PCNA and cholesteatoma: As shown in Figure 2, positive p-EGFR immunostaining was mainly observed in the cell cytoplasm and membrane of cholesteatoma epithelium in the basal and suprabasal layers (Figure 2(a)); p-Akt positive reactions were mainly localized in the cytoplasm of epithelium in the basal and suprabasal layers (Figure 2(c)); cyclinD1 expression was mainly observed in the nuclei and was localized in the basal layer of the epithelium (Figure 2(e)); PCNA positive reactions were mainly observed in the nuclei and was localized in the basal and suprabasal layers (Figure 2(g)).