Decreased Expression of Caveolin-1 and E-Cadherin Correlates with the Clinicopathologic Features of Gastric Cancer and the EMT Process

Background: Recent researches and relevant patents have been reported to prove the significant value of Caveolin-1 (Cav-1) in cancer diagnosis and treatment. Objective: Our study aimed to study the role of Cav-1 in gastric cancer progression and investigate the relationship between Cav-1/E-cadherin expression and the clinical status of gastric cancer. Method: Immunohistochemistry was applied to detect the expression of Cav-1 and E-cadherin in gastric cancer in a tissue microarray. Real-time PCR was used to further detect the mRNA expression of Cav-1 and E-cadherin in tumor-derived and peritumoral tissues and in different gastric cancer cell lines. The expression of E-cadherin was analyzed by Western Blot and the cell migration ability was examined by Transwell migration assays after downregulation of Cav-1 using siRNA. Results: The staining of Cav-1 and E-cadherin were both strong in all 5 of the normal gastric tissues, while in gastric cancer tissues the staining of Cav-1 and E-cadherin were downregulated (44&33 negative, 21&22weak and 5&15 strong). And their level was correlated with tumor clinical stage, pathological grade, and metastasis status. Moreover, there was a positive correlation between Cav-1 expression and E-cadherin expression in gastric cancer tissues(r = 0.42, P < 0.05). Knockdown of Cav-1 resulted in decreased expression of E-cadherin, cell morphology changes and elevated migration ability of gastric cancer cells. Conclusion: Decreased expression of Cav-1 and E-cadherin may play an important role in the progression of gastric cancer; Knockdown of Cav-1 may promote EMT of gastric cancer by targeting E-cadherin.