Figure 2

Activation of WNT signalling in the antral glands leads to rapid adenoma formation. (a) IHC detecting β-catenin showing nuclear localisation in antrum tissue from AhCreER⁺ APC^fl/fl (APC), AhCreER⁺⁺ Catnb^{exon3fl/exon3fl} (Bcat) and AhCreER⁺ GSK3 alpha^fl/fl beta^fl/fl (GSK3) mice versus AhCreER⁺ (WT) only mice at day 4 post-induction. Scale bar, 10 μm. (b) H+E stain of an antral tumour from AhCreER⁺ GSK3 alpha^fl/fl beta^fl/fl (GSK3) mouse at day 136 post-induction (single inducer injection). Scale bar, 200 μm. (c) In-vivo RFP fluorescence imaging of AhCreER⁺ Rosa26^tdRFP APC^fl/fl (left) and AhCreER⁻ Rosa26^tdRFP APC^fl/fl (right) mice at day 10 post-induction. Arrows indicate thickened areas of glandular stomach. BF, bright field. (d) Haematoxylin and eosin (H+E) stain of an antral tumour from AhCreER⁺ GSK3 alpha^fl/fl beta^fl/fl (GSK3) mouse at day 8 post-induction with a high magnification panel (right). Scale bar, 20 μm. (e) Antral neoplasia in AhCreER⁺ GSK3 alpha^fl/fl beta^fl/fl mice at day 8 post-induction. IHC staining reveals high levels of nuclear β-catenin with corresponding c-MYC and Sox9 staining, as well as high levels of proliferation (BrdU and ki67-positive cells). Scale bar, 50 μm.