mutant ARF_37–44 peptide. Magnification, ×200 (A–D and G–L); ×400 (E and F).