RESUMEN
Claudins are a family of transmembrane proteins which are essential for the formation and maintenance of epithelial tight junctions. Altered expression of claudins may lead to structural and functional damage of tight junctions, which plays an important role in tumorigenesis and cancer progression. The expression of claudin-3 in gastric cancer is not yet well understood. AIM: To evaluate the expression of claudin-3 in gasric cancer and in adjacent normal mucosa and its association with clinical and pathological parameters. SUBJECT AND METHODS: Tissue specimens from a total of 69 patients with gastric cancer were obtained. Immunohistochemical reactions were performed using mouse polyclonal antibodies to claudin-3. RESULTS: The expression of claudin-3 in gastric cancer was significantly higher than in adjacent normal mucosa (p<0,05). The absence of claudin-3 was significantly associated with poor differentiation (p<0,05). An abnormal nuclear expression of claudin-3 was observed in 69.6% cases. A significant association was found between nuclear expression and the absence of membranous claudin-3 expression (p<0,05).