The suppressive effects of nimesulide, troglitazone and bezafibrate on the development of colonic adenocarcinoma was well correlated with the inhibition of cell proliferation activity, induction of apoptosis, and lowered immunoreactivity of β-catenin, COX-2, iNOS, and nitrotyrosine in the colonic malignancies. Here, PTGS2 is linked to colon adenocarcinoma.