As regulation of mPGES-1 and COX-2 are impaired in various types of cancer, high levels of mPGES-1 and \documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\hbox {PGE}_{2}$$\end{document} are present and are linked to the chronic inflammation that contributes to a tumor-promoting microenvironment rendering COX, and especially COX-2 a strategic target for anti-cancer therapy16–21. This evidence concerns the gene PTGES and cancer.