Research Article

Downregulation of S100 Calcium Binding Protein A9 in Esophageal Squamous Cell Carcinoma

Figure 3

Expression of S100 calcium binding protein A9 in Grade I ESCC. S100A9 expression was observed in the foci of keratinization (keratin pearls) in Grade I tumors with cytoplasmic and nuclear localization. The degree of S100A9 immunostaining varied with the level of keratinization in tumor cells. Stroma showed no S100A9 expression. All the images were acquired at 200x and 400x magnification. Scale bars = 50 μm and 20 μm.