RÉSUMÉ
Objective To investigate the effect of nimesulide (NIM), a selective cyclooxygenase-2 (COX-2) inhibitor, on angiopoietins (Ang) gene expression of human glioma xenografts in nude mice and its significance. Methods Human SHG44 glioma cells were inoculated subcutaneously in 16 nude mice to establish xenograft models, and then these mouse models were randomly divided into NIM treatment group and control group. NIM (6 mg/kg) and saline were poured into the stomachs of the mice in each group, respectively, once daily for 35 d. The mRNA expressions of Ang-1 gene and Ang-2 gene in the xenografts were determined by RT-PCR. Microvessel density (MVD) in the xenografts was assessed by immunohistochemical technique. The tumor growth curve was drawn and the inhibition ratio of tumor growth was calculated. Results NIM could significantly inhibit the glioma xenografts growth with its inhibition rate reaching 42.03%. The mRNA expression of Ang-2 gene in NIM treatment group (0.2032±0.0185) was significantly lower than that in control group (0.6024±0.0289, P＜0.05), but that of Ang-1 gene showed no significant changes; therefore, the mRNA ratio of Ang-2/Ang-1 genes was decreased (0.5825±0.0621 vs. 1.5847±0.1948, P＜0.05). MVD in the xenografts of the NIM treatment group was significantly lower than that in the control group (P＜0.05). Conclusion NIM, by down-regulating the mRNA expression ofA ng-2 gene and changing the mRNA ratio of Ang-2/Ang-1 genes, can inhibit the tumor growth