Protein Kinase B Phosphorylation Correlates with Vascular Endothelial Growth Factor A and Microvessel Density in Gastric Adenocarcinoma

Abstract

Objective: The signalling molecule protein kinase B (Akt) modulates many cellular processes. Phosphatidylinositol 3-kinase (PI3K)/Akt signalling pathways play important roles in tumour angiogenesis. The aim of this study was to determine the role of phosphorylated Akt (pAkt) in angiogenesis and its correlation with vascular endothelial growth factor (VEGF)-A in gastric adenocarcinoma. Methods: Tumour tissue and matched healthy gastric mucosa were obtained from patients undergoing surgical resection of gastric adenocarcinoma. Akt and pAkt were detected via Western blotting. VEGF-A, pAkt and CD34 were examined by immunohistochemistry. Results: Akt and pAkt protein levels were significantly higher in gastric cancer tissue than in normal tissue (n = 48 patients). Positive VEGF-A immuno -staining was significantly associated with pAkt immunostaining. Microvessel density was correlated with both VEGF-A and pAkt positivity. Conclusions: Phosphorylated Akt and VEGF-A are involved in angiogenesis of gastric adenocarcinoma, and Akt activation may contribute to angiogenesis via VEGF-A upregulation. The PI3K/Akt/VEGF signalling pathway may be involved in gastric adenocarcinoma.