IFN-γ reinforces the inhibitory effect of tumor necrosis factor-related apoptosis-inducing ligand on apoptosis of human colon cancer cell line RKO cells

AIM: To explore the influence of IFN-γ on the role of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) in inducing apoptosis of RKO cell line. METHODS: Survival fraction and apoptosis were measured by MTT method and flow cytometry (FACS). RESULTS: Survival fraction of IFN-γ group, TRAIL and IFN-γ 72 h+TRAIL group were 99.28%, 85.45%, 52.60%, respectively. The percentage of apoptotic cells of IFN-γ group, TRAIL group, IFN-γ 24 h+TRAIL group, IFN-γ 48 h+TRAIL and IFN-γ 72 h+TRAIL group were 1.51%, 2.38%, 4.97%, 13.30%, 21.00%, respectively. The percentage of apoptotic cells of IFN-γ 24 h+TRAIL group was higher than the sum of IFN-γ group and TRAIL group (P0.01). The longer the IFN-γ pretreated, the higher the percentage of apoptotic cells was observed (P0.01). CONCLUSION: IFN-γ can reinforce the effect of TRAIL inducing apoptosis in RKO.