Localization of C/EBPα, p63, AR and PSA in normal and cancerous prostate epithelium. Tissue sections of human prostate glands were stained with antibodies to C/EBPα, p63, AR and PSA as detailed in the Methods. Shown are representative fields of normal and hyperplastic epithelium (panels A-E) and regions with cancer (panels F-J). Panels A, E, F, and G were stained for C/EBPα, Panels D and H were stained for PSA, Panel B was stained for p63, and Panel C, I, and J were stained for AR. Panels A-D are shown at low magnification (10x objective) and Panels E-J at high magnification (40x objective). The thin arrows indicate representative areas staining positively for C/EBPα in normal and cancerous regions. In the normal or hyperplastic epithelium C/EBPα is detected in the basal layer. In Panel D strong staining of PSA is seen at the abluminal surface of the normal prostate epithelium while in Panel H weakly stained PSA is localized diffusedly throughout the cancerous epithelium. In panel I the thick arrow indicates cells staining positively for AR. In Panel J weak staining of AR is seen in some nuclei.