FIG. 5.

Transfection of the FLAP expression vector restored ROI production and ROI-dependent NF-κB activity in HCT-116 cells. (A) HCT-116 cells were transfected with the HIV-κB-CAT reporter plasmid alone or together with a FLAP expression vector, and CAT activities were measured in unstimulated cells or in cells stimulated with IL-1β for 6 h (50 U/ml), as indicated in the figure. The IL-1β treatment was performed in the absence or in the presence of either the FLAP inhibitor MK886 at 0.5 μM (column 5) and 1 μM (column 6) or the 5-LOX inhibitor ETYA at 35 μM (column 8) and 65 μM (column 9). Each column represents the mean of three independent experiments (± SD). Asterisks indicate that values were statistically different from the reference values (Δ). (B) Formation of ROIs in HCT-116 cells transiently transfected with the FLAP expression vector. Column 1, background (no DFCH probe); column 2, unstimulated, FLAP transfected cells; column 3, stimulation with IL-1β (50 U/ml); column 4, as in column 3 plus NAC (10 mM); column 5, as in column 3 plus NAC (20 mM); column 6, as in column 3 plus PDTC (60 μM); column 7, as in column 3 plus PDTC (100 μM); column 8, as in column 3 plus MK886 (0.5 μM); column 9, as in column 3 plus MK886 (1 μM); column 11, stimulation with IL-1β (50 U/ml); column 12, as in column 11 plus ETYA (35 μM); column 13, as in column 11 plus ETYA (65 μM); columns 10 and 14, stimulation with H₂O₂ (250 μM). Asterisks indicate that values are statistically different from the reference values (Δ).