Effect of inhibiting cyclooxygenase-2 expression on glioma immune microenvironment and biological behavior

Abstract

Objective To investigate the effect of celecoxib, a selective inhibitor of cyclooxygenase-2(COX-2), on glioma immune microenvironment and biological action in rat. Methods After treated with celecoxib, tumor volume and survive time were observed in a rat glioma model. COX-2, transforming growth factor-beta(TGF-β) and vascular endothelial growth factor(VEGF) expression in tumor tissue were detected using immunehistory and CD4+ CD25+ T cells was detected by flowcytometry. By using enzyme-linked immunosorbent assay (ELISA), the production of prostaglandin(PGE2), interlukin 10(IL-10) and interlukin 12(IL-12) were detected in rat serum. Results Tumor volume decreased after treated with celecoxib ((103.67±5.54)mm3, (151.60±8.34)mm3, P<0.01) and survive time of animals were prolonged ((42.87±1.72)d, (26.13±1.53)d, P<0.01). Expression of COX-2, TGF-β and VEGF in tumor tissue was down regulated after treated with celecoxib and number of CD4+ CD25+ T cells were decreased (5.32%, 7.84%, P<0.05). PGE2, IL-10 production in serum was obviously decreased by treatment of celecoxib ((223.66±33.79)pg/ml, (344.15±41.09)pg/ml, (98.69±10.99)pg/ml, (133.37±13.15)pg/ml, P<0.01) while the production of IL-12 was increased ((237.20±37.31)pg/ml, (117.90±19.20)pg/ml, P<0.01). Conclusion Celecoxib may improve the status of immunosuppression of rat glioma by several pass ways and modify tumor biological action. Celecoxib may give a good microenvironment for immunotherapy of gliomas. Key words: Gliomas; Cyclooxygenase 2; Tumor microenvironment; Immune escape