ABSTRACT
Objective To observe the effect of combined treatment with rhTRAIL(recombinant human TNF-related apoptosis inducing ligand) and selective Cox-2 inhibitor Celecoxib on gallbladder carcinoma in vitro and to explore the possible mechanism of the effect. Methods Western blot analysis was used to detect the expression of c-FLIP and death receptors after treatment by Celecoxib. Apoptosis of gallbladder cell line SGC-996 after the combined treatment with Celecoxib and rhTRAIL was detected in three ways: (1) phase microscopy of the cells, (2) detection of effector caspase-3 and caspase-7 activity, and (3) determination of the proportion of apoptotic cells labeled by Annexin V-PI flow cytometric analysis using CELLQUEST software. Results Celecoxib down-regulated the expression of c-FLIPs and up-regulated the expression of DR5 in a dose- and time-dependent mode on cell line SGC-996. Apoptotic levels in the combined treatment group in cell line SGC-996 were significantly higher than those in the single drug treatment group and control group. Conclusion Celecoxib markedly sensitized rhTRAIL-induced apoptosis through the down-regulation of c-FLIPs and up-regulation of DR5 in gallbladder carcinoma cell line SGC-996.