NF-κΒ expression was measured in the cytoplasm, nuclei and whole cell lysate in order to determine whether NF-κΒ is translocated to the nucleus induced by TNF-α. Because IKK and IκB are both cytoplasmic proteins, and also interact with NF-κΒ in the cytoplasm, these proteins could only be detected in the cytoplasmic samples. In blot images, C represents control, K represents KLT only, T represents TNF-α only and T+K represents TNF-α plus KLT. Experiments were performed in triplicate. (A) NF-κΒ p65 expression in the cytoplasm. (B) NF-κΒ p65 expression in the nuclei. (C) NF-κΒ p65 expression in whole cells. (D) IκBα expression in the cytoplasm. (E) IKKα expression in the cytoplasm. (F–I) Bar diagrams of densitometric analysis of NF-κΒ, IKKα and IκΒα expression in the four CRC cell lines. NF-κΒ-c represents NF-κΒ expression in cytoplasm, NF-κΒ-n represents NF-κΒ expression in nuclei, and NF-κΒ-w represents NF-κΒ expression in the whole cell. *P < 0.05 indicates a significant difference compared to the control group. Full length blots of A–E are shown in Supplementary Figure 5.