Figure 3.

Effect of wogonin on the growth of HCT116 cells cocultured with LPS-induced THP-1 cells, the expression of inflammatory cytokines and NF-κB in human THP-1 monocytes. (a) MTT assay was performed to detect the anti-proliferation effect of wogonin. HCT-116 cells were seeded at a density of 4 × 10⁴ cells/well and cultured with or without the supernatant of THP-1 cells at ratios of 1 : 5, 1 : 10 and 1 : 20. LPS (10 μg/ml) and wogonin (50 μM) were used in this culture system. *P<0.05, **P<0.01 and n=5. (b) PCNA expression was analyzed by western blots. (c) Ki67 immunohistochemistry of HCT116 cells in conditional culture system. The production of IL-6 (d) and IL-1β (e) was measured in the culture medium using ELISA kits. (f) The mRNA levels of IL-6 and IL-1β were measured by real-time RT-PCR. All data are expressed as the mean±S.D., *P<0.05, **P<0.01 compared with control group; ^#P<0.05, ^##P<0.01 versus LPS group. After the isolation of nuclear and cytoplasm extracts, NF-κB p65 nuclear expression (g), IκB phosphorylation (h) and IKK phosphorylation (i) were measured by western blotting. (j) The production of IL-6 and IL-1β in THP-1 cells transfected with NF-κB p65 plasmid was measured in the culture medium using ELISA kits. **P<0.01 compared with LPS alone; ^#P<0.05, ^##P<0.01 versus LPS+wogonin group