Silencing of cyclooxygenase-2 inhibits the growth, invasion and migration of ovarian cancer cells

The present study aimed to investigate the effect of downregulating cyclooxygenase-2 (COX-2) expression on the growth of human ovarian cancer cells. The COX-2-specific small interfering RNA (siRNA) plasmid vector was constructed and then transfected into ovarian cancer cells. The expression of COX-2 mRNA and protein was detected by quantitative polymerase chain reaction and western blot analysis, respectively. Cell proliferation, apoptosis, cell cycle distribution and cell migration were assessed following knockdown of COX-2 by RNA interference (RNAi). Western blot analysis was used to identify differentially expressed angiogenesis- and cell cycle-associated proteins in cells with silenced COX-2. The expression levels of COX-2 in ovarian cancer cells transfected with siRNA were decreased, leading to a significant inhibition of ovarian cancer cell proliferation, migration and invasion. Western blot analysis revealed that silencing of COX-2 may inhibit vascular endothelial growth factor, matrix metalloproteinase (MMP)-2 and MMP-9 protein expression. In conclusion, the present study demonstrated that RNAi can effectively silence COX-2 gene expression and inhibit the growth of ovarian cancer cells, which indicates that there is a potential of targeting COX-2 as a novel gene therapy approach for the treatment of ovarian cancer.