Interaction between cyclooxygenase-2, Snail, and E-cadherin in gastric cancer cells

Figure 3 Down-regulation of nuclear factor-κB by p65-siRNA reversed the regulatory effect of celecoxib and prostaglandin E2 on Snail and E-cadherin in SGC-7901 cells. Treatment of SGC-7901 cells with celecoxib led to a reduced expression of Snail but an increased expression of E-cadherin both at mRNA (A) and protein (B) levels. In contrast, treatment of SGC-7901 cells with prostaglandin E2 (PGE2) led to an increased Snail and a decreased E-cadherin at mRNA (A) and protein (B) levels. However, when the cells were pre-treated with p65-siRNA, the observed effects of Celecoxib and PGE2 were reversed (A, B). mRNA expression was examined by polymerase chain reaction (qPCR) and expressed as a relative arbitrary unit against that of β-actin. Protein expression was examined by Western blot (^aP < 0.05 vs their respective controls).