Identification of Annexin A1 protein expression in human gastric adenocarcinoma using proteomics and tissue microarray

Figure 1 Mass spectrum of the isotopic distribution patterns of Annexin A1 (GLGTDEDTLIEILASR) and ESI-Q-TOF-MS analysis results. A: Theoretical isotopic distribution patterns (M0, relative abundance of theoretical monoisotopic peaks, M2, relative abundance of theoretical 2 Da monoisotopic peaks; M4, relative abundance of theoretical 4Da-monoisotopic peaks); B: Isotopic distribution patterns after ¹⁸O labelling, I0, actual detected relative abundance of theoretical monoisotopic peaks,I2, actual detected relative abundance of theoretical 2Da-monoisotopic peaks; I4, actual detected relative abundance of theoretical 4Da-monoisotopic peaks; C: Amino acid sequence at m/z 854.00 was identified as GLGTDEDTLIEILASR; D: Protein sequence of Annexin A1 (ANXA1) showing the underlined MS/MS fragment matched the 128-143 amino acid residues of ANXA1.

Figure 2 Expression of Annexin A1 protein in gastric adenocarcinoma cells and normal gastric epithelial cells by western blot analysis. T: Gastric adenocarcinoma cells; N: Normal gastric epithelial cells.

Figure 3 Representative immunohistochemical staining patterns of Annexin A1 expression in gastric carcinoma and normal gastric mucosa. A: Strongly positive staining; B: Moderately positive staining; C: Weakly positive staining; D: Negative staining (immunohistochemical staining × 400).