In addition, western blot and immunofluorescence showed that the protein levels of epithelial marker (E‐cadherin) and mesenchymal marker (N‐cadherin) were regulated by the up‐ or down‐regulated CASC15, demonstrating that CASC15 could affect migratory and invasive abilities of GC cells by influencing epithelial‐to‐mesenchymal transition (EMT) progression. The gene discussed is CASC15; the disease is gastric cancer.