Background and objective: Aquaporin-4 (AQP4) is a member of the water channel protein family, which is thought to be associated with tumor development. A recent work suggests that AQP play key roles in tumor biology.
Methods: In this study, we measured the expression and localization of AQP4 in 60 gastric epithelial tumor cases and 10 normal tissue cases by immunohistochemistry, Western blotting and RT-PCR analysis.
Results: AQP4 protein and mRNA expression level in gastric cancer tissue were significantly lower than those in normal gastric tissue. No significant variations were found according to TNM stage, histological type, grade and distant metastasis.
Conclusion: Our results suggest that the expression of AQP4 is a marker of normal proliferating gastric epithelial cells. More cases and further research may be necessary to elucidate their exact role in normal or pathologic proliferation and/or differentiation.