PTGS2 and neoplasm: It has been shown that the NFκB transcriptional activity in gastric mucosa is induced during aging [53], that positive NFκB expression as assessed through immunohistochemistry is observed in 73.5% of human CRC tumors independent of age [50], and that levels of NFκB, IKKα and COX2 in tumor epithelial cells from CRC patients are significantly higher than adjacent normal tissue [52].