Abstract: Objective To investigate the effects of nimesulide on the expression of COX-2 and VEGF;and analyze the mechanism of nimesulide of inhibiting angiogenesis in pancreatic cancer.Methods PA NC-1 cells were treated with various concentrations of nimesulide(selective for COX-2 inhibitor).The expressions rates of COX-2 and VEG F were detected by immuno histo chemistry.The level of COX-2 mRNA and VEGF mR NA were measured by reverse transcriptase-polymerase chain reaction analysis(RT-PCR).Results The expressions rates of COX-2 and VEGF in 100,200,400μmo l/L group were significantly decreased mor e pancreatic cancer group than those in control group(P<0.05).The expressions between COX-2 and VEGF mentioned above showed fine correlation(r=01 785,P<0.05).RT-PCR revealed that the mR NA expression of COX-2 and VEGF were reduced with high concentration of nimesulide.Conclusion The inhibition of the expression of COX-2 and VEGF may play a certain role in the antitumor process of NSAIDs.