Fig. 2.

Normal and diseased 129:Stat1 ^−/− mammary glands with mammary intraepithelial neoplasia (MIN). This figure compares representative mammary whole mounts and representative hematoxylin and eosin (H&E)-stained histology for (a and b) an 88-week-old nulliparous 129:wild type (129:WT), (c and d) tumor-free 129:Stat1 ^−/−, and (e and f) 120-week-old nulliparous tumor-bearing 129:Stat1 ^−/− . The tumor-free knockout and WT are normal (a–d). The whole mount from the nulliparous, tumor-bearing, 120-week-old 129:Stat1 ^−/− female shows extensive lobuloalveolar development and two cystic MIN (arrows) (e). The H&E staining shows cystic lesions and a dense duct without a visible lumen filled with precancerous large oval pale cells (MIN) (f). Scale bars = 500 μm