Radiation enhancement of celecoxib on gastrical SGC7901 cell line

OBJECTIVE: To investigate the radiosensitivity enhancement effect of cyclooxygenase-2(COX-2) inhibitor celecoxib on gastric cancer cells in vitro and to initially disclosure its mechanism.METHODS:MTT assay was used to measure the proliferation inhibition of celecoxib on SGC7901 cells and determine the concentration IC50.The clonogenic assay was performed to determine the radiosensitizing effect of celecoxib on gastric cancer cells with the concentration of 20% IC50.The cell cycle distribution was analyzed by flow cytometry(FCM).RESULTS: Inhibition of cell proliferation seemed more dependent on the dose and the time.The IC50 of 48 h was 34.38 μmol/L.The group of radiation combined with celecoxib displayed the value of SF2,D0,Dq,SER was significantly lower than those of radiation alone group.Cell cycle analysis showed that the cell population in G2/M phase increased and in S phase decreased.CONCLUSIONS: COX-2 inhibitor celecoxib can obviously enhance the radiosensitivity of SGC7901 cells,which is probably associated with the inhibition of sublethal damage of tumor cells and facilitation of redistribution of tumor cell cycle.