Translocation of annexin I from cellular membrane to the nuclear membrane in human esophageal squamous cell carcinoma

Figure 1 The localization of annexin I in normal esophageal epithelium. The normal esophageal epithelia on the paraffin-embed-ded tissues were detected with anti-annexin I monoclonal antibody and imaged with TRITC-conjugated goat anti-mouse antibody, and then observed under a fluorescence microscope (a, d, e, f and g). PBS was used as a negative control (a 50 ×), the tissue section was viewed under a Nomarski interference-contrast microscopy (b 50 ×) and the additional H & E staining was also performed (c 200 ×). The localization of annexin I protein in normal esophageal epithelium was shown from d to g (d 200 ×; e 400 ×; f 400 × and g 400 ×). The orientation of the bottom left corner was the basal membrane of the esophageal mucosa.

Figure 2 The translocation of annexin I protein in ESCC. Paraffin-embedded tissue sections of ESCC were detected with anti-annexin I antibody and annexin I protein was labeled by TRITC-conjugated secondary antibody. The fluorescence image was visualized under a fluorescence microscope (Olympus BX51, Japan). An H & E staining was performed (a 200 ×; c 400 ×). A hyperplasia of esophageal epithelia were shown in Figure 2 (a and b, b 200 ×) and there were basal papillae displaying bound-ary area of the epithelium, which consecutively expressed annexin I formed the typical trammel net on the cellular membrane. Annexin I protein was decreased sharply and translocated from cellular membrane to the nuclear membrane (d 200 ×; e 400 ×; f 400 ×). The yellow arrows showed the nuclear membrane localization of annexin I in ESCC and all of the materials were from a same ESCC case.

Figure 3 The localization of annexin I in ESCC cell line. EC0156 cells were grown on glass coverslips at 80% confluence, de-tected with the anti-annexin I monoclonal antibody and visu-alized by FITC-conjugated secondary antibody under the fluo-rescence microscope. EC0156 cells were cultured in DMEM medium and photomicrographied under a phase-contrast mi-croscopy (a 100 ×). Annexin I was observed by fluorescence microscope (b 400 × and c 1000 ×). The red arrows showed that annexin I protein was also located on nuclear membranes in EC0156 cells.