Fig. 1.

(a) Chemical structure of ABAQ (ABAQ, C₁₆H₁₁N₃O₂, MW = 277.28). (b) A high-grade colonic dysplasia on H&E-stained section from a mouse in group 2 (200 ppm ABAQ + DSS). Note: Nuclear atypia in the crypts and Paneth's granules (red in color) in the cytoplasm of some dysplastic crypt cells. H&E stain; bar, 50 μm. (c) Many nuclei in the high-grade dysplasia in a serial section from (b) are positive for MCM2. MCM2 immunohistochemistry; bar, 50 μm. (d) Most nuclei in the high-grade dysplasia in a serial section from (b) are negative for PDCD4, whereas the nuclei in the surrounding normal crypts are positive for PDCD4. PDCD4 immunohistochemistry; bar, 50 μm. (e) The cytoplasmic expression of β-catenin is present in the high-grade dysplasia lesion developed in the colon of a mouse from group 2 (200 ppm ABAQ + DSS). Some nuclei are weakly positive for β-catenin. β-Catenin immunohistochemistry; bar, 50 μm. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of the article.)