Fig. 1.

SnoN localization varies in nontumorigenic versus malignant tissues and cell lines. Tissue sections derived from normal human mammary tissue (a–c), normal skin tissue (d), and stage II invasive ductal carcinoma (e) were stained for SnoN by using an antibody against the C (a, c–i) or N(b) terminus of SnoN. (c) The SnoN antibody was preincubated with a blocking peptide, as described in Methods. Endogenous SnoN was visualized in the nontumorigenic HMT-3522-S1 cell line (f), the invasive mammary carcinoma MDA-MB-231 cell line (g), primary HEKa (h), and the malignant melanoma A375 cell line (i). In all images, the nuclei were visualized by staining with Hoechst fluorescent dye.