PTGS2 and colorectal cancer: Using immunohistochemistry, we measured COX-2, NF-κB-p65, NF-κB-p65 nuclear localisation sequence (NLS), NF-κB-p50, NF-κB-p50 NLS and IKKα protein expression in matched colorectal biopsy samples comprising both non-tumour and adjacent tumour tissue from 32 patients with colorectal cancer.