alpha-catenin expression is decreased in human gastric cancers and in the gastric mucosa of first degree relatives.

BACKGROUND AND AIMS The role of altered cell adhesion is critical for the development of epithelial cancers. E-cadherin plays an important role in the maintenance of cell-cell adhesion and its function is thought to be regulated by its associated cytoplasmic proteins, such as α-catenin and β-catenin. To determine the role of α-catenin expression in gastric carcinogenesis, we studied its expression in human gastric cancer and in the gastric mucosa of first degree relatives with no clinical disease. METHODS α-Catenin expression was assessed by immunohistochemical analysis and reverse transcriptase-polymerase chain reaction (RT-PCR) using gastric tissue specimens from patients with gastric cancer and from the gastric mucosa of first degree relatives of gastric cancer patients and healthy controls. RESULTS mRNA levels of α-catenin were reduced or absent in 13 of 19 gastric cancer tissues, which differed significantly from levels found in the tumour free gastric mucosa of cancer patients (p Helicobacter pylori infection (p CONCLUSION Our findings suggest that loss or downregulation of α-catenin expression may be an early event in gastric carcinogenesis and may be associated with H pylori infection.